Random access method and communication device

Abstract

The invention provides a random access method and a communication device, which can avoid using the GNSS capability of a terminal device to perform random access, so that the success rate of random access can be improved under the condition that the terminal device without the GNSS capability performs random access, and the random access method and the communication device can be applied to a communication system. The method comprises: a terminal device receiving first indication information from a network device; wherein the first indication information is used for indicating a first corresponding relation between a first service area of the network equipment and at least one first time advance. The first service area is a service area where the terminal device is located. Therefore, the terminal device can send the first message to the network equipment according to the at least one first time advance so as to carry out random access.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a random access method and a communication device. Background Art

[0002] In a non-terrestrial network (NTN), the network equipment can indicate the location of a reference point to the terminal device, and the network equipment can also indicate the ephemeris information of the satellite to the terminal device. The terminal device determines its own position based on the global navigation satellite system (GNSS) capability, and determines the time advance in combination with its own position and the position of the reference point. In the process of random access by the terminal device, the terminal device can send a message to the network device according to the time advance, thereby performing random access. However, when the terminal device does not have GNSS capability, or when the terminal device cannot determine the time advance in combination with its own position, the success rate of random access will be reduced. Therefore, a method to solve this problem is urgently needed. Summary of the invention

[0003] The embodiments of the present application provide a random access method and a communication device, which can improve the success rate of random access when a terminal device without GNSS capability randomly accesses, or when the terminal device cannot determine the time advance based on its own position.

[0004] In order to achieve the above purpose, this application adopts the following technical solutions:

[0005] In a first aspect, a random access method is provided. Optionally, the execution subject of the method may be a terminal device, or a device in the terminal device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the functions of the terminal device. The following description is given by taking a terminal device as an example. The random access method includes: the terminal device receives a first indication information from a network device. The first indication information is used to indicate a first correspondence between a first service area of ​​the network device and at least one first time advance. The first service area is the service area where the terminal device is located. The terminal device sends a message one to the network device according to at least one first time advance. Message one is used for random access.

[0006] Based on the random access method provided by the first aspect, the terminal device can obtain at least one first time advance within the first service area where the terminal device is located from the network equipment, and send message one based on the at least one first time advance, thereby realizing time pre-compensation of message one, so that on the network equipment side, the message one sent by the terminal device can be aligned with the message one sent by other terminal devices. In this way, in the case of random access by a terminal device without GNSS capability, the random access success rate can be improved.

[0007] In one possible design, at least one first time advance is related to at least one distance. The at least one distance is a distance between at least one first position in the first service area and the network device. In this way, the at least one first time advance can be matched with the network device and at least one first position in the first service area, further improving the success rate of random access.

[0008] Optionally, one of the at least one first position may be: a position farthest from the network device in the first service area, or a position closest to the network device in the first service area, or a central position of the first service area.

[0009] In a possible design scheme, the first indication information can also be used to indicate a second correspondence between different global satellite navigation system GNSS capabilities and the cyclic prefix CP length of the random access preamble. Message one includes a random access preamble, and the CP length of the random access preamble in message one is determined according to the GNSS capability of the terminal device and the second correspondence. In this way, the length of the cyclic prefix of the random access preamble used for the terminal device can be matched with the GNSS capability of the terminal device, so that when the terminal device has no GNSS capability, the success rate of the terminal device's random access to the network device can be further improved on the basis of at least one first time advance indicated by the network device.

[0010] Optionally, in the second corresponding relationship, the CP length of the random access preamble corresponding to the non-GNSS capability is greater than the CP length of the random access preamble corresponding to the GNSS capability. In this way, the CP length of the random access preamble used by the terminal device without GNSS capability can be longer than the CP length of the random access preamble used by the terminal device with GNSS capability, so that when the first service area is large, the random access preambles of the terminal devices in the first service area can still be aligned on the network device side, thereby improving the success rate of random access.

[0011] In a possible design scheme, the method provided in the first aspect may further include: the terminal device receives message two from the network device. Message two is used to indicate the time-frequency resources carrying message three. The terminal device sends message three to the network device according to the time-frequency resources indicated by message two. Message three includes identification information of the terminal device. The terminal device receives message four from the network device. Message four is used to indicate that the terminal device successfully resolves the contention. In this way, the random access process can be completed.

[0012] Optionally, the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access. Message two includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying message three. The time-frequency resources carrying message three are the time-frequency resources in the time-frequency resource set for random access corresponding to the GNSS capability of the terminal device. In this way, the correspondence between different GNSS capabilities and the time-frequency resource set for random access can be indicated by the first indication information, and the time-frequency resources used to carry message three can be determined from the time-frequency resource set for random access that does not correspond to the GNSS capability.

[0013] Optionally, the terminal device receiving the second message from the network device may include: the terminal device receiving the second message from the network device after the first moment. The time length between the end moment of sending the first message by the terminal device and the first moment is the first time length. The first time length is twice the first time advance. That is, after sending the first message, the terminal device may wait for twice the first time advance and then open the monitoring window to monitor the second message, so that the time for monitoring the second message can be reduced, thereby reducing the power consumption of the terminal device.

[0014] Optionally, the terminal device receiving message 4 from the network device may include: the terminal device receiving message 4 from the network device after the second moment. The time length between the end moment of sending message 3 by the terminal device and the second moment is the second time length. The second time length is twice the first time advance. That is, after sending message 3, the terminal device may wait for twice the first time advance and then open the monitoring window to monitor message 4, so that the time for monitoring message 4 can be reduced, thereby reducing the power consumption of the terminal device.

[0015] In one possible design, the terminal device is a terminal device without GNSS capability, and the network device is a satellite.

[0016] In a second aspect, a random access method is provided. Optionally, the execution subject of the method may be a network device, or a device in the network device (such as a processor, a chip, or a chip system, etc.), or a logic module or software that can implement all or part of the network device functions. The random access method includes: the network device sends a first indication message to the terminal device. The first indication information is used to indicate a first correspondence between a first service area of ​​the network device and at least one first time advance. The first service area is the service area where the terminal device is located. The network device receives message one from the terminal device. Message one is sent by the terminal device according to at least one first time advance, and message one is used for random access.

[0017] Based on the random access method provided in the second aspect, the network equipment can configure at least one first time advance corresponding to the first service area where the terminal device is located for the terminal device, so that the terminal device can send message one based on the at least one first time advance to achieve time pre-compensation of message one, so that message one can be aligned with message one of other terminal devices on the network device side, thereby improving the success rate of random access.

[0018] In one possible design, at least one first time advance is related to at least one distance. The at least one distance is a distance between at least one first position in the first service area and the network device. In this way, the at least one first time advance can be matched with the network device and at least one first position in the first service area, further improving the success rate of random access.

[0019] Optionally, one of the at least one first position may be: a position farthest from the network device in the first service area, or a position closest to the network device in the first service area, or a central position of the first service area.

