A link assessment method and apparatus

Abstract

The application relates to a link measurement method and device, which can be applied to Internet of Vehicles, such as V2X, LTE-V, V2V, etc., or can be used in the fields of intelligent driving, intelligent networked vehicles, etc. A first terminal device receives at least one reference signal in a first reference period, and the at least one reference signal is non-periodically transmitted. The first terminal device determines a first target reference signal in the first reference period according to the at least one reference signal. The first terminal device obtains synchronization indication information or out-of-step indication information of a first link according to at least one target reference signal in at least one reference period, the first link is a link between the first terminal device and a second terminal device, the at least one reference period includes the first reference period, and the at least one target reference signal includes the first target reference signal. The number of non-periodic reference signals is uncertain, and the first terminal device can complete link evaluation according to the non-periodically transmitted reference signals.

Description

[0001] This application is a divisional application, the original application number is 201910691410.8, the original application date is July 29, 2019, and the entire contents of the original application are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the field of communication technology, in particular to a link evaluation method and device. BACKGROUND

[0003] Because wireless channels are used as transmission media in wireless networks, they are inherently unstable, so they are more unreliable than traditional wired network transmission and are more susceptible to physical environment and co-frequency wireless networks. The wireless channel used as the transmission carrier in the wireless local area network has the characteristic of time-varying. Time-varying refers to the quality of the transmission medium, which can vary greatly with time. Specifically, the packet loss rate, frame error rate and retransmission times in the wireless local area network can vary greatly according to different time periods, thereby greatly affecting the quality of service. In addition to the influence of complex environmental factors such as signal fading, environmental noise, channel interference and personnel movement around, the quality of the wireless link is unstable, so it is particularly important to measure and track the quality of the wireless link in the actual environment.

[0004] Radio link monitoring (RLM) refers to the continuous tracking of the quality of the wireless link by the terminal device in the connected state. For a link between the terminal device and the base station, the base station configures a reference signal (RS) for the terminal device, which can be referred to as RLM-RS, and the terminal device performs synchronization evaluation or out-of-sync evaluation on the link according to the received reference signal. The current reference signal is periodic, and the terminal device can receive the reference signal once every period. When performing evaluation, the terminal device can evaluate according to the reference signals received in one or more periods.

[0005] In the next generation communication system, sidelink (SL) communication scenarios supporting vehicle to everything (V2X) are supported. Communication between vehicles and anything, V2X includes vehicle to vehicle (V2V) communication, vehicle to pedestrian (V2P) communication or vehicle to infrastructure / network (V2I / N) communication. There is also a demand for RLM on the sidelink, which may use aperiodic reference signals for wireless link measurement, but there is currently no method for wireless link measurement based on aperiodic reference. SUMMARY

[0006] Embodiments of the present application provide a link measurement method and device, which provide a way of measuring a link according to an aperiodic reference signal.

[0007] In a first aspect, a link measurement method is provided, which includes: a first terminal device receiving at least one reference signal from a second terminal device within a first reference period, the at least one reference signal being aperiodically transmitted; the first terminal device determining a first target reference signal in the first reference period according to the at least one reference signal; and the first terminal device obtaining synchronization indication information or out-of-sync indication information of a first link according to at least one target reference signal in at least one reference period, the first link being a link between the first terminal device and the second terminal device, the at least one reference period including the first reference period, and the at least one target reference signal including the first target reference signal.

[0008] The method can be performed by a first communication device, which can be a communication device or a communication device capable of supporting the functions required by the communication device to implement the method, such as a chip system. Illustratively, the first communication device is a first terminal device. Illustratively, the first terminal device is a first terminal device, or a chip system provided in the first terminal device for implementing the functions of the terminal device, or other components for implementing the functions of the first terminal device.

[0009] In the embodiments of the present application, the first terminal device receives at least one reference signal in a first reference period, and the first terminal device obtains a first target reference signal according to the at least one reference signal, and the first terminal device can obtain the first target reference signal for each reference period if there is at least one reference period, so that the first terminal device can perform synchronization measurement on the first link according to the at least one first target reference signal to obtain synchronization indication information, or perform out-of-sync measurement to obtain out-of-sync indication information. That is, no matter how many reference signals the first terminal device receives in a reference period, the first terminal device can obtain a first target reference signal according to at least one reference signal for evaluation. In this way, the problem of uncertain number of aperiodic reference signals is solved, so that the first terminal device can complete the measurement on the link according to the aperiodic reference signals.

[0010] The evaluation, measurement and monitoring of the link quality described in the embodiments of the present application are equivalent, that is, the concepts of "evaluation", "measurement" and "monitoring" in the embodiments of the present application can be replaced with each other.

[0011] In a possible implementation, the method further includes: determining, by the first terminal device, whether the first link fails according to the synchronization indication information or the out-of-sync indication information.

[0012] After obtaining the synchronization indication information or the out-of-sync indication information, the first terminal device can determine whether the first link fails, and if the first link fails, the first terminal device can perform subsequent corresponding processing.

[0013] In a possible implementation, the first terminal device determines the first target reference signal in the first reference period according to the at least one reference signal, including: the first terminal device determines one of the at least one reference signal as the first target reference signal; or, the first terminal device combines part or all of the at least one reference signal to obtain the first target reference signal.

[0014] The first terminal device can select one reference signal as the first target reference signal at will, or can combine part or all of the at least one reference signal to obtain the first target reference signal. No matter which way is used, the problem of using aperiodic reference signals for measurement is solved. One way of combination is, for example, linear averaging of multiple reference signals, or there can be other ways of combination, such as assigning a corresponding weight to each reference signal in multiple signals, weighted averaging of multiple reference signals, etc. The specific combination method is not limited. By combining the received aperiodic reference signals, the measurement result is more accurate and can better reflect the average state of the channel quality in a period of time.

[0015] In a possible implementation, the first terminal device determines the first target reference signal in the first reference period according to the at least one reference signal, including:

[0016] In a case where the cumulative density of the first N reference signals in the at least one reference signal is greater than or equal to a reference density, the first terminal device takes the first N reference signals as the first target reference signal, N being greater than or equal to 1, wherein the density of a reference signal is the number of frequency domain units carrying the reference signal in the bandwidth occupied by the reference signal, and the cumulative density of the reference signal is the sum of the densities of one or more reference signals; or,

[0017] In a case where the cumulative bandwidth of the first N reference signals in the at least one reference signal is greater than or equal to a reference bandwidth, the first terminal device takes the first N reference signals as the first target reference signal, N being greater than or equal to 1.

[0018] The first terminal device can accumulate signals according to the reference density or the reference bandwidth in the reference period, which can solve the problem that the density or bandwidth of the received reference signal does not meet the measurement accuracy, and can ensure the measurement accuracy as much as possible and reduce the complexity of the design of the device and the system.

[0019] In a possible implementation, the method further includes that the first terminal device determines the length of the reference period; or the first terminal device receives first indication information from the second terminal device, the first indication information being used to indicate the length of the reference period.

[0020] The first terminal device can configure the length of the reference period by itself, or the length of the reference period can be configured by the second terminal device, or the length of the reference period can be configured by a network device, or the length of the reference period can be specified by a protocol, etc.

[0021] In a possible implementation, the first terminal device determines the length of the reference period, including: the first terminal device determines the length of the reference period according to a parameter of a data packet of the first service, the data packet of the first service being transmitted through the first link, the parameter of the data packet of the first service including an expected period length of the data packet of the first service, and / or including retransmission configuration information of the data packet of the first service.

[0022] The first terminal device determines the length of the reference period according to the parameter of the data packet related to the service, which can more accurately measure the channel quality according to the requirements of different services.

[0023] In a possible implementation, the length of the reference period satisfies:

[0024] T = min (first threshold, ceil (T packet × P1) ) ;

[0025] wherein T represents the length of the reference period, the first threshold is a constant, T packet represents the minimum expected period length of the data packet of the first service, P1 represents the retransmission configuration information of the first service, and ceil() represents an upward rounding operation.

[0026] If the length of the reference period is too short, and the reference signal is transmitted non-periodically, it is difficult to ensure that the reference signal can be received within one reference period, and if the length of the reference period is too long, the test frequency may not meet the requirements. Therefore, by setting the first threshold, the embodiments of the present application can keep the test frequency of the first terminal device moderate, which can meet the test requirements and ensure that the power consumption of the first terminal device is at a certain level, so as to avoid excessive power consumption. Of course, only one way of determining the length of the reference period is given here. In actual implementation, the way of determining the length of the reference period is not limited to this.

[0027] In a possible implementation, the value of P1 includes one or any combination of the following multiple items: when the first service does not perform retransmission, P1 = 2; when the first service performs blind retransmission, P1 = 2 / N1, N1 representing the number of times of blind retransmission of one data packet included in the first service; or, when the first service performs HARQ adaptive retransmission, P1 = 2 / N2, N2 representing the expected number of times of HARQ adaptive retransmission of one data packet included in the first service.

[0028] P1 represents the retransmission configuration information of the first service. When the first service does not perform retransmission or the retransmission manner adopted is different, the transmission of the first service is different, and accordingly, the length of the reference period can also change accordingly, so that the length of the determined reference period is more in line with the actual service situation, so as to more accurately measure the channel quality according to the needs of different services. For example, when the first service does not perform retransmission, P1 can be equal to 2, which is equivalent to making the length of the reference period twice the length of the minimum expected period of the data packet, that is, when the first service does not perform retransmission, the length of the reference period can be as long as possible, so that enough reference signals can be received within the reference period. However, the length of the reference period should not be too long, which will reduce the measurement frequency, so P1 is equal to 2 is a more moderate consideration, but the embodiments of the present application do not limit P1 to be equal to 2. For example, when the first service performs retransmission, P1 can be equal to 1 / 2 of the number of retransmissions of the first service. If the first service performs retransmission, more reference signals can be received in a shorter reference period, so the length of the reference period can be reduced to a certain extent to improve the measurement efficiency. However, the length of the reference period should not be too short, which may result in a lower probability of receiving reference signals, and will make the measurement frequency too high, resulting in a large power consumption of the terminal device, so P1 is equal to 1 / 2 of the number of retransmissions of the first service is a more moderate consideration, but the embodiments of the present application do not limit P1 to be equal to 1 / 2 of the number of retransmissions of the first service. Here, only some possible values of P1 are exemplified, and the specific values are not limited thereto.

[0029] In a possible implementation, the first terminal device obtains the synchronization indication information or the out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period, including: the first terminal device obtains the synchronization indication information or the out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period included in the first length, the at least one reference period being at least one reference period in which a reference signal is received in all reference periods in the first length.

[0030] The first terminal device can obtain synchronization indication information or out-of-sync indication information according to at least one target reference signal, so that the synchronization indication information or out-of-sync indication information obtained by the first terminal device is more accurate. The at least one reference period, for example, belongs to a first time length, and the at least one reference period can be a reference period in which a reference signal is received in the first time length, for example, an evaluation time length. Alternatively, it is stipulated that the first terminal device evaluates the first link after receiving a reference signal in P reference periods, P being an integer greater than or equal to 1, and if P is greater than 1, the P reference periods can be continuous or discontinuous. The difference between setting the evaluation time length is that the evaluation time length limits the total number of reference periods, but does not limit the number of reference periods in which a reference signal is actually received, while this way of not setting the evaluation time length limits the number of reference periods in which a reference signal is actually received. Regardless of which way, the number of target reference signals participating in the evaluation can be increased, so that the synchronization indication information or out-of-sync indication information obtained by the first terminal device is more accurate.

[0031] In a possible implementation, the method further includes: the first terminal device determines the first time length according to a time length of the reference period; or, the first terminal device receives second indication information from the second terminal device, the second indication information being used to indicate the first time length.

[0032] The first terminal device can configure the first time length by itself, or the first time length can also be configured by the second terminal device, or the first time length can also be configured by a network device, or the first time length can also be specified by a protocol, and the like.

[0033] In a possible implementation, the first terminal device obtains synchronization indication information of the first link according to at least one target reference signal in the at least one reference period included in the first time length; and the first terminal device determines the first time length according to a time length of the reference period, including:

[0034] The first terminal device determines that the first time length satisfies: L in = max(100, M in × T), L in denotes the first time length, M in denotes a number of periodic reference signals participating in synchronization measurement of the first link in one first time length when the synchronization measurement of the first link is performed according to the periodic reference signals, and T denotes a time length of the reference period; or

[0035] The first terminal device obtains out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period included in the first time length; and the first terminal device determines the first time length according to a time length of the reference period, including:

[0036] The first terminal device determines that the first time length satisfies: L out = max(200, M out × T), L out represents the first time length, M out represents a number of periodic reference signals participating in out-of-sync measurement of the first link within one first time length when the out-of-sync measurement is performed according to the periodic reference signals, and T represents a time length of the reference period.

[0037] 100 milliseconds (ms) is an evaluation time length when a link is measured for synchronization according to periodically transmitted reference signals. Since the reference signals in the embodiment of the present application are non-periodically transmitted, the arrival time of the reference signals cannot be guaranteed, and therefore the first time length of the synchronization measurement in the embodiment of the present application is selected as the maximum of 100 and M in × T, so as to guarantee that sufficient reference signals can be received within the first time length. The same is true for out-of-sync measurement. 200 ms is an evaluation time length when a link is measured for out-of-sync according to periodically transmitted reference signals. Since the reference signals in the embodiment of the present application are non-periodically transmitted, the arrival time of the reference signals cannot be guaranteed, and therefore the first time length of the out-of-sync measurement in the embodiment of the present application is selected as the maximum of 200 and M out × T, so as to guarantee that sufficient reference signals can be received within the first time length.

[0038] In a possible implementation, the first terminal device determines the first time length according to the time length of the reference period, including: the first terminal device determines the first time length according to the time length of the reference period and a first parameter, the first parameter including reference density and / or reference bandwidth, the reference density being used to determine the target reference signal, and the reference bandwidth being used to determine the target reference signal.

[0039] By configuring a time length of a reference period, reference density, or reference bandwidth, and the like, link evaluation parameters, signal accumulation can be performed according to the reference density or the reference bandwidth within the reference period, a problem that the density or the bandwidth of the received reference signals does not satisfy measurement accuracy, and the like can be solved, the measurement accuracy is guaranteed as much as possible, and the complexity of device and system design is reduced.

[0040] In a possible implementation, the first terminal device determines the first time length according to the reference period and a parameter related to reference density, including:

[0041] The first time length is used for obtaining the synchronization indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P2) × T), L in represents the first time length, T represents a time length of the reference period, M in represents a number of reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured for synchronization according to the periodic reference signals, and P2 represents a parameter related to the reference density; or

[0042] The first time length is used for obtaining the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P2) × T), L out represents the first time length, T represents a time length of the reference period, M out represents a number of reference signals participating in out-of-sync evaluation in one of the first time lengths when the first link is evaluated for out-of-sync according to the periodic reference signals, and P2 represents a parameter related to the reference density.

[0043] If the first time length is too short, and the reference signals are transmitted aperiodically, it is difficult to ensure that the reference signals can be received in the first time length, and if the first time length is too long, the test frequency may not meet the requirements. Therefore, by setting the second threshold, the embodiments of the present application can keep the test frequency of the first terminal device moderate, which can meet the test requirements and ensure that the power consumption of the first terminal device is at a certain level, so as to avoid excessive power consumption. Moreover, the first time length can be related to the reference density, which also solves the problem that the density of the received reference signals does not meet the measurement accuracy.

[0044] In a possible implementation, the first terminal device determines the first time length according to the reference period and a parameter related to a reference bandwidth, including:

[0045] The first time length is used for obtaining the synchronization indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P3) × T), L in represents the first time length, T represents a time length of the reference period, M in represents a number of reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured for synchronization according to the periodic reference signals, and P3 represents a parameter related to the reference bandwidth; or

[0046] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out x P3) x T), L out represents the first time length, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement in one first time length when the first link is measured according to the periodic reference signal, and P3 represents a parameter related to the reference bandwidth.

[0047] If the first time length is too short, and the reference signal is transmitted non-periodically, it is difficult to ensure that the reference signal can be received within the first time length, and if the first time length is too long, the test frequency may not meet the requirements. Therefore, by setting the second threshold, the embodiments of the present application can keep the test frequency of the first terminal device moderate, which can meet the test requirements and ensure that the power consumption of the first terminal device is at a certain level, so as to avoid excessive power consumption. Moreover, the first time length can be related to the reference density, which also solves the problem that the bandwidth of the received reference signal does not meet the measurement accuracy.

[0048] In a possible implementation, the first terminal device determines the first time length according to the reference period, the transmission related to the reference density, and the parameter related to the reference bandwidth, comprising:

[0049] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in x P2 x P3) x T), L in represents the first time length, T represents the reference period, M in represents the number of reference signals participating in synchronization measurement in one first time length when the first link is measured according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth; or

[0050] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M out x P2 x P3) x T), L in represents the first time length, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement in one first time length when the first link is measured according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth.

[0051] If the first time length is too short and the reference signal is non-periodically transmitted, it is difficult to ensure that the reference signal can be received within the first time length, and if the first time length is too long, the test frequency can not meet the requirements. Therefore, by setting the second threshold, the embodiments of the present application can keep the test frequency of the first terminal device moderate, which can meet the test requirements and ensure that the power consumption of the first terminal device is at a certain level, so as to avoid excessive power consumption. Moreover, the first time length can be related to the reference density, which also solves the problem that the density and bandwidth of the received reference signal do not meet the measurement accuracy.

[0052] As described above, only several calculation methods of the first time length are given, and the first time length can also be determined by other methods, which are not limited.

[0053] In a possible implementation, the method further includes: determining, by the first terminal device, validity information, the validity information being used to indicate validity of the synchronization indication information or validity of the out-of-sync indication information, wherein the more the number of the at least one reference period is, the higher the validity of the synchronization indication information or the out-of-sync indication information is.

[0054] After the high layer of the first terminal device obtains the synchronization indication information or the out-of-sync indication information and the validity information, the reliability of the evaluation information can be determined through the validity information, so as to determine whether the link fails according to the evaluation information. In this way, the reliability of the link measurement can be improved. The evaluation information includes the synchronization indication information or the out-of-sync indication information.

[0055] In a possible implementation, the first terminal device maintains a first timer, and the first timer is used to, if no reference signal is received within a timing time length of the first timer, determine, when the first timer times out, that the link fails.

[0056] The first terminal device is likely to not receive the reference signal for a long time, for example, when the link fails, the first terminal device can not receive the reference signal for a long time. Then, in order to avoid the first terminal device from continuously waiting, the first terminal device can also maintain a first timer in the embodiments of the present application. If the first terminal device does not receive the reference signal for wireless link measurement within the timing time length of the first timer, the first terminal device can directly determine that the first link fails when the first timer times out. In this way, the terminal device can avoid continuous waiting and can determine the link failure in a timely manner.

[0057] In a second aspect, a second link measurement method is provided, which includes: a first terminal device not receiving a reference signal from a second terminal device in a third time length, the reference signal being used by the first terminal device to measure a first link between the first terminal device and the second terminal device; and the first terminal device determining that the first link fails.

[0058] The method can be performed by a second communication device, which can be a communication apparatus or a communication device capable of supporting the communication apparatus to implement the functions required by the method, such as a chip system. For example, the second communication device is the first terminal device. For example, the first terminal device is a first terminal apparatus, or a chip system arranged in the first terminal apparatus to implement the functions of the terminal apparatus, or other components for implementing the functions of the first terminal apparatus.

[0059] The first terminal device is likely to not receive the reference signal for a long time, for example, when the link fails. Then, in order to avoid the first terminal device from continuously waiting, in the embodiments of the present application, the first terminal device can maintain a first timer. If the first terminal device does not receive the reference signal for wireless link measurement within the timing length of the first timer, the first terminal device can directly determine that the first link fails when the first timer times out. In this way, the terminal apparatus can be prevented from continuously waiting, and the link failure can be determined as timely as possible.

[0060] In a third aspect, a first link evaluation method is provided, which includes: a first terminal device obtaining a channel busy ratio in a second time length according to a number of first type channels and a total number of channels, the first type channels including channels with a signal strength greater than or equal to a first threshold in the second time length; and the first terminal device performing synchronous evaluation or out-of-sync evaluation on a link between the first terminal device and a second terminal device according to the channel busy ratio.

[0061] The method can be performed by a third communication device, which can be a communication apparatus or a communication device capable of supporting the communication apparatus to implement the functions required by the method, such as a chip system. For example, the second communication device is the first terminal device. For example, the first terminal device is a first terminal apparatus, or a chip system arranged in the first terminal apparatus to implement the functions of the terminal apparatus, or other components for implementing the functions of the first terminal apparatus.

[0062] In the embodiments of the present application, the link can be evaluated according to the channel busy ratio, which is simple and reduces the complexity of design and implementation.

[0063] In a possible implementation, the first terminal device performs synchronization evaluation or out-of-sync evaluation on a link between the first terminal device and the second terminal device according to the channel busy ratio, including: when the channel busy ratio is greater than or equal to a second threshold, the first terminal device determines that the link is out-of-sync; or when the channel busy ratio is less than or equal to a third threshold, the first terminal device determines that the link is in-sync.

[0064] The second threshold can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the second threshold can also be configured by a network device and informed to the first terminal device. Alternatively, the second threshold can also be specified by a protocol. For example, the second threshold is 70%, or can also be other values. Similarly, the third threshold can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the third threshold can also be configured by a network device and informed to the first terminal device. Alternatively, the third threshold can also be specified by a protocol. For example, the third threshold is 40%, or can also be other values.

[0065] In a fourth aspect, a second link evaluation method is provided, including: a first terminal device updates a counter according to a demodulation result of a first signal from a second terminal device, where an initial value of the counter is greater than 0; and the first terminal device determines whether a link with the second terminal device fails according to a value of the counter.

[0066] The method can be performed by a fourth communication device, which can be a communication device or a communication device capable of supporting functions required by the communication device to implement the method, such as a chip system. Illustratively, the second communication device is a first terminal device. Illustratively, the first terminal device is a first terminal device, or a chip system provided in the first terminal device and used to implement functions of the terminal device, or other components used to implement functions of the first terminal device.

[0067] In the embodiments of the present application, the first terminal device can evaluate the link according to a demodulation result of a signal from the second terminal device, which is equivalent to evaluating the link using a decoding result of PSSCH / PSCCH, thereby reducing complexity in design and implementation.

[0068] In a possible implementation, the first signal is a control signal, and the first terminal device updates the counter according to a demodulation result of the first signal from the second terminal device, including: the first terminal device successfully demodulates the first signal, and the first terminal device increases a value of the counter by a first value; or the first terminal device misses the first signal, and the first terminal device decreases the value of the counter by a second value.

[0069] In a possible implementation, the first signal is a data signal, and the first signal is initial transmission data, and the first terminal device updates the counter according to a demodulation result of the first signal from the second terminal device, including: the first terminal device successfully demodulates the first signal, and the first terminal device increases a value of the counter by a third value; or the first terminal device fails to demodulate the first signal, and the first terminal device decreases the value of the counter by a fourth value.

[0070] In a possible implementation, the first signal is a data signal, and the first signal is retransmission data, and the first terminal device updates the counter according to a demodulation result of the first signal from the second terminal device, including: the first terminal device successfully demodulates the first signal, and the first terminal device increases a value of the counter by a fifth value; or the first terminal device fails to demodulate the first signal, and the first terminal device decreases the value of the counter by a sixth value.

[0071] The above gives several ways for the first terminal device to update the counter.

[0072] In a possible implementation, the first terminal device determines whether a link between the first terminal device and the second terminal device fails according to a value of the counter, including: when the value of the counter is 0, the first terminal device determines that the link fails.

[0073] If the initial value of the counter is greater than 0, when the value of the counter is 0, the first terminal device can determine that the link fails. By maintaining the counter, the link can be evaluated in a simple way.

[0074] In a fifth aspect, a third link evaluation method is provided, including: a second terminal device receives feedback information from a first terminal device; and the second terminal device obtains synchronization indication information or out-of-sync indication information of a link according to the received feedback information, the link being a link between the first terminal device and the second terminal device.

[0075] The method can be performed by a fifth communication device, which can be a communication apparatus or a communication device, such as a chip system, capable of supporting the functions required by the communication apparatus to implement the method. Illustratively, the second communication device is a first terminal device. Illustratively, the first terminal device is a first terminal apparatus, or a chip system provided in the first terminal apparatus to implement the functions of the terminal apparatus, or other components to implement the functions of the first terminal apparatus.

[0076] In the embodiments of the present application, the second terminal device can evaluate the link, so that the link can be evaluated by either the sending end or the receiving end of data, which is more flexible. Moreover, the evaluation method provided in the embodiments of the present application is simple and easy to implement.

