Communication method and system, and related apparatus

Abstract

The present application provides a communication method and system, and a related apparatus. In the method, a terminal can perform reverse calculation on an uplink channel on the basis of first downlink CSI to obtain channel state information, i.e., first uplink CSI, of the uplink channel. In the present application, it is not necessary to measure the uplink channel by means of a method of performing interaction on an uplink reference signal by means of the terminal and a network device; instead, reverse calculation is performed on the uplink channel on the basis of a reciprocity calibration result of radio frequency channels of the terminal to measure the uplink channel, so as to obtain the first uplink CSI. Therefore, signaling interactions can be reduced, and the measurement efficiency for the uplink channel can also be improved.

Description

Communication method, system and related device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 29, 2023, with application number 202311627134.1 and application name “Communication Methods, Systems and Related Devices”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of communication technology, and in particular, to a communication method, system, and related devices. Background Art

[0003] The transmission quality of a network is closely related to the channel quality. Channel measurement can be performed before information is transmitted on a channel to determine the channel quality. For a channel between a network device and a terminal, the network device can use this channel to send downlink information to the terminal, and the terminal can use this channel to send uplink information to the network device. The channel used to carry downlink information can be used as a downlink channel, and the channel used to carry uplink information can be used as an uplink channel.

[0004] Currently, network equipment can send reference signals to terminals. Terminals use the reference signals to measure downlink channels, obtain channel state information (CSI) for the downlink channels, and feed it back to the network equipment. Similarly, terminals can send reference signals to network equipment. The network equipment uses the reference signals to measure uplink channels and obtain uplink CSI. Currently, the signaling overhead for network equipment to determine downlink and uplink CSI is high. Summary of the Invention

[0005] Embodiments of the present application provide a communication method, system, and related apparatus. A terminal measures a downlink channel to obtain downlink CSI, and can obtain uplink CSI by performing reciprocity compensation for the downlink CSI. The terminal can report the downlink CSI and uplink CSI to a network device, thereby saving signaling overhead.

[0006] In a first aspect, a communication method is provided. This method can be performed by a communication device, which can be a terminal, or a component configured in a terminal (such as a chip, a chip system, a processor, etc.), or a logic module or software capable of implementing all or part of the functions of the communication device. For ease of understanding and explanation, the method is described below using a terminal as an example.

[0007] Exemplarily, the method includes: the terminal receives a first reference signal and sends first uplink channel state information, wherein the first uplink channel state information is obtained by performing RF channel reciprocity compensation on the first downlink channel state information, and the first downlink channel state information is obtained based on the first reference signal.

[0008] Among them, the first reference signal is a downlink reference signal, and the downlink reference signal comes from a network device. Exemplarily, the first reference signal can be sent by the network device to the terminal, or the first reference signal is broadcast by the network device. The first downlink reference signal is used to measure the downlink channel between the network device and the terminal. In this application, the terminal receives the first reference signal and can measure the downlink channel to obtain downlink channel state information (CSI). For the sake of distinction and explanation in this application, the downlink CSI obtained by the terminal based on the first reference signal can be referred to as the first downlink CSI. In other words, the first downlink CSI is obtained based on the first reference signal.

[0009] After obtaining the first downlink CSI, the terminal can perform RF channel reciprocity compensation on the first downlink CSI to obtain the first uplink CSI. The RF channel is the RF channel of the terminal. The terminal may include at least two antennas, and each antenna may correspond to a RF channel. The RF channel corresponding to each antenna can be understood as the RF channel connected to the antenna. For example, the antenna receives a first reference signal and transmits it to the RF channel for processing. The RF channel can send a signal through the antenna. It can be said that the antenna corresponds to the RF channel.

[0010] In the present application, the terminal performs RF channel reciprocity compensation on the first downlink CSI, which can be understood as: the terminal performs compensation processing on the first downlink CSI according to the reciprocity calibration result of the terminal's RF channel, or, in other words, the terminal performs reverse calculation (or reciprocity compensation, or reverse compensation) on the first downlink CSI according to the reciprocity calibration result of the RF channel. In a possible scenario, the first downlink CSI can be expressed in matrix form, and the reciprocity calibration result of the RF channel can also be expressed in matrix form. The terminal performs RF channel reciprocity compensation on the first downlink CSI, which can be understood as: the terminal calculates the reciprocity calibration result of the first downlink CSI and the RF channel, or, in other words, the terminal calculates two matrices.

[0011] The reciprocity calibration result of the RF channel may include: difference information between the RF channels corresponding to the first reference signal. The RF channel corresponding to the first reference signal can be understood as: the RF channel in the terminal that receives the first reference signal. For example, for example, the terminal includes antenna 1 and antenna 2, and both antenna 1 and antenna 2 receive the first reference signal. The RF channels corresponding to the first reference signal may include: the RF channel corresponding to antenna 1 and the RF channel corresponding to antenna 2.

[0012] In some embodiments, the difference information between radio frequency channels may include: the delay difference and / or phase difference between the radio frequency channels. It should be understood that the radio frequency channel may include a transmitting channel and a receiving channel. In one possible scenario, the delay difference and / or phase difference between the radio frequency channels may include: the delay difference and / or phase difference between the transmitting channels corresponding to each antenna, and the delay difference and / or phase difference between the receiving channels corresponding to each antenna of the terminal. It should be understood that the transmitting channel corresponding to each antenna can be understood as: the transmitting channel in the radio frequency channel corresponding to each antenna. The receiving channel corresponding to each antenna can be understood as: the receiving channel in the radio frequency channel corresponding to each antenna.

[0013] The time delay difference and / or phase difference between radio frequency channels may be understood as the time delay difference and / or phase difference between the radio frequency channels of other antennas and the radio frequency channel of the reference antenna.

[0014] For example, taking the case where the terminal includes antenna 1 and antenna 2, and antenna 1 as the reference signal, the time delay difference and / or phase difference between the radio frequency channels can be understood as: the time delay difference and / or phase difference between the radio frequency channel corresponding to antenna 2 and the radio frequency channel corresponding to antenna 1. The time delay difference and / or phase difference between the transmitting channels corresponding to each antenna may include: the time delay difference and / or phase difference between the transmitting channel corresponding to antenna 1 and the transmitting channel corresponding to antenna 2. The time delay difference and / or phase difference between the receiving channels corresponding to each antenna may include: the time delay difference and / or phase difference between the receiving channel corresponding to antenna 1 and the receiving channel corresponding to antenna 2.

[0015] Exemplarily, taking the case where the terminal includes antenna 1, antenna 2, and antenna 3, the reference antenna may be antenna 1, antenna 2, or antenna 3. Taking antenna 1 as the reference antenna, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the RF channel corresponding to antenna 2 and the RF channel corresponding to antenna 1, and the delay difference and / or phase difference between the RF channel corresponding to antenna 3 and the RF channel corresponding to antenna 1. Specifically, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the receiving channel corresponding to antenna 2 and the receiving channel corresponding to antenna 1, and the delay difference and / or phase difference between the receiving channel corresponding to antenna 3 and the receiving channel corresponding to antenna 1, and the delay difference and / or phase difference between the transmitting channel corresponding to antenna 2 and the transmitting channel corresponding to antenna 1, and the delay difference and / or phase difference between the transmitting channel corresponding to antenna 3 and the transmitting channel corresponding to antenna 1.

[0016] In some embodiments, because the first uplink CSI is calculated from the first downlink CSI and difference information between RF channels, the difference information between RF channels may include: delay difference and / or phase difference between RF channels. Therefore, it can be said that the first uplink channel state information is associated with the difference information between RF channels corresponding to the first reference signal, and the difference information includes the delay difference and / or phase difference.

[0017] In an embodiment of the present application, the terminal performs reciprocity calibration on the radio frequency channel, which can enable reciprocity of the uplink and downlink channels between the network device and the terminal. In this way, the terminal can perform reverse calculation of the uplink channel based on the first downlink CSI to obtain the channel state information of the uplink channel, that is, the first uplink CSI. In the present application, there is no need to use a method of exchanging uplink reference signals between the terminal and the network device to achieve measurement of the uplink channel. Instead, based on the reciprocity calibration result of the terminal's radio frequency channel, the uplink channel is reversely calculated to achieve measurement of the uplink channel and obtain the first uplink CSI. This can reduce signaling interaction and improve the measurement efficiency of the uplink channel.

[0018] In addition, when there are multiple terminals interacting with the network device, the network device does not need to pre-allocate resources for sending uplink reference signals to each terminal, or the terminals do not need to take turns sending uplink reference signals to the network device, which can save channel air interface resources.

[0019] In the embodiment of the present application, after obtaining the first downlink CSI and the first uplink CSI, the terminal can send the first downlink CSI and the first uplink CSI to the network device. In this way, the network device can obtain the first downlink CSI and the first uplink CSI without having to measure the uplink channel based on the uplink reference signal from the terminal, thereby improving the measurement efficiency of the uplink channel. In other words, the terminal carries the first uplink CSI when sending the first downlink CSI to the network device.

[0020] In one possible implementation, the first downlink channel state information (CSI) and the first uplink channel state information (CSI) are carried in the same message. For example, currently in a WLAN system, after a terminal measures a downlink channel based on a first reference signal, the first downlink CSI may be encapsulated in a compressed beamforming report. In an embodiment of the present application, after obtaining the first downlink CSI and the first uplink CSI, the terminal may encapsulate the first downlink CSI and the first uplink CSI in a compressed beamforming report, and the terminal may send the compressed beamforming report to a network device.

[0021] In one possible implementation, the first downlink CSI and the first uplink CSI may be carried in different messages. Exemplarily, the terminal may first send the first downlink CSI to the network device, and then send the first uplink CSI to the network device. For example, when the first downlink CSI is calculated, the terminal may first send the first downlink CSI to the network device, and when the terminal obtains the first uplink CSI by reversely calculating the first downlink CSI, the terminal may send the first uplink CSI to the network device. Alternatively, after obtaining the first downlink CSI and the first uplink CSI, the terminal may first send the first downlink CSI to the network device, and then send the first uplink CSI to the network device. This embodiment of the present application does not limit this. In a WLAN system, the terminal may carry the first downlink CSI in a compressed beamforming report and send the compressed beamforming report to the network device. After sending the compressed beamforming report, the terminal may send a message carrying the first uplink CSI to the network device.

[0022] In conjunction with the first aspect, in certain possible implementations of the first aspect, before sending the first reference signal to the terminal, the network device may further send first information to the terminal, or the network device may broadcast the first information. Accordingly, the terminal may receive the first information. The first information is used to indicate reporting of downlink channel state information and uplink channel state information.

[0023] It should be understood that in current communication protocols, a network device can send an instruction to a terminal, instructing the terminal to report downlink channel state information. In this example, the terminal can measure the downlink channel, obtain only the downlink CSI, and report the downlink CSI to the network device, without reporting both the downlink CSI and the uplink CSI to the network device.

[0024] Alternatively, the network device may send an instruction to the terminal, instructing the terminal to send an uplink reference signal. In this example, the terminal may send an uplink reference signal to the network device, which measures the uplink channel and obtains only uplink CSI. The terminal does not need to report the uplink CSI.

[0025] In an embodiment of the present application, a network device may transmit first information, and accordingly, a terminal may receive the first information. In other words, the network device may instruct the terminal to report downlink CSI and uplink CSI. Thus, after obtaining the first downlink CSI based on the first reference signal, the terminal may perform reciprocity compensation on the first downlink CSI based on the reciprocity calibration result of the terminal's radio frequency channel to obtain the first uplink CSI. The terminal may obtain both the first downlink CSI and the first uplink CSI. This reduces signaling interaction and improves uplink channel measurement efficiency.

[0026] In conjunction with the first aspect, in certain possible implementations of the first aspect, the terminal may send second information, where the second information is used to indicate that the terminal has the ability to report downlink channel state information and uplink channel state information. Accordingly, the network device may receive the second information, and based on the second information, the network device may determine that the terminal has the ability to report downlink channel state information and uplink channel state information. When the network device determines that the terminal has the ability to report downlink channel state information and uplink channel state information, the network device may send first information to the terminal, instructing the terminal to report the downlink channel state information and uplink channel state information.

[0027] In one possible scenario, in a WLAN system, the association request may include the second information. Alternatively, the association request may include information indicating the ability to report CSI and uplink CSI, and the association request may be considered the second information. In some embodiments, the terminal may also send the second information to the network device after associating with the network device.

[0028] In one possible scenario, in an LTE system, a terminal may send the second information to a network device during the process of establishing a connection with the network device. For example, based on current LTE protocol specifications, in some embodiments, the terminal may include the second information when reporting its capability information to the network device. Alternatively, the terminal may send the second information to the network device after establishing a connection with the network device.

[0029] The above example describes a method in which a terminal can perform reciprocity compensation for the first downlink CSI based on the reciprocity calibration result of the RF channel to obtain the first uplink CSI. The following describes a method in which a terminal obtains the reciprocity calibration result of the RF channel:

[0030] First, the terminal supports self-calibration, that is, the terminal can perform reciprocity calibration on the RF channel by itself to obtain the delay difference and / or phase difference between the RF channels of the terminal.