[0020] In a possible design scheme, the first indication information can also be used to indicate a second correspondence between different global satellite navigation system GNSS capabilities and the cyclic prefix CP length of the random access preamble. The CP length of the random access preamble in message one is determined based on the GNSS capability of the terminal device and the second correspondence. In this way, the length of the cyclic prefix of the random access preamble used for the terminal device can be matched with the GNSS capability of the terminal device, so that when the terminal device has no GNSS capability, the success rate of the terminal device's random access to the network device can be further improved on the basis of the first time advance indicated by the network device.

[0021] Optionally, in the second corresponding relationship, the CP length of the random access preamble corresponding to the non-GNSS capability is greater than the CP length of the random access preamble corresponding to the GNSS capability. In this way, the CP length of the random access preamble used by the terminal device without GNSS capability can be longer than the CP length of the random access preamble used by the terminal device with GNSS capability, so that when the first service area is large, the random access preambles of the terminal devices in the first service area can still be aligned on the network device side, thereby improving the success rate of random access.

[0022] In a possible design, the network device receives a message 1 from the terminal device, which may include: the network device receives the message 1 from the terminal device within a first time period. The length of the first time period is related to the random access preamble carried by the message 1. In this way, the length of time the network device receives the message 1 can match the cyclic shift value of the random access preamble, so that the length of time the message is received matches the range of the first service area, thereby improving the detection success rate of the message 1, and further improving the random access success rate.

[0023] Optionally, the length of the first time period is positively correlated with the cyclic shift value of the leading sequence of the random access leading code carried by message 1. In this way, the message 1 can be received in a longer time when the range of the first service area is larger, thereby improving the detection success rate of the message 1 and further improving the random access success rate.

[0024] A possible design scheme, the method provided in the second aspect may also include: the network device sends message two to the terminal device. Message two is used to indicate the time-frequency resources carrying message three. The network device receives message three from the terminal device on the time-frequency resources. Message three includes identification information of the terminal device. The network device sends message four to the terminal device. Message four is used to indicate that the terminal device has successfully resolved the contention. In this way, the random access process can be completed.

[0025] Optionally, the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access. Message two includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying message three. The time-frequency resources carrying message three are the time-frequency resources in the time-frequency resource set for random access corresponding to the GNSS capability of the terminal device. In this way, the correspondence between different GNSS capabilities and the time-frequency resource set for random access can be indicated by the first indication information, and the time-frequency resources used to carry message three can be determined from the time-frequency resource set for random access that does not correspond to the GNSS capability.

[0026] In one possible design, the terminal device is a terminal device without GNSS capability, and the network device is a satellite.

[0027] In addition, the technical effects of the random access method described in the second aspect can refer to the technical effects of the random access method described in the first aspect, and will not be repeated here.

[0028] In a third aspect, a communication device is provided, wherein the communication device is used to execute the random access method described in any one of the implementations of the first aspect or the second aspect.

[0029] In the present application, the communication device described in the third aspect may be the terminal device described in the first aspect or the network device described in the second aspect, or a chip (system) or other parts or components that may be arranged in the terminal device or network device, or a device that includes the terminal device or network device.

[0030] It should be understood that the communication device described in the third aspect includes a module, unit, or means corresponding to the random access method described in any one of the first aspect or the second aspect, and the module, unit, or means can be implemented by hardware, software, or hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units for performing the functions involved in the random access method.

[0031] In a fourth aspect, a communication device is provided, including: a processor, configured to execute the random access method described in any possible implementation manner of the first aspect or the second aspect.

[0032] In a possible design solution, the communication device described in the fourth aspect may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver may be used for the communication device described in the fourth aspect to communicate with other communication devices.

[0033] In a possible design scheme, the communication device described in the fourth aspect may further include a memory. The memory may be integrated with the processor or may be separately provided. The memory may be used to store the computer program and / or data involved in the random access method described in any one of the first aspect or the second aspect.

[0034] In the present application, the communication device described in the fourth aspect may be the terminal device described in the first aspect or the network device described in the second aspect, or a chip (system) or other parts or components that may be arranged in the terminal device or network device, or a device that includes the terminal device or network device.

[0035] In a fifth aspect, a communication device is provided. The communication device includes: a processor, the processor is coupled to a memory, and the processor is used to execute a computer program stored in the memory, so that the communication device performs the random access method described in any possible implementation manner of the first aspect or the second aspect.

[0036] In a possible design solution, the communication device described in the fifth aspect may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver may be used for the communication device described in the fifth aspect to communicate with other communication devices.

[0037] In the present application, the communication device described in the fifth aspect may be the terminal device described in the first aspect or the network device described in the second aspect, or a chip (system) or other parts or components that may be arranged in the terminal device or network device, or a device that includes the terminal device or network device.

[0038] In a sixth aspect, a communication device is provided, comprising: a processor and a memory; the memory is used to store a computer program, and when the processor executes the computer program, the communication device executes the random access method described in any one of the implementation methods in the first aspect or the second aspect.

[0039] In a possible design solution, the communication device described in the sixth aspect may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver may be used for the communication device described in the sixth aspect to communicate with other communication devices.

[0040] In the present application, the communication device described in the sixth aspect may be the terminal device described in the first aspect or the network device described in the second aspect, or a chip (system) or other parts or components that may be arranged in the terminal device or network device, or a device that includes the terminal device or network device.

[0041] In the seventh aspect, a communication device is provided, comprising: a processor; the processor is used to couple with a memory, and after reading a computer program in the memory, execute the random access method as described in any one of the implementation methods in the first aspect or the second aspect according to the computer program.

[0042] In a possible design solution, the communication device described in the seventh aspect may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver may be used for the communication device described in the seventh aspect to communicate with other communication devices.

[0043] In the present application, the communication device described in the seventh aspect may be the terminal device described in the first aspect or the network device described in the second aspect, or a chip (system) or other parts or components that may be arranged in the terminal device or network device, or a device that includes the terminal device or network device.

[0044] In an eighth aspect, a processor is provided, wherein the processor is configured to execute the random access method described in any possible implementation manner in the first aspect or the second aspect.

[0045] In a ninth aspect, a communication system is provided, wherein the communication system comprises one or more terminal devices and one or more network devices.

[0046] In the tenth aspect, a computer-readable storage medium is provided, comprising: a computer program or instructions; when the computer program or instructions are executed on a computer, the computer executes the random access method described in any possible implementation of the first aspect or the second aspect.

[0047] In the eleventh aspect, a computer program product is provided, comprising a computer program or instructions, which, when executed on a computer, enables the computer to execute the random access method described in any possible implementation of the first aspect or the second aspect.