[0077] In a possible implementation, the second terminal device obtains synchronization indication information or out-of-sync indication information of the link according to the received feedback information, including:

[0078] When N1 / N is greater than a first threshold, the second terminal device obtains the synchronization indication information, or when N1 / N is less than a second threshold, the second terminal device obtains the out-of-sync indication information, where N1 represents the number of positive acknowledgments received by the second terminal device within a first time length, and N represents the total number of HARQ acknowledgment information expected to be received by the second terminal device within the first time length; or

[0079] When N2 / N is less than a third threshold, the second terminal device obtains the synchronization indication information, or when N2 / N is greater than a fourth threshold, the second terminal device obtains the out-of-sync indication information, where N2 represents the number of negative acknowledgments received by the second terminal device within a first time length, and N represents the total number of HARQ acknowledgment information expected to be received by the second terminal device within the first time length; or

[0080] When N2 / N1 is less than a fifth threshold, the second terminal device obtains the synchronization indication information, or when N2 / N is greater than a sixth threshold, the second terminal device obtains the out-of-sync indication information, where N2 represents the number of negative acknowledgments received by the second terminal device within a first time length, and N1 represents the number of positive acknowledgments received by the second terminal device within the first time length.

[0081] Several ways for the second terminal device to evaluate the link are given. These ways are only examples, and the second terminal device can also use other methods to evaluate the link.

[0082] In a possible implementation, the method further includes: the second terminal device determines whether the link fails according to the synchronization indication information or the out-of-sync indication information.

[0083] After obtaining the synchronization indication information or the out-of-sync indication information, the first terminal device can determine whether the first link fails, and if the first link fails, the first terminal device can perform subsequent corresponding processing.

[0084] In a sixth aspect, a communication device is provided, for example, the communication device is the first terminal device as described above. The first terminal device is configured to perform the method in the first aspect or any possible implementation. Specifically, the first terminal device can include a module configured to perform the method in the first aspect or any possible implementation, for example, a processing module and a transceiver module. Illustratively, the first terminal device is a communication device. Illustratively, the communication device is a terminal device. Wherein,

[0085] The transceiver module is configured to receive at least one reference signal from the second terminal device in a first reference period, the at least one reference signal being aperiodically transmitted.

[0086] The processing module is configured to determine a first target reference signal in the first reference period according to the at least one reference signal.

[0087] The processing module is further configured to obtain synchronization indication information or out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period, the first link being a link between the first terminal device and the second terminal device, the at least one reference period including the first reference period, and the at least one target reference signal including the first target reference signal.

[0088] In a possible implementation, the processing module is further configured to determine whether the first link fails according to the synchronization indication information or the out-of-sync indication information.

[0089] In a possible implementation, the processing module is configured to determine the first target reference signal in the first reference period according to the at least one reference signal by determining one of the at least one reference signal as the first target reference signal, or combining part or all of the at least one reference signal to obtain the first target reference signal.

[0090] In a possible implementation, the processing module is configured to determine the first target reference signal in the first reference period according to the at least one reference signal by:

[0091] In a case where a cumulative density of a first N reference signals in the at least one reference signal is greater than or equal to a reference density, the first N reference signals are taken as the first target reference signals, N is greater than or equal to 1, wherein the density of a reference signal is a number of frequency domain units carrying the reference signal in a bandwidth occupied by the reference signal, and the cumulative density of the reference signal is a sum of densities of one or more reference signals; or,

[0092] In a case where a cumulative bandwidth of a first N reference signals in the at least one reference signal is greater than or equal to a reference bandwidth, the first N reference signals are taken as the first target reference signals, N is greater than or equal to 1.

[0093] In a possible implementation, the processing module is further configured to determine a time length of the reference period; or,

[0094] The transceiving module is further configured to receive, from the second terminal device, first indication information, the first indication information being used to indicate the time length of the reference period.

[0095] In a possible implementation, the processing module is configured to determine the time length of the reference period according to a parameter of a data packet of a first service, the data packet of the first service being transmitted through the first link, the parameter of the data packet of the first service including an expected period time length of the data packet of the first service and / or including retransmission configuration information of the data packet of the first service.

[0096] In a possible implementation, the time length of the reference period satisfies:

[0097] T = min (first threshold, ceil (T packet × P1)) ;

[0098] wherein T represents the time length of the reference period, the first threshold is a constant, T packet represents a minimum expected period time length of the data packet of the first service, P1 represents the retransmission configuration information of the first service, and ceil() represents an upward rounding operation.

[0099] In a possible implementation, a value of P1 includes one or any combination of the following multiple items: when the first service does not perform retransmission, P1 = 2; when the first service performs blind retransmission, P1 = 2 / N1, N1 represents a number of times of blind retransmission of one data packet included in the first service; or when the first service performs HARQ adaptive retransmission, P1 = 2 / N2, N2 represents an expected number of times of HARQ adaptive retransmission of one data packet included in the first service.

[0100] In a possible implementation, the processing module is configured to obtain the synchronization indication information or the out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period in the first time length in the following manner: obtaining the synchronization indication information or the out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period included in the first time length, the at least one reference period being at least one reference period in which a reference signal is received among all reference periods in the first time length.

[0101] In a possible implementation, the processing module is further configured to determine the first time length according to a time length of the reference period, or the transceiver module is further configured to receive second indication information from the second terminal device, the second indication information being used to indicate the first time length.

[0102] In a possible implementation, the processing module obtains the synchronization indication information of the first link according to at least one target reference signal in at least one reference period included in the first time length; and the processing module is configured to determine the first time length according to a time length of the reference period in the following manner:

[0103] determining that the first time length satisfies: L in = max(100, M in × T), L in denotes the first time length, M in denotes a number of periodic reference signals participating in synchronization measurement of the first link within one first time length when the synchronization measurement of the first link is performed according to the periodic reference signals, and T denotes a time length of the reference period.

[0104] The processing module obtains the out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period included in the first time length; and the processing module is configured to determine the first time length according to a time length of the reference period in the following manner:

[0105] determining that the first time length satisfies: L out = max(200, M out × T), L out denotes the first time length, M out denotes a number of periodic reference signals participating in out-of-sync measurement of the first link within one first time length when the out-of-sync measurement of the first link is performed according to the periodic reference signals, and T denotes a time length of the reference period.

[0106] In a possible implementation, the processing module is configured to determine the first time length according to the time length of the reference period by: determining the first time length according to the time length of the reference period and a first parameter, the first parameter comprising a reference density and / or a reference bandwidth, the reference density being used to determine the target reference signal, and the reference bandwidth being used to determine the target reference signal.

[0107] In a possible implementation, the processing module is configured to determine the first time length according to the reference period and a parameter related to a reference density by:

[0108] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P2) × T), L in represents the first time length, T represents the time length of the reference period, M in represents the number of reference signals participating in the in-sync measurement in one first time length when the first link is measured in-sync according to the periodic reference signal, and P2 represents the parameter related to the reference density; or

[0109] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P2) × T), L out represents the first time length, T represents the time length of the reference period, M out represents the number of reference signals participating in the out-of-sync measurement in one first time length when the first link is measured out-of-sync according to the periodic reference signal, and P2 represents the parameter related to the reference density.

[0110] In a possible implementation, the processing module is configured to determine the first time length according to the reference period and a parameter related to a reference bandwidth by:

[0111] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P3) × T), L in represents the first time length, T represents the reference period, M in represents the number of reference signals participating in the in-sync measurement in one first time length when the first link is measured in-sync according to the periodic reference signal, and P3 represents the parameter related to the reference bandwidth; or

[0112] The first time length is used for obtaining the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P3) × T), L out represents the first time length, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured according to the periodic reference signal, and P3 represents a parameter related to the reference bandwidth.

[0113] In a possible implementation, the processing module is configured to determine the first time length according to the reference period, the transmission related to the reference density, and the parameter related to the reference bandwidth in the following manner:

[0114] The first time length is used for obtaining the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P2 × P3) × T) L in represents the first time length, T represents the reference period, M in represents the number of reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth; or

[0115] The first time length is used for obtaining the out-of-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M out × P2 × P3) × T) L in represents the first time length, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth.

[0116] In a possible implementation, the processing module is further configured to determine validity information, the validity information being used for indicating validity of the in-sync indication information or validity of the out-of-sync indication information, wherein the more the number of the at least one reference period is, the higher the validity of the in-sync indication information or the out-of-sync indication information is.

[0117] In a possible implementation, the processing module is further configured to maintain a first timer, and determine that the link failure occurs when the first timer expires if no reference signal is received within a time duration of the first timer.

[0118] For the technical effects of the sixth aspect or various possible implementations, reference can be made to the introduction of the technical effects of the first aspect or the corresponding implementation of the first aspect.

[0119] In a seventh aspect, a communication apparatus, for example, the first terminal device as described above, is provided. The first terminal device is configured to perform the method in the second aspect or any possible implementation. Specifically, the first terminal device can include a module configured to perform the method in the second aspect or any possible implementation, for example, a processing module and a transceiver module. Illustratively, the first terminal device is a communication device. Illustratively, the communication device is a terminal device. Wherein,

[0120] The processing module is configured to determine that the transceiver module does not receive a reference signal from a second terminal device within a third time duration, the reference signal being used for the first terminal device to measure a first link between the first terminal device and the second terminal device;

[0121] The processing module is further configured to determine that the first link fails.

[0122] For the technical effects of the seventh aspect or various possible implementations, reference can be made to the introduction of the technical effects of the second aspect or the corresponding implementation of the second aspect.

[0123] In an eighth aspect, a communication apparatus, for example, the first terminal device as described above, is provided. The first terminal device is configured to perform the method in the third aspect or any possible implementation. Specifically, the first terminal device can include a module configured to perform the method in the third aspect or any possible implementation, for example, a processing module and a transceiver module. Illustratively, the first terminal device is a communication device. Illustratively, the communication device is a terminal device. Wherein,

[0124] The processing module is configured to obtain a channel busy ratio within a second time duration according to a number of first type channels and a total number of channels between the first terminal device and the second terminal device, the first type channels including channels with a signal strength greater than or equal to a first threshold within the second time duration.

[0125] The processing module is further configured to perform synchronization evaluation or out-of-sync evaluation on a link between the first terminal device and the second terminal device according to the channel busy ratio.

[0126] In a possible implementation, the processing module is configured to perform synchronization evaluation or out-of-sync evaluation on the link between the first terminal device and the second terminal device according to the channel busy ratio in the following manner: determining that the link is out-of-sync when the channel busy ratio is greater than or equal to a second threshold; or determining that the link is in-sync when the channel busy ratio is less than or equal to a third threshold.

[0127] For the technical effects of the eighth aspect or the various possible implementations, reference can be made to the description of the technical effects of the third aspect or the corresponding implementation of the third aspect.

[0128] The ninth aspect provides a communication device, for example, the communication device is the first terminal device as described above. The first terminal device is configured to perform the method in the fourth aspect or any possible implementation. Specifically, the first terminal device can include a module for performing the method in the fourth aspect or any possible implementation, for example, including a processing module and a transceiver module. Illustratively, the first terminal device is a communication device. Illustratively, the communication device is a terminal device. Wherein,

[0129] The processing module is configured to update a counter according to the demodulation of the first signal from the second terminal device, and an initial value of the counter is greater than 0.

[0130] The processing module is further configured to determine whether the link with the second terminal device fails according to a value of the counter.

[0131] In a possible implementation, the first signal is a control signal, and the processing module is configured to update the counter according to the demodulation of the first signal from the second terminal device in the following manner: increasing a value of the counter by a first value when the first signal is successfully demodulated; or decreasing the value of the counter by a second value when the first signal is missed.

[0132] In a possible implementation, the first signal is a data signal, and the first signal is initial transmission data, and the processing module is configured to update the counter according to the demodulation of the first signal from the second terminal device in the following manner: increasing a value of the counter by a third value when the first signal is successfully demodulated; or decreasing the value of the counter by a fourth value when the first signal is unsuccessfully demodulated.

[0133] In a possible implementation, the first signal is a data signal, and the first signal is retransmitted data, and the processing module is configured to update the counter according to demodulation of the first signal from the second terminal device in the following manner: when the first signal is successfully demodulated, increasing the value of the counter by a fifth value; or when the first signal is unsuccessfully demodulated, decreasing the value of the counter by a sixth value.

[0134] In a possible implementation, the processing module is configured to determine whether the link with the second terminal device fails according to the value of the counter in the following manner: when the value of the counter is 0, determining that the link fails.

[0135] For the technical effects of the ninth aspect or the various possible implementations, reference can be made to the introduction of the technical effects of the fourth aspect or the corresponding implementation of the fourth aspect.

[0136] The tenth aspect provides a communication device, for example, the communication device is the second terminal device as described above. The first terminal device is configured to perform the method in the fifth aspect or any possible implementation. Specifically, the second terminal device can include a module configured to perform the method in the fifth aspect or any possible implementation, for example, a processing module and a transceiver module. Illustratively, the second terminal device is a communication device. Illustratively, the communication device is a terminal device. Wherein,

[0137] The transceiver module is configured to receive feedback information from the first terminal device.

[0138] The processing module is configured to obtain synchronization indication information or out-of-step indication information of a link according to the received feedback information, the link being a link between the first terminal device and the second terminal device.

[0139] In a possible implementation, the processing module is configured to obtain the synchronization indication information or the out-of-step indication information of the link according to the received feedback information in the following manner:

[0140] When N1 / N is greater than a first threshold, the synchronization indication information is obtained, or when N1 / N is less than a second threshold, the out-of-step indication information is obtained, wherein N1 represents a number of positive acknowledgments received by the second terminal device within a first time length, and N represents a total number of HARQ acknowledgment information expected to be received by the second terminal device within the first time length; or

[0141] obtaining the synchronization indication information when N2 / N is less than a third threshold, or obtaining the out-of-synchronization indication information when N2 / N is greater than a fourth threshold, wherein N2 represents a number of negative acknowledgements received by the second terminal device within a first time length, and N represents a total number of HARQ acknowledgement information expected to be received by the second terminal device within the first time length; or

[0142] obtaining the synchronization indication information when N2 / N1 is less than a fifth threshold, or obtaining the out-of-synchronization indication information when N2 / N is greater than a sixth threshold, wherein N2 represents a number of negative acknowledgements received by the second terminal device within a first time length, and N1 represents a number of positive acknowledgements received by the second terminal device within the first time length.

[0143] In a possible implementation, the processing module is further configured to determine whether the link fails according to the synchronization indication information or the out-of-synchronization indication information.

[0144] As to the technical effects of the tenth aspect or various possible implementation manners, reference can be made to the introduction of the technical effects of the fifth aspect or the corresponding implementation manners of the fifth aspect.

[0145] The eleventh aspect provides a communication device, for example, the first terminal device as described above. The communication device includes a processor and a transceiver, which are coupled to each other, and are configured to implement the method described in the first aspect or various possible implementation manners. Exemplarily, the communication device is a chip arranged in a communication device. Exemplarily, the communication device is a terminal device. The transceiver is implemented by, for example, an antenna, a feed line, a codec, and the like in the communication device, or if the communication device is a chip arranged in the communication device, the transceiver is, for example, a communication interface in the chip, which is connected with a radio frequency transceiving component in the communication device to implement the transceiving of information through the radio frequency transceiving component. Wherein,

[0146] the transceiver is configured to receive at least one reference signal from a second terminal device within a first reference period, the at least one reference signal being aperiodically transmitted;

[0147] the processor is configured to determine a first target reference signal in the first reference period according to the at least one reference signal;

[0148] the processor is further configured to obtain synchronization indication information or out-of-synchronization indication information of a first link according to at least one target reference signal in at least one reference period, the first link being a link between the first terminal device and the second terminal device, the at least one reference period including the first reference period, and the at least one target reference signal including the first target reference signal.

[0149] In a possible implementation, the processor is further configured to determine whether the first link fails according to the synchronization indication information or the out-of-sync indication information.

[0150] In a possible implementation, the processor is configured to determine the first target reference signal in the first reference period according to the at least one reference signal in the following manner: determining one reference signal in the at least one reference signal as the first target reference signal; or, merging part or all of the at least one reference signal to obtain the first target reference signal.

[0151] In a possible implementation, the processor is configured to determine the first target reference signal in the first reference period according to the at least one reference signal in the following manner:

[0152] in a case where a cumulative density of the first N reference signals in the at least one reference signal is greater than or equal to a reference density, taking the first N reference signals as the first target reference signal, N being greater than or equal to 1, wherein the density of a reference signal is a number of frequency domain units carrying the reference signal in a bandwidth occupied by the reference signal, and the cumulative density of the reference signal is a sum of densities of one or more reference signals; or,

[0153] in a case where a cumulative bandwidth of the first N reference signals in the at least one reference signal is greater than or equal to a reference bandwidth, taking the first N reference signals as the first target reference signal, N being greater than or equal to 1.

[0154] In a possible implementation, the processor is further configured to determine a time length of the reference period; or the transceiver is further configured to receive, from the second terminal device, first indication information, the first indication information being used to indicate the time length of the reference period.

[0155] In a possible implementation, the processor is configured to determine the time length of the reference period in the following manner: determining the time length of the reference period according to a parameter of a data packet of a first service, the data packet of the first service being transmitted through the first link, the parameter of the data packet of the first service including an expected period time length of the data packet of the first service, and / or including retransmission configuration information of the data packet of the first service.

[0156] In a possible implementation, the time length of the reference period satisfies:

[0157] T = min(first threshold, ceil(T packet × P1));

[0158] Wherein, T represents the duration of the reference period, the first threshold is a constant, and T packet represents the minimum expected cycle duration of the data packet of the first service, P1 represents the retransmission configuration information of the first service, and ceil() represents the rounding-up operation.

[0159] In one possible embodiment, the value of P1 includes one or any combination of the following: when the first service is not retransmitted, P1=2; when the first service is blindly retransmitted, P1=2 / N1, N1 represents the number of times a data packet included in the first service is blindly retransmitted; or, when the first service is HARQ adaptively retransmitted, P1=2 / N2, N2 represents the expected number of times a data packet included in the first service is HARQ adaptively retransmitted.

[0160] In one possible embodiment, the processor is used to obtain synchronization indication information or out-of-sync indication information of the first link based on at least one target reference signal in at least one reference period in the following manner: obtaining synchronization indication information or out-of-sync indication information of the first link based on at least one target reference signal in the at least one reference period included in the first time length, where the at least one reference period is at least one reference period in which a reference signal is received among all reference periods in the first time length.

[0161] In a possible implementation, the processor is further configured to determine the first duration based on the duration of the reference period; or the transceiver is further configured to receive second indication information from the second terminal device, where the second indication information is used to indicate the first duration.

[0162] In one possible implementation, the processor obtains synchronization indication information of the first link based on at least one target reference signal in the at least one reference period included in the first duration; and the processor is configured to determine the first duration based on the duration of the reference period in the following manner:

[0163] Determine that the first duration satisfies: L in =max(100,M in ×T), L in Indicates the first duration, M in represents the number of periodic reference signals participating in the synchronization measurement within the first duration when the synchronization measurement is performed on the first link according to the periodic reference signal, and T represents the duration of the reference period; or

[0164] The processor obtains out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period included in the first time length; and the processor is configured to determine the first time length according to a time length of the reference period in the following manner:

[0165] The first time length satisfies: L out = max(200, M out × T), L out denotes the first time length, M out denotes a number of periodic reference signals participating in out-of-sync measurement of the first link in one first time length when the out-of-sync measurement is performed on the first link according to the periodic reference signals, and T denotes a time length of the reference period.

[0166] In a possible implementation, the processor is configured to determine the first time length according to a time length of the reference period and a first parameter in the following manner: the first time length is determined according to the time length of the reference period and the first parameter, the first parameter including a reference density and / or a reference bandwidth, the reference density being used to determine the target reference signal, and the reference bandwidth being used to determine the target reference signal.

[0167] In a possible implementation, the processor is configured to determine the first time length according to the reference period and a parameter related to the reference density in the following manner:

[0168] The first time length is used to obtain the synchronization indication information, and the first time length satisfies the following formula: L in = max(200, ceil(M in × P2) × T), L in denotes the first time length, T denotes a time length of the reference period, M in denotes a number of reference signals participating in synchronization measurement of the first link in one first time length when the synchronization measurement is performed on the first link according to the periodic reference signals, and P2 denotes a parameter related to the reference density; or

[0169] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max(200, ceil(M out × P2) × T), L out denotes the first time length, T denotes a time length of the reference period, M out denotes a number of reference signals participating in out-of-sync measurement of the first link in one first time length when the out-of-sync measurement is performed on the first link according to the periodic reference signals, and P2 denotes a parameter related to the reference density.

[0170] In a possible implementation, the processor is configured to determine the first time length according to the reference period and a parameter related to a reference bandwidth in the following manner:

[0171] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P3) × T), L in represents the first time length, T represents the reference period, M in represents the number of reference signals participating in synchronization measurement in one first time length when performing synchronization measurement on the first link according to periodic reference signals, and P3 represents the parameter related to the reference bandwidth; or

[0172] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P3) × T), L out represents the first time length, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement in one first time length when performing synchronization measurement on the first link according to periodic reference signals, and P3 represents the parameter related to the reference bandwidth.

[0173] In a possible implementation, the processor is configured to determine the first time length according to the reference period, transmission related to a reference density, and a parameter related to a reference bandwidth in the following manner:

[0174] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P2 × P3) × T) L in represents the first time length, T represents the reference period, M in represents the number of reference signals participating in synchronization measurement in one first time length when performing synchronization measurement on the first link according to periodic reference signals, P2 represents the parameter related to the reference density, and P3 represents the parameter related to the reference bandwidth; or

[0175] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M out × P2 × P3) × T) L in represents the first time length, T represents the reference period, Mout P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth.

[0176] In a possible implementation, the processor is further configured to determine validity information, the validity information being used to indicate validity of the in-sync indication information or validity of the out-of-sync indication information, wherein the more the number of the at least one reference period, the higher the validity of the in-sync indication information or the out-of-sync indication information.

[0177] In a possible implementation, the processor is further configured to maintain a first timer, the first timer being used to determine the link failure when no reference signal is received within a timing duration of the first timer.

[0178] As to the technical effects of the eleventh aspect or various possible implementations, reference can be made to the introduction of the technical effects of the first aspect or corresponding implementations.

[0179] A twelfth aspect provides a communication apparatus, for example, the first terminal apparatus as described above. The communication apparatus includes a processor and a transceiver, which are coupled to each other, and are configured to implement the method described in the second aspect or various possible implementations. Illustratively, the communication apparatus is a chip arranged in a communication device. Illustratively, the communication device is a terminal device. Wherein, the transceiver is implemented by, for example, an antenna, a feeder, a codec and the like in the communication device, or if the communication apparatus is a chip arranged in the communication device, the transceiver is, for example, a communication interface in the chip, which is connected with a radio frequency transceiving component in the communication device to realize the transceiving of information through the radio frequency transceiving component. Wherein,

[0180] The processor is configured to determine that the transceiver does not receive a reference signal from a second terminal apparatus within a third time duration, the reference signal being used for the first terminal apparatus to measure a first link between the first terminal apparatus and the second terminal apparatus.

[0181] The processor is further configured to determine the first link failure.

[0182] As to the technical effects of the twelfth aspect or various possible implementations, reference can be made to the introduction of the technical effects of the second aspect or corresponding implementations.

[0183] In a thirteenth aspect, a communication apparatus, for example, a first terminal device as described above, is provided. The communication apparatus includes a processor and a transceiver coupled to each other, configured to implement the method described in the third aspect or various possible implementations. Exemplarily, the communication apparatus is a chip disposed in a communication device. Exemplarily, the communication device is a terminal device. The transceiver is implemented by, for example, an antenna, a feed line, a codec, and the like in the communication device, or if the communication apparatus is a chip disposed in the communication device, the transceiver is, for example, a communication interface in the chip connected to a radio frequency transceiving component in the communication device to implement the transceiving of information through the radio frequency transceiving component. Wherein,

[0184] obtain, according to a number of the first type of channels and a total number of channels between the second terminal device, a channel busy ratio in a second time duration, the first type of channels including channels with a signal strength greater than or equal to a first threshold in the second time duration;

[0185] synchronously evaluate or out-of-sync evaluate a link between the first terminal device and the second terminal device according to the channel busy ratio.

[0186] In a possible implementation, the processor is configured to synchronously evaluate or out-of-sync evaluate the link between the first terminal device and the second terminal device according to the channel busy ratio by: determining that the link is out-of-sync when the channel busy ratio is greater than or equal to a second threshold; or determining that the link is in-sync when the channel busy ratio is less than or equal to a third threshold.

[0187] As for the technical effects of the thirteenth aspect or various possible implementations, reference can be made to the introduction of the technical effects of the third aspect or corresponding implementations.