[0031] In which, the terminal traverses each antenna that receives the first reference signal, and the terminal can send the first signal through the transmission channel corresponding to one of the antennas that receives the first reference signal, and receive the first signal through the transmission channels corresponding to the remaining antennas that receive the first reference signal. After the terminal traverses each antenna that receives the first reference signal, the terminal can determine the delay difference and / or phase difference between the terminal's radio frequency channels based on the sent first signal and the received first signal.

[0032] For example, taking a terminal including antenna 1 and antenna 2 as an example, antenna 1 and antenna 2 both receive a first reference signal, that is, the first reference signal corresponds to antenna 1 and antenna 2, or in other words, the first reference signal corresponds to the radio frequency channel of antenna 1 and the radio frequency channel corresponding to antenna 2. In this example, the terminal transmits a first signal through the transmit channel of antenna 1, and the terminal receives the first signal through the receive channel of antenna 2. The terminal transmits a second signal through the transmit channel of antenna 2, and the terminal receives the second signal through the receive channel of antenna 1. The terminal can determine the delay difference and / or phase difference between the radio frequency channels of the terminal based on the transmitted first signal, the received first signal, the transmitted second signal, and the received second signal.

[0033] The first signal transmitted by the transmit channel corresponding to antenna 1 is received by the receive channel corresponding to antenna 2 through spatial transmission, thereby completing the measurement of the transmit channel corresponding to antenna 1 and the receive channel corresponding to antenna 2, and obtaining the time delay and phase of the receive channel corresponding to antenna 2, as well as the time delay and phase of the transmit channel corresponding to antenna 1. Similarly, the second signal transmitted by the transmit channel corresponding to antenna 2 is received by the receive channel corresponding to antenna 1 through spatial transmission, thereby completing the measurement of the transmit channel corresponding to antenna 2 and the receive channel corresponding to antenna 1, and obtaining the time delay and phase of the receive channel corresponding to antenna 1, as well as the time delay and phase of the transmit channel corresponding to antenna 2. The terminal can perform difference processing on the time delay and phase of the receive channel corresponding to antenna 2 and the time delay and phase of the receive channel corresponding to antenna 1, to obtain the time delay difference and / or phase difference between the receive channel corresponding to antenna 2 and the receive channel corresponding to antenna 1, and the time delay difference and / or phase difference between the transmit channel corresponding to antenna 2 and the transmit channel corresponding to antenna 1.

[0034] Second, the terminal does not support self-calibration, that is, the terminal itself does not have the ability to perform reciprocity calibration on the RF channel. In this example, the terminal can exchange reference signals with the network device to achieve reciprocity calibration of the RF channel by the terminal.

[0035] The terminal can proactively initiate a reciprocity calibration request for the radio frequency channel to the network device. For example, the terminal can send a second reference signal to the network device. The second reference signal is an uplink reference signal. Upon receiving the second reference signal, the network device can measure the uplink channel, obtain second uplink channel state information, and send the second uplink channel state information to the terminal. The second uplink channel state information can be obtained based on the second reference signal.

[0036] In addition, in response to receiving the second reference signal, the network device may send a third reference signal to the terminal, where the third reference signal is a downlink reference signal. The terminal may measure the downlink channel based on the third reference signal to obtain second downlink channel state information.

[0037] In this way, the terminal can obtain the second uplink channel state information and the second downlink channel state information, and the terminal can determine the delay difference and / or the phase difference based on the second uplink channel state information and the second downlink channel state information. In other words, the terminal performs reciprocity calibration on the terminal's radio frequency channel based on the second uplink channel state information and the second downlink channel state information to obtain the delay difference and / or the phase difference. For details, please refer to the relevant description in Figure 10 of the following embodiment.

[0038] On the second aspect, a communication method is provided. A communication method is provided, which can be executed by a communication device. The communication device can be a network device, or it can be a component configured in the network device (such as a chip, a chip system, a processor, etc.), or it can also be a logic module or software that can implement all or part of the functions of the communication device.

[0039] It should be understood that the method provided in the second aspect corresponds to that in the first aspect. For descriptions of the same or corresponding contents, please refer to the relevant descriptions in the first aspect and will not be repeated here.

[0040] Exemplarily, the network device may send a first reference signal and receive first uplink channel state information, where the first uplink channel state information is obtained by performing RF channel reciprocity compensation on the first downlink channel state information, and the first downlink channel state information is obtained based on the first reference signal.

[0041] In a possible implementation manner, the method further includes: the network device receiving the first downlink channel state information, where the first downlink channel state information and the first uplink channel state information are carried in the same message.

[0042] In a possible implementation, before sending the first reference signal, the method further includes: the network device sending first information, where the first information is used to instruct to report downlink channel state information and uplink channel state information.

[0043] In a possible implementation, the method further includes: the network device receiving second information, where the second information is used to indicate that the network device has the capability of reporting downlink channel state information and uplink channel state information.

[0044] In a possible implementation, the first uplink channel state information is associated with difference information between radio frequency channels corresponding to the first reference signal, and the difference information includes a delay difference and / or a phase difference.

[0045] In one possible implementation, the method further includes: the network device receiving a second reference signal, and sending second uplink channel state information, where the second uplink channel state information is obtained based on the second reference signal. Furthermore, the network device may send a third reference signal, where the third reference signal is used to determine second downlink channel state information, where the delay difference and / or phase difference is obtained based on the second uplink channel state information and the second downlink channel state information.

[0046] In a third aspect, the present application provides a communication device, comprising modules or units for implementing the method in the first aspect and any possible implementation of the first aspect. Each module or unit can implement the corresponding function by executing a computer program.

[0047] Exemplarily, the communication device in the third aspect is a terminal, or a component configured in a terminal, such as a chip, a chip system, a processor, etc.

[0048] In a fourth aspect, the present application provides a communication device, comprising a processor, wherein the processor is configured to execute the communication method described in the first aspect and any possible implementation manner of the first aspect.

[0049] Optionally, the apparatus further comprises a memory for storing instructions and data. The memory is coupled to the processor, and when the processor executes the instructions stored in the memory, the methods described in the above aspects can be implemented.

[0050] Optionally, the device further includes a communication interface, which is used for the device to communicate with other communication devices. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, pin or other types of communication interfaces.

[0051] Illustratively, the communication device provided in the fourth aspect is a chip or a chip system.

[0052] In a fifth aspect, the present application provides a communication device comprising a processor and a communication interface, wherein the communication interface is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device, wherein the processor implements the communication method described in the first aspect and any possible implementation of the first aspect through a logic circuit or by executing code instructions. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, pin, or other type of communication interface.

[0053] Optionally, the device further comprises a memory for storing instructions and data. The memory is coupled to the processor, and when the processor executes the instructions stored in the memory, the method described in the first aspect above can be implemented.

[0054] In a sixth aspect, the present application provides a communication device comprising a processor and a memory, wherein the memory is used to store instructions and data. When the processor executes the instructions stored in the memory, it can implement the communication method described in the first aspect and any possible implementation method of the first aspect.

[0055] Optionally, the device further includes a communication interface, which is used for the device to communicate with other communication devices. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, pin or other types of communication interfaces.

[0056] Exemplarily, the communication device in the fifth aspect or the sixth aspect is a terminal.

[0057] In a seventh aspect, the present application provides a communication device, comprising modules or units for implementing the method in the second aspect and any possible implementation of the second aspect. Each module or unit can implement the corresponding function by executing a computer program.

[0058] Exemplarily, the communication device in the third aspect is a terminal, or a component configured in a terminal, such as a chip, a chip system, a processor, etc.

[0059] In an eighth aspect, the present application provides a communication device, comprising a processor, wherein the processor is configured to execute the communication method described in the second aspect and any possible implementation manner of the second aspect.

[0060] Optionally, the apparatus further comprises a memory for storing instructions and data. The memory is coupled to the processor, and when the processor executes the instructions stored in the memory, the methods described in the above aspects can be implemented.

[0061] Optionally, the device further includes a communication interface, which is used for the device to communicate with other communication devices. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, pin or other types of communication interfaces.

[0062] Illustratively, the communication device provided in the eighth aspect is a chip or a chip system.

[0063] In a ninth aspect, the present application provides a communication device comprising a processor and a communication interface, wherein the communication interface is configured to receive a signal from a communication device other than the communication device and transmit the signal to the processor, or to send a signal from the processor to a communication device other than the communication device, wherein the processor implements the communication method described in the second aspect and any possible implementation of the second aspect through a logic circuit or by executing code instructions. Exemplarily, the communication interface may be a transceiver, a circuit, a bus, a module, a pin, or another type of communication interface.

[0064] Optionally, the device further comprises a memory for storing instructions and data. The memory is coupled to the processor, and when the processor executes the instructions stored in the memory, the method described in the second aspect above can be implemented.

[0065] In the tenth aspect, the present application provides a communication device comprising a processor and a memory, wherein the memory is used to store instructions and data. When the processor executes the instructions stored in the memory, it can implement the communication method described in the above-mentioned second aspect and any possible implementation method of the second aspect.

[0066] Optionally, the device further includes a communication interface, which is used for the device to communicate with other communication devices. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, pin or other types of communication interfaces.

[0067] Exemplarily, the communication device in the ninth aspect or the tenth aspect is a network device.

[0068] In an eleventh aspect, the present application provides a computer-readable storage medium comprising a computer program, which, when executed on a computer, enables the computer to implement the method in the first or second aspect and any possible implementation of the first or second aspect.

[0069] In the twelfth aspect, the present application provides a computer program product, which includes: a computer program (also referred to as code, or instructions), which, when run, enables the computer to execute the method in the first or second aspect and any possible implementation of the first or second aspect.

[0070] In a thirteenth aspect, a communication system is provided, comprising the aforementioned terminal and network device.

[0071] The third to thirteenth aspects of this application correspond to the technical solutions of the first and second aspects of this application. The beneficial effects achieved by each aspect and the corresponding feasible implementation methods are similar and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] FIG1 is a schematic diagram of the architecture of a communication system applicable to the communication method provided in this application;

[0073] FIG2 is a communication diagram of a network device and a terminal applicable to the communication method provided by the present application;

[0074] FIG3A is a schematic diagram of a downlink channel measurement process in an LTE system;

[0075] FIG3B is a schematic diagram of resource allocation for network devices;

[0076] FIG4 is a timing diagram of downlink channel measurement in a WLAN system;

[0077] FIG5 is a schematic diagram of a channel between a network device and a terminal according to an embodiment of the present application;

[0078] FIG6 is a schematic flow chart of a communication method provided in an embodiment of the present application;

[0079] FIG7 is a timing diagram of a communication method provided in an embodiment of the present application;

[0080] FIG8 is another schematic flow chart of a communication method provided in an embodiment of the present application;

[0081] FIG9 is a schematic flowchart of a terminal performing reciprocity calibration on a radio frequency channel according to an embodiment of the present application;

[0082] FIG10 is another schematic flowchart of a terminal performing reciprocity calibration on a radio frequency channel according to an embodiment of the present application;

[0083] FIG11 is a schematic diagram showing the linear relationship between the phase difference and frequency between the RF channels of the terminal;

[0084] FIG12 is another timing diagram of the communication method provided in an embodiment of the present application;

[0085] FIG13 is a schematic structural diagram of a measuring device provided in an embodiment of the present application;

[0086] FIG14 is another schematic structural diagram of a measuring device provided in an embodiment of the present application;

[0087] FIG15 is a schematic diagram of the structure of a terminal provided in an embodiment of the present application;

[0088] FIG16 is a schematic diagram of the structure of the network device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0089] The technical solution provided in this application will be described below in conjunction with the accompanying drawings.

[0090] To facilitate understanding of the embodiments of the present application, the following points are first explained:

[0091] First, in this application, indications include explicit indications (also called direct indications) and implicit indications (also called indirect indications). Specifically, explicit indication information A refers to including information A; implicit indication information A refers to indicating information A through the correspondence between information A and information B and directly indicating information B. The correspondence between information A and information B can be predefined, pre-stored, pre-burned, or pre-configured; or, it can also refer to indicating information A through information B and preset rules.

[0092] Second, in this application, information C is used to determine information D, which includes both information D being determined solely based on information C and information D being determined based on information C and other information. Furthermore, information C can also be used to determine information D indirectly, for example, when information D is determined based on information E, and information E is determined based on information C.

[0093] Third, in this application, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship, but it does not exclude the situation where the previous and next associated objects are in an "and" relationship. The specific meaning can be understood in conjunction with the context. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c; a and b; a and c; b and c; or a and b and c. Where a, b, c can be single or multiple.

[0094] Fourth, in this application, prefixes such as "first" and "second" are used solely to distinguish between different items belonging to the same category and do not constrain the order, size, or quantity of the items. For example, "first information" and "second information" are simply different pieces of information; there is no temporal, size, or priority relationship between them.