[0048] In addition, the technical effects of the communication device described in the third to eleventh aspects above can refer to the technical effects of the random access method described in the first or second aspects above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic diagram of the initial access process provided in an embodiment of the present application;

[0050] Figure 2 A schematic diagram of a random access process in a terrestrial network provided in an embodiment of the present application;

[0051] Figure 3 A schematic diagram of a random access process in a non-terrestrial network provided in an embodiment of the present application;

[0052] Figure 4 A schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0053] Figure 5 A schematic diagram of a random access method provided in an embodiment of the present application;

[0054] Figure 6 A schematic diagram of a flow chart of another random access method provided in an embodiment of the present application;

[0055] Figure 7A schematic diagram of a flow chart of another random access method provided in an embodiment of the present application;

[0056] Figure 8 A schematic diagram of a flow chart of another random access method provided in an embodiment of the present application;

[0057] Fig. 9 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0058] Fig.10 A schematic diagram of the structure of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0059] The following first introduces the technical terms and related technologies involved in the embodiments of the present application.

[0060] 1. Timing advance (TA) refers to the parameter used to coordinate the time slot synchronization between network devices, such as access network devices and terminal devices in mobile communication systems, to ensure that the terminal devices send or receive data at the correct time to maintain the reliability of communication. For example, if the terminal device sends an uplink signal to the network device and hopes that the uplink signal will arrive at the network device at time T1, and the transmission delay between the terminal device and the network device is TA1, then the terminal device can send the uplink signal at time T1-TA1.

[0061] 2. In non-terrestrial networks (NTN), services can be provided to terminal devices through satellites or unmanned aerial systems (UAS) (including high altitude platform stations (HAPS)). The coverage of network equipment in non-terrestrial networks is larger than that of network equipment in terrestrial networks. Taking the satellite as an example, the higher the orbit of the satellite, the larger the coverage area of ​​the satellite.

[0062] The orbits of satellites can be divided into low-earth orbit (LEO), medium-earth orbit (MEO) and geostationary earth orbit (GEO) according to their altitude. Among them, the orbit altitude of LEO is 300 kilometers (kilometre, km) to 2000km. The orbit altitude of MEO is 7000km to 25000km, and the orbit altitude of GEO is 35786km. The relative position of satellites operating on GEO and the earth is not affected by the rotation of the earth. Non-geosynchronous orbits (NGSO) include low earth orbits with altitudes of about 300km to 1500km and medium earth orbits with altitudes of about 7000km to 25000km. The corresponding relationship between the orbit altitudes and beams of satellites in different orbits is shown in Table 1 below.

[0063] Table 1

[0064]

[0065] In a cellular network, a terminal device can access the network through an initial access process. The process of initial access by the terminal device is as follows: Figure 1 The initial access process includes:

[0066] S101, the terminal device searches for a cell and selects a cell.

[0067] The implementation of S101 may refer to the principles of cell search and cell selection in the prior art, which will not be described in detail here.

[0068] S102, the terminal device randomly accesses the selected cell.

[0069] After the terminal device selects a cell and resides in the selected cell, it initiates a random access process in the cell where it resides. Through the random access process, the terminal device can achieve uplink synchronization with the cell and obtain the uplink transmission time advance. In addition, when the terminal device establishes the initial wireless link, that is, when the terminal device switches from the idle state to the connected state (active), it can obtain the user identity, such as the cell radio network temporary identifier (C-RNTI), through the random access process.

[0070] The implementation principle of S102 can be referred to as follows Figure 2 The random access procedure provided.

[0071] S103, a radio resource control (RRC) link is established between the terminal device and the first network equipment.

[0072] The implementation principle of S103 may refer to the principle of establishing an RRC connection in the prior art, which will not be described in detail here.

[0073] S104, the terminal device establishes an initial context.

[0074] The terminal device may interact with the first network device and the second network device to establish an initial context. The second network device may include a core network element, or a device that implements the function of a core network element.

[0075] The implementation principle of S104 may refer to the principle of establishing an initial context in the prior art, which will not be described in detail here.

[0076] S105, the terminal device establishes a protocol data unit (PDU) session connection.

[0077] The implementation principle of S105 may refer to the principle of establishing a PDU session connection in the prior art, which will not be described in detail here.

[0078] In the communication system based on the ground network, the first network device may be a wireless access network device. In this case, the process of random access by the terminal device is as follows: Figure 2 shown. Figure 2 The random access procedure shown includes:

[0079] S201, the terminal device sends a message 1 to the first network device. Correspondingly, the first network device receives the message 1 from the terminal device.

[0080] Among them, message one carries a random access (RA) preamble, which can be used to estimate the uplink time difference between the terminal device and the first network device. In other words, the random access preamble can be used for the terminal device to access the first network device. Message one can also be called message 1 (message 1, Msg1), or the first message.

[0081] After sending the message 1, the terminal device may start a first timer, and the timing duration of the first timer may be timing duration #1. For example, timing duration #1 may be the duration of ra-ResponseWindow.

[0082] S202, the first network device sends a second message to the terminal device. Correspondingly, the terminal device receives the second message from the first network device.

[0083] The second message includes an uplink time difference from the terminal device to the first network device, and the uplink time difference is determined by the first network device according to the received random access preamble code.

[0084] Message 2 may be carried on a physical downlink shared channel (PDSCH). It is understood that the same PDSCH may carry RARs corresponding to multiple terminal devices. Message 2 may also be referred to as a random access response (RAR), message 2 (Msg2), or a second message.

[0085] After receiving the message 1, the terminal device can monitor and receive the message 2 from the network device within the timing duration #1 after starting the first timer.

[0086] After receiving the second message from the first network device, the terminal device can close the first timer, or in other words, stop the first timer, so that the monitoring time of the terminal device can be reduced, thereby reducing the overhead.

[0087] S203, the terminal device sends message 3 to the first network device according to message 2. Correspondingly, the first network device receives message 3 from the terminal device.

[0088] Message three may also be referred to as message 3 (Msg3), or the third message.

[0089] It is understandable that the terminal device may start the second timer after sending the completion message 3, and the timing duration of the second timer may be timing duration #2. For example, timing duration #2 may be the duration of ra-ContentionResolutionTimer.

[0090] After receiving the message three, the first network device may execute the following S204.

[0091] S204, the first network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the first network device.

[0092] It is understandable that the terminal device can monitor and receive message four from the first network device within the timing duration #2 after the second timer is started.

[0093] After receiving the message 4 from the first network device, the terminal device can close the second timer, or in other words, stop the second timer. In this way, the monitoring time of the terminal device can be reduced, thereby reducing the overhead.

[0094] After receiving the message 4, the terminal device determines that the random access is successful. At this time, data can be transmitted between the terminal device and the first network device.

[0095] Message four may also be referred to as message 4 (Msg4), or the fourth message, or a contention resolution message.

[0096] exist Figure 2 In the provided process, in the process of random access of the terminal, the uplink time-frequency resources in the same cell are orthogonal, so the uplink transmissions of different terminals in the same cell will not interfere with each other.