[0188] In a fourteenth aspect, a communication apparatus, for example, a first terminal device as described above, is provided. The communication apparatus includes a processor and a transceiver coupled to each other, configured to implement the method described in the fourth aspect or various possible implementations. Exemplarily, the communication apparatus is a chip disposed in a communication device. Exemplarily, the communication device is a terminal device. The transceiver is implemented by, for example, an antenna, a feed line, a codec, and the like in the communication device, or if the communication apparatus is a chip disposed in the communication device, the transceiver is, for example, a communication interface in the chip connected to a radio frequency transceiving component in the communication device to implement the transceiving of information through the radio frequency transceiving component. Wherein,

[0189] The processor is configured to update the counter according to a demodulation result of the first signal from the second terminal device, wherein an initial value of the counter is greater than 0.

[0190] The processor is further configured to determine whether a link between the second terminal device and the terminal device fails according to a value of the counter.

[0191] In a possible implementation, the first signal is a control signal, and the processor is configured to update the counter according to a demodulation result of the first signal from the second terminal device by: increasing a value of the counter by a first value when the first signal is successfully demodulated; or decreasing the value of the counter by a second value when the first signal is missed.

[0192] In a possible implementation, the first signal is a data signal, and the first signal is initial transmission data, and the processor is configured to update the counter according to a demodulation result of the first signal from the second terminal device by: increasing a value of the counter by a third value when the first signal is successfully demodulated; or decreasing the value of the counter by a fourth value when the first signal is unsuccessfully demodulated.

[0193] In a possible implementation, the first signal is a data signal, and the first signal is retransmission data, and the processor is configured to update the counter according to a demodulation result of the first signal from the second terminal device by: increasing a value of the counter by a fifth value when the first signal is successfully demodulated; or decreasing the value of the counter by a sixth value when the first signal is unsuccessfully demodulated.

[0194] In a possible implementation, the processor is configured to determine whether a link between the second terminal device and the terminal device fails according to a value of the counter by: determining that the link fails when the value of the counter is 0.

[0195] As to the technical effects of the fourteenth aspect or various possible implementations, refer to the introduction of the technical effects of the fourth aspect or corresponding implementations.

[0196] In a fifteenth aspect, a communication apparatus, for example, a second terminal device as described above, is provided. The communication apparatus includes a processor and a transceiver coupled to each other, configured to implement the method described in the fifth aspect or various possible implementations. Exemplarily, the communication apparatus is a chip disposed in a communication device. Exemplarily, the communication device is a terminal device. The transceiver is implemented by, for example, an antenna, a feeder, a codec, and the like in the communication device, or if the communication apparatus is a chip disposed in the communication device, the transceiver is, for example, a communication interface in the chip connected to a radio frequency transceiving component in the communication device to implement the transceiving of information through the radio frequency transceiving component. The transceiver is configured to receive feedback information from a first terminal device. The processor is configured to obtain synchronization indication information or out-of-sync indication information of a link between the first terminal device and the second terminal device according to the received feedback information.

[0197] In a possible implementation, the processor is configured to obtain the synchronization indication information or the out-of-sync indication information of the link according to the received feedback information by:

[0198] obtaining the synchronization indication information when N1 / N is greater than a first threshold, or obtaining the out-of-sync indication information when N1 / N is less than a second threshold, where N1 represents a number of positive acknowledgments received by the second terminal device within a first time length, and N represents a total number of HARQ acknowledgment information expected to be received by the second terminal device within the first time length; or

[0199] obtaining the synchronization indication information when N2 / N is less than a third threshold, or obtaining the out-of-sync indication information when N2 / N is greater than a fourth threshold, where N2 represents a number of negative acknowledgments received by the second terminal device within the first time length, and N represents the total number of HARQ acknowledgment information expected to be received by the second terminal device within the first time length; or

[0200] obtaining the synchronization indication information when N2 / N1 is less than a fifth threshold, or obtaining the out-of-sync indication information when N2 / N is greater than a sixth threshold, where N2 represents the number of negative acknowledgments received by the second terminal device within the first time length, and N1 represents the number of positive acknowledgments received by the second terminal device within the first time length.

[0201] In a possible implementation, the processor is further configured to determine whether the link fails according to the synchronization indication information or the out-of-sync indication information.

[0202] As to the technical effects of the fifteenth aspect or various possible implementation manners, reference can be made to the introduction of the technical effects of the fifth aspect or corresponding implementation manners.

[0203] The sixteenth aspect provides a communication apparatus. The communication apparatus can be the first terminal apparatus in the method design. Illustratively, the communication apparatus is a chip arranged in a communication device. Illustratively, the communication device is a terminal device. The communication apparatus comprises a memory for storing computer executable program code, and a processor coupled with the memory. The program code stored in the memory comprises instructions, which, when executed by the processor, cause the communication apparatus to perform the method in the first aspect or any one of the possible implementation manners.

[0204] The communication apparatus can further comprise a communication interface, which can be a transceiver in the first terminal apparatus, for example, realized through an antenna, a feed line, a codec, etc. in the communication apparatus, or if the communication apparatus is a chip arranged in the first terminal apparatus, the communication interface can be an input / output interface of the chip, for example, an input / output pin, etc.

[0205] The seventeenth aspect provides a communication apparatus. The communication apparatus can be the first terminal apparatus in the method design. Illustratively, the communication apparatus is a chip arranged in a communication device. Illustratively, the communication device is a terminal device. The communication apparatus comprises a memory for storing computer executable program code, and a processor coupled with the memory. The program code stored in the memory comprises instructions, which, when executed by the processor, cause the communication apparatus to perform the method in the second aspect or any one of the possible implementation manners.

[0206] The communication apparatus can further comprise a communication interface, which can be a transceiver in the first terminal apparatus, for example, realized through an antenna, a feed line, a codec, etc. in the communication apparatus, or if the communication apparatus is a chip arranged in the first terminal apparatus, the communication interface can be an input / output interface of the chip, for example, an input / output pin, etc.

[0207] The eighteenth aspect provides a communication apparatus. The communication apparatus can be the first terminal apparatus in the method design. Illustratively, the communication apparatus is a chip arranged in a communication device. Illustratively, the communication device is a terminal device. The communication apparatus comprises a memory for storing computer executable program code, and a processor coupled with the memory. The program code stored in the memory comprises instructions, which, when executed by the processor, cause the communication apparatus to perform the method in the third aspect or any one of the possible implementation manners.

[0208] The communication device can further include a communication interface, which can be a transceiver in the first terminal device, for example, implemented through an antenna, a feed line, a codec, and the like in the communication device, or if the communication device is a chip arranged in the first terminal device, the communication interface can be an input / output interface, for example, an input / output pin, of the chip.

[0209] In a nineteenth aspect, a communication device is provided. The communication device can be the first terminal device in the method design. Illustratively, the communication device is a chip arranged in a communication apparatus. Illustratively, the communication apparatus is a terminal apparatus. The communication device includes a memory configured to store computer executable program code, and a processor coupled with the memory. The program code stored in the memory includes instructions that, when executed by the processor, cause the communication device to perform the method in the fourth aspect or any possible implementation thereof.

[0210] The communication device can further include a communication interface, which can be a transceiver in the first terminal device, for example, implemented through an antenna, a feed line, a codec, and the like in the communication device, or if the communication device is a chip arranged in the first terminal device, the communication interface can be an input / output interface, for example, an input / output pin, of the chip.

[0211] In a twentieth aspect, a communication device is provided. The communication device can be the second terminal device in the method design. Illustratively, the communication device is a chip arranged in a communication apparatus. Illustratively, the communication apparatus is a terminal apparatus. The communication device includes a memory configured to store computer executable program code, and a processor coupled with the memory. The program code stored in the memory includes instructions that, when executed by the processor, cause the communication device to perform the method in the fifth aspect or any possible implementation thereof.

[0212] The communication device can further include a communication interface, which can be a transceiver in the second terminal device, for example, implemented through an antenna, a feed line, a codec, and the like in the communication device, or if the communication device is a chip arranged in the second terminal device, the communication interface can be an input / output interface, for example, an input / output pin, of the chip.

[0213] In a twenty-first aspect, a communication system is provided, the communication system comprising the communication device of the tenth aspect, the communication device of the fifteenth aspect, or the communication device of the twentieth aspect, and comprising: the communication device of the sixth aspect, the eleventh aspect, or the sixteenth aspect, or the communication device of the seventh aspect, the twelfth aspect, or the seventeenth aspect, or the communication device of the eighth aspect, the thirteenth aspect, or the eighteenth aspect, or the communication device of the ninth aspect, the fourteenth aspect, or the nineteenth aspect.

[0214] In a twenty-second aspect, a computer storage medium is provided, the computer readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the first aspect or any possible implementation of the first aspect.

[0215] In a twenty-third aspect, a computer storage medium is provided, the computer readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the second aspect or any possible implementation of the second aspect.

[0216] In a twenty-fourth aspect, a computer storage medium is provided, the computer readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the third aspect or any possible implementation of the third aspect.

[0217] In a twenty-fifth aspect, a computer storage medium is provided, the computer readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the fourth aspect or any possible implementation of the fourth aspect.

[0218] In a twenty-sixth aspect, a computer storage medium is provided, the computer readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the fifth aspect or any possible implementation of the fifth aspect.

[0219] In a twenty-seventh aspect, a computer program product is provided, the computer program product having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the first aspect or any possible implementation of the first aspect.

[0220] In a twenty-eighth aspect, a computer program product is provided, the computer program product having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of the second aspect or any possible implementation of the second aspect.

[0221] In a twenty-ninth aspect, there is provided a computer program product comprising instructions which, when executed on a computer, cause the computer to carry out the method of the third aspect or any possible implementation thereof.

[0222] In a thirtieth aspect, there is provided a computer program product comprising instructions which, when executed on a computer, cause the computer to carry out the method of the fourth aspect or any possible implementation thereof.

[0223] In a thirty-first aspect, there is provided a computer program product comprising instructions which, when executed on a computer, cause the computer to carry out the method of the fifth aspect or any possible implementation thereof.

[0224] In the embodiments of the present application, no matter how many reference signals the first terminal device receives in a reference period, the first terminal device can obtain a first target reference signal from at least one reference signal for measurement. In this way, the problem of the uncertain number of aperiodic reference signals is solved, and the first terminal device can complete the measurement of the link according to the aperiodically transmitted reference signals. BRIEF DESCRIPTION OF DRAWINGS

[0225] Figure 1 A schematic diagram of several scenarios of V2X;

[0226] Figure 2 A schematic diagram of an application scenario of the embodiments of the present application;

[0227] Figure 3 A flowchart of the first link measurement method provided by the embodiments of the present application;

[0228] Figure 4 A schematic diagram of obtaining a first target reference signal according to the density of reference signals in the embodiments of the present application;

[0229] Figure 5 A schematic diagram of obtaining a first target reference signal according to the bandwidth of reference signals in the embodiments of the present application;

[0230] Figure 6 A schematic diagram of measuring a first link according to the first target reference signal in a first time period in the embodiments of the present application;

[0231] Figure 7 A flowchart of the second link measurement method provided by the embodiments of the present application;

[0232] Figure 8A flowchart of a first link evaluation method provided for embodiments of the application;

[0233] Figure 9 A flowchart of a second link evaluation method provided for embodiments of the application;

[0234] Figure 10 A flowchart of a third link evaluation method provided for embodiments of the application;

[0235] Figure 11 A schematic block diagram of a first terminal device provided for embodiments of the application;

[0236] Figure 12 Another schematic block diagram of a first terminal device provided for embodiments of the application;

[0237] Figure 13 A schematic block diagram of a second terminal device provided for embodiments of the application;

[0238] Figure 14 Another schematic block diagram of a second terminal device provided for embodiments of the application;

[0239] Figure 15 A schematic block diagram of a third terminal device provided for embodiments of the application;

[0240] Figure 16 Another schematic block diagram of a third terminal device provided for embodiments of the application;

[0241] Figure 17 A schematic block diagram of a fourth terminal device provided for embodiments of the application;

[0242] Figure 18 Another schematic block diagram of a fourth terminal device provided for embodiments of the application;

[0243] Figure 19 A schematic block diagram of a first terminal device provided for embodiments of the application;

[0244] Figure 20 Another schematic block diagram of a first terminal device provided for embodiments of the application;

[0245] Figure 21 A schematic block diagram of a communication device provided for embodiments of the application;

[0246] Figure 22 Another schematic block diagram of a communication device provided for embodiments of the application;

[0247] Figure 23 Yet another schematic block diagram of a communication device provided for embodiments of the application. DETAILED DESCRIPTION

[0248] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0249] In the following, some terms in the embodiments of the present application are explained and described, so as to facilitate the understanding of the skilled in the art.

[0250] 1) terminal device, including a device that provides voice and / or data connectivity to a user, specifically, including a device that provides voice to a user, or including a device that provides data connectivity to a user, or including a device that provides voice and data connectivity to a user. For example, can include a handheld device having wireless connection capability, or a processing device connected to a wireless modem. The terminal device can communicate with a core network via a radio access network (RAN), exchange voice or data with the RAN, or interact voice and data with the RAN. The terminal device can include a user equipment (UE), a wireless terminal device, a mobile terminal device, a device-to-device communication (D2D) terminal device, a vehicle to everything (V2X) terminal device, a machine-to-machine / machine-type communications (M2M / MTC) terminal device, an internet of things (IoT) terminal device, a subscriber unit, a subscriber station, a mobile station, a remote station, an access point (AP), a remote terminal, an access terminal, a user terminal, a user agent, or a user device, etc. For example, can include a mobile phone (or called "cellular" phone), a computer with a mobile terminal device, a portable, pocket, handheld, built-in computer mobile device, etc. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), etc. Also include limited devices, such as low power consumption devices, or limited storage devices, or limited computing devices, etc. For example, information sensing devices such as bar code, radio frequency identification (RFID), sensors, global positioning system (GPS), laser scanners, etc.

[0251] As an example but not limitation, in the embodiments of the present application, the terminal device can also be a wearable device. The wearable device can also be referred to as a smart wearable device or a smart wearable device, etc. It is a general term for devices that are designed and developed by applying wearable technology to daily wear, such as glasses, gloves, watches, clothing, and shoes. The wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories. The wearable device is not only a hardware device, but also a powerful function realized through software support and data interaction, cloud interaction. The broad sense of wearable smart devices includes full-featured, large-sized devices that can realize complete or partial functions without relying on smart phones, such as smart watches or smart glasses, and devices that focus on a certain application function and need to be used with other devices such as smart phones, such as various smart wristbands, smart helmets, and smart jewelry for monitoring vital signs.

[0252] And various terminal devices as introduced above, if located on a vehicle (for example, placed in or installed in the vehicle), can be considered as vehicle-mounted terminal devices, which are also referred to as on-board units (OBU). The terminal device of the embodiments of the present application can also be an on-board module, an on-board module, an on-board component, an on-board chip or an on-board unit built in a vehicle as one or more components or units. The vehicle can implement the method of the present application through the built-in on-board module, on-board module, on-board component, on-board chip or on-board unit.

[0253] In the embodiments of the present application, the terminal device can also include a relay. Or it can be understood that all devices capable of data communication with the base station can be regarded as terminal devices.

[0254] The terminal device can be a terminal device, or a module for implementing the function of the terminal device. The module can be provided in the terminal device, or can be provided independently of the terminal device. The module is, for example, a chip system, etc.

[0255] 2) Network equipment, for example, including access network (AN) equipment, such as a base station (e.g., access point), which may refer to a device in the access network that communicates with a wireless terminal device over the air interface through one or more cells, or, for example, a network device in a vehicle-to-everything (V2X) technology is a roadside unit (RSU). The base station can be used to convert received air frames to and from IP packets, acting as a router between the terminal device and the rest of the access network, where the rest of the access network may include an IP network. The RSU can be a fixed infrastructure entity that supports V2X applications and can exchange messages with other entities that support V2X applications. The network equipment can also coordinate the attribute management of the air interface. For example, the network equipment may include an evolved base station (NodeB or eNB or e-NodeB, evolutionary Node B) in a long term evolution (LTE) system or long term evolution-advanced (LTE-A), or may also include the fifth generation mobile communication technology (the 5 th The next generation node B (gNB) in the new radio (NR) system (also referred to as the NR system) of the generation, 5G) may also include a centralized unit (CU) and a distributed unit (DU) in the cloud access network (Cloud RAN) system, which is not limited in the embodiments of the present application.

[0256] Of course, network equipment can also include core network equipment, but because the technical solutions provided in the embodiments of this application mainly involve access network equipment, in the following text, unless otherwise specified, the "core network equipment" described refers to the core network equipment, and the "network equipment" or "access network equipment" described refers to the access network equipment.

[0257] 3) V2X (Vehicle-to-Everything) is the interconnection between vehicles and the outside world. It is the foundation and key technology for future smart cars, autonomous driving, and intelligent transportation systems. V2X will build on existing device-to-device (D2D) technology to optimize specific V2X application requirements. This requires further reducing V2X device access latency and resolving resource conflicts.

[0258] V2X includes several application requirements, such as direct communication between vehicles (vehicle-to-vehicle, V2V), between vehicles and roadside infrastructure (vehicle-to-infrastructure, V2I), between vehicles and pedestrians (vehicle-to-pedestrian, V2P), and between vehicles and networks (vehicle-to-network, V2N). As shown in FIG. 1. Figure 1 V2V refers to communication between vehicles; V2P refers to communication between a vehicle and a person (including a pedestrian, a cyclist, a driver, or a passenger); V2I refers to communication between a vehicle and a network device, such as an RSU; and V2N, which can be included in V2I, refers to communication between a vehicle and a base station / network.

[0259] V2P can be used to provide safety warnings to pedestrians or non-motorized vehicles on the road. Through V2I, a vehicle can communicate with the road and even other infrastructure, such as traffic lights, roadblocks, etc., to obtain road management information such as traffic light timing. V2V can be used for information exchange and reminders between vehicles, and the most typical application is for a vehicle-to-vehicle collision avoidance safety system. V2N is the most widely used form of vehicle networking, and its main function is to enable vehicles to connect to a cloud server through a mobile network and use the navigation, entertainment, or anti-theft application functions provided by the cloud server.

[0260] In V2X, the main communication is between terminal devices. For the transmission mode between terminal devices, the current standard protocol supports broadcast mode, groupcast mode, and unicast mode.

[0261] Broadcast mode: In broadcast mode, the terminal device as a sending end adopts a broadcast mode to send data, and multiple terminal devices can receive sidelink control information (SCI) or a sidelink shared channel (SSCH) from the sending end.

[0262] In sidelink, the way to ensure that all terminal devices can parse the control information from the sending end is that the sending end does not scramble the control information, or the sending end uses a scrambling code known to all terminal devices to scramble the control information.

[0263] Groupcast mode: The groupcast mode is similar to broadcast transmission, and the terminal device as a sending end adopts a broadcast mode to send data, and a group of terminal devices can parse SCI or SSCH.

[0264] Unicast mode: In the unicast mode, one terminal device sends data to another terminal device, and other terminal devices do not need or cannot analyze the data.

[0265] 4) The link measured in the embodiments of the present application (for example, the first link to be introduced later) can be a link between any two devices in a base station, a terminal device, or a road side device. For example, the link between terminal devices, the link between a base station and a terminal device, the link between a road side unit and a terminal device, the link between base stations, the link between road side units, and the like can be measured by the method provided in the embodiments of the present application.

[0266] 5) In the introduction of the embodiments of the present application, the link between terminal devices is mainly taken as an example for description. When other links need to be measured, the first terminal device and the second terminal device described in the following should be replaced by devices in the corresponding scene. For example, to measure the link between a base station and a terminal device, if downlink measurement is performed, the first terminal device can be a terminal device, and the second terminal device can be replaced by a base station; if uplink measurement is performed, the first terminal device can be replaced by a base station, and the second terminal device can be a terminal device. For another example, to measure the link between a road side unit and a terminal device, if downlink measurement is performed, the first terminal device can be a terminal, and the second terminal device can be replaced by a road side unit; if uplink measurement is performed, the first terminal device can be replaced by a road side unit, and the second terminal device can be a terminal device.

[0267] 6) The spectrum used for measuring the link can be a licensed spectrum, an unlicensed spectrum, or an unlicensed spectrum dedicated for link measurement.

[0268] 7) The aperiodic reference signal (or the reference signal transmitted aperiodically) can refer to a reference signal that does not arrive at the receiving end at a predetermined fixed time interval. Alternatively, it can refer to a reference signal that is not transmitted at a predetermined fixed time interval by the sending end, for example, a dynamically scheduled signal is generally an aperiodic signal. Alternatively, although the sending end sets the to-be-sent reference signal as a periodically transmitted signal, due to various reasons, the reference signal cannot be transmitted at a determined fixed time interval, and such a reference signal is also considered as an aperiodically transmitted reference signal. For example, when the signal is transmitted on an unlicensed spectrum, the signal is delayed due to channel sensing failure, and the signal that should be periodically transmitted is actually aperiodically transmitted. For another example, a higher priority signal is received at the time when the sending end transmits the reference signal, so that the sending end cannot transmit the reference signal, which can also cause the reference signal to be actually aperiodically transmitted.

[0269] 8) The reference signal described in the embodiments of the present application refers to a signal that can be used for link measurement. For example, the reference signal can include one or more of the following: channel state information-reference signal (CSI-RS), demodulation reference signal (DMRS), or synchornonus signal block (SSB). Alternatively, the reference signal can also include other signals that can be used for link measurement.

[0270] 9) The terms "system" and "network" in the embodiments of the present application can be used interchangeably. "At least one" refers to one or more, and "multiple" refers to two or more. "And / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the following three cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after it. "At least one of the following" or similar expressions means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can represent a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0271] In addition, unless otherwise stated, the ordinal numbers mentioned in the embodiments of the present application are used to distinguish a plurality of objects, and are not used to limit the order, time sequence, priority or importance of the plurality of objects. For example, the first filtering information and the second filtering information are only used to distinguish different filtering information, and do not necessarily mean that the contents, priority, sending order or importance of the two kinds of filtering information are different.

[0272] As introduced above, some concepts related to the embodiments of the present application are introduced, and the technical features of the embodiments of the present application are introduced below.

[0273] The so-called RLM refers to that the terminal device in the connected state can continuously track the quality of the wireless link.

[0274] For a serving cell, the base station configures a set of periodic reference signals for the terminal device to perform RLM, which can be referred to as RLM-RS. For a link between the terminal device and the base station, the base station can configure one reference signal, or in other words, one type of reference signal. Take a link as an example. The terminal device can receive the reference signal configured by the base station on the link, wherein the reference signal is periodic, and thus the terminal device can receive one (or in other words, once) reference signal in each period. When performing evaluation, the terminal device can perform out-of-sync evaluation on the link according to the reference signals received in evaluation duration 1, and can perform in-sync evaluation on the link according to the reference signals received in evaluation duration 2. The evaluation duration 1 can include one or more periods, and the evaluation duration 2 can include one or more periods. The evaluation duration 1 and the evaluation duration 2 can be equal or not equal.

[0275] For the out-of-sync evaluation process, the physical layer of the terminal device performs out-of-sync evaluation on the link according to the reference signals received in the evaluation duration 1. For example, the physical layer of the terminal device estimates the block error ratio (BLER) of the physical downlink control channel (PDCCH) according to the reference signals received in the evaluation duration 1. If the BLER estimated by the physical layer of the terminal device according to each reference signal in the evaluation duration is greater than a preset threshold q out (for example, 10%), the physical layer of the terminal device can send an out-of-sync indication to the high layer (for example, the media access control (MAC) layer) of the terminal device.

[0276] For the in-sync evaluation process, the physical layer of the terminal device performs in-sync evaluation on the link according to the reference signals received in the evaluation duration 2. For example, the physical layer of the terminal device estimates the BLER of the PDCCH according to the reference signals received in the evaluation duration 2. If the BLER estimated by the physical layer of the terminal device according to each reference signal in the evaluation duration is greater than a preset threshold q in (for example, 2%), the physical layer of the terminal device can send an in-sync indication to the high layer of the terminal device.

[0277] For a higher layer of the terminal device, if N310 link out-of-sync indications from the physical layer are continuously received, a T310 timer can be started. Before the T310 timer expires, if the higher layer can continuously receive N311 link in-sync indications from the physical layer, the higher layer considers that the terminal device and the base station have returned to a synchronization state. Alternatively, before the T310 timer expires, if the higher layer does not continuously receive N311 in-sync indications from the physical layer, it is determined that the link has failed.

[0278] In order to improve the evaluation accuracy of RLM, the standard defines two parameters as follows:

[0279] 1. Evaluation time length, or evaluation duration.

[0280] The terminal device filters (such as linear average) the reference signals received within the evaluation duration, and then evaluates the BLER of the PDCCH according to the filtered reference signals. The relevant evaluation duration includes an out-of-sync evaluation duration and an in-sync evaluation duration. The out-of-sync evaluation duration can be represented as T Evaluate_out , for example, the typical value is 200 ms, and the in-sync evaluation duration can be represented as T Evaluate_in , for example, the typical value is 100 ms.

[0281] Taking the reference signal as a channel state information-reference signal (CSI-RS) for example, the in-sync evaluation duration and the out-of-sync evaluation duration can refer to Table 1.