[0095] Fifth, the "sending" and "receiving" in this application indicate the direction of signal transmission. For example, "sending information to a terminal" can be understood as the destination end of the information being the terminal, which can include direct sending through the air interface, and also includes indirect sending through the air interface by other units or modules. "Receiving information from a network device" can be understood as the source end of the information being the network device, which can include direct receiving from the network device through the air interface, and also includes indirect receiving from the network device through the air interface from other units or modules. "Sending" can also be understood as the "output" of the chip interface, and "receiving" can also be understood as the "input" of the chip interface.

[0096] In other words, sending and receiving can be performed between devices, for example, between a terminal and a network device; or it can be performed within a device, for example, sending or receiving between components, modules, chips, software modules or hardware modules within the device through a bus, wiring or interface.

[0097] Sixth, in the embodiments of the present application, "when", "if" and "if" all mean that the device will make corresponding processing under certain objective circumstances, which does not limit the time, and does not require the device to have a judgment action when it is implemented, nor does it mean that there are other limitations.

[0098] Seventh, in this application, words such as "example," "exemplarily," "for example," or "such as" are used to indicate examples, illustrations, or explanations. Any embodiment or design described in this application as "example," "exemplarily," "for example," or "such as" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "example," "exemplarily," "for example," or "such as" is intended to present the relevant concepts in a concrete manner.

[0099] Eighth, this document describes the communication method provided by this application using downlink channel measurement as an example, but this should not limit the scenarios to which this solution is applicable. In uplink channel measurement, after obtaining uplink channel state information (CSI), the network device can also perform RF channel reciprocity compensation of the network device and reversely calculate the uplink CSI to obtain the downlink CSI, which can also reduce signaling overhead. Based on the same concept, those skilled in the art can make simple transformations based on the embodiments of this document to obtain uplink CSI and downlink CSI. For the sake of brevity, this document will not go into details.

[0100] The technical solution provided in the embodiments of the present application can be applied to wireless local area network (WLAN) scenarios, for example, supporting Institute of Electrical and Electronics Engineers (IEEE) 802.11 related standards, such as 802.11a / b / g standards, 802.11n standards, 802.11ac standards, 802.11ax standards, IEEE 802.11ax next-generation Wi-Fi protocols, such as 802.11be, Wi-Fi 7, extremely high throughput (EHT), 802.11ad, 802.11ay or 802.11bf, and 802.11be next generation, Wi-Fi 8, etc., and can also be applied to ultra-wideband (UWB)-based Wireless personal area network systems based on ultra-wideband (UWB) wireless technologies, such as the 802.15 series of standards, can also be applied to sensing systems, such as the 802.11bf series of standards, and can also be applied to the 802.11bn standard or the ultra-high reliability (UHR) standard. The 802.11n standard is known as the high throughput (HT) standard, the 802.11ac standard is known as the very high throughput (VHT) standard, the 802.11ax standard is known as the high efficiency (HE) standard, and the 802.11be standard is known as the extremely high throughput (EHT) standard. 802.11bf includes two major categories of standards: low-frequency (e.g., sub7 GHz) and high-frequency (e.g., 60 GHz). Sub-7GHz implementations primarily rely on standards such as 802.11ac, 802.11ax, 802.11be, and their next-generation counterparts, while 60GHz implementations primarily rely on standards such as 802.11ad, 802.11ay, and their next-generation counterparts. 802.11ad is also known as the directional multi-gigabit (DMG) standard, and 802.11ay is also known as the enhanced directional multi-gigabit (EDMG) standard.

[0101] Although the embodiments of the present application are primarily described using the deployment of a WLAN network, particularly a network using the IEEE 802.11 system standard, as an example, those skilled in the art will readily appreciate that the various aspects of the embodiments of the present application can be extended to other networks using various standards or protocols, such as a high-performance wireless local area network (HIPERLAN), a wireless wide area network (WWAN), a wireless personal area network (WPAN), or other networks now known or developed in the future. Therefore, regardless of the coverage area and wireless access protocol used, the various aspects provided in the embodiments of the present application can be applied to any suitable wireless network.

[0102] The technical solutions of the embodiments of the present application can also be applied to various communication systems, such as: WLAN communication system, wireless fidelity (Wi-Fi) system, long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), world-wide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) system or new radio (NR), sixth generation (6G) system, Internet of Things (IoT) network or vehicle to x (V2X), etc.

[0103] The above-mentioned communication system applicable to the present application is only an example, and the communication system applicable to the present application is not limited to this. It is uniformly explained here and will not be repeated below. Figure 1 is a schematic diagram of the architecture of a communication system applicable to the communication method provided by the present application. Figure 1 shows a schematic diagram of a possible, non-restrictive system architecture. As shown in Figure 1, the communication system includes: a network device and a terminal. It should be understood that the network device in Figure 1 is an access point (AP) in a WLAN system as an example, and the terminal in Figure 1 is an example of a station (STA) in a WLAN system. The embodiments of the present application do not limit the number of network devices and terminals included in the communication system. For example, 2 APs and 3 STAs are taken as an example in Figure 1.

[0104] Terminals can access the communication network through network devices. Terminals can be wirelessly connected to network devices and can be fixed or mobile. The communication system may also include other network devices, such as core network devices, wireless relay devices, and wireless backhaul devices, which are not shown in Figure 1.

[0105] In some embodiments, the network device is an access device that the terminal uses to access the communication system wirelessly. For example, the network device can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation base station (gNB), a next-generation base station in a sixth-generation (6G) mobile communication system, a base station in a future mobile communication system, or an access point (AP) in a WiFi system, etc.

[0106] A terminal may also be referred to as a terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), etc. For example, a terminal may be a mobile phone, a tablet computer, a computer with wireless transceiver function, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, etc.

[0107] In the embodiments of the present application, the terminal and network device can be hardware devices, or software functions running on dedicated hardware, software functions running on general-purpose hardware, such as virtualization functions instantiated on a platform (for example, a cloud platform), or entities including dedicated or general-purpose hardware devices and software functions. The present application does not limit the specific form of the terminal and network device.

[0108] It should be understood that FIG1 is an illustration of a WLAN system, in which the network device may be an AP and the terminal may be an STA. In some embodiments, the STA may be a non-AP station (non-AP STA), referred to as a non-AP station or STA. Specifically, the solution of the present application is applicable to data communication between an AP and one or more non-AP stations (for example, data communication between AP1 and non-AP STA1 and non-AP STA2 in FIG1 ), and also to data communication between APs (for example, data communication between AP1 and AP2 in FIG1 ), and data communication between non-AP STAs and non-AP STAs (for example, data communication between non-AP STA2 and non-AP STA3 in FIG1 ).

[0109] An access point is a node that allows terminals (such as mobile phones) to access a wired (or wireless) network. It is primarily deployed in homes, buildings, and campuses, with a typical coverage radius of tens to hundreds of meters. It can also be deployed outdoors. An access point acts as a bridge between wired and wireless networks, connecting wireless network clients and then connecting the wireless network to the Ethernet.

[0110] Specifically, the access point can be a terminal or network device with a Wi-Fi chip, and the network device can be a server, a router, a switch, a bridge, a computer, a mobile phone, a relay station, a vehicle-mounted device, a wearable device, a network device in a 5G network, a network device in a 6G network, or a network device in a public land mobile network (PLMN), etc., and the embodiments of the present application are not limited thereto. The access point can be a device that supports the Wi-Fi standard. For example, the access point can also support one or more standards of the IEEE 802.11 series, such as 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax, 802.11be, 802.11ad, 802.11ay, 802.11bn, and 802.11bf.

[0111] A non-AP site may be a wireless communication chip, a wireless sensor, or a wireless communication terminal, and may also be referred to as a user, user equipment (UE), access terminal, subscriber unit, subscriber station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent, or user device. A non-AP site may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, an Internet of Things device, a wearable device, a terminal in a 5G network, a terminal in a 6G network, or a terminal in a PLMN, and the embodiments of the present application are not limited thereto. A non-AP site may be a device that supports the WLAN standard. For example, a non-AP station may support one or more standards in the IEEE 802.11 series, such as 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax, 802.11be, 802.11ad, 802.11ay, and 802.11bf.

[0112] For example, non-AP sites can be mobile phones, tablets, set-top boxes, smart TVs, smart wearable devices, in-vehicle communication devices, computers, Internet of Things (IoT) nodes, sensors, smart homes such as smart cameras, smart remote controls, smart water and electricity meters, and sensors in smart cities.

[0113] The above-mentioned AP or non-AP site may include a transmitter, a receiver, a memory, a processor, etc., wherein the transmitter and the receiver are used for sending and receiving packet structures respectively, the memory is used to store signaling information and store preset values ​​agreed in advance, etc., and the processor is used to parse signaling information, process related data, etc.

[0114] In order to better understand the method provided in the embodiments of the present application, the terms involved in the present application are briefly explained below.

[0115] 1. Channel reciprocity: Within a relatively short period of time (the coherence time of signal propagation), the channel fading experienced by the uplink and downlink channels can be assumed to be the same. It should be understood that the embodiments of this application focus on the reciprocity of RF channels (or links) in a device. It should be understood that the uplink and downlink channels in the following embodiments refer to both the uplink and downlink channels.

[0116] 2. Reciprocity calibration: In the embodiments of the present application, this refers to calibrating the downlink channel (e.g., the receiving channel in the terminal's RF channel) and the uplink channel (e.g., the transmitting channel in the terminal's RF channel) to obtain difference information between the downlink channel and the uplink channel when transmitting and receiving signals. In some embodiments, this difference information may include delay difference and / or phase difference. In some embodiments, the difference information between the downlink channel and the uplink channel when transmitting and receiving signals can be referred to as the reciprocity calibration result.

[0117] 3. Reciprocity compensation: In the embodiments of the present application, it refers to processing the downlink CSI based on the reciprocity calibration result to obtain the uplink CSI, or based on the reciprocity calibration result, performing reciprocity compensation (or reverse calculation) on the uplink CSI to obtain the downlink CSI.

[0118] 4. Reference signal (RS): can be used for channel measurement, channel estimation, etc.

[0119] According to the LTE or NR protocol, the downlink reference signal may include, for example: synchronization signal block (SSB), physical downlink control channel (PDCCH)-demodulation reference signal (PDCCH-DMRS), physical downlink shared channel (PDSCH)-demodulation reference signal (PDSCH-DMRS), PTRS, channel status information reference signal (CSI-RS), cell reference signal (CRS) in LTE, time / frequency domain tracking synchronization signal (TRS) in NR, downlink positioning signal (positioning RS), etc. Uplink reference signals may include, for example, sounding reference signal (SRS), physical uplink control channel (PUCCH)-demodulation reference signal (DMRS) (PUCCH-DMRS), physical uplink shared channel (PUSCH)-demodulation reference signal (PUSCH-DMRS), phase noise tracking reference signal (PTRS), uplink positioning RS, etc.

[0120] According to the WLAN protocol, the reference signal may be, for example, a null data packet announcement (NDP) frame.

[0121] 5. Reference signal configuration: Reference signal configuration can include reference signal resource configuration and reporting configuration. The following takes RS configuration as an example to introduce.

[0122] Among them, the reporting configuration can be used to configure parameters related to CSI reporting, such as "report configuration identifier (ReportConfigId)", "report configuration type (reportConfigType)", "report quantity (reportQuantity)," etc. "reportConfigId" can be used to indicate the reported information. "reportConfigType" is used to configure the reporting type, which can be specifically divided into: periodic reporting, semi-continuous reporting and non-periodic reporting. "reportQuantity" can be used to configure the reported information, such as: precoding matrix indicator (PMI), rank indicator (RI), layer indicator (LI), channel quality indicator (CQI), reference signal reception power (RSRP), reference signal reception quality (RSRQ), signal to noise ratio (SNR), signal to interference-noise ratio (SINR), etc. Different information can be reported through different configurations.

[0123] The reference signal resource configuration may be used to configure RS resource-related information, such as a “resource configuration identifier (CSI-ResourceConfigId)” and RS resources used for measurement.

[0124] It should be understood that the embodiments of the present application are applicable to various communication scenarios, but are particularly suitable for multiple-in-multi-out (MIMO) scenarios. In multiple-in-multi-out (MIMO) scenarios, network devices and terminals use two or more antennas to transmit information, forming an antenna system with multiple channels between the transmitter and the receiver. By independently sending information on different antennas, the utilization rate of the channels can be improved.

[0125] Here, in conjunction with Figure 2, a MIMO communication system is briefly introduced to facilitate understanding of the communication method provided in the embodiment of the present application.

[0126] For example, a network device with two antennas and a terminal with two antennas together form a 2×2 MIMO communication system. In a 2×2 MIMO communication system, spatial layers can be used to transmit different information in different layers. This layering approach is called spatial division multiplexing. After spatial division multiplexing, MIMO can be categorized into SU-MIMO and MU-MIMO. SU-MIMO refers to a layer used by a single user, while MU-MIMO allocates layers to different users.