[0097] In order to maintain this uplink orthogonality, given a set of parameters (Numerology), such as the subcarrier spacing type, the uplink subframe boundaries in the same cell are required to be (approximately) aligned on the first network device side. In other words, the time misalignment of the received signal should fall within the cyclic prefix (CP). In order to ensure the time alignment of the received signal on the first network device, the new radio (NR) standard introduces the TA mechanism. TA is used for uplink transmission of terminal devices, which means that the subframe in which the terminal device sends uplink data must be advanced by a certain time compared to the corresponding uplink subframe. The specific advance amount is calculated by the gNodeB based on the RA preamble (random access preamble) sent by the UE, and then notified to the terminal device through a timing advance command (TAC). The terminal device adjusts the sending time of the uplink signal according to the received TA to achieve uplink synchronization between the terminal device and the gNodeB.

[0098] In a communication system based on a non-terrestrial network, such as a satellite communication system, the first network device is far away from the ground coverage area and has a large delay. On the other hand, the coverage range of the first network device is much larger than the coverage range of the first network device in the terrestrial network. The cyclic prefix of the existing random access preamble code cannot meet the alignment requirements, which will cause the random access failure of the terminal device.

[0099] In order to solve the problem of random access of terminal devices in non-terrestrial networks, the terminal devices may perform time pre-compensation when sending random access preamble codes.

[0100] The following takes a non-terrestrial network communication system as an example to explain the process of random access of a terminal device in a non-terrestrial network. Figure 3 As shown, the communication system of the non-terrestrial network includes a terminal device and a first network device, wherein the first network device may be a device having a wireless access device function, such as a satellite or an unmanned aerial vehicle. The terminal device is communicatively connected to the first network device, and the first network device is communicatively connected to the second network device via a terrestrial gateway. The second network device may include a core network element, or a device that implements the function of a core network element.

[0101] exist Figure 3 In the communication system shown in FIG. 1 , the process of random access of a terminal device is as follows: Figure 3 The random access process includes:

[0102] S301, the first network device sends information #1 to the terminal device. Correspondingly, the terminal device receives the information #1 from the first network device.

[0103] Among them, information #1 is used to indicate the location of the reference point of the link between the terminal device and the ground gateway.

[0104] In a possible design scheme, the position of the reference point may be the position of the satellite, in which case the position of the reference point may be determined based on the satellite's ephemeris information. The satellite's ephemeris information includes one or more of the following: the satellite's semi-major axis (semi-major axis)), eccentricity (Eccentricity (eccentricity)), orbital inclination (Inclination angle at reference time (inclination)), ascending node right ascension (Longitude of ascending node of orbit plane (right ascension of the ascending node)), perigee argument (Argument of periapsis)), mean anomaly (Mean anomaly at reference time (true anomaly and a reference point in time)) and reference time (Ephemeris reference time (the epoch)). It is understandable that the position of the reference point may also be a position on a feeder link or a service link, which will not be described in detail here.

[0105] It is understandable that information #1 can be carried in a broadcast message.

[0106] S302, the terminal device determines the timing advance according to information #1 and the location of the terminal device.

[0107] The terminal device determines the position of the satellite based on the satellite ephemeris information in information #1, and determines its own position based on the terminal device's own GNSS. The terminal device determines the timing advance based on the satellite's position and its own position.

[0108] Regarding the implementation principle of the terminal device determining the time advance amount according to the position of the satellite and its own position, reference can be made to the existing technology and will not be repeated here.

[0109] S303, the terminal device sends message 1 to the first network device according to the timing advance. Correspondingly, the first network device receives message 1 from the terminal device.

[0110] For the implementation principle of message one, please refer to the relevant introduction of S201, which will not be repeated here.

[0111] S304, the first network device sends message 2 to the terminal device. Correspondingly, the terminal device receives message 2 from the first network device.

[0112] For the implementation principle of message 2, please refer to the relevant introduction of message 2 in S202 above. For the implementation principle of S304, please refer to the relevant introduction of S202 above, which will not be repeated here.

[0113] S305, the terminal device sends message 3 to the first network device. Correspondingly, the first network device receives message 3 from the terminal device.

[0114] For the implementation principle of message three, please refer to the relevant introduction in S203.

[0115] For the implementation principle of message 2, please refer to the relevant introduction of message 2 in S203 above. For the implementation principle of S305, please refer to the relevant introduction of S203 above, which will not be repeated here.

[0116] S306, the first network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the first network device.

[0117] For the implementation principle of message 4, please refer to the relevant introduction in S204, and for the implementation principle of S306, please refer to the relevant introduction in S204, which will not be repeated here.

[0118] However, in a non-terrestrial network, when the terminal device does not have GNSS capability, the terminal device cannot obtain its own position, and therefore cannot accurately calculate the specific time advance amount based on the distance from the first network device, such as a satellite, and cannot achieve pre-compensation of the time advance amount. Due to the large distance difference between the terminal device and the first network device, the time delay difference when the message arrives at the first network device is large, and it cannot be aligned within the preset time window, which will cause random access failure.

[0119] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0120] The technical solution of the present application can be applied to satellite communication systems, high altitude platform station (HAPS) communications, drones and other non-terrestrial network (NTN) systems, for example, integrated communication and navigation (IcaN) systems, global navigation satellite systems (GNSS) and ultra-dense low-orbit satellite communication systems. Satellite communication systems can be integrated with traditional mobile communication systems. For example: the mobile communication system can be a fourth generation (4G) communication system (for example, a long term evolution (LTE) system), a worldwide interoperability for microwave access (WiMAX) communication system, a fifth generation (5G) communication system (for example, a new radio (NR) system), and future mobile communication systems, such as a sixth generation (6G) mobile communication system.

[0121] The technical solutions of the embodiments of the present application can be applied to various communication systems, such as wireless fidelity (WiFi) systems, vehicle to everything (V2X) communication systems, device-to-device (D2D) communication systems, Internet of Vehicles communication systems, 4th generation (4G) mobile communication systems, such as long term evolution (LTE) systems, worldwide interoperability for microwave access (WiMAX) communication systems, fifth generation (5G) mobile communication systems, such as new radio (NR) systems, and future communication systems, such as sixth generation (6G) mobile communication systems.

[0122] The present application will present various aspects, embodiments or features around a system that may include multiple devices, components, modules, etc. It should be understood and appreciated that each system may include additional devices, components, modules, etc., and / or may not include all of the devices, components, modules, etc. discussed in conjunction with the figures. In addition, combinations of these schemes may also be used.

[0123] In addition, in the embodiments of the present application, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present concepts in a concrete way.

[0124] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable in appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, the process, method, system, product or equipment comprising a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0125] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to 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 represent: 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. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c; a and b; a and c; b and c; or a and b and c. Among them, a, b, c can be single or multiple.

[0126] In the embodiments of the present application, sometimes a subscript such as W1 may be mistakenly written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are consistent.

[0127] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person of ordinary skill in the art can appreciate that with the evolution of the network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0128] To facilitate understanding of the embodiments of the present application, first Figure 4 The communication system shown in the example is used to describe in detail the communication system applicable to the embodiment of the present application. Figure 4 A schematic diagram of the architecture of a communication system applicable to the random access method provided in an embodiment of the present application.