[0282] Table 1

[0283]

[0284]

[0285] The embodiments of the present application do not involve DRX related issues, so only the non-DRX case is discussed.

[0286] In Table 1, ceil() represents the upward rounding operation, M out represents the number of reference signals participating in evaluation within one evaluation duration when performing out-of-sync evaluation, for example, M out has a value of 20. M in represents the number of reference signals participating in evaluation within one evaluation duration when performing in-sync evaluation, for example, M in has a value of 10. T CSI-RS represents the period of the reference signal CSI-RS. P is a correction value, which is a time compensation for not being able to measure all reference signals due to some reasons, for example, when all reference signals can participate in evaluation, P = 1.

[0287] In the RLM procedure, the physical layer of the terminal device can perform out-of-sync evaluation. For example, the physical layer of the terminal device combines the reference signals received in each period within T Evaluate_out . Then, the physical layer of the terminal device compares the combined result with q out . If the combined result is greater than q out , the physical layer of the terminal device sends a link out-of-sync indication to the upper layer of the terminal device.

[0288] In addition, the physical layer of the terminal device can also perform in-sync evaluation. For example, the physical layer of the terminal device combines the reference signals received in each period within T Evaluate_in . Then, the physical layer of the terminal device compares the combined result with q in . If the combined result is greater than q in , the physical layer of the terminal device sends a link in-sync indication to the upper layer of the terminal device.

[0289] V2X is the interconnection between vehicles and the outside world, which is the basis and key technology for future intelligent vehicles, autonomous driving, and intelligent transportation systems. Therefore, currently, it is proposed to perform RLM on the sidelink of V2X, so as to ensure that data transmission can be performed on a high-quality sidelink. For V2X, currently, it is proposed not to use periodic reference signals, but to use aperiodic reference signals for evaluation. According to the foregoing introduction, it can be known that the RLM of the Uu interface currently uses periodic signals, and the terminal device can receive a reference signal once (or one) in each period, and the terminal device can evaluate according to the reference signal. However, if it is an aperiodic reference signal, the number of reference signals received by the terminal device in a certain period of time can be uncertain, which can be more or less. Therefore, how the terminal device should evaluate is still inconclusive.

[0290] In view of this, the technical solutions of the embodiments of the present application are provided. In the embodiments of the present application, the first terminal device receives at least one reference signal in a first reference period, and the first terminal device obtains a first target reference signal according to the at least one reference signal. If there is at least one reference period, the first terminal device can obtain the first target reference signal for each reference period, so that the first terminal device can perform synchronization evaluation on the first link according to the at least one first target reference signal to obtain synchronization indication information, or perform out-of-sync evaluation to obtain out-of-sync indication information. That is, no matter how many reference signals the first terminal device receives in a reference period, the first terminal device can perform evaluation according to the at least one reference signal to obtain the first target reference signal. In this way, the problem of uncertain number of aperiodic reference signals is solved, so that the first terminal device can complete the evaluation of the link according to the aperiodic reference signals.

[0291] The technical solutions provided by the embodiments of the present application can be applied to a D2D scenario, which can be an NR D2D scenario or an LTE D2D scenario, or can be applied to a V2X scenario, which can be an NR V2X scenario or an LTE V2X scenario, or can be applied to other scenarios or other communication systems, for example, can also be used for link evaluation of a Uu interface of an LTE system or an NR system. The carrier frequency of the related sidelink bearer can be a licensed spectrum, an unlicensed spectrum, or a shared spectrum, and the specific implementation is not limited.

[0292] The network architecture to which the embodiments of the present application are applied will be introduced below. Please refer to Figure 2 , which is a network architecture to which the embodiments of the present application are applied.

[0293] Figure 2 The network device and two terminal devices, terminal device 1 and terminal device 2, are included in the network architecture. Both of the two terminal devices can be connected with the network device, or only the terminal device 1 can be connected with the network device, and the terminal device 2 can not be connected with the network device. The two terminal devices can also communicate with each other through a sidelink, that is, the terminal device 1 is a terminal device with network coverage, and the terminal device 2 is a terminal device with partial network coverage. Figure 2 For example, only the terminal device 1 is connected with the network device. Of course Figure 2 The number of terminal devices in the network architecture is only an example. In actual application, the network device can serve multiple terminal devices.

[0294] Figure 2 The network device in the network architecture is, for example, an access network device, such as a base station. In different systems, the access network device corresponds to different devices, for example, in the fourth generation mobile communication technology (the 4 thIn a 4G (4th generation) system, it may correspond to an eNB, and in a 5G system, it may correspond to an access network device in 5G, such as a gNB, or may be an access network device in a subsequently evolved communication system.

[0295] in, Figure 2 The terminal device in the example is a vehicle-mounted terminal device or a vehicle, but the terminal device in the embodiments of the present application is not limited thereto.

[0296] Next, the technical solutions provided by the embodiments of the present application are described in conjunction with the accompanying drawings. In each embodiment of the present application, the link quality evaluation (estimate), link quality measurement (measurement), and link quality monitoring (monitoring) described are equivalent. That is, the concepts of "evaluation", "measurement", and "monitoring" described in the various embodiments of the present application are interchangeable.

[0297] This application embodiment provides a link measurement method, see Figure 3 , which is the flow chart of this method. In the following introduction, this method is applied to Figure 3 Take the network architecture shown as an example. In addition, the method can be performed by two communication devices, such as a first communication device and a second communication device. Among them, the first communication device or the second communication device can be a network device or a communication device that can support the network device to implement the functions required by the method, or can be a terminal device or a communication device that can support the terminal device to implement the functions required by the method, and of course can also be other communication devices, such as a chip system. There is no restriction on the implementation method of the first communication device or the second communication device. For example, the two communication devices can be implemented in the same form, such as both are implemented in the form of devices, or the two communication devices can also be implemented in different forms, such as the first communication device is implemented in the form of a device, and the second communication device is implemented in the form of a chip system, and so on. Among them, the network device is, for example, a base station.

[0298] For ease of description, the following takes the method executed by a terminal device and a terminal device as an example, that is, the first communication device is a terminal device (for example, referred to as the first terminal device) and the second communication device is also a terminal device (for example, referred to as the second terminal device). Figure 2 As an example, the network architecture shown in FIG. 1 is used. Therefore, the first terminal device described below can implement Figure 2 The functions of the terminal device 1 in the network architecture shown in the figure can be realized by the second terminal device described below. Figure 2 Functionality of a terminal 2 in the network architecture shown.

[0299] S31. The first terminal device configures a reference period.

[0300] In the embodiments of the present application, the first terminal device can first configure the link evaluation parameter. For example, the link evaluation parameter includes a reference period. In the embodiments of the present application, the reference signal is transmitted aperiodically, but the reference period can still be set. The reference period can be understood as a time length, and the first terminal device expects to receive one or more reference signals, so that the existing RLM process and framework can be compatible, and the design process is simplified. In the sidelink, the transmission time of the reference signal is irregular, that is, the reference signal cannot be guaranteed to be transmitted periodically, and the number of reference signals received by the first terminal device can be different, for example, one or more reference signals can be received, or 0 reference signals (or no reference signals) can be received, so the number of reference signals that can be received in a reference period cannot be guaranteed.

[0301] For example, the first terminal device can determine the time length of the reference period by itself, that is, the time length of the reference period can be configured by the first terminal device, or the time length of the reference period can be specified by a protocol, and the first terminal device can directly configure according to the protocol. Alternatively, the time length of the reference period can be configured by the second terminal device, and the second terminal device can send first indication information to the first terminal device after configuring the time length of the reference period, and the first indication information is used to indicate the time length of the reference period. After receiving the first indication information, the first terminal device can configure the time length of the reference period. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the time length of the reference period can also be configured by a network device (such as a base station), and the network device can send first indication information to the first terminal device after configuring the time length of the reference period, and the first indication information is used to indicate the time length of the reference period. After receiving the first indication information, the first terminal device can configure the time length of the reference period.

[0302] Regardless of which device determines the time length of the reference period, one determination method is that the parameters of the first service do not need to be considered when determining the time length of the reference period. Here, the first service is the service transmitted on the first link, and the first link is the link between the first terminal device and the second terminal device. The first terminal device receives at least one reference signal on the first link, and the first terminal device to be measured is also the first link. In this way of determining the time length of the reference period, for example, the determined time length of the reference period is 40 ms, or it can also be other lengths, and the time length of the reference period can be determined according to the time length of the expected received reference signal.

[0303] Alternatively, since the transmission of the reference signal is related to the service, in general, the reference signal is transmitted together with the service, for example, the demodulation signal (DMRS) of the control channel PSCCH of the service as the reference signal, or the demodulation signal (DMRS) of the data channel PSSCH of the service as the demodulation signal, or other reference signals transmitted together with the PSSCH in a time slot. Therefore, another way to determine the length of the reference period is that the parameters of the first service can be considered when determining the length of the reference period. By determining the length of the reference period in combination with the parameters of the service, the link evaluation parameters are associated with the service, which can make the measurement result more matched to the requirements of the service and more accurate.

[0304] The parameters of the first service include, for example, the expected period length of the data packet of the first service, or the retransmission configuration information of the first service, or the expected period length of the data packet of the first service and the retransmission configuration information of the data packet of the first service. Wherein, if there is only one service transmission on the first link, the service is the first service, the expected period of the data packet of the service is the expected period length of the data packet of the first service, and the retransmission configuration information of the data packet of the service is the retransmission configuration information of the first service. Alternatively, if there are multiple service transmissions on the first link, the service with the minimum expected period length of the data packet can be determined from them, and the service is taken as the first service, the expected period length of the data packet of the service is the expected period length of the data packet of the first service, and the retransmission configuration information of the data packet of the service is the retransmission configuration information of the first service.

[0305] In this way of determining the length of the reference period, for example, the parameters of the first service include the expected period length of the data packet of the first service and the retransmission configuration information of the data packet of the first service, the reference period can satisfy the following formula 1:

[0306] T = min (first threshold, ceil (T packet × P1) (formula 1)

[0307] In formula 1, ceil() represents rounding up. Alternatively, formula 1 can also be T = min (first threshold, ), Downward rounding. T represents the reference period, T packetP1 represents the expected cycle length of the data packet of the first service, and P1 represents the retransmission configuration information of the first service. By setting the first threshold, the test frequency of the terminal device can be kept moderate, which can meet the test requirements and ensure that the power consumption of the terminal device is at a certain level, so as to prevent excessive power consumption. The first threshold can be configured by signaling, for example, configured by the network device through the first indication information, or configured by the second terminal device through the first indication information, or the first threshold can also be set by the first terminal device itself, or can be specified by the protocol, for example, the protocol specifies that the first threshold is 2ms.

[0308] The value of P1 is related to the retransmission configuration of the first service, for example, related to the hybrid automatic repeat request (HARQ) retransmission of the first service. The retransmission configuration information of the data packet of the first service can indicate the retransmission mode of the data packet of the first service. For example, the retransmission configuration information can include one of no HARQ retransmission of the first service, blind retransmission of the first service, or adaptive retransmission of the first service. For example, if the first service does not perform HARQ retransmission, that is, the first service only performs single transmission, then P1=k (k is a variable or constant that can be set, such as k=1 or k=2); or if the first service performs blind retransmission, then P1=k / N1, N1 represents the number of times that one data packet included in the first service is blindly retransmitted, wherein the number of times that different data packets included in the first service are blindly retransmitted can be the same or different; or if the first service performs adaptive retransmission, P1=k / N2, N2 represents the expected number of times that one data packet included in the first service is adaptively retransmitted by HARQ, for example, N2=1.2, or other values. Or if the first service does not perform HARQ retransmission, that is, the first service only performs single transmission, then P1=1, or if the first service performs blind retransmission, then P1=1 / N1, etc. k is a constant, such as k being equal to 1 or 2, or k can be a variable.

[0309] The number of times that different data packets included in the first service are adaptively retransmitted by HARQ can be the same or different. The way of determining the value of P1 here is only an example, and the specific is not limited thereto.

[0310] The blind retransmission means that the sending end of the first service will retransmit the first service after sending the first service, regardless of whether the feedback information from the receiving end is received, which is equivalent to sending the first service multiple times to improve coverage. The adaptive retransmission means that the sending end of the first service will determine whether to retransmit according to the feedback information from the receiving end after sending the first service.

[0311] Of course, the parameters of the first service can also include other parameters, and the formula satisfied by the reference period can be correspondingly different, and the specific implementation is not limited.

[0312] S32, in the first reference period, the second terminal device sends at least one reference signal to the first terminal device, and the first terminal device receives at least one reference signal from the second terminal device. The at least one reference signal is non-periodic transmission, or in other words, the at least one reference signal is irregular.

[0313] The "irregular" in various embodiments of the application refers to that the reference signal is randomly arrived, rather than sent according to a certain period.

[0314] For example, the reference signal is a demodulation reference signal (DMRS) of a control channel or a data channel, and the sending of the reference signal is based on scheduling.

[0315] For another example, the reference signal is a reference signal specially used for RLM, and the reference signal is sent along with a service data channel (such as PSSCH), then the reference signal is also based on scheduling.

[0316] The at least one reference signal, for example, includes one, two or more reference signals. The at least one reference signal is used for wireless link measurement. It should be noted that in addition to the wireless link measurement, the first terminal device can also perform other measurement processes, and other measurement processes can use other reference signals. In addition to receiving the at least one reference signal, the first terminal device can also receive reference signals for completing other functions, or can not receive reference signals for completing other functions. These reference signals are not within the scope of consideration of the embodiments of the application. The reference signals mentioned in the embodiments of the application are reference signals for completing wireless link measurement.

[0317] After determining the reference period, the first terminal device can receive the reference signal from the second terminal device in the time length of the reference period as a time unit. In the embodiments of the application, the first terminal device can receive one reference signal in a reference period, or can receive at least two reference signals, or can not receive a reference signal (here, the reference signal not received refers to the reference signal for RLM, and whether the first terminal device can receive the reference signal for completing other measurement processes is not limited in the embodiments of the application). Figure 3 Take the first terminal device receiving at least one reference signal in the first reference period as an example.

[0318] S33, the first terminal device determines a first target reference signal in the first reference period according to the at least one reference signal.

[0319] If the first terminal device only receives one reference signal in the first reference period, the first terminal device can directly take the reference signal as the first target reference signal, so that the first target reference signal can be involved in subsequent evaluation. Alternatively, if the first terminal device receives at least two reference signals in the first reference period, the first terminal device can obtain a reference signal from the at least two reference signals, i.e., the first target reference signal, so that the first target reference signal can be involved in subsequent measurement.

[0320] There can be different ways for the first terminal device to determine the first target reference signal, which will be introduced below as examples.

[0321] As a first possible way for the first terminal device to determine the first target reference signal, the first terminal device can determine one of the at least one reference signal as the first target reference signal.

[0322] For example, the first terminal device can take the first received reference signal in the at least one reference signal as the first target reference signal; or the first terminal device can take the last received reference signal in the at least one reference signal as the first target reference signal; or the first terminal device can also take the reference signal in the middle of the at least one reference signal as the first target reference signal, for example, the number of the at least one reference signal is 3, i.e., the first terminal device receives 3 reference signals in the reference period, then the first terminal device can take the second received reference signal as the first target reference signal, or for example, the number of the at least two reference signals is 4, i.e., the first terminal device receives 4 reference signals in the reference period, then the first terminal device can take the second received reference signal or the third received reference signal as the first target reference signal. In fact, the first terminal device can take any one of the at least one reference signal as the first target reference signal, and the specific selection of which reference signal as the first target reference signal is not limited by the embodiments of the present application.

[0323] As a second possible way for the first terminal device to determine the first target reference signal, the first terminal device can combine part of the at least two reference signals or all of the at least two reference signals, and take the combined signal as the first target reference signal. In the embodiments of the present application, the plurality of signals are combined, and one combination manner is, for example, linear averaging of the plurality of signals, or there can be other combination manners, which are not limited in detail.

[0324] For example, the first terminal device can combine all of the at least one reference signal to obtain the first target reference signal; or the first terminal device can combine part of the at least one reference signal to obtain the first target reference signal, for example, combine the first received reference signal and the last received reference signal in the at least one reference signal to obtain the first target reference signal, or randomly select part of the at least one reference signal to obtain the first target reference signal. If the first terminal device combines part of the at least one reference signal to obtain the first target reference signal, the embodiments of the present application do not limit which reference signals in the at least one reference signal are combined by the first terminal device.

[0325] As described above, the first terminal device obtains the first target reference signal by taking the first reference period as an example. For other reference periods, the first terminal device obtains the first target reference signal in a similar manner.

[0326] By setting the reference period and obtaining the first target reference signal according to the at least one reference signal received in the reference period, the problem that the non-periodic transmission reference signal cannot be measured due to uneven arrival quantity is solved, and the compatibility of the existing RLM process is good.

[0327] As a third possible way for the first terminal device to determine the first target reference signal, the first terminal device can determine the first target reference signal according to a link evaluation parameter. As described above, the link evaluation parameter includes the reference period, and in addition, the link evaluation parameter can also include the reference density or the reference bandwidth, or include the reference density and the reference bandwidth. Here, the link evaluation parameter used by the first terminal device to determine the first target reference signal can be the reference density or the reference bandwidth. The density of the reference signal refers to the number of frequency domain units carrying the reference signal in the bandwidth occupied by one reference signal, and the cumulative density of the reference signal is the sum of the densities of one or more reference signals. The frequency domain unit is, for example, a resource block (resource block, RB), or a resource element (resource element, RE), or other frequency domain units.

[0328] The first terminal device determines the first target reference signal according to the reference density. In this way, when the cumulative density of the first N reference signals in the at least one reference signal is greater than or equal to the reference density, the first terminal device takes the first N reference signals as the first target reference signal, N being an integer greater than or equal to 1. For example, in the first reference period, the first terminal device continuously receives the reference signals, for example, after receiving each reference signal, the first terminal device can determine whether the cumulative density of all the reference signals received in the first reference period is greater than or equal to the reference density. If the cumulative density of all the reference signals received in the first reference period is less than the reference density, the first terminal device can continue to receive the reference signals, and make a judgment after receiving the next reference signal; or if the cumulative density of all the reference signals received in the first reference period is greater than or equal to the reference density, the first terminal device takes all the reference signals received in the first reference period as the first target reference signal. For example, at this time, the number of all the reference signals received in the first reference period is N, if N = 1, the first terminal device can take the first reference signal as the first target reference signal, or if N > 1, the first terminal device can combine all the reference signals received in the first reference period to obtain the first target reference signal.

[0329] For example, the reference density is 3, and in the first reference period, the density of the reference signals received by the first terminal device can refer to Figure 4 . Among them, Figure 4 The dashed box in the figure indicates a reference signal. As Figure 4As shown, at time t0, the first terminal device receives 1 reference signal with density 1 in the first reference period, the first terminal device can determine whether the cumulative density of all the reference signals received in the reference period is greater than or equal to the reference density, since the reference density is 3, and the cumulative density of the reference signals is 1 at this time, therefore the cumulative density of all the reference signals received in the reference period is less than the reference density, then the first terminal device can continue to receive the reference signals. At time t1, the first terminal device receives 1 reference signal with density 1, the first terminal device can determine whether the cumulative density of all the reference signals received in the first reference period is greater than or equal to the reference density, since the reference density is 3, and the cumulative density of the reference signals is 2 at this time, therefore the cumulative density of all the reference signals received in the reference period is less than the reference density, then the first terminal device can continue to receive the reference signals. At time t2, the first terminal device receives 1 reference signal with density 1, the first terminal device can determine whether the cumulative density of all the reference signals received in the first reference period is greater than or equal to the reference density, since the reference density is 3, and the cumulative density of the reference signals is 2 at this time, therefore the cumulative density of all the reference signals received in the first reference period is equal to the reference density, which means that the first terminal device has received a reference signal with density 3 in the first reference period, and the measurement accuracy can be reached, therefore the first terminal device can take the three reference signals as the first target reference signal, for example, the first terminal device can combine the three reference signals to obtain the first target reference signal, and the first target reference signal can participate in the measurement of the first link. And in the first reference period, if the terminal device still receives the reference signal, then the subsequent received reference signal can not need to participate in the measurement of the first link.

[0330] The first terminal device determines the first target reference signal according to the reference bandwidth. In this way, in the case that the bandwidth of the first N reference signals accumulated in the at least one reference signal is greater than or equal to the reference bandwidth, the first terminal device takes the first N reference signals as the first target reference signal, N being an integer greater than or equal to 1. For example, in the first reference period, the first terminal device continuously receives the reference signals, for example, every time a reference signal is received, the first terminal device can determine whether the accumulated bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth. If the accumulated density of all the reference signals received in the first reference period is less than the reference bandwidth, the first terminal device can continue to receive the reference signals, and make a judgment again after receiving the next reference signal; or if the accumulated bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth, the first terminal device takes all the reference signals received in the first reference period as the first target reference signal. For example, if the number of all the reference signals received in the first reference period is N, if N = 1, the first terminal device can take the reference signal as the first target reference signal, or if N > 1, the first terminal device can combine all the reference signals received in the first reference period to obtain the first target reference signal.

[0331] For example, the reference bandwidth is 48 RBs, and in the first reference period, the bandwidth of the reference signals received by the first terminal device can refer to Figure 5 . Among them, Figure 5 The dashed box in the figure indicates a reference signal. As Figure 5As shown, in the first reference period, the first terminal device receives 1 reference signal with a bandwidth of 16 RBs at time t0, the first terminal device can determine whether the cumulative bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth, because the reference bandwidth is 48 RBs, at this time the cumulative bandwidth of the reference signals is 16 RBs, therefore the cumulative bandwidth of all the reference signals received in the first reference period is less than the reference bandwidth, then the first terminal device can continue to receive the reference signals. At time t1, the first terminal device receives 1 reference signal with a bandwidth of 12 RBs, the first terminal device can determine whether the cumulative bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth, because the reference bandwidth is 48 RBs, at this time the cumulative bandwidth of the reference signals is 28 RBs, therefore the cumulative bandwidth of all the reference signals received in the first reference period is less than the reference bandwidth, then the first terminal device can continue to receive the reference signals. At time t1, the first terminal device receives 1 reference signal with a bandwidth of 12 RBs, the first terminal device can determine whether the cumulative bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth, because the reference bandwidth is 48 RBs, at this time the cumulative bandwidth of the reference signals is 48 RBs, therefore the cumulative bandwidth of all the reference signals received in the first reference period is less than the reference bandwidth, then the first terminal device can continue to receive the reference signals. At time t3, the first terminal device receives 1 reference signal with a bandwidth of 8 RBs, the first terminal device can determine whether the cumulative bandwidth of all the reference signals received in the first reference period is greater than or equal to the reference bandwidth, because the reference bandwidth is 48 RBs, at this time the cumulative bandwidth of the reference signals is 48 RBs, therefore the cumulative bandwidth of all the reference signals received in the first reference period is equal to the reference bandwidth, which means that the first terminal device has received the reference signal with a bandwidth of 48 RBs in the first reference period, and the measurement accuracy can be reached, therefore the first terminal device can take the 4 reference signals as the first target reference signal, for example, the first terminal device can combine the 4 reference signals to obtain the first target reference signal, and the first target reference signal can participate in the measurement of the first link. In the first reference period, if the terminal device still receives the reference signal, then the subsequent received reference signal can not need to participate in the measurement of the first link.

[0332] As to the reference density, for example, the first terminal device can determine the reference density by itself, that is, the reference density can be configured by the first terminal device, or the reference density can be specified by a protocol. Alternatively, the reference density can be configured by the second terminal device, and after the second terminal device configures the reference density, the second terminal device can send third indication information to the first terminal device, where the third indication information is used to indicate the reference density. After the first terminal device receives the third indication information, the first terminal device can determine the reference density. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the reference density can also be configured by a network device (for example, a base station), and after the network device configures the reference density, the network device can send third indication information to the first terminal device, where the third indication information is used to indicate the reference density. After the first terminal device receives the third indication information, the first terminal device can determine the reference density. The third indication information and the first indication information can be the same indication information, or can be different indication information.

[0333] As to the reference bandwidth, for example, the first terminal device can determine the reference bandwidth by itself, that is, the reference bandwidth can be configured by the first terminal device, or the reference bandwidth can be specified by a protocol. Alternatively, the reference bandwidth can be configured by the second terminal device, and after the second terminal device configures the reference bandwidth, the second terminal device can send fourth indication information to the first terminal device, where the fourth indication information is used to indicate the reference bandwidth. After the first terminal device receives the fourth indication information, the first terminal device can determine the reference bandwidth. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the reference bandwidth can also be configured by a network device (for example, a base station), and after the network device configures the reference bandwidth, the network device can send fourth indication information to the first terminal device, where the fourth indication information is used to indicate the reference bandwidth. After the first terminal device receives the fourth indication information, the first terminal device can determine the reference bandwidth. The fourth indication information and the first indication information can be the same indication information, or can be different indication information. The fourth indication information and the third indication information can be the same indication information, or can be different indication information.