[0127] Referring to Figure 2 , taking the example of a network device with two antennas, antenna 1 and antenna 2, and a terminal with two antennas, antenna 1 and antenna 2, a 2×2 MIMO communication system can include four spatial streams. These four spatial streams are: spatial stream 1 from antenna 1 of the network device to antenna 1 of the terminal, spatial stream 2 from antenna 1 of the network device to antenna 2 of the terminal, spatial stream 3 from antenna 2 of the network device to antenna 1 of the terminal, and spatial stream 4 from antenna 2 of the network device to antenna 2 of the terminal.

[0128] In some embodiments, a spatial stream can be viewed as a subchannel of a channel between a network device and a terminal. For example, referring to FIG2 , the channel between a network device and a terminal can be divided into four subchannels, and each spatial stream can serve as a subchannel. For example, the channel between a network device and a terminal can be divided into four subchannels, namely, subchannel 1 (the channel between antenna 1 of the network device and antenna 1 of the terminal), subchannel 2 (the channel between antenna 1 of the network device and antenna 2 of the terminal), subchannel 3 (the channel between antenna 2 of the network device and antenna 1 of the terminal), and subchannel 4 (the channel between antenna 2 of the network device and antenna 2 of the terminal).

[0129] For example, a network device sends signal X1 through antenna 1 and signal X2 through antenna 2. Due to the influence of the downlink channel, the terminal receives signal Y1 through antenna 1 and signal Y2 through antenna 2. The downlink channel information can be determined by the signals X1 and X2 sent by the transmitter (network device) and the signals Y1 and Y2 received by the receiver (terminal). For example, the downlink transmission matrix that reflects the downlink channel information can be called the H matrix, and the H matrix can satisfy the following formula 1:

[0130] Among them, h in the H matrix 11 、h 12 、h 21 , and h 22 Respectively represent the channel information of each subchannel of 2×2 MIMO transmission. For example, h 11 is the channel transmission coefficient of subchannel 1, h 12is the channel transmission coefficient of subchannel 2, h 21 is the channel transmission coefficient of subchannel 3, h 22 is the channel transmission coefficient of subchannel 4.

[0131] Currently in the LTE system, in order to improve the utilization rate of channel resources, the channel between the network device and the terminal can be divided into multiple subchannels (subchannel) or subbands (subband). The following subchannel is used as an example for explanation. Different subchannels have different frequencies. In order to ensure the communication quality between the network device and the terminal, the network device can perform frequency selection, that is, decide on which subchannel to send downlink information (signaling and / or data) to the terminal. Referring to Figure 3A, the network device can send a reference signal to the terminal. The terminal measures (or estimates) the downlink channel based on the received reference signal, obtains the CSI of the downlink channel, and feeds it back to the network device. Among them, the CSI of the downlink channel may include the CSI of each downlink subchannel. The network device can perform frequency selection based on the CSI of each downlink subchannel, and decide the resources, modulation and coding scheme (MCS) and precoding configuration of the downlink channel of the scheduling terminal.

[0132] In some embodiments, the CSI of the downlink channel may be referred to as downlink channel state information (downlink CSI), and the CSI of the uplink channel may be referred to as uplink channel state information (uplink CSI).

[0133] As various devices continue to permeate our daily lives, a growing number of mobile applications are placing higher demands on network communication quality. With the rise of applications such as wireless office, video conferencing, short videos, AR, and VR, users are placing higher demands not only on downlink communication quality (e.g., download speeds and video loading speeds), but also on uplink communication quality (e.g., multimedia resource uploads).

[0134] In order to ensure the communication quality of the uplink channel, uplink channel measurement can be performed at present. Based on the relevant protocols of LTE, the network device can allocate resources for sending reference signals to the terminal, and the terminal can send reference signals to the network device on the resources. After receiving the reference signal, the network device can measure the uplink channel to obtain uplink CSI. In some embodiments, the network device can communicate with multiple terminals at the same time, and because the resources for each terminal to send reference signals are not shared, the network device needs to allocate resources to each terminal. In order to improve the measurement efficiency of the uplink channel, referring to Figure 3B, the network device can allocate resources to multiple terminals in the frequency domain, and the terminals can send reference signals to the network device on the corresponding resources. It should be understood that Figure 3B takes multiple terminals including UE1, UE2 and UE3 as an example.

[0135] In some embodiments, in order to facilitate the distinction between the reference signal sent by the network device to the terminal and the reference signal sent by the terminal to the network device, the reference signal sent by the network device to the terminal can be used as a downlink reference signal, and the reference signal sent by the terminal to the network device can be used as an uplink reference signal.

[0136] Currently, in LTE systems, when measuring uplink channels, the terminal needs to send an uplink reference signal to the network device. The network device then measures the uplink channel based on the reference signal to obtain uplink CSI. This results in high signaling overhead and low uplink channel measurement efficiency.

[0137] Currently, downlink channel measurements can also be performed in WLAN systems. Based on WLAN protocols, as shown in Figure 4 , downlink channel measurements may include steps 1 through 4. WLAN protocols include, but are not limited to, IEEE 802.11, IEEE 802.15, or IEEE 802.11.

[0138] Step 1. The AP broadcasts a null data packet announcement (NDPA) frame (or message).

[0139] In a WLAN system, an AP can be considered a network device, and a station (STA) can be considered a terminal.

[0140] Currently, the AP can broadcast NDPA frames on all frequency band resources. NDPA frames are used to indicate the STAs participating in the channel measurement and the information that the STAs need to report.

[0141] In some embodiments, the format of the NDPA frame may refer to Table 1-1 and Table 1-2:

[0142] Table 1-1

[0143] Table 1-2

[0144] The first four fields in Table 1-1 are the frame header of the NDPA frame. Frame Control indicates the protocol version and frame type of the NDPA frame. Duration indicates a time period that indicates the total transmission time of the NDPA frame, the NDP frame, and the subsequent terminal feedback of channel information to the network device. If the NDPA frame carries only one STA information (information, info), the RA (receiver address) indicates the media access control (MAC) address of the terminal that needs to feedback channel information. If the NDPA frame contains multiple STA info, the RA is set to the broadcast address. TA (transmitter address) indicates the address of the network device sending the NDPA frame. Sounding Dialog Token indicates the index of the NDPA frame determined by the network device. STA Info indicates the information of the STAs participating in the channel measurement. STA Info1 to STA InfoN indicate the information of multiple STAs participating in the channel measurement. FCS indicates the frame check sequence.

[0145] In Table 1-2, AID 11 represents the terminal association identity for which channel information feedback is required. Partial BW Info represents the first 26-tone RU to the last 26-tone RU for which channel information feedback is required, wherein Partial BW Info may include RU start and RU end. RU start represents the first 26-tone RU for which channel information feedback is required, and RU end represents the last 26-tone RU for which channel information feedback is required. Feedback Type And Ng indicates the channel information that the STA needs to feedback, and the channel information may include, but is not limited to: channel quality indication (CQI), multi-user compressed V matrix (MUCV), and single user compressed V matrix (SU CV). In some embodiments, MUCV and SU CV can be understood as a type of PMI. Disambiguation represents an NDPA frame used to help the terminal identify a HE. Codebook Size and Feedback Type And Ng together characterize the quantization bit width of the channel information feedback. Nc represents the number of streams, which can be understood as the number of spatial streams that the MIMO communication system can transmit information.

[0146] Step 2: After a short interframe space (SIFS), the AP broadcasts an NDP frame.

[0147] NDP frame is used for channel measurement. In some embodiments, NDP frame can be used as a reference signal.

[0148] When the STA receives the NDP frame, it can use the NDP frame to measure the downlink channel and obtain the downlink CSI.

[0149] Step 3: After SIFS, the AP broadcasts a trigger frame.

[0150] Trigger frame, used to instruct STAs to report channel status information.

[0151] In some embodiments, the Trigger frame may include information such as the length of the physical layer protocol data unit (PHY protocol data unit, PPDU) and the modulation coding scheme (MCS).

[0152] Step 4: The STA reports downlink CSI to the AP.

[0153] In a WLAN system, the AP does not allocate frequency domain resources to STAs. Instead, it broadcasts NDPA frames, NDP frames, and Trigger frames across the entire frequency band. Therefore, STAs connected to the AP can receive these frames. For example, referring to Figure 4 , STA1 and STA2 receive NDPA frames, NDP frames, and Trigger frames. After receiving the Trigger frame, STA1 can report downlink CSI-1 to the AP after a SIFS, and STA2 can report downlink CSI-2 to the AP.

[0154] In some embodiments, downlink CSI may be carried in a compressed beamforming report. For example, STA1 may report compressed beamforming report 1 to the AP, including downlink CSI-1. Similarly, STA2 may report compressed beamforming report 2 to the AP, including downlink CSI-2.

[0155] Currently, relevant WLAN protocols do not disclose a communication method for an uplink channel.

[0156] In one possible scenario, STAs can take turns to report uplink reference signals to achieve uplink channel measurement. For example, the AP can broadcast a Trigger frame, which is used to instruct the STA to send an NDP frame (which can be regarded as an uplink reference signal), and the NDP frame is used by the AP to measure the uplink channel. In response to the Trigger frame, the STA can send an NDP frame to the AP across the entire frequency band. After receiving the NDP frame, the AP can measure the uplink channel and obtain the uplink CSI. It should be understood that when there are multiple STAs accessing the AP, the multiple STAs can send NDP frames to the AP at different times in response to the Trigger frame, that is, the STAs can take turns to report uplink reference signals, so that the AP can measure the uplink channel based on the uplink reference signal.

[0157] In one possible scenario, a WLAN system can use an uplink channel communication method similar to that used in LTE systems. For example, an AP can pre-allocate frequency domain resources for multiple STAs to transmit NDP frames and broadcast a trigger frame. In response to receiving the trigger frame, the multiple STAs can transmit NDP frames to the AP on the corresponding frequency domain resources. This allows the AP to measure the uplink channel based on the NDP frames received from the STAs and obtain uplink CSI.

[0158] Currently, no uplink channel communication method has been disclosed in WLAN systems. In a possible implementation, when measuring the uplink channel, STAs need to send uplink reference signals to the AP in a round-robin manner. The AP then measures the uplink channel based on the uplink reference signals to obtain uplink CSI. This results in high signaling overhead, affects the efficient use of air interface channel resources, and reduces uplink channel measurement efficiency.

[0159] Currently, when a network device sends a downlink reference signal to a terminal, the transmission of the downlink reference signal consists of two parts: spatial transmission and radio frequency transmission. In some embodiments, the channel between the network device and the terminal can be divided into a spatial channel and a radio frequency channel. The channel for spatial transmission can be called a spatial channel, and the channel for radio frequency transmission can be called a radio frequency channel.

[0160] Figure 5 is a schematic diagram of a channel between a network device and a terminal provided in an embodiment of the present application. Referring to Figure 5, taking subchannel 1 between antenna 1 of the network device and antenna 1 of the terminal as an example, the network device transmits a downlink reference signal through antenna 1 of the network device, and the downlink reference signal is transmitted through space and received by antenna 1 of the terminal. After antenna 1 receives the downlink reference signal, it will be processed by the RF channel of antenna 1 of the terminal and reach the processor of the terminal (such as a baseband processor). The processor of the terminal can measure the downlink channel according to the downlink reference signal to obtain the downlink CSI.

[0161] 5 , the RF channel of antenna 1 of the terminal includes a receiving channel and a transmitting channel. The receiving channel can receive a downlink reference signal from a network device, and the transmitting channel can send uplink information to the network device. In some embodiments, the receiving channel may include, but is not limited to, an amplifier, a filter, an analog-to-digital converter (ADC), a baseband processor, etc. The transmitting channel may include, but is not limited to, a baseband processor, a digital-to-analog converter (DAC), a filter, and an amplifier. After receiving the downlink reference signal, antenna 1 of the terminal can amplify, filter, perform analog-to-digital conversion, and other processing on the downlink reference signal through the various components in the receiving channel, and the baseband processor calculates the downlink CSI. As for the signal transmitted by the terminal, the signal can be subjected to digital-to-analog conversion, filtering, amplification, and other processing by the various components in the transmitting channel before being transmitted through the antenna.

[0162] In summary, during spatial transmission, the downlink reference signal is not processed by equipment, etc., so during spatial transmission, the uplink and downlink channels in the coherent time-space channel are reciprocal. During RF transmission, however, the receiving channel and the transmitting channel process the signal differently, resulting in delays and / or phase differences in the transmission of the signal in the receiving and transmitting channels. To ensure reciprocity of the uplink and downlink channels in the RF channel, the terminal can perform reciprocity calibration on the RF channel to ensure reciprocity of the uplink and downlink channels in the RF channel.