[0129] like Figure 4 As shown, the communication system includes a network device 401 and terminal devices (terminal devices 402a to 402c).

[0130] The network device 401 and the terminal devices (terminal devices 402a to 402c) may exchange information.

[0131] Understandable, Figure 4 The communication system shown may also include a ground gateway 403. The network device 401 and the ground gateway 403 may exchange information.

[0132] The network device is located at the network side of the communication system and has a wireless transceiver function or is a chip or chip system that can be set in the device. The network device includes, but is not limited to: an access point (AP) in a wireless fidelity (WiFi) system, such as a home gateway, a router, a server, a switch, a bridge, etc., an evolved Node B (eNB), a radio network controller (RNC), a Node B (NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (e.g., home evolved NodeB, or homeNode B, HNB), a baseband unit (BBU), a wireless relay node, a wireless backhaul node, a transmission point (TRP or TP), etc., and can also be 5G, such as a gNB in ​​a new radio (NR) system, or a transmission point (TRP or TP), one or a group of (including multiple antenna panels) antenna panels of a base station in a 5G system, or a network node constituting a gNB or a transmission point, such as a baseband unit (BBU), or a distributed unit (DBU). unit (DU), road side unit (RSU) with base station function, etc.

[0133] The above-mentioned ground gateway is a terminal that accesses the above-mentioned communication system and has a wireless transceiver function or a chip or chip system that can be set in the terminal. The terminal device can also be called an access terminal, a user unit, a user station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent or a user device. The terminal device in the embodiment of the present application can be a mobile phone, a tablet computer, a computer with a wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a vehicle-mounted terminal, an RSU with terminal function, etc. The terminal device of the present application may also be a vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip or vehicle-mounted unit that is built into the vehicle as one or more components or units. The vehicle can implement the random access method provided by the present application through the built-in vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip or vehicle-mounted unit.

[0134] It should be noted that the random access method provided in the embodiment of the present application can be applied to Figure 4 For the specific implementation between the terminal device and the network equipment shown, reference can be made to the following method embodiments, which will not be repeated here.

[0135] It should be pointed out that the solutions in the embodiments of the present application can also be applied to other communication systems, and the corresponding names can also be replaced by the names of corresponding functions in other communication systems.

[0136] It should be understood that Figure 4 This is a simplified schematic diagram for ease of understanding only. The communication system may also include other network devices and / or other terminal devices. Figure 4 Not drawn in.

[0137] Based on the above Figure 4In the communication system shown, an embodiment of the present application provides a random access method, in which a network device can indicate to a terminal device a TA corresponding to a first service area where the terminal device is located through first indication information, and after the terminal device obtains the TA, it can send a message 1 to the network device based on the TA. Thus, in the case of random access by a terminal device without GNSS capability, the time difference between the messages 1 of different terminal devices in the first service area arriving at the network device side can be reduced, thereby improving the success rate of random access.

[0138] The following will be combined Figure 5-Figure 8 The random access method provided in the embodiment of the present application is specifically described.

[0139] For example, Figure 5 A flow chart of a random access method provided in an embodiment of the present application. The random access method can be applied to Figure 4 Communication between terminal devices and network equipment is shown.

[0140] like Figure 5 As shown, the random access method includes the following steps:

[0141] S501: The network device sends first indication information to the terminal apparatus. Correspondingly, the terminal apparatus receives the first indication information from the network device.

[0142] The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance. The first service area is a service area where the terminal device is located.

[0143] In a possible design, at least one first timing advance is related to at least one distance. The at least one distance is a distance between at least one first location in the first service area and the network device.

[0144] Optionally, the first indication information may include at least one distance. In this case, the first indication information may indicate at least one first timing advance by indicating at least one distance.

[0145] Or, optionally, the first indication information may include at least one first position. In this case, the first indication information may indicate the first timing advance by indicating at least one first position.

[0146] In this case, the terminal device may determine the first time advance according to each first position of the at least one first position and the position of the network device. The position of the network device may be determined by the terminal device according to the operation information of the network device. For example, when the network device is a satellite, the operation information may be ephemeris information. For the ephemeris information, reference may be made to the relevant introduction in S301, which will not be repeated here.

[0147] Alternatively, the first indication information may include at least one parameter corresponding to at least one first timing advance, that is, the first indication information may indicate the first timing advance through at least one parameter corresponding to at least one first timing advance. It is understandable that the at least one parameter may be related to at least one distance.

[0148] Optionally, one of the at least one first positions may be: a position farthest from the network device in the first service area, or a position closest to the network device in the first service area, or a central position of the first service area. The at least one first time advance may include one first time advance, or multiple first time advances. The at least one distance may include one distance or multiple distances. Each time advance in the at least one first time advance may be determined based on one distance or two distances of the at least one distance. The distances used to determine different first time advances are different.

[0149] For example, each first timing advance of the at least one first timing advance may be a round-trip delay between a first position corresponding to the first timing advance and a reference point.

[0150] For ease of understanding, the following combination Figure 4 Assume that the first service area is Figure 4 As shown. Among them, the position farthest from the network device in the first service area is position P1, the position closest to the network device in the first service area is P2, and the center position of the first service area is P3. Then, one of the at least one first position can be a position from position P1 to position P3. For example, if one of the at least one first position is position P1, then the first time advance can include the round-trip delay between position P1 and the reference point.

[0151] For another example, the at least one first position may include position P1 and position P2, then the at least one first time advance may include the round-trip delay between position P1 and the reference point, and the round-trip delay between position P2 and the reference point.

[0152] Here, one of the at least one first position is only used as an example. In actual implementation, the first position of the at least one position can be any other possible position in the first service area, which will not be described in detail here.

[0153] It should be understood that the number of at least one first position and the number of at least one distance may be the same. In addition, when the number of at least one first position is multiple, each position in the at least one first position is different.

[0154] It can be understood that the first indication information may indicate at least one first time advance corresponding to each service area in multiple service areas of the network device. The first service area may be one of the multiple service areas. Assuming that each service area corresponds to a first time advance, the service area and the first time advance are as shown in Table 2. Assuming that the multiple service areas of the network device include service area 1 to service area n, the first time advances corresponding to service area 1 to service area n are time advance 1 to first time advance n respectively.

[0155] Table 2

[0156] Service Area Time Advance Service Area 1 First time advance 1 …… …… Service area First time advance n

[0157] It should be understood that each of the multiple service areas of the network device corresponds to a beam or a cell. In other words, each of the multiple service areas of the network device is a beam or a coverage area of ​​a cell. It can also be said that in the first indication information, each of the multiple service areas of the network device can be represented by a beam identifier or a synchronization signal and physical broadcast channel block (SSB) identifier. Therefore, the terminal device can determine the first service area based on the first corresponding relationship indicated by the first indication information and the beam or cell carrying the first indication information. Among them, the terminal device can determine the beam or cell carrying the first indication information through a broadcast message, such as a system information block (SIB). In other words, the identifier of the beam carrying the first indication information or the identifier of the cell can be carried in the broadcast message.