[0334] By configuring the link evaluation parameters such as the length of the reference period, the reference density, or the reference bandwidth, the accumulation of signals can be performed according to the reference density or the reference bandwidth within the reference period, so as to solve the problem that the density or the bandwidth of the received reference signal does not meet the measurement accuracy, to try to ensure the measurement accuracy, and to reduce the complexity of the design of the device and the system.

[0335] As introduced above, the first terminal device can determine the first target reference signal in several ways. Alternatively, the first terminal device can determine the first target reference signal in other ways. As to which way the first terminal device determines the first target reference signal, the first terminal device can determine by itself, or the second terminal device can configure, or if the second terminal device is also a terminal device, the network device can configure, or the protocol can specify.

[0336] The process of S33 can be completed by the physical layer of the first terminal device.

[0337] S34, the first terminal device obtains synchronization indication information or out-of-sync indication information of the first link according to at least one target reference signal in at least one reference period, the first link is a link between the first terminal device and the second terminal device, the at least one reference period includes the first reference period, and the at least one target reference signal includes the first target reference signal.

[0338] As introduced above, the first terminal device can determine the first target reference signal in several ways. Alternatively, the first terminal device can determine the first target reference signal in other ways. As to which way the first terminal device determines the first target reference signal, the first terminal device can determine by itself, or the second terminal device can configure, or if the second terminal device is also a terminal device, the network device can configure, or the protocol can specify.

[0339] Thus, the first terminal device can perform synchronization measurement on the first link according to at least one target reference signal in at least one reference period to obtain synchronization indication information, or the first terminal device can perform out-of-sync measurement on the first link according to at least one target reference signal in at least one reference period to obtain out-of-sync indication information.

[0340] The first terminal device can measure the link in time units of the evaluation duration included in the link evaluation parameters, i.e., the first terminal device can measure the link according to the reference signals received in the evaluation duration. The evaluation duration can also be referred to as a measurement duration or a monitoring duration, etc. For example, the evaluation duration in which the first terminal device performs the evaluation is referred to as a first duration, and the first duration includes one or more reference periods, and the one or more reference periods include the at least one reference period. The first terminal device measures at least one target reference signal in the at least one reference period, i.e., measures at least one target reference signal in the first duration. The first duration can refer to a synchronization evaluation duration for performing synchronization measurement, or refer to an out-of-sync evaluation duration for performing out-of-sync measurement. The synchronization evaluation duration and the out-of-sync evaluation duration can have the same length or different lengths. In addition, the number of reference periods included in the evaluation duration is greater than or equal to the number of the at least one reference period. The at least one reference period refers to a reference period in which the reference signal is received, i.e., in the reference periods included in the evaluation duration, the first terminal device can not receive the reference signal in some reference periods, and these reference periods are not included in the at least one reference period. The at least one reference period can be continuous in time or discontinuous in time.

[0341] For example, the evaluation duration includes 5 reference periods, which are reference period 1, reference period 2, reference period 3, reference period 4, and reference period 5. The first terminal device receives the reference signal in reference period 1, reference period 2, reference period 3, and reference period 4, and can obtain target reference signal 1 according to the reference signal received in reference period 1, target reference signal 2 according to the reference signal received in reference period 2, target reference signal 3 according to the reference signal received in reference period 3, and target reference signal 4 according to the reference signal received in reference period 4. The first terminal device does not receive the reference signal in reference period 5, and cannot obtain the target reference signal. Therefore, reference period 1, reference period 2, reference period 3, and reference period 4 can participate in measurement, and reference period 5 does not participate in measurement. The at least one reference period includes reference period 1, reference period 2, reference period 3, and reference period 4, and does not include reference period 5. It can be seen that the at least one reference period is continuous in time in this case.

[0342] For another example, if the evaluation duration includes 5 reference periods, i.e., reference period 1, reference period 2, reference period 3, reference period 4 and reference period 5, and the first terminal device receives the reference signal in reference period 1, reference period 2 and reference period 4, the first terminal device can obtain the target reference signal 1 according to the reference signal received in reference period 1, the target reference signal 2 according to the reference signal received in reference period 2, and the target reference signal 3 according to the reference signal received in reference period 4, and the first terminal device does not receive the reference signal in reference period 3 and reference period 5, and cannot obtain the target reference signal, then reference period 1, reference period 2 and reference period 4 can participate in the measurement, and reference period 3 and reference period 5 do not participate in the measurement. Then, the at least one reference period includes reference period 1, reference period 2 and reference period 4, and does not include reference period 3 and reference period 5. It can be seen that in this case, the at least one reference period is discontinuous in time.

[0343] Alternatively, the first terminal device can also not evaluate the first link in the evaluation duration when measuring the first link, that is, the evaluation duration can not be set, and the first terminal device measures the first link in at least one reference period. The at least one reference period refers to a reference period in which the reference signal is received. For example, it is stipulated that the first terminal device measures the first link after receiving the reference signal in P reference periods, and P is an integer greater than or equal to 1. If P is greater than 1, the P reference periods can be continuous or discontinuous. The difference between setting the evaluation duration is that the evaluation duration limits the total number of reference periods, but does not limit the number of reference periods in which the reference signal is actually received. The method of not setting the evaluation duration limits the number of reference periods in which the reference signal is actually received.

[0344] For example, the first duration can be determined by the first terminal device, that is, the first duration can be configured by the first terminal device, or the first duration can be specified by a protocol. Alternatively, the first duration can be configured by the second terminal device, and the second terminal device can send second indication information to the first terminal device after configuring the first duration, and the second indication information is used to indicate the first duration. After receiving the second indication information, the first terminal device can determine the first duration. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the first duration can also be configured by a network device (such as a base station), and the network device can send second indication information to the first terminal device after configuring the first duration, and the second indication information is used to indicate the first duration. After receiving the first indication information, the first terminal device can determine the first duration. The fourth indication information and the first indication information can be the same indication information, or can be different indication information.

[0345] Alternatively, the first terminal device can determine the value of P by itself, that is, the value of P can be configured by the first terminal device, or the value of P can be specified by a protocol. Alternatively, the value of P can be configured by the second terminal device, and the second terminal device can send second indication information to the first terminal device after configuring the value of P, and the second indication information is used to indicate the value of P. After receiving the second indication information, the first terminal device can determine the value of P. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the value of P can also be configured by a network device (such as a base station), and the network device can send second indication information to the first terminal device after configuring the value of P, and the second indication information is used to indicate the value of P. After receiving the first indication information, the first terminal device can determine the value of P. The fourth indication information and the first indication information can be the same indication information, or can be different indication information.

[0346] The second indication information and the first indication information can be the same indication information, or can be different indication information. The second indication information and the third indication information can be the same indication information, or can be different indication information. The second indication information and the fourth indication information can be the same indication information, or can be different indication information. For example, the first indication information, the second indication information, the third indication information and the fourth indication information can be the same indication information, which means that the reference period, the first time length, the reference density and the reference bandwidth can be configured at the same time through one indication information, without too much indication information, which helps to save signaling overhead. Alternatively, the first indication information, the second indication information, the third indication information and the fourth indication information can be different indication information respectively, which means that different link evaluation parameters are configured through different indication information respectively, so that the configuration is more targeted. Alternatively, some of the first indication information, the second indication information, the third indication information and the fourth indication information can be the same indication information, for example, the first indication information and the second indication information are the same indication information, the third indication information and the fourth indication information are the same indication information, and the like, without limitation.

[0347] If the first time length is determined by the first terminal device itself, for example, the first terminal device can determine the first time length according to the reference period.

[0348] For example, the first time length is an evaluation time length for performing synchronization measurement, that is, the first terminal device is to obtain synchronization indication information of the first link according to the first target reference signal in at least one period included in the first time length, and the first time length can satisfy the following formula 2:

[0349] L in= max(100 ms, M in x T) (Equation 2)

[0350] In Equation 2, L in denotes the first duration, T denotes the duration of the reference period, and M in denotes the number of reference signals participating in the synchronization measurement within one first duration when the first link is measured for synchronization according to the periodic reference signals, for example, M in = 10. The unit of the first duration is, for example, millisecond.

[0351] For example, the first duration is the evaluation duration for performing the synchronization measurement, that is, the first terminal device is to obtain the synchronization indication information of the first link according to the first target reference signal in at least one period included in the first duration, the first duration can satisfy Equation 3 as follows:

[0352] L out = max(200 ms, M out x T) (Equation 3)

[0353] In Equation 3, L out denotes the first duration, T denotes the duration of the reference period, and M out denotes the number of reference signals participating in the synchronization measurement within one first duration when the first link is measured for synchronization according to the periodic reference signals, for example, M out = 20. The unit of the first duration is, for example, millisecond.

[0354] The above equations are only examples, and if the first terminal device determines the first duration according to the reference period, the determination manner is not limited to the above equations.

[0355] In addition, Equation 2 or Equation 3 above only considers the reference period, or in addition to the reference period, other link evaluation parameters can also be considered when determining the first duration. For example, the first terminal device determines the first duration according to the reference period, and the first terminal device can also determine the first duration according to the reference period and a first parameter. The first parameter includes, for example, a parameter related to the reference density, or a parameter related to the reference bandwidth, or a parameter related to the reference density and a parameter related to the reference bandwidth.

[0356] For example, the first terminal device determines the first duration according to the reference period and the parameter related to the reference density.

[0357] For example, the first duration is the evaluation duration for performing the synchronization measurement, that is, the first terminal device is to obtain the synchronization indication information of the first link according to the first target reference signal in at least one period included in the first duration, the first duration can satisfy Equation 4 as follows:

[0358] L in = max (second threshold, ceil (M in × P2) × T) (Formula 4)

[0359] In Formula 4, ceil() represents rounding up. Alternatively, Formula 4 can also be L in = max (second threshold, represents rounding down. L in represents the first time length, T represents the time length of the reference period, M in represents the number of reference signals participating in the synchronization measurement in one first time length when the first link is measured for synchronization according to the periodic reference signal, for example, M in = 10. The unit of the first time length is, for example, milliseconds. By setting the second threshold, the effectiveness of the test of the first terminal device can be maintained, that is, enough samples can be counted and the samples are associated. For example, the second threshold can be related to the speed of the first terminal device. The second threshold can be configured by signaling, for example, configured by the network device through the second indication information, or configured by the second terminal device through the second indication information, or the second threshold can also be set by the first terminal device itself, or can be specified by the protocol. For example, when the speed of the first terminal device is high (for example, the speed range corresponding to high speed is (120, 250] kilometers / hour), the second threshold = 80 ms, and when the speed of the first terminal device is low (for example, the speed range corresponding to low speed is [0, 120] kilometers / hour), the second threshold = 140 ms.

[0360] P2 represents a parameter related to the reference density. For example, if the reference density is less than or equal to the actual received reference signal density in one reference period, P2 = 1. Alternatively, P2 can also be a density ratio, P2 is the ratio of the actual received reference signal density in one reference period to the reference density, that is, P2 = actual received reference signal density in one reference period / reference density. For example, the actual received reference signal density in one reference period is 1, and the reference density is 3, then P2 = 3, that is, P2 = reference density / actual signal density. Alternatively, P2 can also be other forms of values, as long as P2 is related to the reference density, and the lower the actual signal density, the more measurement samples are needed.

[0361] For example, the first time length is the evaluation time length for performing out-of-sync measurement, that is, the first terminal device is to obtain the out-of-sync indication information of the first link according to the first target reference signal in at least one period included in the first time length, then the first time length can satisfy the following Formula 5:

[0362] Lout = max (second threshold, ceil (M out x P2) x T) (Formula 5)

[0363] In Formula 5, ceil () means rounding up. Alternatively, Formula 5 can also be, L in = max (second threshold, means rounding down. L out represents the first time length, T represents the time length of the reference period, M out represents the number of reference signals participating in out-of-sync measurement in one first time length when out-of-sync measurement is performed on the first link according to the periodic reference signal, for example, M out = 20. For parameters such as P2, please refer to the foregoing description.

[0364] For example, the first terminal device determines the first time length according to the reference period and the parameter related to the reference bandwidth.

[0365] For example, the first time length is the evaluation time length for performing synchronization measurement, that is, the first terminal device is to obtain the synchronization indication information of the first link according to the first target reference signal in at least one period included in the first time length, and then the first time length can continue to satisfy the following Formula 6:

[0366] L in = max (second threshold, ceil (M in x P3) x T) (Formula 6)

[0367] In Formula 6, ceil () means rounding up. Alternatively, Formula 6 can also be, L in = max (second threshold, means rounding down. P3 represents a parameter related to the reference bandwidth. For example, if the reference bandwidth is less than or equal to the bandwidth of the reference signal actually received in one reference period, then P3 = 1. Alternatively, P3 = 1 / bandwidth ratio, and the bandwidth ratio is the ratio of the bandwidth of the reference signal actually received in one reference period to the reference bandwidth, that is, the bandwidth ratio = bandwidth of the reference signal actually received in one reference period / reference bandwidth. For example, the bandwidth of the reference signal actually received in one reference period is 24 RBs, and the reference bandwidth is 48 RBs, then the bandwidth ratio = 24 / 48 = 1 / 2, and P3 = 1 / bandwidth ratio, then P3 = 1 / 1 / 2 = 2. Alternatively, P3 can also be other forms of values, as long as P3 is related to the reference bandwidth. For other parameters in Formula 5, please refer to the foregoing description of other formulas.

[0368] For example, the first time length is an evaluation time length for performing out-of-sync measurement, that is, the first terminal device is to obtain out-of-sync indication information of the first link according to the first target reference signal in at least one period included in the first time length, the first time length can continue to satisfy the following formula 7:

[0369] L out = max (second threshold, ceil (M out × P3) × T) (formula 7)

[0370] In formula 7, ceil() represents rounding up. Alternatively, formula 7 can also be L out = max (second threshold, ), represents rounding down. Other parameters in formula 7 can refer to the introduction of other formulas in the foregoing.

[0371] For example, the first terminal device determines the first time length according to a reference period and a parameter related to a reference bandwidth.

[0372] For example, the first time length is an evaluation time length for performing out-of-sync measurement, that is, the first terminal device is to obtain out-of-sync indication information of the first link according to the first target reference signal in at least one period included in the first time length, the first time length can continue to satisfy the following formula 8:

[0373] L out = max (second threshold, ceil (M out × P2 × P3) × T) (formula 8)

[0374] ceil() represents rounding up. Alternatively, formula 8 can also be L out = max (second threshold, ), represents rounding down. Other parameters related to formula 8 can refer to the related introduction in the foregoing.

[0375] For example, the first time length is an evaluation time length for performing in-sync measurement, that is, the first terminal device is to obtain in-sync indication information of the first link according to the first target reference signal in at least one period included in the first time length, the first time length can continue to satisfy the following formula 9:

[0376] L in = max (second threshold, ceil (M in × P2 × P3) × T) (formula 9)

[0377] ceil() represents rounding up. Alternatively, formula 9 can also be L in = max (second threshold, ), For other parameters involved in Formula 9, please refer to the previous introduction.

[0378] After determining the first duration, the first terminal device can obtain synchronization indication information or out-of-sync indication information. The process of S33 can be completed by the physical layer of the first terminal device, for example.

[0379] For the out-of-sync measurement process, for example, the physical layer of the first terminal device is based on L out For example, the physical layer of the first terminal device performs out-of-sync measurement on the first link based on the reference signal received in L out The BLER of the PDCCH is estimated by the target reference signal in the PDCCH to obtain the out-of-sync indication information. out The BLER estimated by each target reference signal in the out , the physical layer of the first terminal device can send out-of-sync indication information to the higher layer of the first terminal device (such as the MAC layer or the radio resource control (RRC) layer, etc.).

[0380] For the synchronous measurement process, for example, the physical layer of the first terminal device is based on L in For example, the physical layer of the first terminal device performs synchronization measurement on the first link based on the reference signal received in the L in The BLER of the PDCCH is estimated by the target reference signal in the PDCCH to obtain synchronization indication information. in Among the BLERs estimated by the reference signals in the in (for example, 2%), the physical layer of the first terminal device may send synchronization indication information to the upper layer of the terminal device.

[0381] The physical layer of the first terminal device can perform measurement every second time length, and can send the evaluation information to the upper layer of the first terminal device. The second time length can be understood as the time length of the reporting interval, for example, the time length of the reporting interval is equal to the time length of the reference period. The evaluation information can include synchronization indication information or out-of-sync indication information, or include synchronization indication information and out-of-sync indication information. For example, the evaluation information can also be referred to as measurement information, or monitoring information, etc. For example, the first terminal device can determine the time length of the reporting interval by itself, that is, the time length of the reporting interval can be configured by the first terminal device, or the time length of the reporting interval can be specified by the protocol. Alternatively, the time length of the reporting interval can be configured by the second terminal device, and after the second terminal device configures the time length of the reporting interval, the second terminal device can send the time length of the reporting interval to the first terminal device, so that the first terminal device can determine the time length of the reporting interval. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the time length of the reporting interval can also be configured by the network device (for example, the base station), and after the network device configures the time length of the reporting interval, the network device can send the reporting interval to the first terminal device, so that the first terminal device can determine the time length of the reporting interval. For example, the time length of the reporting interval can be greater than or equal to the time length of the reference period, for example, the time length of the reporting interval can be equal to the time length of the reference period, or can also be equal to an integer multiple of the time length of the reference period. When the terminal is only configured with the time length of the reporting interval, the time length of the reference period is equal to the time length of the reporting interval.

[0382] For example, refer to Figure 6 The schematic diagram for the first terminal device to perform measurement on the first link by the physical layer. Figure 6 The part shown by the dashed box in the figure represents the first time length, for example, the first time length includes 6 reference periods, which are represented as RS0-RS5 respectively. Figure 6 Taking one reference period as 20ms for example. Figure 6 The hatched box in the figure represents the target reference signal, and it should be noted that Figure 6 The target reference signal in the figure is only schematic and does not represent the actual position or time domain length of the target reference signal. It can be seen that the hatched box is not included in the reference period RS0, the reference period RS2 and the reference period RS4, which may be because the first terminal device does not receive the reference signal for wireless link measurement from the second terminal device in the three reference periods, that is, among the 6 reference periods, RS1, RS3 and RS5 belong to at least one reference period, and the first terminal device obtains 3 target reference signals in at least one reference period. For example, the reporting interval is equal to the reference period, so at the end of each reference period, the physical layer of the first terminal device can perform measurement and report the evaluation information to the upper layer. Figure 7The reporting occasions are the time instants when the first terminal device performs measurements and reports evaluation information to the higher layer. It can be seen that Figure 6 Two reporting occasions are shown in FIG. 3, and the interval between the two reporting occasions is the reporting interval, i.e., a reference period. For example, the first terminal device performs evaluation at the first reporting occasion shown in FIG. 3, and the measurement is performed according to all target reference signals included in the dashed box. If the first terminal device performs measurement at the second reporting occasion shown in FIG. 3, the position of the dashed box is moved to the right by one reference period, and the first terminal device performs measurement according to all target reference signals included in the moved dashed box. Figure 6 Figure 6

[0383] S35, the first terminal device determines whether the first link fails according to the synchronization indication information or the out-of-sync indication information.

[0384] After obtaining the synchronization indication information or the out-of-sync indication information, the first terminal device can determine whether the first link fails.

[0385] For example, the process of S33 can be completed by the physical layer of the first terminal device, i.e., the physical layer of the first terminal device can obtain the synchronization indication information or the out-of-sync indication information. If the physical layer of the first terminal device obtains the synchronization indication information, the physical layer of the first terminal device can send the synchronization indication information to the higher layer of the first terminal device. Alternatively, if the physical layer of the first terminal device obtains the out-of-sync indication information, the physical layer of the first terminal device can send the out-of-sync indication information to the higher layer of the first terminal device. The synchronization indication information is, for example, a link synchronization indication, and the out-of-sync indication information is, for example, a link out-of-sync indication. The execution of S34 is, for example, the higher layer of the first terminal device.

[0386] For the higher layer of the first terminal device, if N310 link out-of-sync indications are continuously received from the physical layer, the T310 timer can be started. Before the T310 timer expires, if the higher layer can continuously receive N311 link synchronization indications from the physical layer, the higher layer considers that the first terminal device and the second terminal device have returned to the synchronization state. Alternatively, before the T310 timer expires, if the higher layer does not continuously receive N311 synchronization indications from the physical layer, it is determined that the first link fails. If it is determined that the link fails, the first terminal device can perform one or more of the following operations:

[0387] ​​The first operation: the first terminal device sends the sidelink failure report information to the network device. For example, the sidelink failure report information can be carried by a radio resource control (RRC) message, a media access control control element (MAC CE), or a physical layer channel.

[0388] The second operation: the first terminal device sends the sidelink failure report information to the second terminal device. For example, the sidelink failure report information can be carried by an RRC message, a MAC CE, or a physical layer channel.

[0389] The third operation: the first terminal device stops sending feedback information, such as hybrid automatic repeat request-ack (HARQ-ACK) information or CSI, to the second terminal device. If the second terminal device does not receive the feedback information from the first terminal device within a certain time, the second terminal device will also determine that the link fails.

[0390] As an optional way, the first terminal device can determine the validity of the evaluation information in addition to obtaining the evaluation information, which can include synchronization indication information or out-of-sync indication information. For example, the physical layer of the first terminal device can determine the validity of the evaluation information and send the validity information to the higher layer of the first terminal device when sending the evaluation information to the higher layer of the first terminal device. For example, the validity information of the evaluation information (or the validity of the evaluation information) can indicate the number of target reference signals participating in obtaining the evaluation information, for example, the more the number of reference signals participating in obtaining the evaluation information, the higher the validity of the evaluation information, and the less the number of reference signals participating in obtaining the evaluation information, the lower the validity of the evaluation information. The validity information of the evaluation information may, for example, be a specific numerical value, such as numerical values 1, 2, 3, etc. representing different validities, respectively; or the validity information of the evaluation information can simply indicate high validity or low validity. For example, the validity information of the evaluation information can be implemented by 1 bit, if the value of the 1 bit is "1", it indicates that the validity of the evaluation information is high; (for example: in a synchronization / out-of-sync evaluation period including multiple reference periods, if the target reference signal is received in the most recent reference period, the value of the 1 bit can be "1", or if the target reference signal is not received in the most recent reference period, the value of the 1 bit can be "0", for example: in a synchronization / out-of-sync evaluation period, if the number of target reference signals obtained is greater than or equal to a first threshold, the value of the 1 bit can be "1", and the first threshold is, for example, 80% (actual number of received reference signals / expected number of received reference signals), or the first threshold is, for example, 15 (actual number of received reference signals);

[0391] Then, after the higher layer of the first terminal device obtains the evaluation information and the validity information of the evaluation information, it can determine the reliability of the evaluation information, so as to determine whether to determine whether the link fails according to the evaluation information. In this way, the reliability of link measurement can be improved.

[0392] Similarly, when no reference signal is received in a reference period (or in a synchronization / out-of-sync reporting interval), the physical layer can not perform synchronization / out-of-sync measurement, skip this time of higher layer reporting, and not report synchronization or out-of-sync information, or report an indication of "no reference signal received".

[0393] In addition, consider a case that the first terminal device is very likely to not receive the reference signal for a long time, for example, when link failure occurs. Then, in order to avoid the first terminal device from continuously waiting, in the embodiment of the present application, the first terminal device can also maintain a first timer, and the timing duration of the first timer can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the timing duration of the first timer can also be configured by the network device and informed to the first terminal device, or the timing duration of the first timer can also be specified by a protocol. For example, the timing duration of the first timer is {500 ms, or 1 s, or 2 s}, or can also be other values. The first timer can be maintained by the physical layer of the first terminal device, or can also be maintained by the upper layer of the first terminal device.

[0394] If the first terminal device does not receive the reference signal for wireless link measurement within the timing duration of the first timer, the first terminal device can directly determine the first link failure when the first timer expires. In this way, the terminal device can be prevented from continuously waiting, and the link failure can be determined as soon as possible.

[0395] In addition, if the first terminal device does not receive the reference signal, or the number of received reference signals is 0, in one reference period, the first terminal device can adopt one or more of the following processing methods: the first processing method, the second processing method, the third processing method, or the fourth processing method. For example, the first terminal device can adopt the first processing method, or the first terminal device can adopt the first processing method and the second processing method, or the first terminal device can adopt the second processing method, the third processing method, and the fourth processing method, and so on. The following describes the processing methods.

[0396] The first processing method: skip the current measurement process, which can be a synchronization measurement process, or an out-of-synchronization measurement process, or a synchronization measurement process and an out-of-synchronization measurement process.

[0397] Since the current measurement process is skipped, the physical layer of the first terminal device does not send synchronization indication information to the upper layer of the first terminal device, nor does it send out-of-synchronization indication information to the upper layer of the first terminal device.