[0163] In view of this, an embodiment of the present application provides a communication method that can enable reciprocity of the uplink and downlink channels between the terminal and the network device with the help of the terminal's reciprocity calibration of the RF channel. In this way, after the terminal measures the downlink channel to obtain the downlink CSI, it can be based on the reciprocity of the uplink and downlink channels. Using the reciprocity calibration result of the terminal's RF channel, the downlink CSI is reversely calculated to complete the measurement of the uplink channel and obtain the uplink CSI.

[0164] In the present application, since there is no need to adopt a method in which the terminal sends an uplink reference signal to the network device, the network device completes the measurement of the uplink channel to obtain the uplink CSI. Instead, the uplink CSI is obtained by reverse calculation based on the downlink CSI, which can reduce signaling overhead and save air interface resources. In addition, since the uplink CSI is calculated from the downlink CSI, the terminal can report the uplink CSI when reporting the downlink CSI. There is no need to perform downlink channel measurement and uplink channel measurement in sequence, which can improve the measurement efficiency of the uplink channel.

[0165] The communication method provided by this application will be described in detail below with reference to the accompanying drawings.

[0166] Figure 6 is a schematic flow chart of a communication method provided in an embodiment of the present application. Figure 6 describes the method by taking the interaction between a network device and a terminal as an example, and should not constitute any limitation to the present application. The network device in Figure 6 can also be replaced by a component configured in the network device (such as a chip, a chip system, a processor, etc.), or a logic module or software that can implement all or part of the functions of the network device. The terminal can be replaced by a component configured in the terminal (such as a chip, a chip system, a processor, etc.), or a logic module or software that can implement all or part of the functions of the terminal.

[0167] 6 , the communication method provided in the embodiment of the present application may include:

[0168] S601: A network device sends a first reference signal.

[0169] For example, the first reference signal is a downlink reference signal.

[0170] In an LTE system, a network device may send a first reference signal to a terminal, and the terminal may receive the first reference signal. In a WLAN system, a network device may broadcast a first reference signal (e.g., an NDP frame), and a terminal (STA) that has accessed the network device (e.g., an AP) may receive the first reference signal.

[0171] In some embodiments, the network device may send a first reference signal to the terminal periodically or non-periodically. A scenario in which the first reference signal is sent to the terminal non-periodically is, for example: when the position change of the terminal exceeds a threshold, the network device may send a first reference signal to the terminal, instructing the terminal to re-measure the downlink channel. Alternatively, when the downlink CSI indicates that the network quality of the downlink channel is less than a threshold, the network device may send a first reference signal to the terminal, instructing the terminal to re-measure the downlink channel. The embodiments of the present application do not limit the scenario in which the first reference signal is sent to the terminal non-periodically. The following embodiments are described by taking the network device periodically sending the first reference signal to the terminal as an example.

[0172] S602: The terminal sends first uplink channel state information to a network device. The first uplink channel state information is obtained by performing radio frequency channel reciprocity compensation on first downlink channel state information. The first downlink channel state information is obtained based on a first reference signal.

[0173] As previously mentioned, the downlink reference signal is used by the terminal to measure the downlink channel and obtain downlink CSI. In an embodiment of the present application, in response to receiving the first reference signal, the terminal can measure the downlink channel and obtain downlink CSI. This embodiment of the present application does not describe this process in detail, and reference can be made to the description in the relevant protocol. In some embodiments, the downlink CSI obtained from the first reference signal can be referred to as the first downlink CSI. In other words, the first downlink CSI is obtained based on the first reference signal, or the first downlink CSI is obtained by measuring the downlink channel based on the first reference signal.

[0174] As previously mentioned, to ensure reciprocity between the uplink and downlink channels between the terminal and the network device, the terminal can perform reciprocity calibration on the terminal's RF channel to obtain a reciprocity calibration result for the RF channel. In an embodiment of the present application, the terminal can perform reciprocity compensation on the first downlink CSI based on the reciprocity calibration result to obtain the first uplink CSI. In other words, the terminal performs a reverse calculation on the first downlink CSI based on the reciprocity calibration result to obtain the first uplink CSI. In other words, the terminal performs a reverse calculation of the reciprocity of the uplink channel based on the reciprocity calibration result to obtain the first uplink CSI.

[0175] In some embodiments, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the RF channels corresponding to each antenna. Referring to Figure 5, for one antenna of the terminal, one antenna corresponds to one RF channel, and the RF channel corresponding to the antenna refers to: the RF channel connected to the antenna. For example, the signal received by the antenna can be transmitted to the RF channel for processing, and the signal sent by the RF channel can be transmitted via the antenna. A RF channel includes a receiving channel and a transmitting channel. In other words, one antenna corresponds to a group of transceiver channels, and the transceiver channel includes a receiving channel and a transmitting channel.

[0176] In some embodiments, the terminal performing reciprocity calibration on the RF channel can be understood as: the terminal performing reciprocity calibration on the RF channel corresponding to each antenna, and accordingly, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the RF channels corresponding to each antenna. Among them, the delay difference and / or phase difference between the RF channels corresponding to each antenna may include: the delay difference and / or phase difference between the transmitting channels corresponding to each antenna, and the delay difference and / or phase difference between the receiving channels corresponding to each antenna. Taking the terminal including antenna 1 and antenna 2 as an example, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the transmitting channel corresponding to antenna 1 of the terminal and the transmitting channel corresponding to antenna 2, and the delay difference and / or phase difference between the receiving channel corresponding to antenna 1 of the terminal and the receiving channel corresponding to antenna 2.

[0177] The antenna numbers (e.g., antenna 1 and antenna 2) in the above embodiment can be regarded as antenna indices defined in the standard protocol. The antennas involved in the reciprocity calibration results of the RF channel (e.g., antenna 1 and antenna 2) can be used to receive and transmit signals. In this application, the number of transmitting antennas of the terminal is equal to the number of spatial streams, and the number of receiving antennas can be equal to the actual number of receiving channels. The transmitting antenna can transmit signals, and the receiving antenna can transmit signals.

[0178] The time delay difference and / or phase difference between the radio frequency channels defined in the embodiments of the present application can actually be regarded as the time delay difference and / or phase difference relative to the radio frequency channel corresponding to the reference antenna (such as antenna 1). Exemplarily, taking the terminal including antenna 1 and antenna 2 as an example, the reference antenna can be antenna 1 or antenna 2, and taking the reference antenna as antenna 1 as an example, the reciprocity calibration result of the radio frequency channel may include: the time delay difference and / or phase difference between the radio frequency channel corresponding to antenna 2 and the radio frequency channel corresponding to antenna 1. Specifically, the reciprocity calibration result of the radio frequency channel may include: the time delay difference and / or phase difference between the receiving channel corresponding to antenna 2 and the receiving channel corresponding to antenna 1, and the time delay difference and / or phase difference between the transmitting channel corresponding to antenna 2 and the transmitting channel corresponding to antenna 1.

[0179] Exemplarily, taking the case where the terminal includes antenna 1, antenna 2, and antenna 3, the reference antenna may be antenna 1, antenna 2, or antenna 3. Taking antenna 1 as the reference antenna, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the RF channel corresponding to antenna 2 and the RF channel corresponding to antenna 1, and the delay difference and / or phase difference between the RF channel corresponding to antenna 3 and the RF channel corresponding to antenna 1. Specifically, the reciprocity calibration result of the RF channel may include: the delay difference and / or phase difference between the receiving channel corresponding to antenna 2 and the receiving channel corresponding to antenna 1, the delay difference and / or phase difference between the receiving channel corresponding to antenna 3 and the receiving channel corresponding to antenna 1, and the delay difference and / or phase difference between the transmitting channel corresponding to antenna 2 and the transmitting channel corresponding to antenna 1, and the delay difference and / or phase difference between the transmitting channel corresponding to antenna 3 and the transmitting channel corresponding to antenna 1.

[0180] It should be understood that the following embodiments are described using the example of a terminal including antenna 1 and antenna 2. The solution of this application can also be applied to a terminal including more antennas. A person skilled in the art can apply the solution of this application by making simple modifications based on the embodiments of this application based on the same concept, and this will not be described in detail herein.

[0181] For example, taking the terminal including antenna 1 and antenna 2 as an example, the reciprocity calibration result A of the radio frequency channel can be expressed as the following formula 2: A=((θ r,2 +2πfτ r,2)-(θ r,1 +2πfτ r,1 ))-((θ t,2 +2πfτ t,2 )-(θ t,1 +2πfτ t,1 )) Formula 2

[0182] Among them, θ r,2 Indicates the initial phase value of the receiving channel corresponding to the terminal's antenna 2, θ r,1 Indicates the initial phase value of the receiving channel corresponding to the terminal's antenna 2, θ t,2 Indicates the initial phase value of the transmission channel corresponding to antenna 2 of the terminal, θ t,1 Indicates the initial phase value of the transmission channel corresponding to antenna 1 of the terminal, τ r,2 represents the delay of the receiving channel corresponding to the terminal's antenna 2, τ r,1 Indicates the delay of the receiving channel corresponding to the terminal's antenna 1, τ t,2 represents the delay of the transmission channel corresponding to antenna 2 of the terminal, τ t,1 Indicates the delay of the receiving channel corresponding to antenna 1 of the terminal.

[0183] Taking antenna 1 as the reference antenna, when the terminal includes more antennas, Formula 2 can be referred to, and the delay difference and / or phase difference between the RF channels corresponding to other antennas and the RF channel corresponding to antenna 1 can also be obtained accordingly.

[0184] It should be understood that θ and φ in this application are merely parameters that characterize the corresponding parameters and are not limited to terminals or network devices. The meanings of θ and φ can be determined by referring to the description below the formula.

[0185] In some embodiments, referring to Figure 7, after the terminal establishes a connection with the network device, the terminal can periodically perform reciprocity calibration on the terminal's radio frequency channel. The reciprocity calibration result of a radio frequency channel can be stable for about tens of minutes. Taking the network device periodically sending a first reference signal to the terminal as an example, this period is usually on the order of 10ms, so the measurement period of the downlink channel is much smaller than the period of the reciprocity calibration of the radio frequency channel. In other words, after the terminal performs a reciprocity calibration on the radio frequency channel, the terminal can perform at least one downlink channel detection, that is, the network device can periodically send at least one first reference signal to the terminal. Among them, the terminal can measure the downlink channel once in response to each first reference signal to obtain a first downlink CSI. In addition, for the first downlink CSI, the terminal can reversely calculate the first downlink CSI based on the reciprocity calibration result of the radio frequency channel to obtain the first uplink CSI.

[0186] The following describes a process in which the terminal reversely calculates the first downlink CSI to obtain the first uplink CSI based on the reciprocity calibration result of the RF channel:

[0187] Taking a 2×2 MIMO communication system as an example, the first downlink CSI can be expressed in matrix form as shown in the following formula 3:

[0188] Among them, τ d,sync Indicates the synchronization delay of the downlink channel between the network device and the terminal, and d represents the downlink channel. r,1 Indicates the initial phase value of the receiving channel corresponding to antenna 1 of the terminal, φ r,2 Indicates the initial phase value of the receiving channel corresponding to antenna 2 of the terminal. Indicates the delay of the receiving channel corresponding to antenna 1 of the terminal, Indicates the delay of the receiving channel corresponding to the terminal's antenna 2. t,1 Indicates the initial phase value of the transmission channel corresponding to antenna 1 of the network device, θ t,2 Indicates the initial phase value of the receiving channel corresponding to antenna 2 of the network device. Indicates the delay of the transmission channel corresponding to antenna 1 of the network device. Indicates the delay of the transmission channel corresponding to antenna 2 of the network device. 11 (f) represents the channel transmission coefficient of subchannel 1, h 12 (f) represents the channel transmission coefficient of subchannel 2, h 21 (f) represents the channel transmission coefficient of subchannel 3, h 22 (f) represents the channel transmission coefficient of subchannel 4.

[0189] It should be noted that due to the transposition of the uplink channel and the downlink channel in mathematical expression, the formula 3 There are position changes on the diagonal elements.

[0190] Similarly, the uplink CSI can also be expressed in matrix form, as shown in the following formula 4:

[0191] Among them, τ u,sync θ represents the synchronization delay of the uplink channel between the network device and the terminal, and u represents the uplink channel. r,1 Indicates the initial phase value of the receiving channel corresponding to antenna 1 of the network device, θ r,2 Indicates the initial phase value of the receiving channel corresponding to antenna 2 of the network device. Indicates the delay of the receiving channel corresponding to antenna 1 of the network device. Indicates the delay of the receiving channel corresponding to antenna 2 of the network device.t,1 Indicates the initial phase value of the transmission channel corresponding to antenna 1 of the terminal, φ t,2 Indicates the initial phase value of the transmission channel corresponding to antenna 2 of the terminal. Indicates the delay of the transmission channel corresponding to antenna 1 of the terminal, Indicates the delay of the transmission channel corresponding to antenna 2 of the terminal.