[0158] It is understandable that the center position of the first service area can also be the center position of the beam or cell corresponding to the first service area. In some possible designs, the center position of the first service area can be the position of the geometric center of the first service area.

[0159] In this way, at least one first timing advance can be matched with at least one first position in the network device and the first service area, further improving the success rate of random access.

[0160] Optionally, the first indication information may also be used to indicate a second correspondence between different GNSS capabilities and the CP length of the random access preamble code.

[0161] In the embodiment of the present application, different GNSS capabilities refer to the GNSS capability states of different terminal devices, which may include GNSS capability and no GNSS capability. Among them, GNSS capability means that the terminal device has GNSS capability, and no GNSS capability means that the terminal device does not have GNSS capability. Among them, the second corresponding relationship is shown in Table 3 below. The CP length of the random access preamble corresponding to the GNSS capability is the first CP length, and the CP length of the random access preamble corresponding to the no GNSS capability is the second CP length. In the second corresponding relationship, the CP length of the random access preamble corresponding to the no GNSS capability is greater than the CP length of the random access preamble corresponding to the GNSS capability, that is, the first CP length is less than or equal to the second CP length. The CP length corresponding to the GNSS capability is the CP length of the random access preamble used for random access by the terminal device with GNSS capability. The CP length corresponding to the no GNSS capability is the CP length of the random access preamble used for random access by the terminal device without GNSS capability.

[0162] Table 3

[0163] GNSS capability status of the terminal device CP length GNSS capable First CP length No GNSS capability Second CP length

[0164] In this way, the CP length of the random access preamble code used by a terminal device without GNSS capability can be made longer than the CP length of the random access preamble code used by a terminal device with GNSS capability. Therefore, when the first service area is large, the random access preamble codes of the terminal devices in the first service area can still be aligned on the network equipment side, thereby improving the success rate of random access.

[0165] It is understood that in the embodiments of the present application, a terminal device with GNSS capability refers to a device or module including the terminal device, such as the terminal device has GNSS capability. A terminal device without GNSS capability refers to a device or module including the terminal device, such as the terminal device without GNSS capability. The GNSS capability of the terminal device refers to a device or module including the terminal device, such as the GNSS capability of the terminal device.

[0166] Optionally, the first indication information may also be used to indicate the correspondence between the GNSS capability of the terminal device and the set of time-frequency resources used for random access.

[0167] Optionally, the first indication information may also be used to indicate a correspondence between the GNSS capability of the terminal device and a set of time-frequency resources used for random access, that is, a third correspondence.

[0168] Among them, the correspondence between GNSS capability and the set of time-frequency resources used for random access includes: the correspondence between terminal devices with GNSS capability and the set of time-frequency resources used for random access, and the correspondence between terminal devices without GNSS capability and the set of time-frequency resources used for random access. For example, in the third correspondence, GNSS capability corresponds to the first set of time-frequency resources, and no GNSS capability corresponds to the second set of time-frequency resources. For the third correspondence, please refer to the following Table 4. The set of time-frequency resources corresponding to GNSS capability is the set of time-frequency resources used for random access by terminal devices with GNSS capability. The set of time-frequency resources corresponding to no GNSS capability is the set of time-frequency resources for the random access preamble code used by terminal devices without GNSS capability for random access.

[0169] Table 4

[0170] GNSS capability status of the terminal device Time-frequency resource collection GNSS capable The first time-frequency resource collection No GNSS capability Second time-frequency resource collection

[0171] Optionally, the time domain position of the time-frequency resource set for random access corresponding to the terminal device with GNSS capability is located before the time domain position of the time-frequency resource set for random access corresponding to the terminal device without GNSS capability. In this way, the service efficiency of the entire communication system can be improved.

[0172] In one possible design, the terminal device is a terminal device without GNSS capability, and the network device is a satellite or a drone.

[0173] It should be understood that the first indication information can be carried in RRC signaling.

[0174] S502: The terminal device sends a message 1 to the network device according to at least one first timing advance. Correspondingly, the network device receives the message 1 from the terminal device.

[0175] Among them, message 1 is used for random access. It should be understood that message 1 includes a random access preamble code.

[0176] The random access preamble may be configured by the network device for the terminal device. For example, the network device may carry the identifier of the random access preamble in a broadcast message, such as a master information block (MIB) or SIB, and a dedicated signaling, such as RRC signaling.

[0177] The random access preamble is explained below in combination with different situations.

[0178] In a possible design scheme, when the first indication information is also used to indicate the second corresponding relationship, the CP length of the random access preamble code in message one is determined according to the GNSS capability of the terminal device and the second corresponding relationship.

[0179] For example, taking the first CP length and the second CP length as an example, if the terminal device corresponding to the terminal device has GNSS capability, then the CP length of the random access preamble in message 1 is the first CP length. If the terminal device corresponding to the terminal device does not have GNSS capability, then the CP length of the random access preamble in message 1 is the second CP length.

[0180] In this way, the CP length of the random access preamble code used for the terminal device can be matched with the GNSS capability of the terminal device, so that when the terminal device has no GNSS capability, the success rate of the terminal device's random access to the network device can be further improved based on at least one first time advance indicated by the network device.

[0181] The CP length of the random access preamble is related to the cell or beam radius corresponding to the first service area. For example, if the beam radius corresponding to the first service area is 500 km, the elevation angle of the farthest point between the first service area and the network device is 10°, and the transmission delay corresponding to each 1 km is 6.7 microseconds (us), then the CP length of the random access preamble is T CP The following relationship must be satisfied: CP =(D02-D01)*6.7us. Wherein, D01 is the fourth distance, i.e., the shortest distance between the terminal device and the network device in the service area, and D02 is the third distance, i.e., the farthest distance N between the terminal device and the network device in the service area. CP RA =T CP / T C =202030k, where T C Corresponding to the sampling interval when the subcarrier interval is 480 kilohertz (kHz), k=64 is an auxiliary parameter.

[0182] In a possible design, the random access preamble carried in the message 1 can be determined according to the existing technology. At this time, the implementation principle of the message 1 can refer to the relevant introduction in S303, which will not be repeated here.

[0183] The terminal device sends message one to the network device according to at least one first time advance, that is, the terminal device determines the target time advance according to at least one first time advance, and sends message one to the network device according to the target time advance.

[0184] Wherein, if the at least one first time advance includes a first time advance, then the target time advance is the first time advance. If the at least one first time advance includes multiple first time advances, then the target time advance may be one of the multiple first time advances, or the range of the target time advance is between the minimum value and the maximum value of the multiple first time advances.

[0185] In a possible design, the network device receiving a message 1 from the terminal apparatus may include: the network device receiving the message 1 from the terminal apparatus within a first time period, wherein the length of the first time period is related to a random access preamble code carried by the message 1.