[0398] The second processing method: skip the current measurement process, which can be a synchronization measurement process, or an out-of-synchronization measurement process, or a synchronization measurement process and an out-of-synchronization measurement process.

[0399] Although the current measurement process is skipped, the physical layer of the first terminal device can still send to the upper layer of the first terminal device.

[0400] skip the in-sync / out-of-sync measurement, and feed back a fifth indication information to the higher layer, the fifth indication information is neither in-sync indication information nor out-of-sync indication information, and the fifth indication information can indicate the higher layer that no reference signal is received in the reference period.

[0401] The third processing manner: the in-sync indication information or the out-of-sync indication information can be continuously obtained.

[0402] However, the in-sync indication information or the out-of-sync indication information obtained in the reference period does not participate in the related measurement, for example, the higher layer of the first terminal device can not consider the in-sync indication information or the out-of-sync indication information obtained in the reference period when measuring the link.

[0403] The fourth processing manner: the in-sync indication information or the out-of-sync indication information can be continuously obtained.

[0404] However, the in-sync indication information or the out-of-sync indication information obtained in the reference period does not participate in the related measurement, for example, the higher layer of the first terminal device can not consider the in-sync indication information or the out-of-sync indication information obtained in the reference period when measuring the link. In addition, the physical layer of the first terminal device can also send validity information of the evaluation information to the higher layer of the first terminal device, and the evaluation information can include the in-sync indication information or the out-of-sync indication information. For the validity information, please refer to the foregoing description.

[0405] Even if the first terminal device does not receive the reference signal, the present embodiment also provides a corresponding solution.

[0406] In addition, it can be seen that the present embodiment is described for a link when describing the technical solution, and for different links, similar ways can be used for evaluation.

[0407] In the present embodiment, the first terminal device receives at least two reference signals in a reference period, and the first terminal device obtains a first target reference signal according to the at least two reference signals, and then measures according to the first target reference signal. That is, no matter how many reference signals the first terminal device receives in a reference period, the first terminal device can obtain a first target reference signal according to at least two reference signals to measure. In this way, the problem of uncertain number of aperiodic reference signals is solved, so that the first terminal device can complete the measurement of the link according to the aperiodic reference signals.

[0408] The present embodiment provides a link measurement method, please refer to Figure 7 , the flowchart of the method. In the following introduction process, the method is applied to Figure 2The network architecture shown is an example. In addition, the method can be performed by two communication devices, for example, a third communication device and a fourth communication device. Among them, the third communication device or the fourth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, and of course can also be other communication devices, such as a chip system. And the implementation of the third communication device or the fourth communication device is not limited, for example, the two communication devices can be implemented in the same form, for example, both in the form of a device, or the two communication devices can be implemented in different forms, for example, the third communication device is implemented in the form of a device, and the fourth communication device is implemented in the form of a chip system, and the like. Among them, the network device is, for example, a base station.

[0409] For ease of introduction, in the following, the method is taken as an example performed by a terminal device and a terminal device, that is, the third communication device is a terminal device (for example, referred to as a first terminal device), and the fourth communication device is a terminal device (for example, referred to as a fourth device). Because the present embodiment is taken as an example applied to a wireless communication system, the functions of the terminal device 1 in the network architecture shown below can be implemented by the first terminal device described below, and the functions of the terminal device 2 in the network architecture shown below can be implemented by the second terminal device described below. Figure 2 The network architecture shown is an example. In addition, the method can be performed by two communication devices, for example, a third communication device and a fourth communication device. Among them, the third communication device or the fourth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, and of course can also be other communication devices, such as a chip system. And the implementation of the third communication device or the fourth communication device is not limited, for example, the two communication devices can be implemented in the same form, for example, both in the form of a device, or the two communication devices can be implemented in different forms, for example, the third communication device is implemented in the form of a device, and the fourth communication device is implemented in the form of a chip system, and the like. Among them, the network device is, for example, a base station. Figure 2 The network architecture shown is an example. In addition, the method can be performed by two communication devices, for example, a third communication device and a fourth communication device. Among them, the third communication device or the fourth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, and of course can also be other communication devices, such as a chip system. And the implementation of the third communication device or the fourth communication device is not limited, for example, the two communication devices can be implemented in the same form, for example, both in the form of a device, or the two communication devices can be implemented in different forms, for example, the third communication device is implemented in the form of a device, and the fourth communication device is implemented in the form of a chip system, and the like. Among them, the network device is, for example, a base station. Figure 2 The network architecture shown is an example. In addition, the method can be performed by two communication devices, for example, a third communication device and a fourth communication device. Among them, the third communication device or the fourth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, and of course can also be other communication devices, such as a chip system. And the implementation of the third communication device or the fourth communication device is not limited, for example, the two communication devices can be implemented in the same form, for example, both in the form of a device, or the two communication devices can be implemented in different forms, for example, the third communication device is implemented in the form of a device, and the fourth communication device is implemented in the form of a chip system, and the like. Among them, the network device is, for example, a base station.

[0410] S71, the first terminal device does not receive a reference signal from the second terminal device within a third time length.

[0411] Regarding the reference period, please refer to the introduction of the embodiment shown. Figure 3

[0412] For example, the first terminal device can determine the third time length by itself, that is, the third time length can be configured by the first terminal device, or the third time length can be specified by the protocol. Alternatively, the third time length can be configured by the second terminal device, and after the second terminal device configures the third time length, it can send indication information to the first terminal device, and the indication information is used to indicate the third time length. After the first terminal device receives the indication information, it can determine the third time length. Alternatively, if the first terminal device and the second terminal device are both terminal devices, the third time length can also be configured by a network device (for example, a base station), and after the network device configures the third time length, it can send indication information to the first terminal device, and the indication information is used to indicate the third time length. After the first terminal device receives the first indication information, it can determine the third time length. For example, the third time length is 500ms, or it can also be other time length.

[0413] ​For example, the first terminal device can start a first timer, and the timing duration of the first timer is the third duration. When the first timer expires, if the first terminal device does not receive the reference signal, it means that the reference signal is not received within the third duration. The reference signal in the embodiments of the present application is a reference signal for RLM.

[0414] S72, the first terminal device determines the first link failure between the first terminal device and the second terminal device.

[0415] The first terminal device is likely to not receive the reference signal for a long time, for example, when the link fails. In order to avoid the first terminal device waiting for a long time, in the embodiments of the present application, the first terminal device can also maintain a first timer. The first timer can be maintained by the physical layer of the first terminal device, or can also be maintained by the upper layer of the first terminal device.

[0416] If the first terminal device does not receive the reference signal for wireless link measurement within the timing duration of the first timer, the first terminal device can directly determine the first link failure when the first timer expires. In this way, the terminal device can avoid waiting for a long time, and can determine the link failure as soon as possible.

[0417] Figure 3 The embodiments shown are all evaluated by the RLM process. In order to evaluate the link, in addition to the RLM method, other methods can also be used. The following will introduce other link evaluation methods through another embodiment. Figure 7 The embodiments shown are all evaluated by the RLM process. In order to evaluate the link, in addition to the RLM method, other methods can also be used. The following will introduce other link evaluation methods through another embodiment.

[0418] The embodiments of the present application provide a link evaluation method, please refer to Figure 8 , the flowchart of the method. In the following introduction, the method is applied to Figure 2 the network architecture shown as an example. In addition, the method can be executed by two communication devices, for example, the fifth communication device and the sixth communication device. Among them, the fifth communication device or the sixth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, of course, it can also be other communication devices, such as chip system. And the implementation of the fifth communication device or the sixth communication device is not limited, for example, the two communication devices can be realized in the same form, for example, both through the form of device, or the two communication devices can also be realized in different forms, for example, the fifth communication device is realized through the form of device, and the sixth communication device is realized through the form of chip system, etc. Among them, the network device is, for example, a base station.

[0419] For ease of introduction, in the following, the method is taken as an example of being performed by a terminal device and a terminal device, that is, the fifth communication apparatus is taken as a terminal device (for example, referred to as a first terminal apparatus), and the sixth communication apparatus is taken as a terminal device (for example, referred to as a fourth device). Because the embodiment is taken as an example of being applied to the network architecture shown in FIG. 1, the first terminal apparatus described in the following can be the terminal device 1 in the network architecture shown in FIG. 1, and the second terminal apparatus described in the following can be the terminal device 2 in the network architecture shown in FIG. 1. Figure 2 For ease of introduction, in the following, the method is taken as an example of being performed by a terminal device and a terminal device, that is, the fifth communication apparatus is taken as a terminal device (for example, referred to as a first terminal apparatus), and the sixth communication apparatus is taken as a terminal device (for example, referred to as a fourth device). Because the embodiment is taken as an example of being applied to the network architecture shown in FIG. 1, the first terminal apparatus described in the following can be the terminal device 1 in the network architecture shown in FIG. 1, and the second terminal apparatus described in the following can be the terminal device 2 in the network architecture shown in FIG. 1. Figure 2 For ease of introduction, in the following, the method is taken as an example of being performed by a terminal device and a terminal device, that is, the fifth communication apparatus is taken as a terminal device (for example, referred to as a first terminal apparatus), and the sixth communication apparatus is taken as a terminal device (for example, referred to as a fourth device). Because the embodiment is taken as an example of being applied to the network architecture shown in FIG. 1, the first terminal apparatus described in the following can be the terminal device 1 in the network architecture shown in FIG. 1, and the second terminal apparatus described in the following can be the terminal device 2 in the network architecture shown in FIG. 1. Figure 2 For ease of introduction, in the following, the method is taken as an example of being performed by a terminal device and a terminal device, that is, the fifth communication apparatus is taken as a terminal device (for example, referred to as a first terminal apparatus), and the sixth communication apparatus is taken as a terminal device (for example, referred to as a fourth device). Because the embodiment is taken as an example of being applied to the network architecture shown in FIG. 1, the first terminal apparatus described in the following can be the terminal device 1 in the network architecture shown in FIG. 1, and the second terminal apparatus described in the following can be the terminal device 2 in the network architecture shown in FIG. 1.

[0420] S81, the first terminal apparatus updates the counter according to a demodulation situation of the first signal from the second terminal apparatus.

[0421] The counter can be configured for the first terminal apparatus, and an initial value of the counter can be greater than 0, for example, the initial value is 20, or other values, or the initial value of the counter can also be equal to 0. The initial value of the counter can be configured by the first terminal apparatus, or configured by the second terminal apparatus and informed to the first terminal apparatus, or if the second terminal apparatus is a terminal device, the initial value of the counter can also be configured by a network device and informed to the first terminal apparatus. Or the initial value of the counter can also be specified by a protocol.

[0422] The first signal can be a control signal, for example, an SCI carried on a physical sidelink control channel (PSCCH); or the first signal can also be a data signal, for example, data carried on a physical sidelink shared channel (PSSCH).

[0423] If the first signal is a control signal, the first terminal apparatus updating the counter according to the demodulation situation of the first signal from the second terminal apparatus can include: if the first terminal apparatus successfully demodulates the first signal (that is, the CRC check is successful), the first terminal apparatus can increase the value of the counter by a first value, or if the first terminal apparatus misses the first signal, the first terminal apparatus can decrease the value of the counter by a second value. Wherein, missing the first signal can also be regarded as failing to demodulate the first signal, and thus the first terminal apparatus missing the first signal can also be regarded as a kind of demodulation situation of the first terminal apparatus.

[0424] The first value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the first value can also be configured by the network device and informed to the first terminal device. Or the first value can also be specified by the protocol. The first value is, for example, 1, or can also be other values.

[0425] Similarly, the second value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the second value can also be configured by the network device and informed to the first terminal device. Or the second value can also be specified by the protocol. The second value is, for example, 3, or can also be other values. If the first value = 1 and the second value = 3, the first value is less than the second value, but here is just an example, in fact, the size relationship between the first value and the second value is not limited, for example, the second value can also be less than the first value, or the second value can also be equal to the first value.

[0426] In addition, when the first terminal device does not detect a certain time slot or subframe (for example, because the first terminal device transmits data in the time slot or subframe, and the first terminal device cannot receive data at the same time as the first terminal device transmits data), the missed detection count needs to be subtracted or deducted. For example, when the first terminal device detects that Y control channels are missed from the xth time slot to the x+kth time slot, but the first terminal device transmits N times of data between the xth time slot and the x+kth time slot, the actual number of missed detections should be Y-N. Wherein Y and N are integers greater than or equal to 0.

[0427] If the first signal is a data signal, the retransmission of the data can be considered when updating the counter.

[0428] The first signal is a data signal, and the first signal is initial transmission data. Then, the first terminal device updates the counter according to the demodulation of the first signal from the second terminal device, which can include: if the first terminal device demodulates the first signal successfully, the first terminal device can increase the value of the counter by a third value, or if the first terminal device demodulates the first signal unsuccessfully, the first terminal device can decrease the value of the counter by a fourth value.

[0429] The third value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the third value can also be configured by the network device and informed to the first terminal device. Or the third value can also be specified by the protocol. The third value is, for example, 2, or can also be other values.

[0430] Similarly, the fourth value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the fourth value can also be configured by the network device and informed to the first terminal device. Or the fourth value can also be specified by the protocol. The fourth value is, for example, 1, or can also be other values. If the third value = 2 and the fourth value = 1, the third value is greater than the fourth value, but here is just an example, in fact, the size relationship between the third value and the fourth value is not limited, for example, the fourth value can also be greater than the third value, or the fourth value can also be equal to the third value.

[0431] Alternatively, the first signal is a data signal, and the first signal is a retransmitted data. Then, the first terminal device updates the counter according to the demodulation of the first signal from the second terminal device, which can include: if the first terminal device successfully demodulates the first signal, the first terminal device can increase the value of the counter by a fifth value, or if the first terminal device fails to demodulate the first signal, the first terminal device can decrease the value of the counter by a sixth value.

[0432] Wherein, the fifth value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the fifth value can also be configured by the network device and informed to the first terminal device. Or the fifth value can also be specified by the protocol. The fifth value is, for example, 1, or can also be other values.

[0433] Similarly, the sixth value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the sixth value can also be configured by the network device and informed to the first terminal device. Or the sixth value can also be specified by the protocol. The sixth value is, for example, 2, or can also be other values. If the fifth value = 1 and the sixth value = 2, the fifth value is less than the sixth value, but here is just an example, in fact, the size relationship between the fifth value and the sixth value is not limited, for example, the sixth value can also be less than the fifth value, or the sixth value can also be equal to the fifth value.

[0434] In addition, in the above introduction process of the first value, the second value, the third value, the fourth value, the fifth value and the sixth value, the values of these values are only some examples, and in fact, the size relationship between the values is not limited.

[0435] S82, the first terminal device determines whether the link between the first terminal device and the second terminal device fails according to the value of the counter.

[0436] The initial value of the counter can be greater than 0, or the initial value of the counter can also be equal to 0. For example, if the initial value of the counter is greater than 0, when the value of the counter is 0, the first terminal device can consider that the link with the second terminal device fails. Or if the initial value of the counter is 0, when the value of the counter is the seventh value, the first terminal device can consider that the link with the second terminal device fails. The seventh value can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the seventh value can also be configured by the network device and informed to the first terminal device. Or the seventh value can also be specified by a protocol. The seventh value is, for example, 20, or can also be other values.

[0437] In the embodiment of the application, the first terminal device can evaluate the link according to the demodulation of the signal from the second terminal device, that is, the decoding result of the PSSCH / PSCCH is used to evaluate the link, which reduces the complexity in design and implementation.

[0438] In the foregoing, to evaluate the link, in addition to the RLM mode, other modes can also be used. In addition to the mode introduced in the embodiment shown in Figure 8 In addition to the mode introduced in the embodiment shown in

[0439] The embodiment of the application provides a link evaluation method, please refer to Figure 9 , which is a flowchart of the method. In the following introduction, the network architecture shown in Figure 2 is taken as an example. In addition, the method can be executed by two communication devices, for example, the fifth communication device and the sixth communication device. Among them, the fifth communication device or the sixth communication device can be a network device or a communication device capable of supporting the network device to realize the functions required by the method, or can be a terminal device or a communication device capable of supporting the terminal device to realize the functions required by the method, of course, it can also be other communication devices, such as chip system. And the implementation of the fifth communication device or the sixth communication device is not limited, for example, the two communication devices can be realized in the same form, for example, both are realized in the form of device, or the two communication devices can also be realized in different forms, for example, the fifth communication device is realized in the form of device, and the sixth communication device is realized in the form of chip system, etc. Among them, the network device is, for example, a base station.

[0440] In order to facilitate the introduction, in the following, the method executed by the terminal device and the terminal device is taken as an example, that is, the fifth communication device is a terminal device (for example, called the first terminal device), and the sixth communication device is a terminal device (for example, called the fourth device). Because the embodiment is taken as an example of application in Figure 2The network architecture shown is an example, and therefore, the first terminal device described below can be Figure 2 The terminal device 1 in the network architecture shown, the second terminal device described below can be Figure 2 The terminal device 2 in the network architecture shown.

[0441] S91, the first terminal device obtains a channel busy ratio in a second time length according to the number of the first type of channels and the total number of channels between the first terminal device and the second terminal device, the first type of channels including channels with signal strength greater than or equal to a first threshold in the second time length.

[0442] For example, in V2X, the network device will initially configure the channels that need to be used for the terminal device, and the total number of channels configured by the network device can be used as the total number of channels described in S91. The first terminal device can determine the number of the first type of channels, which can include channels with signal strength greater than or equal to a first threshold in the second time length. Because the second time length is used as the time length, the first type of channels can include channels with average signal strength greater than or equal to the first threshold in the second time length. The first threshold can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the first threshold can also be configured by the network device and informed to the first terminal device. Or the first threshold can also be specified by a protocol.

[0443] Wherein, the channel busy ratio is represented by CR for example, then CR = N1 / N2, wherein N1 represents the number of the first type of channels, and N2 represents the total number of channels.

[0444] S92, the first terminal device performs synchronization evaluation or out-of-sync evaluation on the link between the first terminal device and the second terminal device according to the channel busy ratio.

[0445] For example, if the channel busy ratio is greater than or equal to a second threshold, the first terminal device determines that the link is out-of-sync, or if the channel busy ratio is less than or equal to a third threshold, the first terminal device determines that the link is in-sync. Because the evaluation of the link generally occurs before the first terminal device transmits data, if the channel busy ratio is greater than or equal to the second threshold before the first terminal device transmits data, it is very likely that the link has failed, and therefore the first terminal device can determine whether the link is out-of-sync based on this.

[0446] For example, the processes of S91 and S92 can be performed by the physical layer of the first terminal device, then if the physical layer of the first terminal device determines that the link is out of synchronization, the physical layer of the first terminal device can send a link out-of-synchronization indication to the higher layer of the first terminal device, or if the physical layer of the first terminal device determines that the link is in synchronization, the physical layer of the first terminal device can send a link in-synchronization indication to the higher layer of the first terminal device. The higher layer of the first terminal device can determine whether the link fails according to the link in-synchronization indication or the link out-of-synchronization indication.

[0447] For example, for the higher layer of the first terminal device, if N310 link out-of-synchronization indications from the physical layer are continuously received, the T310 timer can be started. Before the T310 timer expires, if the higher layer can continuously receive N311 link in-synchronization indications from the physical layer, the higher layer considers that the first terminal device and the second terminal device have returned to the synchronization state. Or, before the T310 timer expires, if the higher layer does not continuously receive N311 in-synchronization indications from the physical layer, it is determined that the first link fails. If it is determined that the link fails, the first terminal device can perform one or more of the following operations:

[0448] The first operation: the first terminal device sends sidelink failure report information to the network device. For example, the sidelink failure report information can be carried by a radio resource control (RRC) message, a media access control control element (MAC CE), or a physical layer channel.

[0449] The second operation: the first terminal device sends sidelink failure report information to the second terminal device. For example, the sidelink failure report information can be carried by an RRC message, a MAC CE, or a physical layer channel.

[0450] The third operation: the first terminal device stops sending feedback information, such as hybrid automatic repeat request-ack (HARQ-ACK) information or CSI, to the second terminal device. If the second terminal device does not receive feedback information from the first terminal device within a certain time, the second terminal device also determines that the link fails.

[0451] The second threshold can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the second threshold can also be configured by the network device and informed to the first terminal device. Or the second threshold can also be specified by a protocol. For example, the second threshold is 70%, or it can also be other values.

[0452] Similarly, the third threshold can be configured by the first terminal device, or configured by the second terminal device and informed to the first terminal device, or if the second terminal device is a terminal device, the third threshold can also be configured by the network device and informed to the first terminal device. Or the third threshold can also be specified by a protocol. For example, the third threshold is 40%, or it can also be other values.

[0453] It can be seen that the channel busy ratio is likely to take a value in the range of (40%, 70%), and if the channel busy ratio is in this range, the first terminal device neither considers the link to be in synchronization nor considers the link to be out of synchronization, but will continue to evaluate.

[0454] In the embodiments of the present application, the link can be evaluated according to the channel busy ratio, which is simple and reduces the complexity of design and implementation.

[0455] In addition, Figure 9 The embodiments shown can also be combined with Figure 3 the embodiments shown. For example, the physical layer of the first terminal device can obtain evaluation information, for example, referred to as first evaluation information, according to the manner provided by Figure 3 the embodiments shown, and also obtain evaluation information, for example, referred to as second evaluation information, according to the manner provided by Figure 9 the embodiments shown, and when the physical layer of the first terminal device sends the first evaluation information obtained according to the manner provided by Figure 3 the embodiments shown to the high layer of the first terminal device, the physical layer of the first terminal device also sends the validity information of the first evaluation information to the high layer of the first terminal device. Then, after the high layer of the first terminal device obtains the first evaluation information and the second evaluation information, if the validity information of the first evaluation information indicates that the validity of the first evaluation information is high, or indicates that the first evaluation information is valid, the high layer of the first terminal device can select to determine whether the link with the second terminal device fails according to the first evaluation information. Or, if the validity information of the first evaluation information indicates that the validity of the first evaluation information is low, or indicates that the first evaluation information is invalid, the high layer of the first terminal device can select to determine whether the link with the second terminal device fails according to the second evaluation information.

[0456] Or, the physical layer of the first terminal device can obtain the first evaluation information according to the manner provided by Figure 3 the embodiments shown, and also obtain the second evaluation information according to the manner provided by Figure 9The embodiments shown provide a way to obtain the second evaluation information. If the physical layer of the first terminal device considers that the validity of the first evaluation information is high, or the first evaluation information is valid, the physical layer of the first terminal device can send the first evaluation information to the high layer of the first terminal device, and does not send the second evaluation information to the high layer of the first terminal device. Then, the high layer of the first terminal device can directly determine whether the link with the second terminal device fails according to the first evaluation information. Or, if the physical layer of the first terminal device considers that the validity of the first evaluation information is low, or the first evaluation information is invalid, the physical layer of the first terminal device can send the second evaluation information to the high layer of the first terminal device, and does not send the first evaluation information to the high layer of the first terminal device. Then, the high layer of the first terminal device can directly determine whether the link with the second terminal device fails according to the second evaluation information.

[0457] If the first evaluation information includes synchronization indication information, the second evaluation information includes synchronization indication information, or if the first evaluation information includes out-of-sync indication information, the second evaluation information includes out-of-sync indication information.

[0458] By combining the two embodiments, the first terminal device can make more reliable evaluation on whether the link fails.

[0459] In the foregoing, to evaluate the link, in addition to the RLM mode, other modes can also be used. In addition to the modes introduced in the foregoing embodiments of the first terminal device, the following embodiment introduces another link evaluation mode. Figure 8 The embodiments shown or Figure 9 In addition to the modes introduced in the foregoing embodiments, the following embodiment introduces another link evaluation mode. Different from the foregoing embodiments, the link evaluation modes introduced in the foregoing embodiments are performed by the first terminal device, while in this embodiment, the second terminal device performs the link evaluation.

[0460] The embodiments of the present application provide a link evaluation method, please refer to Figure 10 , the flowchart of the method. In the following introduction process, the method is applied to Figure 2Take the network architecture shown as an example. In addition, the method can be performed by two communication devices, such as the seventh communication device and the eighth communication device. Among them, the seventh communication device or the eighth communication device can be a network device or a communication device that can support the network device to implement the functions required by the method, or can be a terminal device or a communication device that can support the terminal device to implement the functions required by the method, and of course it can also be other communication devices, such as a chip system. There is no restriction on the implementation method of the seventh communication device or the eighth communication device. For example, the two communication devices can be implemented in the same form, such as both are implemented in the form of devices, or the two communication devices can also be implemented in different forms, such as the seventh communication device is implemented in the form of a device, and the eighth communication device is implemented in the form of a chip system, and so on. Among them, the network device is, for example, a base station.