[0192] because The common part of the initial phase value does not affect the reverse calculation of the channel state information. For the convenience of expression, we first calculate H DL Simplify the process and get As shown in the following formula 5:

[0193] According to the reciprocity calibration results of the RF channel, Reciprocity compensation can be performed to obtain the first uplink CSI, which is expressed as For details, please refer to the following formula 6:

[0194] Among them, U θ Represents the reciprocity calibration result of the RF channel of the network equipment, U φ Indicates the reciprocity calibration result of the terminal's radio frequency channel. Because in this application, the terminal measures the downlink to obtain the first downlink CSI, and the terminal reversely calculates the first uplink CSI based on the first downlink CSI, only the reciprocity calibration result of the terminal's radio frequency channel is needed, without considering the reciprocity calibration result of the radio frequency channel of the network device. Therefore, in this application, the terminal can perform reciprocity calibration of the radio frequency channel of the terminal according to the reciprocity calibration result of the radio frequency channel of the terminal. Reciprocity compensation can be performed to obtain the first uplink CSI, which is expressed as As shown in the following formula 7:

[0195] Based on formula 7, we can get the first uplink CSI The delay difference and / or phase difference between the radio frequency channels corresponding to the first reference signal are associated. The radio frequency channel corresponding to the first reference signal can be understood as the radio frequency channel in the terminal that receives the first reference signal. For example, the terminal includes antenna 1 and antenna 2, and antenna 1 and antenna 2 both receive the first reference signal. Then the radio frequency channel corresponding to the first reference signal may include the radio frequency channel of antenna 1 and the radio frequency channel of antenna 2 of the terminal. represents the phase difference and delay difference between the receiving channel of antenna 2 and antenna 1 of the terminal, where φ r,2 -φ r,1Indicates the phase difference between the receiving channel of antenna 2 and the receiving channel of antenna 1 of the terminal. Indicates the delay difference between the receiving channel of antenna 2 and the receiving channel of antenna 1 of the terminal. represents the phase difference and delay difference between the transmission channel of antenna 2 and antenna 1 of the terminal, where φ t,2 -φ t,1 Indicates the phase difference between the transmission channel of antenna 2 and the transmission channel of antenna 1 of the terminal, Indicates the delay difference between the transmission channel of antenna 2 and the transmission channel of antenna 1 of the terminal.

[0196] It should be understood that the reciprocity calibration result U of the terminal's radio frequency channel in formula 7 is φ Including: the phase difference and delay difference between the receiving channel of antenna 2 of the terminal and the receiving channel of antenna 1, and the phase difference and delay difference between the transmitting channel of antenna 2 and the transmitting channel of antenna 1. In some embodiments, U φ It may include the phase difference and / or delay difference between the receiving channel of antenna 2 of the terminal and the receiving channel of antenna 1, as well as the phase difference and / or delay difference between the transmitting channel of antenna 2 and the transmitting channel of antenna 1.

[0197] In other words, the first uplink CSI is associated with the delay difference and / or phase difference between the radio frequency channels corresponding to the first reference signal. The delay difference and / or phase difference between the radio frequency channels may include: the delay difference and / or phase difference between the receiving channels of the terminal. In other words, the first uplink CSI is associated with the delay difference and / or phase difference between the receiving channels corresponding to the first reference signal. The receiving channel corresponding to the first reference signal can be understood as the receiving channel in the radio frequency channel corresponding to the first reference signal. For example, for example, the terminal includes antenna 1 and antenna 2, and antenna 1 and antenna 2 both receive the first reference signal. The radio frequency channel corresponding to the first reference signal may include the radio frequency channel of antenna 1 and the radio frequency channel of antenna 2 of the terminal, and the receiving channel corresponding to the first reference signal includes the receiving channel in the radio frequency channel of antenna 1 and the receiving channel in the radio frequency channel of antenna 2. The transmitting channel corresponding to the first reference signal includes the transmitting channel in the radio frequency channel of antenna 1 and the transmitting channel in the radio frequency channel of antenna 2.

[0198] In the embodiment of the present application, after obtaining the first downlink CSI and the first uplink CSI, the terminal may report the first downlink CSI and the first uplink CSI to the network device.

[0199] For example, the first downlink CSI and the first uplink CSI can be carried in a single message. In a WLAN system, for example, the first downlink CSI and the first uplink CSI can be carried in a compressed beamforming report. In some embodiments, a STA can encapsulate the first downlink CSI and the first uplink CSI in a compressed beamforming report. The first uplink CSI and the first downlink CSI can be written to the same resource as the first downlink CSI, or the first uplink CSI can be written to a reserved resource.

[0200] Exemplarily, the first downlink CSI and the first uplink CSI may be carried in different messages. Exemplarily, the terminal may first send the first downlink CSI to the network device, and then send the first uplink CSI to the network device. For example, when the first downlink CSI is calculated, the terminal may first send the first downlink CSI to the network device, and when the terminal obtains the first uplink CSI by reversely calculating the first downlink CSI, the terminal may send the first uplink CSI to the network device. Alternatively, after obtaining the first downlink CSI and the first uplink CSI, the terminal may first send the first downlink CSI to the network device, and then send the first uplink CSI to the network device. This embodiment of the present application does not limit this. Taking the WLAN system as an example, in which the STA reports the first downlink CSI and the first uplink CSI to the AP, the STA may carry the first downlink CSI in a compressed beamforming report and send the compressed beamforming report to the network device. After sending the compressed beamforming report, the STA may send a message (or information) carrying the first uplink CSI to the network device.

[0201] It should be understood that FIG6 shows the steps of the terminal reporting the first downlink CSI and the first uplink CSI to the network device.

[0202] In an embodiment of the present application, a network device sends a first reference signal to a terminal. The terminal can measure a downlink channel based on the first reference signal to obtain a first downlink CSI. The terminal can reversely calculate (or reciprocity compensate) the first downlink CSI based on the reciprocity calibration result of the terminal's radio frequency channel to obtain a first uplink CSI. In an embodiment of the present application, the uplink channel measurement does not need to be implemented through signaling interaction. Instead, the uplink CSI is obtained by reversely calculating the downlink CSI based on the reciprocity of the channel, which can reduce signaling overhead, save air interface resources, and improve the measurement efficiency of the uplink channel.

[0203] In the embodiment shown in Figure 6, the terminal has the ability to report downlink CSI and uplink CSI. The terminal's ability to report downlink CSI and uplink CSI can be understood as: the terminal includes uplink CSI when reporting downlink CSI, or the terminal can obtain uplink CSI based on the reciprocity calibration result of the downlink CSI and the terminal's radio frequency channel, and the terminal can include uplink CSI when reporting downlink CSI.

[0204] In some embodiments, the terminal may report to the network device that the terminal has the capability to report downlink CSI and uplink CSI. For example, the terminal may send second information to the network device, where the second information is used to indicate that the terminal has the capability to report downlink CSI and uplink CSI.

[0205] In a WLAN system, a terminal accessing a network device (AP) may include three steps: scanning, authentication, and association. In some embodiments, the terminal may send second information to the network device during the association step.

[0206] Current WLAN protocols stipulate that during the association process, a terminal may send an association request to a network device. This association request may include various parameters of the terminal itself, as well as parameters selected based on the service configuration. For example, the association request may include the terminal's supported rates and channels, as well as the selected access authentication and encryption algorithms. In embodiments of the present application, the association request may include second information. Alternatively, the association request may include information indicating the ability to report CSI and uplink CSI. The association request may be considered the second information.

[0207] In some embodiments, the terminal may also send second information to the network device after the association step.

[0208] Similarly, in an LTE system, a terminal can send the second information to a network device during the process of establishing a connection with the network device. For example, based on current LTE protocol specifications, in some embodiments, the terminal can include the second information when reporting its capability information to the network device. Alternatively, the terminal can send the second information to the network device after establishing a connection with the network device.

[0209] In an embodiment of the present application, during the process of establishing a connection between a terminal and a network device, or after the terminal accesses the network device, because the terminal can report its own capability information to the network device, the network device can determine whether the terminal has the ability to report downlink CSI and uplink CSI based on the capability information on the terminal. When the terminal does not have the ability to report downlink CSI and uplink CSI, the network device can adopt the communication method of the uplink channel in the existing protocol to obtain uplink CSI. When the terminal has the ability to report downlink CSI and uplink CSI, the network device and the terminal can obtain downlink CSI and uplink CSI according to the communication method provided in the embodiment of the present application.

[0210] In some embodiments, the second information is further used to indicate whether the terminal supports reciprocity calibration of the RF channel. In this way, the network device can determine whether the terminal supports reciprocity calibration of the RF channel based on the second information. When the terminal supports reciprocity calibration of the RF channel, the terminal can complete the reciprocity calibration of the RF channel without the participation of the network device, as shown in the embodiment of Figure 9. When the terminal does not support reciprocity calibration of the RF channel, the terminal needs to interact with the network device to implement terminal-to-terminal reciprocity calibration of the RF channel, as shown in the embodiment of Figure 10.

[0211] Whether in an LTE system or a WLAN system, when a network device instructs a terminal to perform downlink channel measurement, it can instruct the terminal to report information. For example, in an LTE system, the network device can perform a reporting configuration so that the terminal can determine the parameters related to CSI reporting based on the reporting configuration. The reporting configuration can be configured in the first reference signal. In an embodiment of the present application, the terminal has the ability to report downlink CSI and uplink CSI, and the network device can configure the parameters related to CSI reporting in the reporting configuration. The parameters related to CSI reporting are used to indicate uplink CSI and downlink CSI. In this way, the terminal can determine that the measurement of the downlink channel needs to report uplink CSI and downlink CSI based on the reporting configuration.

[0212] For example, in a WLAN system, a network device may send an NDPA frame to a terminal, where the NDPA frame indicates information that the terminal needs to report. In some embodiments, the NDPA frame may be considered as first information, where the first information indicates the reporting of downlink CSI and uplink CSI. For example, the feedback type indicator bit in the NDPA frame may indicate the reporting of downlink CSI and uplink CSI.

[0213] The following describes the communication method provided by the embodiment of the present application using a WLAN system as an example. Referring to FIG8 , the communication method provided by the embodiment of the present application may include:

[0214] S801: AP broadcasts an NDPA frame.

[0215] S802: After SIFS, the AP broadcasts an NDP frame.

[0216] S803: After SIFS, the AP broadcasts a Trigger frame.

[0217] S804: The STA reports downlink CSI and uplink CSI to the AP.

[0218] The STA can determine, based on the NDPA frame, that uplink and downlink CSI reporting is required for this downlink channel measurement. Based on the NDP frame, the STA can measure the downlink channel and obtain the downlink CSI. Based on the reciprocity calibration results of the terminal's RF channel, the STA can reverse-calculate the downlink CSI to obtain the uplink CSI, as described in S602. Accordingly, the STA can report the downlink and uplink CSI to the AP.

[0219] As described in the above embodiments, a method for a terminal to reversely calculate downlink CSI based on the reciprocity calibration results of the RF channels to obtain uplink CSI is described. In some embodiments, the terminal may support self-calibration, that is, the terminal may perform reciprocity calibration on the RF channels to obtain the delay difference and / or phase difference between the terminal's RF channels. For example, in the case where the terminal includes antenna 1 and antenna 2, the delay difference and / or phase difference between the RF channels includes the delay difference and / or phase difference between the receiving channel of antenna 1 and the receiving channel of antenna 2.

[0220] For example, a terminal includes two antennas, antenna 1 and antenna 2. Referring to FIG9 , the terminal can perform the following steps to perform reciprocity calibration on the RF channel:

[0221] S901: The terminal sends a first signal through the transmission channel of antenna 1.

[0222] S902: The terminal receives a first signal through a receiving channel of antenna 2.

[0223] S903: The terminal sends a second signal through the transmission channel of antenna 2.

[0224] S904: The terminal receives a second signal through the receiving channel of antenna 1.

[0225] There is no order between S901-S902 and S903-S904, and they can be executed simultaneously.

[0226] S905: The terminal determines a delay difference and / or a phase difference between radio frequency channels of the terminal according to the transmitted first signal, the received first signal, the transmitted second signal, and the received second signal.

[0227] Among them, the delay difference and / or phase difference between the radio frequency channels includes: the delay difference and / or phase difference between the receiving channel of antenna 1 and the receiving channel of antenna 2, and the delay difference and / or phase difference between the transmitting channel of antenna 1 and the transmitting channel of antenna 2.