[0186] In this way, the time length for the network device to receive message one can match the cyclic shift value of the random access preamble code, so that the time length for receiving the message matches the range of the first service area, thereby improving the detection success rate of message one and further improving the random access success rate.

[0187] Optionally, the length of the first time period is related to a cyclic shift value of a preamble sequence of a random access preamble code carried by message 1, and the cyclic shift (CS) value of the preamble sequence of the random access preamble code carried by message 1 is determined according to the radius of the first service area.

[0188] For example, the cyclic shift value CS of the preamble sequence of the random access preamble code carried by message 1 can be calculated by the following formula:

[0189] CS = (π / 6)*R;

[0190] Wherein, π / 6 represents an angle unit, and R represents the length of the radius of the first service area. It can be understood that the radius of the first service area may be the length of the radius of a cell covering the first service area.

[0191] In this way, when the range of the first service area is larger, the message one can be received in a longer time, thereby improving the detection success rate of the message one and further improving the random access success rate.

[0192] In a possible design scheme, the implementation principle of the network device receiving the message 1 from the terminal device can refer to the relevant introduction of S303, which will not be repeated here.

[0193] S503, the network device sends message 2 to the terminal device. Correspondingly, the terminal device receives message 2 from the network device.

[0194] Among them, message two is used to indicate the time-frequency resources carrying message three.

[0195] For the implementation principle of message two, please refer to the relevant introduction in S304, which will not be repeated here. The difference is that, when the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access, the time-frequency resources carrying message three are the time-frequency resources in the time-frequency resource set for random access corresponding to the terminal device. The time-frequency resource set for random access corresponding to the terminal device is the time-frequency resource set for random access corresponding to the GNSS capability of the terminal device corresponding to the terminal device.

[0196] Optionally, when the first indication information is also used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access, message 2 includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying message 3. In other words, the time-frequency resources carrying message 3 can be carried in the second indication information in message 2.

[0197] Optionally, the second indication information may indicate that the time domain position of the time-frequency resource set for random access corresponding to the terminal device with GNSS capability is located before the time domain position of the time-frequency resource set for random access corresponding to the terminal device without GNSS capability. In this way, the service efficiency of the entire communication system can be improved.

[0198] The second indication information may indicate the first time advance. For example, the second indication information may carry an index of the first time advance, namely, TAC. For example, the beam radius corresponding to the first service area is 500 km, the elevation angle of the farthest point between the first service area and the network device is 10°, and the transmission delay corresponding to each 1 km is 6.7 microseconds (microsecond, us), and the bit position occupied by TAC is 14 bits.

[0199] In this way, the first indication information can indicate the correspondence between different GNSS capabilities and the time-frequency resource sets used for random access, and the time-frequency resources used to carry message three can be determined from the time-frequency resource sets used for random access corresponding to the terminal devices without GNSS capabilities.

[0200] In a possible design, S503 may include: the terminal device receives a second message from the network device after the first moment. The time length between the end moment when the terminal device sends the first message and the first moment is the first time length.

[0201] The first moment is a moment after the terminal device sends message 1.

[0202] Optionally, the first time length is twice the first time advance.

[0203] In this way, after sending message one, the terminal device can wait for a first time length, such as twice the first time advance, and then open the monitoring window to monitor message two. In this way, the time for monitoring message two can be reduced, thereby reducing the power consumption of the terminal device.

[0204] It is understandable that the first time length being twice the first time advance is only used as an example. In actual implementation, the first time length may also be other time lengths, which will not be described in detail here.

[0205] In another possible design scheme, the implementation principle of S503 can also refer to the relevant introduction in S304, which will not be repeated here.

[0206] S504, the terminal device sends message 3 to the network device according to the time-frequency resources indicated by message 2. Correspondingly, the network device receives message 3 from the terminal device on the time-frequency resources. Message 3 includes identification information of the terminal device.

[0207] For the implementation principle of message three, please refer to the relevant introduction of S305. For the implementation principle of S504, please refer to the relevant introduction in S305, which will not be repeated here.

[0208] S505, the network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the network device.

[0209] Among them, message four is used to indicate that the terminal device contention resolution is successful.

[0210] For the implementation principle of message 4, please refer to the relevant introduction in S306, which will not be repeated here.

[0211] In a possible design, S505 may include: the terminal device receives a message 4 from the network device after the second moment. The time length between the end moment when the terminal device sends the message 3 and the second moment is the second time length.

[0212] The second moment is a moment after the end moment of sending the third message by the terminal device.

[0213] Optionally, the second time length is twice the first time advance.

[0214] In this way, after sending message three, the terminal device can wait for a second time length, such as twice the first time advance, and then open the monitoring window to monitor message four. In this way, the time for monitoring message four can be reduced, thereby reducing the power consumption of the terminal device.

[0215] It can be understood that the second time length being twice the first time advance is only used as an example. In actual implementation, the second time length may also be other time lengths, which will not be described in detail here.

[0216] In the embodiment of the present application, the first time length and the second time length can be configured through a broadcast message, such as SIB.

[0217] In another possible design scheme, the implementation principle of S505 can also refer to the relevant introduction in S306, which will not be repeated here.

[0218] based on Figure 5 According to the provided random access method, a network device can configure at least one first time advance corresponding to a first service area where the terminal device is located for a terminal device, so that the terminal device can send message one based on the at least one first time advance to achieve time pre-compensation of message one, so that message one can be aligned with message one of other terminal devices on the network device side, thereby improving the success rate of random access.

[0219] For ease of understanding, the following describes the above scenarios in different scenarios. Figure 5 The random access method is provided for description.

[0220] In some scenarios, the service area where the terminal device is located, that is, the first service area, is relatively small. For example, when the radius of the first service area is less than 100km, the TA indicated by the network device can achieve the purpose of aligning the message of the terminal device in the first service area. Understandable. The radius of the first service area is less than 100km only for example. In actual implementation, the radius of the first service area can also be other ranges, which will not be repeated here. At this time, the terminal device can send message 1 for random access according to the TA indicated by the first indication information. For the random access method in this scenario, please refer to Figure 6 .

[0221] like Figure 6 As shown, the random access method includes:

[0222] S601: The network device sends first indication information to the terminal apparatus. Correspondingly, the terminal apparatus receives the first indication information from the network device.

[0223] The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance. The first service area is a service area where the terminal device is located.

[0224] For the implementation principle of the first service area, at least one first timing advance and the first corresponding relationship, reference may be made to the relevant introduction in S501, which will not be repeated here.

[0225] In a possible design, the terminal device is a terminal device without GNSS capability, and the network device is a satellite. It is understandable that the network device can also be a drone or the like.

[0226] Optionally, the first indication information may also be used to indicate a correspondence between different GNSS capabilities and a set of time-frequency resources used for random access.

[0227] For the implementation principle that the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access, reference can be made to the relevant introduction in S501, which will not be repeated here.

[0228] For the implementation principle of S601, please refer to the relevant introduction of S501, which will not be repeated here.