[0461] For the sake of convenience, the following takes the method executed by a terminal device and a terminal device as an example, that is, the seventh communication device is a terminal device (for example, called the first terminal device) and the eighth communication device is a terminal device (for example, called the fourth device) as an example. Figure 2 As an example, the network architecture shown in FIG. 1 is used. Therefore, the first terminal device described below may be Figure 2 In the network architecture shown in FIG. 1 , the second terminal device described below may be Figure 2 Terminal device 2 in the network architecture shown.

[0462] S101: The physical layer of the second terminal device performs synchronization evaluation or out-of-synchronization evaluation on the link between the first terminal device and the second terminal device according to feedback information received from the first terminal device.

[0463] For example, the second terminal device can obtain the first time length, and when performing the evaluation, the second terminal device can perform the evaluation based on the feedback information received within the first time length. The first time length can adopt a default value, such as 200ms, or the first time length can also be referred to Figure 3 The first duration is described in the embodiment shown. As for how the second terminal device obtains the first duration, please refer to Figure 3 In the embodiment shown, the first terminal device obtains the first duration. In addition, the second terminal device can also obtain a reporting interval, and the second terminal device performs synchronization evaluation or desynchronization evaluation on the link in each reporting interval. The reporting interval adopts a default value, such as 10ms, or the reporting interval can also be referred to. Figure 3 The description of the reporting interval in the embodiment shown in FIG. Figure 3 The embodiment shown shows a method in which the first terminal device obtains the reporting interval.

[0464] The feedback information includes, for example, HARQ-ACK, which can include an acknowledgement (ACK) or a negative acknowledgement (NACK). The second terminal device performs a synchronization evaluation or an out-of-synchronization evaluation on the link between the first terminal device and the second terminal device according to the received feedback information from the first terminal device. There can be different evaluation manners, which are described below by way of example.

[0465] The first evaluation manner is that if N1 / N is greater than a first threshold, the second terminal device considers that the link between the first terminal device and the second terminal device is in synchronization, or if N1 / N is less than a second threshold, the second terminal device considers that the link between the first terminal device and the second terminal device is out of synchronization. Here, N1 represents the number of ACKs received by the second terminal device within a first time length, and N represents the total number of HARQ-ACKs expected to be received by the second terminal device within the first time length.

[0466] The first threshold can be configured by the second terminal device, or configured by the first terminal device and notified to the second terminal device, or if the second terminal device is a terminal device, the first threshold can also be configured by a network device and notified to the second terminal device. Or the first threshold can also be specified by a protocol. For example, the first threshold is 80%, or it can also be other values. Similarly, the second threshold can be configured by the second terminal device, or configured by the first terminal device and notified to the second terminal device, or if the second terminal device is a terminal device, the second threshold can also be configured by a network device and notified to the second terminal device. Or the second threshold can also be specified by a protocol. For example, the second threshold is 20%, or it can also be other values.

[0467] The second evaluation manner is that if N2 / N is less than a third threshold (for example, 20%), the second terminal device considers that the link between the first terminal device and the second terminal device is in synchronization, or if N2 / N is greater than a fourth threshold (for example, 80%), the second terminal device considers that the link between the first terminal device and the second terminal device is out of synchronization. Here, N2 represents the number of NACKs received by the second terminal device within the first time length, and N represents the total number of HARQ-ACKs expected to be received by the second terminal device within the first time length.

[0468] The third threshold can be configured by the second terminal device, or configured by the first terminal device and informed to the second terminal device, or if the second terminal device is a terminal device, the third threshold can also be configured by the network device and informed to the second terminal device. Or the third threshold can also be specified by the protocol. For example, the third threshold is 20%, or it can also be other values. Similarly, the fourth threshold can be configured by the second terminal device, or configured by the first terminal device and informed to the second terminal device, or if the second terminal device is a terminal device, the fourth threshold can also be configured by the network device and informed to the second terminal device. Or the fourth threshold can also be specified by the protocol. For example, the fourth threshold is 80%, or it can also be other values.

[0469] The third evaluation method: if N2 / N1 is less than a fifth threshold (such as 10%), the second terminal device considers that the link with the first terminal device is in synchronization, or if N2 / N1 is greater than a sixth threshold, the second terminal device considers that the link with the first terminal device is out of synchronization (such as 50%). N2 represents the number of NACKs received by the second terminal device within the first time length, and N1 represents the number of ACKs received by the second terminal device within the first time length.

[0470] The fifth threshold can be configured by the second terminal device, or configured by the first terminal device and informed to the second terminal device, or if the second terminal device is a terminal device, the fifth threshold can also be configured by the network device and informed to the second terminal device. Or the fifth threshold can also be specified by the protocol. For example, the fifth threshold is 10%, or it can also be other values. Similarly, the sixth threshold can be configured by the second terminal device, or configured by the first terminal device and informed to the second terminal device, or if the second terminal device is a terminal device, the sixth threshold can also be configured by the network device and informed to the second terminal device. Or the sixth threshold can also be specified by the protocol. For example, the sixth threshold is 50%, or it can also be other values.

[0471] Wherein, N=N1+N2+Y. Y represents the number of data that has not received any feedback, that is, for the data sent by the second terminal device to the first terminal device, there may be data that neither receives ACK from the first terminal device nor receives NACK from the first terminal device, then these data belong to Y data.

[0472] S102, the physical layer of the second terminal device sends synchronization indication information and / or out-of-synchronization indication information to the upper layer of the second terminal device, wherein the synchronization indication information is obtained by synchronously evaluating the link, and the out-of-synchronization indication information is obtained by out-of-synchronization evaluating the link.

[0473] The physical layer of the second terminal device can obtain the synchronization indication information or the out-of-synchronization indication information. If the synchronization indication information is obtained, the physical layer of the second terminal device can send the synchronization indication information to the upper layer of the second terminal device. If the out-of-synchronization indication information is obtained, the physical layer of the second terminal device can send the out-of-synchronization indication information to the upper layer of the second terminal device. The synchronization indication information is, for example, a link synchronization indication. The out-of-synchronization indication information is, for example, a link out-of-synchronization indication. The upper layer of the second terminal device is, for example, a MAC layer or an RRC layer.

[0474] For the upper layer of the second terminal device, if N310 link out-of-synchronization indications are continuously received from the physical layer, the T310 timer can be started. Before the T310 timer expires, if the upper layer can continuously receive N311 link synchronization indications from the physical layer, the upper layer considers that the first terminal device and the second terminal device return to the synchronization state. Or, before the T310 timer expires, if the upper layer does not continuously receive N311 synchronization indications from the physical layer, it is determined that the first link fails. If it is determined that the link fails, the second terminal device can perform one or more of the following operations:

[0475] The first operation: the second terminal device sends sidelink failure report information to the network device. The sidelink failure report information can be carried by, for example, an RRC message, a MAC CE, or a physical layer channel.

[0476] The second operation: the second terminal device sends sidelink failure report information to the first terminal device. The sidelink failure report information can be carried by, for example, an RRC message, a MAC CE, or a physical layer channel.

[0477] In the embodiments of the present application, the second terminal device can evaluate the link, so that the sending end or the receiving end of the data can evaluate the link, which is more flexible. Moreover, the evaluation method provided in the embodiments of the present application is simple and easy to implement.

[0478] The device used to implement the above method in the embodiments of the present application will be described below with reference to the accompanying drawings. Therefore, the content in the foregoing can be used in the subsequent embodiments, and the repeated content will not be described herein.

[0479] Figure 11 A schematic block diagram of the communication device 1100 provided in the embodiments of the present application is shown. The communication device 1100 is, for example, the first terminal device 1100.

[0480] The first terminal device 1100 includes a processing module 1110 and a transceiver module 1120. Exemplarily, the first terminal device 1100 may be a terminal device, or a chip used in a terminal device, or other combined device, component, etc. having the functions of the aforementioned terminal device. When the first terminal device 1100 is a terminal device, the transceiver module 1120 may be a transceiver, which may include an antenna and a radio frequency circuit, etc., and the processing module 1110 may be a processor, such as a baseband processor, which may include one or more central processing units (CPUs). When the first terminal device 1100 is a component having the aforementioned terminal functions, the transceiver module 1120 may be a radio frequency unit, and the processing module 1110 may be a processor, such as a baseband processor. When the first terminal device 1100 is a chip system, the transceiver module 1120 may be an input / output interface of the chip system (e.g., a baseband chip), and the processing module may be a processor of the chip system, which may include one or more central processing units.

[0481] The processing module 1110 can be used to execute Figure 3 In the embodiment shown, all operations except the transceiver operations performed by the first terminal device, such as S31, S33, S34 and S35, and / or other processes for supporting the technology described herein. The transceiver module 1120 can be used to perform Figure 3 In the illustrated embodiment, all transceiver operations performed by the first terminal device, such as S32 , and / or other processes for supporting the technology described herein.

[0482] In addition, the transceiver module 1120 may be a functional module that can perform both sending and receiving operations. For example, the transceiver module 1120 may be used to perform Figure 3 In the embodiment shown, all sending operations and receiving operations performed by the first terminal device, for example, when performing a sending operation, the transceiver module 1120 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1120 can be considered as a receiving module; or, the transceiver module 1120 can also be a general term for two functional modules, which are a sending module and a receiving module, respectively. The sending module is used to complete the sending operation, for example, the sending module can be used to perform Figure 3 In the embodiment shown, all sending operations are performed by the first terminal device, and the receiving module is used to complete the receiving operation. For example, the receiving module can be used to perform Figure 3 The embodiment shown shows all receiving operations performed by the first terminal device.

[0483] For example, the transceiver 1120 is configured to receive at least one reference signal from a second terminal device in a first reference period, the at least one reference signal being aperiodic, or the at least one reference signal being irregular.

[0484] The processing module 1110 is configured to determine a first target reference signal in the first reference period according to the at least one reference signal.

[0485] The processing module 1110 is further configured to obtain synchronization indication information or out-of-sync indication information of a first link according to at least one target reference signal in at least one reference period, the first link being a link between the first terminal device 1100 and the second terminal device, the at least one reference period including the first reference period, and the at least one target reference signal including the first target reference signal.

[0486] As an optional implementation, the processing module 1110 is further configured to determine whether the first link fails according to the synchronization indication information or the out-of-sync indication information.

[0487] As an optional implementation, the processing module 1110 is configured to determine the first target reference signal in the first reference period according to the at least one reference signal in the following manner:

[0488] determining one of the at least one reference signal as the first target reference signal; or,

[0489] combining part or all of the at least one reference signal to obtain the first target reference signal.

[0490] As an optional implementation, the processing module 1110 is configured to determine the first target reference signal in the first reference period according to the at least one reference signal in the following manner:

[0491] in a case where a cumulative density of a first N reference signals in the at least one reference signal is greater than or equal to a reference density, taking the first N reference signals as the first target reference signal, N being greater than or equal to 1, wherein the density of a reference signal is a number of frequency domain units carrying the reference signal in a bandwidth occupied by the reference signal, and the cumulative density of the reference signal is a sum of densities of one or more reference signals; or,

[0492] in a case where a cumulative bandwidth of a first N reference signals in the at least one reference signal is greater than or equal to a reference bandwidth, taking the first N reference signals as the first target reference signal, N being greater than or equal to 1.

[0493] As an optional implementation,

[0494] The processing module 1110 is further configured to determine the duration of the reference period; or,

[0495] The transceiver module 1120 is further configured to receive first indication information from the second terminal device, where the first indication information is used to indicate a duration of the reference period.

[0496] As an optional embodiment, the processing module 1110 is used to determine the length of the reference period in the following manner: determining the length of the reference period based on the parameters of the data packet of the first service, the data packet of the first service is transmitted through the first link, and the parameters of the data packet of the first service include the expected cycle length of the data packet of the first service, and / or include retransmission configuration information of the data packet of the first service.

[0497] As an optional implementation manner, the duration of the reference period satisfies:

[0498] T=min(first threshold,ceil(T packet ×P1));

[0499] Wherein, T represents the duration of the reference period, the first threshold is a constant, and T packet represents the minimum expected cycle duration of the data packet of the first service, P1 represents the retransmission configuration information of the first service, and ceil() represents the rounding-up operation.

[0500] As an optional implementation, the value of P1 includes one or any combination of the following:

[0501] When the first service is not retransmitted, P1=2;

[0502] When the first service is blindly retransmitted, P1=2 / N1, where N1 represents the number of times a data packet included in the first service is blindly retransmitted; or

[0503] When the first service performs HARQ adaptive retransmission, P1=2 / N2, where N2 represents the expected number of HARQ adaptive retransmissions for a data packet included in the first service.

[0504] As an optional embodiment, the processing module 1110 is used to obtain synchronization indication information or out-of-sync indication information of the first link based on at least one target reference signal in at least one reference period in the following manner: obtaining synchronization indication information or out-of-sync indication information of the first link based on at least one target reference signal in the at least one reference period included in the first time length, where the at least one reference period is at least one reference period in which a reference signal is received among all reference periods in the first time length.

[0505] As an optional implementation,

[0506] The processing module 1110 is further configured to determine the first time length according to a time length of the reference period; or,

[0507] The transceiver module 1120 is further configured to receive second indication information from the second terminal device, the second indication information being used to indicate the first time length.

[0508] As an optional implementation,

[0509] The processing module 1110 obtains synchronization indication information of the first link according to at least one target reference signal in the at least one reference period included in the first time length; and the processing module 1110 is configured to determine the first time length according to a time length of the reference period in the following manner:

[0510] determining that the first time length satisfies: L in = max(100, M in × T), L in denotes the first time length, M in denotes a number of periodic reference signals participating in synchronization measurement in one of the first time lengths when the first link is measured for synchronization according to the periodic reference signals, and T denotes the time length of the reference period; or,

[0511] The processing module 1110 obtains out-of-sync indication information of the first link according to at least one target reference signal in the at least one reference period included in the first time length; and the processing module 1110 is configured to determine the first time length according to a time length of the reference period in the following manner:

[0512] determining that the first time length satisfies: L out = max(200, M out × T), L out denotes the first time length, M out denotes a number of periodic reference signals participating in out-of-sync measurement in one of the first time lengths when the first link is measured for out-of-sync according to the periodic reference signals, and T denotes the time length of the reference period.

[0513] As an optional implementation, the processing module 1110 is configured to determine the first time length according to the time length of the reference period in the following manner: determining the first time length according to the time length of the reference period and a first parameter, the first parameter including a reference density and / or a reference bandwidth, the reference density being used to determine the target reference signal, and the reference bandwidth being used to determine the target reference signal.

[0514] As an optional implementation, the processing module 1110 is configured to determine the first time length according to the reference period and a parameter related to a reference density in the following manner:

[0515] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P2) × T), L in denotes the first time length, T denotes a time length of the reference period, M in denotes a number of reference signals participating in synchronization measurement within one of the first time lengths when performing synchronization measurement on the first link according to the periodic reference signals, and P2 denotes the parameter related to the reference density; or

[0516] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P2) × T), L out denotes the first time length, T denotes a time length of the reference period, M out denotes a number of reference signals participating in out-of-sync measurement within one of the first time lengths when performing out-of-sync measurement on the first link according to the periodic reference signals, and P2 denotes the parameter related to the reference density.

[0517] As an optional implementation, the processing module 1110 is configured to determine the first time length according to the reference period and a parameter related to a reference bandwidth in the following manner:

[0518] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in × P3) × T), L in denotes the first time length, T denotes the reference period, M in denotes a number of reference signals participating in synchronization measurement within one of the first time lengths when performing synchronization measurement on the first link according to the periodic reference signals, and P3 denotes the parameter related to the reference bandwidth; or

[0519] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L out = max (second threshold, ceil (M out × P3) × T), L out denotes the first time length, T denotes the reference period, M outP3 represents a parameter related to the reference bandwidth.

[0520] As an optional implementation, the processing module 1110 is configured to determine the first time length according to the reference period, the transmission related to the reference density, and the parameter related to the reference bandwidth, by:

[0521] The first time length is used to obtain the in-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M in x P2 x P3) x T) L in L represents the first time length, T represents the reference period, M in P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth; or,

[0522] The first time length is used to obtain the out-of-sync indication information, and the first time length satisfies the following formula: L in = max (second threshold, ceil (M out x P2 x P3) x T) L in L represents the first time length, T represents the reference period, M out P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth.

[0523] As an optional implementation, the processing module 1110 is further configured to determine validity information, the validity information being used to indicate validity of the in-sync indication information or validity of the out-of-sync indication information, wherein the more the number of the at least one reference period, the higher the validity of the in-sync indication information or the out-of-sync indication information.

[0524] As an optional implementation, the processing module 1110 is further configured to maintain a first timer, the first timer being used to determine the link failure when the first timer expires if no reference signal is received within a timing duration of the first timer.

[0525] It should be understood that the processing module 1110 in the embodiments of the present application can be realized by a processor or a processor-related circuit component, and the transceiver module 1120 can be realized by a transceiver or a transceiver-related circuit component.

[0526] As Figure 12 shown in FIG. 12, embodiments of the present application further provide a communication apparatus 1200. Exemplarily, the communication apparatus 1200 is, for example, a first terminal apparatus 1200. Exemplarily, the first terminal apparatus 1200 can be a communication device, for example, a terminal device, or can also be a chip system, etc. The first terminal apparatus 1200 comprises a processor 1210, a memory 1220 and a transceiver 1230, wherein the memory 1220 stores instructions or programs, and the processor 1210 is configured to execute the instructions or programs stored in the memory 1220. When the instructions or programs stored in the memory 1220 are executed, the processor 1210 is configured to perform operations performed by the processing module 1110 in the above-described embodiments, and the transceiver 1230 is configured to perform operations performed by the transceiving module 1120 in the above-described embodiments.

[0527] The transceiver 1230 can be one functional unit which can complete both sending operation and receiving operation. For example, the transceiver 1230 can be configured to perform all sending operations and receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, for example, when performing sending operation, the transceiver 1230 can be regarded as a sender, and when performing receiving operation, the transceiver 1230 can be regarded as a receiver; or the transceiver 1230 can also be a general term of two functional units, i.e. a sender and a receiver, the sender is configured to complete sending operation, for example, the sender can be configured to perform all sending operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, and the receiver is configured to complete receiving operation, for example, the receiver can be configured to perform all receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11. Figure 3 The transceiver 1230 can be one functional unit which can complete both sending operation and receiving operation. For example, the transceiver 1230 can be configured to perform all sending operations and receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, for example, when performing sending operation, the transceiver 1230 can be regarded as a sender, and when performing receiving operation, the transceiver 1230 can be regarded as a receiver; or the transceiver 1230 can also be a general term of two functional units, i.e. a sender and a receiver, the sender is configured to complete sending operation, for example, the sender can be configured to perform all sending operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, and the receiver is configured to complete receiving operation, for example, the receiver can be configured to perform all receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11. Figure 3 The transceiver 1230 can be one functional unit which can complete both sending operation and receiving operation. For example, the transceiver 1230 can be configured to perform all sending operations and receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, for example, when performing sending operation, the transceiver 1230 can be regarded as a sender, and when performing receiving operation, the transceiver 1230 can be regarded as a receiver; or the transceiver 1230 can also be a general term of two functional units, i.e. a sender and a receiver, the sender is configured to complete sending operation, for example, the sender can be configured to perform all sending operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, and the receiver is configured to complete receiving operation, for example, the receiver can be configured to perform all receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11. Figure 3 The transceiver 1230 can be one functional unit which can complete both sending operation and receiving operation. For example, the transceiver 1230 can be configured to perform all sending operations and receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, for example, when performing sending operation, the transceiver 1230 can be regarded as a sender, and when performing receiving operation, the transceiver 1230 can be regarded as a receiver; or the transceiver 1230 can also be a general term of two functional units, i.e. a sender and a receiver, the sender is configured to complete sending operation, for example, the sender can be configured to perform all sending operations performed by the first terminal apparatus in the embodiments shown in FIG. 11, and the receiver is configured to complete receiving operation, for example, the receiver can be configured to perform all receiving operations performed by the first terminal apparatus in the embodiments shown in FIG. 11.

[0528] It should be understood that the first terminal apparatus 1100 or the first terminal apparatus 1200 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown in FIG. 11, and the operations and / or functions of each module in the first terminal apparatus 1100 or the first terminal apparatus 1200 are respectively to realize the corresponding flows in the embodiments shown in FIG. 11, which will not be described herein again for the sake of brevity. Figure 3 It should be understood that the first terminal apparatus 1100 or the first terminal apparatus 1200 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown in FIG. 11, and the operations and / or functions of each module in the first terminal apparatus 1100 or the first terminal apparatus 1200 are respectively to realize the corresponding flows in the embodiments shown in FIG. 11, which will not be described herein again for the sake of brevity. Figure 3 It should be understood that the first terminal apparatus 1100 or the first terminal apparatus 1200 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown in FIG. 11, and the operations and / or functions of each module in the first terminal apparatus 1100 or the first terminal apparatus 1200 are respectively to realize the corresponding flows in the embodiments shown in FIG. 11, which will not be described herein again for the sake of brevity.

[0529] Figure 13 A schematic block diagram of the communication apparatus 1300 according to an embodiment of the present application is shown in FIG. 13. Exemplarily, the communication apparatus 1300 is, for example, a first terminal apparatus 1300.

[0530] The first terminal device 1300 includes a processing module 1310 and a transceiver module 1320. Exemplarily, the first terminal device 1300 can be a terminal device, or can be a chip applied in the terminal device or other combination device, component, etc. having the terminal device function. When the first terminal device 1300 is a terminal device, the transceiver module 1320 can be a transceiver, which can include an antenna and a radio frequency circuit, etc., and the processing module 1310 can be a processor, for example, a baseband processor, which can include one or more central processing units (CPUs). When the first terminal device 1300 is a component having the terminal function, the transceiver module 1320 can be a radio frequency unit, and the processing module 1310 can be a processor, for example, a baseband processor. When the first terminal device 1300 is a chip system, the transceiver module 1320 can be an input / output interface of the chip system (for example, a baseband chip), and the processing module can be a processor of the chip system, which can include one or more central processing units.

[0531] The processing module 1310 can be configured to perform all operations performed by the first terminal device in the embodiments shown in the figures, for example, S71 and S72, and / or other processes for supporting the technologies described herein. Figure 7 The transceiver module 1320 can be configured to perform all operations performed by the first terminal device in the embodiments shown in the figures, for example, operations of receiving a reference signal from the second terminal device, and / or other processes for supporting the technologies described herein. Figure 7 The transceiver module 1320 can be configured to perform all operations performed by the first terminal device in the embodiments shown in the figures, for example, operations of receiving a reference signal from the second terminal device, and / or other processes for supporting the technologies described herein.

[0532] In addition, the transceiver module 1320 can be a functional module that can complete both sending operations and receiving operations. For example, the transceiver module 1320 can be configured to perform all sending operations and receiving operations performed by the first terminal device in the embodiments shown in the figures. For example, when performing a sending operation, the transceiver module 1320 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1320 can be considered as a receiving module. Figure 7 In addition, the transceiver module 1320 can be a functional module that can complete both sending operations and receiving operations. For example, the transceiver module 1320 can be configured to perform all sending operations and receiving operations performed by the first terminal device in the embodiments shown in the figures. For example, when performing a sending operation, the transceiver module 1320 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1320 can be considered as a receiving module. Figure 7 In addition, the transceiver module 1320 can be a functional module that can complete both sending operations and receiving operations. For example, the transceiver module 1320 can be configured to perform all sending operations and receiving operations performed by the first terminal device in the embodiments shown in the figures. For example, when performing a sending operation, the transceiver module 1320 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1320 can be considered as a receiving module. Figure 7 In addition, the transceiver module 1320 can be a functional module that can complete both sending operations and receiving operations. For example, the transceiver module 1320 can be configured to perform all sending operations and receiving operations performed by the first terminal device in the embodiments shown in the figures. For example, when performing a sending operation, the transceiver module 1320 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1320 can be considered as a receiving module.

[0533] For example, the processing module 1310 is configured to determine that the transceiver module does not receive a reference signal from the second terminal device within a third time period, the reference signal being used for the first terminal device 1300 to measure a first link between the first terminal device 1300 and the second terminal device.

[0534] The processing module 1310 is further configured to determine that the first link fails.

[0535] It should be understood that the processing module 1310 in the embodiments of the present application can be implemented by a processor or a processor-related circuit component, and the transceiver module 1320 can be implemented by a transceiver or a transceiver-related circuit component.

[0536] As shown in Figure 14 The embodiments of the present application also provide a communication device 1400. The communication device 1400 is, for example, a first terminal device 1400. The first terminal device 1400 can be a communication apparatus, for example, a terminal device, or can be a chip system, etc. The first terminal device 1400 includes a processor 1410, a memory 1420 and a transceiver 1430, wherein the memory 1420 stores instructions or programs, and the processor 1410 is configured to execute the instructions or programs stored in the memory 1420. When the instructions or programs stored in the memory 1420 are executed, the processor 1410 is configured to perform the operations performed by the processing module 1310 in the above-described embodiments, and the transceiver 1430 is configured to perform the operations performed by the transceiver module 1320 in the above-described embodiments.