[0228] The terminal can perform reciprocity self-calibration of the RF channel through self-transmission and reception. The first signal sent by the transmitting channel corresponding to antenna 1 is received by the receiving channel corresponding to antenna 2 through spatial transmission, thereby completing the measurement of the transmitting channel corresponding to antenna 1 and the receiving channel corresponding to antenna 2. The first signal sent by the terminal and the first signal received can obtain the following information B, see formula 8: B = (θ r,2 +2πfτ r,2 )+(θ t,1 +2πfτ t,1 ) Formula 8

[0229] Among them, the second signal sent by the transmitting channel corresponding to antenna 2 is received by the receiving channel corresponding to antenna 1 after spatial transmission, thereby completing the measurement of the transmitting channel corresponding to antenna 2 and the receiving channel corresponding to antenna 1. The second signal sent and the second signal received by the terminal can obtain the following information C, see Formula 9: C = (θ r,1 +2πfτ r,1 )+(θ t,2 +2πfτ t,2 ) Formula 9

[0230] According to the above formulas 8 and 9, the terminal can obtain the reciprocity calibration result A of the RF channel, as shown in the following formula 10: A = BC Formula 10

[0231] In some embodiments, the terminal does not support self-calibration and cannot perform reciprocity calibration on the RF channel by itself. In this example, the terminal and the network device can exchange reference signals to implement reciprocity calibration of the RF channel by the terminal. Referring to Figure 10, the process may include:

[0232] S1001: A terminal sends a second reference signal to a network device.

[0233] In an embodiment of the present application, the terminal may proactively initiate a reciprocity calibration request to the network device, wherein the terminal may send a second reference signal to the network device.

[0234] The second reference signal is an uplink reference signal. In some embodiments, for example, the uplink reference signal may be a sounding reference signal (SRS), a physical uplink control channel (PUCCH)-demodulation reference signal (DMRS) (PUCCH-DMRS), a physical uplink shared channel (PUSCH)-demodulation reference signal (PUSCH-DMRS), a phase noise tracking reference signal (PTRS), an uplink positioning RS, etc. In some embodiments, for example, the uplink reference signal may be an NDP frame.

[0235] S1002: The network device sends a second uplink CSI to the terminal, where the second uplink CSI is obtained based on a second reference signal.

[0236] After receiving the second reference signal, the network device can measure the uplink channel and obtain the CSI of the uplink channel. The CSI of the uplink channel can be referred to as the second uplink CSI. The specific communication method can refer to the relevant description of the terminal obtaining the first downlink CSI based on the first reference signal, or refer to the relevant provisions in the existing protocol.

[0237] S1003: The network device sends a third reference signal to the terminal.

[0238] S1004: The terminal measures the downlink channel based on the third reference signal to obtain second downlink CSI.

[0239] It should be understood that there is no order in which S1002 and S1003 - S1004 may be executed simultaneously.

[0240] S1004 may refer to the relevant description of the terminal obtaining the second downlink CSI according to the third reference signal, or refer to relevant provisions in an existing protocol.

[0241] S1005: The terminal obtains a delay difference and / or a phase difference between radio frequency channels of the terminal according to the second downlink CSI and the second uplink CSI.

[0242] For example, a terminal includes two antennas, each corresponding to a radio frequency channel, which can include a receive channel and a transmit channel. The following uses the radio frequency channel corresponding to antenna 1 and the radio frequency channel corresponding to antenna 2 as examples to illustrate the reciprocity calibration process of the terminal for the radio frequency channel corresponding to antenna 1 and the radio frequency channel corresponding to antenna 2:

[0243] Step 1: Calculate the phase difference between the RF channels corresponding to each antenna of the terminal. The phase difference between the RF channels corresponding to each antenna includes: the phase difference between the transmitting channel of antenna 2 and the transmitting channel of antenna 1, and the phase difference between the receiving channel of antenna 2 and the receiving channel of antenna 1.

[0244] The phase difference between the radio frequency channels corresponding to the antennas of the terminal can be expressed as shown in the following formula 11:

[0245] in, represents the transmission channel of antenna 1 of the terminal, and the propagation channel h 11 The phase information formed together with the network device receiving antenna 1, represents the receiving channel of antenna 1 of the terminal, and the propagation channel h 11 The phase value formed together with the network device transmitting antenna 1, represents the transmission channel of antenna 2 of the terminal, and the propagation channel h 21 The initial phase value formed together with the network device receiving antenna 1, represents the receiving channel of antenna 2 of the terminal, and the propagation channel h 21 The initial phase value formed together with the network device transmitting antenna 1. Indicates the phase difference between the transmission channel of antenna 2 and the transmission channel of antenna 1 of the terminal, Indicates the phase difference between the receiving channel of antenna 2 and the receiving channel of antenna 1 of the terminal.

[0246] Because h ij (f) If there is reciprocity between the uplink and downlink, then Formula 11 can be simplified to Formula 12, as shown below:

[0247] When one end (such as a terminal) has complete uplink and downlink CSI, reciprocity calibration of the RF channel can be achieved. For a broadband system, full-band CSI feedback inevitably introduces information feedback overhead. Considering the linear relationship between the reciprocity calibration coefficient of the transmit and receive channels and the carrier f, the reciprocity calibration coefficients on some carriers can be obtained by linear interpolation of the coefficients on other carriers.

[0248] The phase difference between RF channels has a linear relationship with frequency. Through linear fitting, the phase difference between the terminal's RF channels and frequency can be obtained as shown in Figure 11:

[0249] Referring to Figure 11, the y-axis in Figure 11 is the phase difference between the uplink RF channel and the downlink RF channel. For each pair of uplink and downlink sub-channels, a phase difference between the uplink and downlink RF channels can be calculated. The x-axis in Figure 11 is the frequency of the sub-channel. Figure 11 shows h 11 , h 21 , h 12 , h 22 It should be understood that in FIG11 Take this as an example to illustrate.

[0250] Considering that formula 11 can be transformed into the following formula 13:

[0251] Therefore, in order to help the other end to calibrate the reciprocity of the RF channel, the network device only needs to feedback Phase differences on some carriers in the GPIO are calculated. Based on the phase differences on these carriers, the terminal can recover the channel reciprocity calibration coefficients for these carriers. The terminal can calculate the channel reciprocity calibration coefficients for all carriers using linear interpolation. The extracted feedback carrier interval can be fed back at a granularity of Ng.

[0252] Combining the above formula with FIG11, it can be determined that the phase difference between the RF channels of the terminal can be expressed as shown in the following formula 14, and the delay difference between the RF channels of the terminal can be expressed as shown in the following formula 15: (θ r,2 -θ r,1 )-(θ t,2 -θ t,1 )=b21-b11=b22-b12 Formula 14 (τ r,2 -τ r,1 )-(τ t,2 -τ t,1 )=k21-k11=k22-k12 Formula 15

[0253] Here, referring to FIG11, h 11 The slope of the linear fitting result of the phase difference and frequency between the corresponding RF channels is represented by k11, and the intersection with the y-axis is b11. Similarly, h 12 The slope of the linear fitting result of the phase difference and frequency between the corresponding RF channels is expressed as k12, and the intersection with the y-axis is b12, h 21 The slope of the linear fitting result of the phase difference between the corresponding RF channels and the frequency is represented by k21, the intersection with the y-axis is b21, and h22 The slope of the linear fitting result of the phase difference between the corresponding RF channels and the frequency is represented by k22, and the intersection with the y-axis is b22.

[0254] Therefore, in conjunction with Figure 11, the terminal can implement reciprocity calibration of the terminal's RF channels, and can obtain the phase difference between the terminal's RF channels, as shown in Formula 14, and the delay difference between the terminal's RF channels, as shown in Formula 15. Furthermore, the terminal can reversely calculate the first downlink CSI based on the phase difference and / or delay difference to obtain the first uplink CSI.

[0255] In the embodiments of the present application, terminals that support self-calibration can independently perform reciprocity calibration of the RF channel. Terminals that do not support self-calibration can exchange reference signals with a network device and, in combination with the second uplink CSI and the second downlink CSI, perform reciprocity calibration of the RF channel. After the terminal performs reciprocity calibration on the RF channel, it can execute the steps of the communication method provided in the above embodiments.

[0256] Referring to Figure 12, in an example in which a terminal and a network device exchange reference signals to implement reciprocity calibration of a radio frequency channel, the terminal may periodically initiate a reciprocity calibration request to the network device, and the terminal and the network device exchange reference signals so that the terminal can implement reciprocity calibration of the radio frequency channel in combination with the second uplink CSI and the second downlink CSI. After the terminal performs reciprocity calibration on the radio frequency channel, the terminal may perform at least one downlink channel detection, that is, the network device may periodically send at least one first reference signal to the terminal. In response to each first reference signal, the terminal may measure the downlink channel once to obtain a first downlink CSI. In addition, for the first downlink CSI, the terminal may perform a reverse calculation on the first downlink CSI based on the reciprocity calibration result of the radio frequency channel to obtain the first uplink CSI. The terminal reaches the first uplink CSI based on the reciprocity calibration result of the first CSI and the radio frequency channel, and reference may be made to the description in S602.

[0257] The communication method provided by the embodiment of the present application is described in detail above with reference to the accompanying drawings. Below, the device provided by the embodiment of the present application is described in detail with reference to the accompanying drawings.

[0258] Figures 13 to 16 are schematic block diagrams of possible communication devices provided by embodiments of the present application. These communication devices can be used to implement the functions of the terminal or network device in the above-mentioned method embodiment, and thus can also achieve the beneficial effects possessed by the above-mentioned method embodiment. In an embodiment of the present application, the communication device can be the terminal or network device in the method embodiment described above, or it can be a component (such as a chip, a chip system, a processor, etc.) configured in the terminal or network device, or it can be a logic module or software that can implement some or all of the functions of the terminal or network device.

[0259] A communication device provided in this application is shown in FIG13 , where the communication device 1300 includes a transceiver unit 1310 and a processing unit 1320 .

[0260] One possible design is that the communication device 1300 is used to implement the functions of the terminal in the method embodiments shown in Figures 6, 9, and 10 above.

[0261] Among them, the transceiver unit 1310 is used to receive a first reference signal and send first uplink channel state information, where the first uplink channel state information is obtained by performing RF channel reciprocity compensation on the first downlink channel state information, and the first downlink channel state information is obtained based on the first reference signal.

[0262] Optionally, the transceiver unit 1310 is further configured to send first downlink channel state information, where the first downlink channel state information and the first uplink channel state information are carried in the same message.

[0263] Optionally, the processing unit 1320 is configured to perform radio frequency channel reciprocity compensation (or reverse calculation) on the first downlink channel state information according to a reciprocity calibration result of the radio frequency channel of the terminal to obtain the first uplink channel state information.

[0264] Optionally, the transceiver unit 1310 is further configured to receive first information, where the first information is used to instruct to report downlink channel state information and uplink channel state information.

[0265] Optionally, the transceiver unit 1310 is further configured to send second information, where the second information is used to indicate the capability of reporting downlink channel state information and uplink channel state information.

[0266] Optionally, the first uplink channel state information is associated with difference information between radio frequency channels corresponding to the first reference signal, and the difference information includes a delay difference and / or a phase difference.

[0267] Optionally, the reciprocity calibration result of the radio frequency channels of the terminal includes a delay difference and / or a phase difference between the radio frequency channels corresponding to the first reference signal.

[0268] Optionally, the processing unit 1320 is configured to perform reciprocity calibration on the radio frequency channel to obtain a delay difference and / or a phase difference.

[0269] Optionally, the transceiver unit 1310 is further configured to send a second reference signal and receive second uplink channel state information, where the second uplink channel state information is obtained based on the second reference signal.

[0270] The transceiver unit 1310 is further configured to receive a third reference signal. The processing unit 1320 is further configured to determine a delay difference and / or a phase difference based on the second uplink channel state information and the second downlink channel state information, wherein the second downlink channel state information is obtained based on the third reference signal.

[0271] The transceiver unit 1310 may perform reciprocity calibration on the radio frequency channel corresponding to the first reference signal according to the second uplink channel state information and the second downlink channel state information to determine the delay difference and / or the phase difference.

[0272] A more detailed description of the transceiver unit 1310 and the processing unit 1320 can be directly obtained by referring to the relevant description in the above method embodiment, and will not be repeated here.

[0273] Another possible design is that the communication device 1300 is used to implement the functions of the network device in the method embodiments shown in Figures 6 and 10 above.

[0274] The transceiver unit 1310 is configured to send a first reference signal and receive first uplink channel state information, where the first uplink channel state information is obtained by performing radio frequency channel reciprocity compensation on the first downlink channel state information, and the first downlink channel state information is obtained based on the first reference signal.

[0275] Optionally, the transceiver unit 1310 is further configured to receive first downlink channel state information, where the first downlink channel state information and the first uplink channel state information are carried in the same message.

[0276] Optionally, the transceiver unit 1310 is further configured to send first information, where the first information is used to indicate reporting of downlink channel state information and uplink channel state information.

[0277] Optionally, the transceiver unit 1310 is further configured to receive second information, where the second information is used to indicate the capability of reporting downlink channel state information and uplink channel state information.

[0278] Optionally, the first uplink channel state information is associated with difference information between radio frequency channels corresponding to the first reference signal, and the difference information includes a delay difference and / or a phase difference.

[0279] Optionally, the transceiver unit 1310 is further configured to receive a second reference signal and transmit second uplink channel state information, where the second uplink channel state information is obtained based on the second reference signal. The processing unit 1320 is configured to measure the uplink channel based on the second reference signal to obtain the second uplink channel state information.

[0280] The transceiver unit 1310 is further configured to transmit a third reference signal, which is used to determine the second downlink channel state information. The delay difference and / or phase difference is obtained based on the second uplink channel state information and the second downlink channel state information. In other words, the second uplink channel state information and the second downlink channel state information are used by the terminal to perform reciprocity calibration on the radio frequency channels corresponding to the first reference signal to obtain the delay difference and / or phase difference between the radio frequency channels corresponding to the first reference signal.

[0281] A more detailed description of the transceiver unit 1310 and the processing unit 1320 can be directly obtained by referring to the relevant description in the above method embodiment, and will not be repeated here.

[0282] It should be noted that the transceiver unit may also be referred to as a transceiver module, transceiver, transceiver, or transceiver device. The processing unit may also be referred to as a processor, processing board, processing module, or processing device. Optionally, the transceiver unit is used to perform the sending and receiving operations on the terminal or network device side in the above method. The device used to implement the receiving function in the communication module can be considered the receiving unit, and the device used to implement the sending function in the communication module can be considered the sending unit. That is, the transceiver unit includes the receiving unit and the sending unit.

[0283] It should also be noted that, in one possible design, the aforementioned transceiver unit and / or processing unit may be implemented through a virtual module. For example, the processing unit may be implemented through a software function unit or a virtual device, and the transceiver unit may be implemented through a software function or a virtual device. In another possible design, the processing unit or the transceiver unit may also be implemented through a physical device. For example, if the device is implemented using a chip / chip circuit, the transceiver unit may be an input / output circuit and / or a communication interface that performs input operations (corresponding to the aforementioned receiving operations) and output operations (corresponding to the aforementioned sending operations); the processing unit is an integrated processor or microprocessor or integrated circuit.

[0284] The division of units in the embodiments of the present application is schematic and is merely a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various examples of the embodiments of the present application may be integrated into a single processor, or may exist physically separately, or two or more modules may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or software functional modules.

[0285] Another communication device provided by the present application is shown in FIG14 , where the communication device 1400 includes a processor 1410. The processor 1410 can be used to execute computer programs or instructions in a memory to implement the steps performed by the terminal or the steps performed by the network device in the above method embodiment.

[0286] Optionally, the apparatus 1400 further includes a communication interface 1420. The processor 1410 and the communication interface 1420 are coupled to each other. It is understood that the communication interface 1420 may be a transceiver or an input / output interface.

[0287] Optionally, the communication device 1400 may further include a memory 1430 for storing instructions executed by the processor 1410 or storing input data required by the processor 1410 to run instructions or storing data generated after the processor 1410 runs instructions.

[0288] When the communication device 1400 is used to implement the method in the above embodiment, the processor 1410 is used to perform the functions of the above processing unit, and the communication interface 1420 is used to perform the functions of the above receiving unit and / or sending unit. Whether the communication interface 1420 is used for sending or receiving can be determined by whether it is used to perform sending or receiving actions in the solution implemented by the communication device 1400.

[0289] When the communication device 1400 is a chip used in a terminal, the chip implements the functions of the terminal in the above method embodiments. The chip of the terminal receives signals from other modules in the terminal (such as a radio frequency module or antenna), and the signals may be sent to the terminal by a network device; or the chip of the terminal sends signals to other modules in the terminal (such as a radio frequency module or antenna), and the signals may be sent to the network device by the terminal.

[0290] When the communication device 1400 is a chip used in a network device, the chip implements the functions of the network device in the above method embodiments. The chip of the network device receives signals from other modules in the network device (such as a radio frequency module or antenna), and the signals may be sent by the terminal to the network device; or the chip of the network device sends signals to other modules in the network device (such as a radio frequency module or antenna), and the signals may be sent by the network device to the terminal.

[0291] It is understood that when the communication device 1400 is a terminal or network device, the communication interface 1420 may be a transceiver, specifically including a transmitter and a receiver, where the transmitter is used to transmit signals and the receiver is used to receive signals. When the communication device 1400 is a chip used in a terminal or network device, the communication interface 1420 may be an input / output circuit, a bus, a module, a pin, or other type of communication interface, where the input circuit of the input / output circuit can be used for receiving, and the output interface can be used for transmitting.

[0292] It should be understood that in the communication device 1400 shown in FIG. 14 , the processor 1410 may correspond to the processing unit 1110 in the above communication device 1100 , and the communication interface 1420 may correspond to the transceiver unit 1140 in the above communication device 1100 .

[0293] It should also be understood that the coupling in the embodiments of the present application is an indirect coupling or communication connection between devices, units, or modules, which can be electrical, mechanical, or other forms, and is used for information exchange between devices, units, or modules. The processor 1410 may operate in conjunction with the memory 1430. The specific connection medium between the processor 1410, communication interface 1420, and memory 1430 is not limited in the embodiments of the present application.

[0294] Optionally, the processor 1410, the communication interface 1420, and the memory 1430 are interconnected via a bus. The bus may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus. The bus may be divided into an address bus, a data bus, a control bus, and the like.

[0295] Figure 15 is a schematic diagram of the structure of the terminal provided in an embodiment of the present application. As shown in Figure 15, the terminal 1500 can perform the functions of the terminal in the above-mentioned method embodiment. As shown in the figure, the terminal 1500 includes a processor 1501 and a transceiver 1502. Optionally, the terminal 1500 also includes a memory 1503. Among them, the processor 1501, the transceiver 1502 and the memory 1503 can communicate with each other through an internal connection path to transmit control and / or data signals. The memory 1503 is used to store computer programs, and the processor 1501 is used to call and run the computer program from the memory 1503 to control the transceiver 1502 to send and receive signals. Optionally, the terminal 1500 may also include an antenna 1504 for sending the uplink data or uplink control signaling output by the transceiver 1502 through a wireless signal.

[0296] The processor 1501 and the memory 1503 may be combined into a processing device, and the processor 1501 is configured to execute program code stored in the memory 1503 to implement the aforementioned functions. In a specific implementation, the memory 1503 may also be integrated into the processor 1501 or independent of the processor 1501. The processor 1501 may correspond to the processing unit in FIG. 11 or the processor in FIG. 12 .

[0297] The transceiver 1502 may correspond to the transceiver unit in FIG. 11 or the communication interface in FIG. 12 , and may also be referred to as a transceiver unit. The transceiver 1502 may include a receiver (or receiver, receiving circuit) and a transmitter (or transmitter, transmitting circuit). The receiver is used to receive signals, and the transmitter is used to transmit signals.

[0298] It should be understood that terminal 1500 shown in FIG15 is capable of implementing the various processes involved in the terminal in the aforementioned method embodiments. The operations and / or functions of the various modules in terminal 1500 are respectively for implementing the corresponding processes in the aforementioned method embodiments. For details, please refer to the description of the aforementioned method embodiments; to avoid repetition, detailed descriptions are omitted here.

[0299] The processor 1501 can be used to execute the actions implemented by the terminal as described in the previous method embodiments, and the transceiver 1502 can be used to execute the actions of the terminal sending to or receiving from the network device as described in the previous method embodiments. For details, please refer to the description of the previous method embodiments, which will not be repeated here.

[0300] Optionally, the terminal 1500 may further include a power supply 1505 for providing power to various devices or circuits within the terminal. In this embodiment of the present application, a rectifier may be connected between the power supply 1505 and the antenna 1504. After the electromagnetic wave signal is received by the antenna 1504 and converted into an alternating current signal, it may be further converted into a direct current signal by the rectifier and then output to the power supply 1505.

[0301] In addition, in order to make the functions of the terminal more complete, the terminal 1500 can also include one or more of an input unit 1506, a display unit 1507, an audio circuit 1508, a camera 1509 and a sensor 1510, and the audio circuit can also include a speaker 1508a, a microphone 1508b, etc.

[0302] Figure 16 is a schematic diagram of the structure of a network device provided in an embodiment of the present application. The network device 1600 shown in Figure 16 can perform the functions of the network device in the above-described method embodiment. As shown in the figure, base station 1600 may include one or more of the following: one or more antennas 1610, at least one processor 1611, and at least one memory 1612.

[0303] The processor 1611 can be used to execute the steps performed by the network device in the above method embodiment to implement the communication method of the embodiment of the present application.

[0304] It should be understood that network device 1600 shown in FIG16 is capable of implementing each process related to the network device in the above-described method embodiment. The operations and / or functions of each module in network device 1600 are respectively for implementing the corresponding processes in the above-described method embodiment. For details, please refer to the description of the above-described method embodiment; to avoid repetition, detailed descriptions are omitted here.

[0305] It is understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0306] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0307] The present application also provides a communication system, which includes the aforementioned network device and terminal.

[0308] The present application also provides a computer program product, which includes: a computer program (also referred to as code, or instructions), which, when executed, enables a computer to execute the method executed by a terminal or the method executed by a network device in the above method embodiment.

[0309] The present application also provides a computer-readable storage medium storing a computer program (also referred to as code or instruction). When the computer program is executed, the computer executes the method executed by the terminal or the method executed by the network device in the above method embodiment.

[0310] The terms "unit," "module," and the like used in this specification may be used to refer to a computer-related entity, hardware, firmware, a combination of hardware and software, software, or software in execution.

[0311] Those skilled in the art will appreciate that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented using electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application. In the several embodiments provided in this application, it should be understood that the disclosed devices, equipment, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed can be through some interface, indirect coupling or communication connection of devices or units, and can be electrical, mechanical, or other forms.

[0312] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of the solution of this embodiment according to actual needs.

[0313] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0314] In the above embodiments, the functions of each functional unit can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions (programs). When the computer program instructions (program) are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0315] If this function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0316] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: Applied to a terminal, the method comprises: receiving a first reference signal; Sending first uplink channel state information, where the first uplink channel state information is obtained by performing radio frequency channel reciprocity compensation on first downlink channel state information, where the first downlink channel state information is obtained based on the first reference signal.

2. The method according to claim 1, characterized in that The method further comprises: The first downlink channel state information is sent, where the first downlink channel state information and the first uplink channel state information are carried in the same message.

3. The method according to claim 1 or 2, characterized in that: Before receiving the first reference signal, the method further includes: First information is received, where the first information is used to indicate reporting of downlink channel state information and uplink channel state information.

4. The method according to any one of claims 1 to 3, characterized in that The method further comprises: Sending second information, where the second information is used to indicate the capability of reporting downlink channel state information and uplink channel state information.

5. The method according to any one of claims 1 to 4, characterized in that The first uplink channel state information is associated with difference information between radio frequency channels corresponding to the first reference signal, and the difference information includes a delay difference and / or a phase difference.

6. The method according to claim 5, characterized in that The method further comprises: Reciprocity calibration is performed on the radio frequency channel to obtain the delay difference and / or the phase difference.

7. The method according to claim 5, characterized in that The method further comprises: sending a second reference signal; receiving second uplink channel state information, where the second uplink channel state information is obtained based on the second reference signal; receiving a third reference signal; The delay difference and / or the phase difference is determined according to the second uplink channel state information and the second downlink channel state information, wherein the second downlink channel state information is obtained based on the third reference signal.

8. A communication method, characterized in that: Applied to a network device, the method comprises: sending a first reference signal; First uplink channel state information is received, where the first uplink channel state information is obtained by performing radio frequency channel reciprocity compensation on first downlink channel state information, where the first downlink channel state information is obtained based on the first reference signal.

9. The method according to claim 8, characterized in that The method further comprises: The first downlink channel state information is received, where the first downlink channel state information and the first uplink channel state information are carried in the same message.

10. The method according to claim 8 or 9, characterized in that: Before sending the first reference signal, the method further includes: First information is sent, where the first information is used to indicate reporting of downlink channel state information and uplink channel state information.

11. The method according to any one of claims 8 to 10, characterized in that: The method further comprises: Second information is received, where the second information is used to indicate the capability of reporting downlink channel state information and uplink channel state information.

12. The method according to any one of claims 8 to 11, characterized in that The first uplink channel state information is associated with difference information between radio frequency channels corresponding to the first reference signal, and the difference information includes a delay difference and / or a phase difference.

13. The method according to claim 12, characterized in that The method further comprises: receiving a second reference signal; Sending second uplink channel state information, where the second uplink channel state information is obtained based on the second reference signal; A third reference signal is sent, where the third reference signal is used to determine second downlink channel state information, and the delay difference and / or phase difference is obtained based on the second uplink channel state information and the second downlink channel state information.

14. A communication device, characterized in that: It includes a processor and a communication interface, wherein the communication interface is used to receive signals from other communication devices outside the communication device and transmit them to the processor or send signals from the processor to other communication devices outside the communication device, and the processor is used to implement the method as described in any one of claims 1 to 7 through logic circuits or execute code instructions, or to implement the method as described in any one of claims 8 to 13.

15. A communication system, characterized in that: The invention comprises a communication device for implementing the method according to any one of claims 1 to 7, and a communication device for implementing the method according to any one of claims 8 to 13.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is executed, or the method according to any one of claims 8 to 13 is executed.

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