[0537] The transceiver 1430 can be a functional unit that can complete both sending operations and receiving operations. For example, the transceiver 1430 can be configured to perform all the sending operations and receiving operations performed by the first terminal device in the embodiments as shown in Figure 7 For example, when performing a sending operation, the transceiver 1430 can be regarded as a sender, and when performing a receiving operation, the transceiver 1430 can be regarded as a receiver; or the transceiver 1430 can be a general term of two functional units, i.e., a sender and a receiver. The sender is configured to complete a sending operation, for example, the sender can be configured to perform all the sending operations performed by the first terminal device in the embodiments as shown in Figure 7 For example, the receiver is configured to complete a receiving operation, for example, the receiver can be configured to perform all the receiving operations performed by the first terminal device in the embodiments as shown in Figure 7 For example, the receiver is configured to complete a receiving operation, for example, the receiver can be configured to perform all the receiving operations performed by the first terminal device in the embodiments as shown in

[0538] It should be understood that the first terminal device 1300 or the first terminal device 1400 according to the embodiments of the present application can implement Figure 7The functions of the first terminal device in the illustrated embodiments, and the operations and / or functions of the individual modules in the first terminal device 1300 or the first terminal device 1400, are respectively implemented in order to achieve Figure 7 The corresponding procedures in the illustrated embodiments are not described herein again in detail for brevity.

[0539] Figure 15 A schematic block diagram of a communication device 1500 is provided for embodiments of the present application. The communication device 1500 is exemplarily a first terminal device 1500.

[0540] The first terminal device 1500 includes a processing module 1510 and a transceiver module 1520. The first terminal device 1500 can be a terminal device, or a chip applied in a terminal device or other combination device, component, etc. having the functions of the terminal device described above. When the first terminal device 1500 is a terminal device, the transceiver module 1520 can be a transceiver, which can include an antenna and a radio frequency circuit, etc., and the processing module 1510 can be a processor, e.g., a baseband processor, which can include one or more central processing units (CPUs). When the first terminal device 1500 is a component having the functions of the terminal device described above, the transceiver module 1520 can be a radio frequency unit, and the processing module 1510 can be a processor, e.g., a baseband processor. When the first terminal device 1500 is a chip system, the transceiver module 1520 can be an input / output interface of the chip system (e.g., a baseband chip), and the processing module can be a processor of the chip system, which can include one or more central processing units.

[0541] The processing module 1510 can be configured to perform Figure 8 All operations performed by the first terminal device in the illustrated embodiments other than the transceiving operations, e.g., S81 and S82, and / or other processes for supporting the techniques described herein. The transceiver module 1520 can be configured to perform Figure 8 All transceiving operations performed by the first terminal device in the illustrated embodiments, e.g., the operation of receiving the first signal from the second terminal device, and / or other processes for supporting the techniques described herein.

[0542] In addition, the transceiver module 1520 can be a functional module that can complete both the sending operation and the receiving operation, e.g., the transceiver module 1520 can be configured to perform Figure 8All the transmitting operations and receiving operations performed by the first terminal device in the embodiments shown, for example, when performing a transmitting operation, the transceiver module 1520 can be considered as a transmitting module, and when performing a receiving operation, the transceiver module 1520 can be considered as a receiving module; or the transceiver module 1520 can also be a general term of two functional modules, i.e. a transmitting module and a receiving module, the transmitting module is used to complete a transmitting operation, for example, the transmitting module can be used to perform Figure 8 All the transmitting operations performed by the first terminal device in the embodiments shown, the receiving module is used to complete a receiving operation, for example, the receiving module can be used to perform Figure 8 All the receiving operations performed by the first terminal device in the embodiments shown.

[0543] For example, the processing module 1510 is configured to update a counter according to a demodulation result of a first signal from a second terminal device, wherein an initial value of the counter is greater than 0.

[0544] The processing module 1510 is further configured to determine whether a link between the first terminal device and the second terminal device fails according to a value of the counter.

[0545] As an optional implementation, the first signal is a control signal, and the processing module 1510 is configured to update the counter according to the demodulation result of the first signal from the second terminal device in the following manner:

[0546] If the first signal is successfully demodulated, the value of the counter is increased by a first value; or

[0547] If the first signal is missed, the value of the counter is decreased by a second value.

[0548] As an optional implementation, the first signal is a data signal, and the first signal is initial transmission data, and the processing module 1510 is configured to update the counter according to the demodulation result of the first signal from the second terminal device in the following manner:

[0549] If the first signal is successfully demodulated, the value of the counter is increased by a third value; or

[0550] If the first signal is unsuccessfully demodulated, the value of the counter is decreased by a fourth value.

[0551] As an optional implementation, the first signal is a data signal, and the first signal is retransmission data, and the processing module 1510 is configured to update the counter according to the demodulation result of the first signal from the second terminal device in the following manner:

[0552] If the first signal is successfully demodulated, the value of the counter is increased by a fifth value; or

[0553] decreases the value of the counter by a sixth value.

[0554] As an optional implementation, the processing module 1510 is configured to determine whether the link with the second terminal device fails according to the value of the counter by: when the value of the counter is 0, determining that the link fails.

[0555] It should be understood that the processing module 1510 in the embodiments of the present application can be implemented by a processor or a processor-related circuit component, and the transceiver module 1520 can be implemented by a transceiver or a transceiver-related circuit component.

[0556] As shown in Figure 16 The embodiments of the present application also provide a communication device 1600. The communication device 1600 is, for example, a first terminal device 1600. The first terminal device 1600 can be a communication device, for example, a terminal device, or can also be a chip system, etc. The first terminal device 1600 comprises a processor 1610, a memory 1620 and a transceiver 1630, wherein the memory 1620 stores instructions or programs, and the processor 1610 is configured to execute the instructions or programs stored in the memory 1620. When the instructions or programs stored in the memory 1620 are executed, the processor 1610 is configured to perform the operations performed by the processing module 1510 in the above embodiments, and the transceiver 1630 is configured to perform the operations performed by the transceiver module 1520 in the above embodiments.

[0557] The transceiver 1630 can be a functional unit that can complete both sending operations and receiving operations. For example, the transceiver 1630 can be configured to perform all the sending operations and receiving operations performed by the first terminal device in the embodiments shown in Figure 8 For example, when performing a sending operation, the transceiver 1630 can be regarded as a transmitter, and when performing a receiving operation, the transceiver 1630 can be regarded as a receiver; or the transceiver 1630 can also be a general term for two functional units, i.e., a transmitter and a receiver. The transmitter is configured to complete a sending operation, for example, the transmitter can be configured to perform all the sending operations performed by the first terminal device in the embodiments shown in Figure 8 For example, the receiver is configured to complete a receiving operation, for example, the receiver can be configured to perform all the receiving operations performed by the first terminal device in the embodiments shown in Figure 8 For example, the receiver is configured to complete a receiving operation, for example, the receiver can be configured to perform all the receiving operations performed by the first terminal device in the embodiments shown in

[0558] It should be understood that the first terminal device 1500 or the first terminal device 1600 according to the embodiments of the present application can implement Figure 8The functions of the first terminal device in the illustrated embodiments, and the operations and / or functions of the individual modules in the first terminal device 1500 or the first terminal device 1600, are respectively implemented in order to achieve Figure 8 The corresponding procedures in the illustrated embodiments are not described herein again in detail for brevity.

[0559] Figure 17 A schematic block diagram of a communication device 1700 is provided for embodiments of the present application. The communication device 1700 is exemplarily a first terminal device 1700.

[0560] The first terminal device 1700 includes a processing module 1710 and a transceiver module 1720. The first terminal device 1700 can be a terminal device, or a chip applied in a terminal device or other combination device, component, etc. having the functions of the terminal device described above. When the first terminal device 1700 is a terminal device, the transceiver module 1720 can be a transceiver, which can include an antenna and a radio frequency circuit, etc., and the processing module 1710 can be a processor, e.g., a baseband processor, which can include one or more central processing units (CPUs). When the first terminal device 1700 is a component having the functions of the terminal device described above, the transceiver module 1720 can be a radio frequency unit, and the processing module 1710 can be a processor, e.g., a baseband processor. When the first terminal device 1700 is a chip system, the transceiver module 1720 can be an input / output interface of the chip system (e.g., a baseband chip), and the processing module can be a processor of the chip system, which can include one or more central processing units.

[0561] The processing module 1710 can be configured to perform Figure 9 All operations performed by the first terminal device in the illustrated embodiments other than the transceiving operations, e.g., S91 and S92, and / or other processes for supporting the technologies described herein. The transceiver module 1720 can be configured to perform Figure 9 All transceiving operations performed by the first terminal device in the illustrated embodiments, e.g., operations of receiving signals from the second terminal device, and / or other processes for supporting the technologies described herein.

[0562] In addition, the transceiver module 1720 can be a functional module that can complete both the sending operation and the receiving operation, e.g., the transceiver module 1720 can be configured to perform Figure 9All the transmitting operations and receiving operations performed by the first terminal device in the embodiments shown, for example, when performing a transmitting operation, the transceiver module 1720 can be considered as a transmitting module, and when performing a receiving operation, the transceiver module 1720 can be considered as a receiving module; or the transceiver module 1720 can also be a general term of two functional modules, which are a transmitting module and a receiving module respectively, the transmitting module is used to complete a transmitting operation, for example, the transmitting module can be used to perform Figure 9 All the transmitting operations performed by the first terminal device in the embodiments shown, the receiving module is used to complete a receiving operation, for example, the receiving module can be used to perform Figure 9 All the receiving operations performed by the first terminal device in the embodiments shown.

[0563] For example, the processing module 1710 is configured to obtain a channel busy ratio in a second time length according to a number of first type channels and a total number of channels between the second terminal device, the first type channels include channels with a signal strength greater than or equal to a first threshold in the second time length.

[0564] The processing module 1710 is further configured to perform synchronization evaluation or out-of-sync evaluation on a link between the first terminal device 1700 and the second terminal device according to the channel busy ratio.

[0565] As an optional implementation, the processing module 1710 is configured to perform synchronization evaluation or out-of-sync evaluation on the link between the first terminal device 1700 and the second terminal device according to the channel busy ratio in the following manner:

[0566] When the channel busy ratio is greater than or equal to a second threshold, it is determined that the link is out-of-sync; or,

[0567] When the channel busy ratio is less than or equal to a third threshold, it is determined that the link is in-sync.

[0568] It should be understood that the processing module 1710 in the embodiments of the present application can be realized by a processor or a processor related circuit component, and the transceiver module 1720 can be realized by a transceiver or a transceiver related circuit component.

[0569] As Figure 18As shown, the embodiments of the present application further provide a communication apparatus 1800. Exemplarily, the communication apparatus 1800 is, for example, a first terminal apparatus 1800. Exemplarily, the first terminal apparatus 1800 can be a communication device, for example, a terminal device, or can also be a chip system, etc. The first terminal apparatus 1800 comprises a processor 1810, a memory 1820 and a transceiver 1830, wherein the memory 1820 stores instructions or programs, and the processor 1810 is configured to execute the instructions or programs stored in the memory 1820. When the instructions or programs stored in the memory 1820 are executed, the processor 1810 is configured to perform the operations performed by the processing module 1710 in the above-described embodiments, and the transceiver 1830 is configured to perform the operations performed by the transceiving module 1720 in the above-described embodiments.

[0570] Wherein, the transceiver 1830 can be a functional unit which can complete both sending operation and receiving operation. For example, the transceiver 1830 can be configured to perform the operations performed by the sending module 1712 in the above-described embodiments. Figure 9 Exemplarily, in the embodiments shown, all the sending operations and receiving operations performed by the first terminal apparatus, for example, when performing the sending operation, the transceiver 1830 can be considered as a sender, and when performing the receiving operation, the transceiver 1830 can be considered as a receiver; or the transceiver 1830 can also be a general term of two functional units, i.e. a sender and a receiver, the sender is configured to complete the sending operation, for example, the sender can be configured to perform the operations performed by the sending module 1712 in the above-described embodiments. Figure 9 Exemplarily, in the embodiments shown, all the sending operations performed by the first terminal apparatus, the receiver is configured to complete the receiving operation, for example, the receiver can be configured to perform the operations performed by the receiving module 1714 in the above-described embodiments. Figure 9 Exemplarily, in the embodiments shown, all the receiving operations performed by the first terminal apparatus.

[0571] It should be understood that the first terminal apparatus 1700 or the first terminal apparatus 1800 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown, and the operations and / or functions of each module in the first terminal apparatus 1700 or the first terminal apparatus 1800 are respectively to realize the corresponding flow in the embodiments shown, which will not be described herein again for the sake of brevity. Figure 9 It should be understood that the first terminal apparatus 1700 or the first terminal apparatus 1800 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown, and the operations and / or functions of each module in the first terminal apparatus 1700 or the first terminal apparatus 1800 are respectively to realize the corresponding flow in the embodiments shown, which will not be described herein again for the sake of brevity. Figure 9 It should be understood that the first terminal apparatus 1700 or the first terminal apparatus 1800 according to the embodiments of the present application can realize the functions of the first terminal apparatus in the embodiments shown, and the operations and / or functions of each module in the first terminal apparatus 1700 or the first terminal apparatus 1800 are respectively to realize the corresponding flow in the embodiments shown, which will not be described herein again for the sake of brevity.

[0572] Figure 19 A schematic block diagram of a communication apparatus 1900 according to an embodiment of the present application is shown. Exemplarily, the communication apparatus 1900 is, for example, a second terminal apparatus 1900.

[0573] The second terminal device 1900 includes a processing module 1910 and a transceiver module 1920. Exemplarily, the second terminal device 1900 may be a terminal device, or a chip used in a terminal device, or other combined device or component having the aforementioned terminal device functions. When the second terminal device 1900 is a terminal device, the transceiver module 1920 may be a transceiver, which may include an antenna and a radio frequency circuit, etc., and the processing module 1910 may be a processor, such as a baseband processor, which may include one or more CPUs. When the second terminal device 1900 is a component having the aforementioned terminal functions, the transceiver module 1920 may be a radio frequency unit, and the processing module 1910 may be a processor, such as a baseband processor. When the second terminal device 1900 is a system-on-chip (SoC), the transceiver module 1920 may be the input / output interface of the SoC (e.g., a baseband chip), and the processing module may be the SoC's processor, which may include one or more central processing units.

[0574] The processing module 1910 can be used to execute Figure 10 In the embodiment shown, all operations except the transceiver operations performed by the second terminal device, such as S102 and S103, and / or other processes for supporting the technology described herein. The transceiver module 1920 may be used to perform Figure 10 All transceiver operations performed by the second terminal device in the illustrated embodiment, such as S101 , and / or other processes for supporting the technology described herein.

[0575] In addition, the transceiver module 1920 may be a functional module that can perform both sending and receiving operations. For example, the transceiver module 1920 may be used to perform Figure 10 In the embodiment shown, all sending operations and receiving operations performed by the second terminal device, for example, when performing a sending operation, the transceiver module 1920 can be considered as a sending module, and when performing a receiving operation, the transceiver module 1920 can be considered as a receiving module; or, the transceiver module 1920 can also be a general term for two functional modules, which are a sending module and a receiving module. The sending module is used to complete the sending operation, for example, the sending module can be used to perform Figure 10 In the embodiment shown, all sending operations are performed by the second terminal device, and the receiving module is used to complete the receiving operation. For example, the receiving module can be used to ...

Claims

1. A link evaluation method, characterized in that: include: The first terminal device obtains a channel busy rate within a second time period based on the number of first-category channels and the total number of channels between the first terminal device and the second terminal device, wherein the first-category channels include channels whose signal strength is greater than or equal to a first threshold within the second time period; The first terminal device performs synchronization evaluation or out-of-synchronization evaluation on the link between the first terminal device and the second terminal device according to the channel busy rate; The step of performing, by the first terminal device, a synchronization assessment or a desynchronization assessment on a link between the first terminal device and the second terminal device according to the channel busy rate includes: When the channel busy rate is greater than or equal to a second threshold, the first terminal device determines that the link is out of sync; or when the channel busy rate is less than or equal to a third threshold, the first terminal device determines that the link is in sync.

2. The method according to claim 1, characterized in that The method further comprises: The physical layer of the first terminal device determines that the link is out of synchronization, and sends a link out of synchronization indication to a higher layer of the first terminal device; or The physical layer of the first terminal device determines the link synchronization and sends a link synchronization indication to the upper layer of the first terminal device.

3. The method according to claim 2, characterized in that The method further comprises: A higher layer of the first terminal device determines whether the link fails according to the link synchronization indication or the link desynchronization indication.

4. The method according to any one of claims 1 to 3, characterized in that The method further comprises: The physical layer of the first terminal device sends validity information of the first evaluation information to the upper layer of the first terminal device, the validity information indicating that the validity of the first evaluation information is low or that the first evaluation information is invalid; or The physical layer of the first terminal device sends second evaluation information to a higher layer of the first terminal device without sending the first evaluation information, where the second evaluation information includes a link synchronization indication or a link out-of-sync indication, where the link synchronization indication or the link out-of-sync indication is determined based on the channel busy rate; The first evaluation information includes synchronization indication information or out-of-sync indication information of the link, and the synchronization indication information or the out-of-sync indication information is obtained based on at least one target reference signal in at least one reference period, and the at least one target reference signal is transmitted non-periodically.

5. The method according to claim 4, characterized in that The method further comprises: The first terminal device receives at least one reference signal from a second terminal device within a first reference period, wherein the at least one reference signal is transmitted aperiodically; Determining, by the first terminal device, a first target reference signal in the first reference period based on the at least one reference signal; The first terminal device obtains the synchronization indication information or the out-of-sync indication information of the link based on the at least one target reference signal in the at least one reference cycle, the at least one reference cycle includes the first reference cycle, and the at least one target reference signal includes the first target reference signal.

6. The method according to claim 5, characterized in that The first terminal device determining, based on the at least one reference signal, a first target reference signal within the first reference period, comprising: The first terminal device determines one of the at least one reference signal as the first target reference signal; or The first terminal device combines part or all of the at least one reference signal to obtain the first target reference signal.

7. The method according to claim 5 or 6, characterized in that The first terminal device determining, based on the at least one reference signal, a first target reference signal within the first reference period, comprising: In a case where the cumulative density of first N reference signals in the at least one reference signal is greater than or equal to a reference density, the first terminal device uses the first N reference signals as the first target reference signals, where N is greater than or equal to 1, wherein the density of a reference signal is the number of frequency domain elements that carry the reference signal in a bandwidth occupied by one reference signal, and the cumulative density of the reference signal is the sum of the densities of one or more reference signals; or When the accumulated bandwidth of first N reference signals in the at least one reference signal is greater than or equal to the reference bandwidth, the first terminal device uses the first N reference signals as the first target reference signals, where N is greater than or equal to 1.

8. The method according to claim 4, characterized in that The method further comprises: The first terminal device determines the duration of the reference period; or, The first terminal device receives first indication information from the second terminal device, where the first indication information is used to indicate a duration of the reference cycle.

9. The method according to claim 8, characterized in that The first terminal device determines the duration of the reference period, including: The first terminal device determines the duration of the reference cycle based on the parameters of the data packet of the first service, where the data packet of the first service is transmitted through the link, and the parameters of the data packet of the first service include the expected cycle duration of the data packet of the first service, and / or the retransmission configuration information of the data packet of the first service.

10. The method according to claim 9, characterized in that The duration of the reference period satisfies: T=min(first threshold,ceil(T packet ×P1)); Wherein, T represents the duration of the reference period, the first threshold is a constant, and T packet represents the minimum expected cycle duration of the data packet of the first service, P1 represents the retransmission configuration information of the first service, and ceil() represents the rounding-up operation.

11. The method according to claim 4, characterized in that The first terminal device obtaining the synchronization indication information or the out-of-synchronization indication information of the link according to the at least one target reference signal in the at least one reference period includes: The first terminal device obtains synchronization indication information or out-of-sync indication information of the link based on at least one target reference signal in the at least one reference period included in the first time length, and the at least one reference period is at least one reference period in which a reference signal is received among all reference periods in the first time length.

12. The method according to claim 11, characterized in that The method further comprises: The first terminal device determines the first duration according to the duration of the reference period; or, The first terminal device receives second indication information from the second terminal device, where the second indication information is used to indicate the first duration.

13. The method according to claim 12, characterized in that The first terminal device obtains the synchronization indication information of the link according to the at least one target reference signal in the at least one reference period included in the first duration; The first terminal device determines the first duration according to the duration of the reference period, including: The first terminal device determines that the first duration satisfies: L in =max(100,M in ×T), L in Indicates the first duration, M in represents the number of periodic reference signals participating in the synchronization measurement within the first duration when the synchronization measurement of the link is performed according to the periodic reference signal, and T represents the duration of the reference period; or The first terminal device obtains, according to the at least one target reference signal in the at least one reference period included in the first duration, out-of-synchronization indication information of the link; and the first terminal device determines the first duration according to the duration of the reference period, including: The first terminal device determines that the first duration satisfies: L out =max(200,M out ×T), L out Indicates the first duration, M out represents the number of periodic reference signals participating in the out-of-sync measurement within the first duration when out-of-sync measurement is performed on the link according to the periodic reference signal, and T represents the duration of the reference period.

14. The method according to claim 12, characterized in that The first terminal device determines the first duration according to the duration of the reference period, including: The first terminal device determines the first duration based on the duration of the reference period and a first parameter, where the first parameter includes a reference density and / or a reference bandwidth, the reference density is used to determine the target reference signal, and the reference bandwidth is used to determine the target reference signal.

15. The method according to claim 14, characterized in that The first terminal device determines the first duration according to the reference period and a parameter related to the reference density, including: The first duration is used to obtain the synchronization indication information, and the first duration satisfies the following formula: L in =max(second threshold,ceil(M in ×P2)×T),L in represents the first duration, T represents the duration of the reference period, M in represents the number of reference signals participating in the synchronization measurement within the first duration when the synchronization measurement is performed on the link according to the periodic reference signal, and P2 represents a parameter related to the reference density; or The first duration is used to obtain the out-of-sync indication information, and the first duration satisfies the following formula: L out =max(second threshold,ceil(M out ×P2)×T),L out represents the first duration, T represents the duration of the reference period, M out represents the number of reference signals participating in the out-of-sync measurement within the first duration when out-of-sync measurement is performed on the link according to the periodic reference signal, and P2 represents a parameter related to the reference density; Among them, ceil() represents the rounding up operation.

16. The method according to claim 14, characterized in that The first terminal device determines the first duration according to the reference period and parameters related to the reference bandwidth, including: The first duration is used to obtain the synchronization indication information, and the first duration satisfies the following formula: L in =max(second threshold,ceil(M in ×P3)×T),L in represents the first duration, T represents the reference period, M in represents the number of reference signals participating in the synchronization measurement within the first duration when the synchronization measurement is performed on the link according to the periodic reference signal, and P3 represents a parameter related to the reference bandwidth; or The first duration is used to obtain the out-of-sync indication information, and the first duration satisfies the following formula: L out =max(second threshold,ceil(M out ×P3)×T),L out represents the first duration, T represents the reference period, M out represents the number of reference signals participating in the synchronization measurement within the first duration when the synchronization measurement of the link is performed according to the periodic reference signal, and P3 represents a parameter related to the reference bandwidth; Among them, ceil() represents the rounding up operation.

17. The method according to claim 14, characterized in that The first terminal device determines the first duration according to the reference period, transmission related to the reference density, and parameters related to the reference bandwidth, including: The first duration is used to obtain the synchronization indication information, and the first duration satisfies the following formula: L in =max(second threshold,ceil(M in ×P2×P3)×T)L in represents the first duration, T represents the reference period, M in represents the number of reference signals participating in the synchronization measurement within the first duration when the synchronization measurement of the link is performed according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth; or, The first duration is used to obtain the out-of-sync indication information, and the first duration satisfies the following formula: L in =max(second threshold,ceil(M out ×P2×P3)×T)L in represents the first duration, T represents the reference period, M out represents the number of reference signals participating in synchronization measurement within the first duration when out-of-sync measurement is performed on the link according to the periodic reference signal, P2 represents a parameter related to the reference density, and P3 represents a parameter related to the reference bandwidth; Among them, ceil() represents the rounding up operation.

18. The method according to claim 4, characterized in that The method further comprises: The first terminal device determines validity information, where the validity information is used to indicate the validity of the synchronization indication information or the validity of the out-of-sync indication information, wherein a greater number of the at least one reference cycle indicates a higher validity of the synchronization indication information or the out-of-sync indication information.

19. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is run on a computer, the computer is caused to execute the method according to any one of claims 1 to 18.

20. A communication device, characterized in that: The communication device comprises: a memory for storing instructions; At least one processor is configured to call and execute the instructions from the memory, so that the communication device implements the method according to any one of claims 1 to 18.

21. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is run on a computer, the computer is caused to perform the method according to any one of claims 1 to 18.

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