[0229] S602: The terminal device sends a message 1 to the network device according to at least one first timing advance. Correspondingly, the network device receives the message 1 from the terminal device.

[0230] Among them, message 1 is used for random access. Message 1 carries a random access preamble.

[0231] The random access preamble carried in the message 1 can be determined according to the existing technology. At this time, the implementation principle of the message 1 can refer to the relevant introduction in S303; the implementation principle of the terminal device sending the message 1 to the network device according to at least one first time advance in S602 can refer to the relevant introduction in S502, and the implementation principle of the network device receiving the message 1 from the terminal device can refer to the relevant introduction in S302, which will not be repeated here.

[0232] S603, the network device sends message 2 to the terminal device. Correspondingly, the terminal device receives message 2 from the network device.

[0233] Among them, message two is used to indicate the time-frequency resources carrying message three.

[0234] For the implementation principle of message 2, please refer to the relevant introduction in S503, and for the implementation principle of S603, please refer to the relevant introduction in S503, which will not be repeated here.

[0235] S604, the terminal device sends message 3 to the network device according to the time-frequency resources indicated by message 2. Correspondingly, the network device receives message 3 from the terminal device on the time-frequency resources.

[0236] Among them, message three includes identification information of the terminal device.

[0237] For the implementation principle of message three, please refer to the relevant introduction in S504, and for the implementation principle of S604, please refer to the relevant introduction in S504, which will not be repeated here.

[0238] S605, the network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the network device.

[0239] For the implementation principle of message 4, please refer to the relevant introduction in S505. For the implementation principle of S605, please refer to the relevant introduction in S505, which will not be repeated here.

[0240] about Figure 6 The technical effect of the provided method can be referred to Figure 5 The relevant introduction in will not be repeated here.

[0241] In other scenarios, the service area where the terminal device is located, that is, the first service area, is larger. For example, when the radius of the first service area is greater than or equal to 100km, the TA indicated by the network device and the CP length of the random access preamble code can be combined to achieve the purpose of aligning the message of the terminal device in the first service area. It is understandable. The radius of the first service area is greater than or equal to 100km is only used as an example. In actual implementation, the radius of the first service area can also be other ranges, which will not be repeated here. At this time, the terminal device can send message one for random access according to the TA indicated by the first indication information and the CP length of the random access preamble code corresponding to the GNSS capability. For the random access method in this scenario, please refer to Figure 7 .

[0242] like Figure 7 As shown, the random access method includes:

[0243] S701, the network device sends first indication information to the terminal device. Correspondingly, the terminal device receives the first indication information from the network device.

[0244] The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance. The first service area is a service area where the terminal device is located.

[0245] In addition, the first indication information is also used to indicate the second corresponding relationship. For the implementation principle of the second corresponding relationship, reference may be made to the relevant introduction in S501.

[0246] For the implementation principle of the first indication information, reference may be made to the relevant introduction in S501, and for the implementation principle of S701, reference may be made to the relevant introduction in S501, which will not be repeated here.

[0247] S702: The terminal device sends a message 1 to the network device according to at least one first timing advance. Correspondingly, the network device receives the message 1 from the terminal device.

[0248] Among them, message 1 is used for random access and carries a random access preamble.

[0249] The CP length of the random access preamble in the message 1 is determined according to the GNSS capability of the terminal device and the second corresponding relationship.

[0250] The CP length of the random access preamble in message one is determined according to the GNSS capability of the terminal device and the second corresponding relationship. Please refer to the relevant introduction in S502. The implementation principle of S702 may refer to the relevant introduction in S502, which will not be repeated here.

[0251] S703, the network device sends message 2 to the terminal device. Correspondingly, the terminal device receives message 2 from the network device.

[0252] Among them, message two is used to indicate the time-frequency resources carrying message three.

[0253] For the implementation principle of message 2, please refer to the relevant introduction in S503, and for the implementation principle of S603, please refer to the relevant introduction in S503, which will not be repeated here.

[0254] S704, the terminal device sends message 3 to the network device according to the time-frequency resources indicated by message 2. Correspondingly, the network device receives message 3 from the terminal device on the time-frequency resources.

[0255] Among them, message three includes identification information of the terminal device.

[0256] For the implementation principle of message three, please refer to the relevant introduction in S504, and for the implementation principle of S704, please refer to the relevant introduction in S504, which will not be repeated here.

[0257] S705, the network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the network device.

[0258] For the implementation principle of message 4, please refer to the relevant introduction in S505. For the implementation principle of S705, please refer to the relevant introduction in S505, which will not be repeated here.

[0259] about Figure 7 The technical effect of the provided method can be referred to Figure 5 The relevant introduction in will not be repeated here.

[0260] In some scenarios, the service area where the terminal device is located, that is, the first service area, is relatively small. For example, when the radius of the first service area is greater than or equal to 100 km, the reception of message 1 by the terminal device in the first service area can be achieved by combining the TA indicated by the network device and the length of the network device receiving time. Understandable. The radius of the first service area is greater than or equal to 100 km only for example. In actual implementation, the radius of the first service area can also be other ranges, which will not be repeated here.

[0261] At this time, the terminal device can send message 1 according to the TA indicated by the first indication information to perform random access. For the random access method in this scenario, please refer to Figure 8 .

[0262] like Figure 8 As shown, the random access method includes:

[0263] S801, the network device sends first indication information to the terminal device. Correspondingly, the terminal device receives the first indication information from the network device.

[0264] The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance. The first service area is a service area where the terminal device is located.

[0265] For the implementation principle of the first service area, at least one first timing advance and the first corresponding relationship, reference may be made to the relevant introduction in S501, which will not be repeated here.

[0266] In a possible design, the terminal device is a terminal device without GNSS capability, and the network device is a satellite. It is understandable that the network device can also be a drone or the like.

[0267] Optionally, the first indication information may also be used to indicate a correspondence between different GNSS capabilities and a set of time-frequency resources used for random access.

[0268] For the implementation principle that the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access, reference can be made to the relevant introduction in S501, which will not be repeated here.

[0269] For the implementation principle of S801, please refer to the relevant introduction of S501, which will not be repeated here.

[0270] S802: The terminal device sends a message 1 to the network device according to at least one first timing advance. Correspondingly, the network device receives the message 1 from the terminal device.

[0271] Among them, message 1 is used for random access. Message 1 carries a random access preamble.

[0272] The random access preamble carried in the message 1 can be determined according to the existing technology. At this time, the implementation principle of the message 1 can refer to the relevant introduction in S303; the implementation principle of the terminal device sending the message 1 to the network device according to at least one first time advance in S802 can refer to the relevant introduction in S502.

[0273] Regarding the network device receiving the message 1 from the terminal device, it may include: the network device receives the message 1 from the terminal device within a first time period, wherein the length of the first time period is related to the random access preamble code carried by the message 1.

[0274] For the implementation principle of the first time length, please refer to the relevant introduction in S802, which will not be repeated here.

[0275] S803, the network device sends message 2 to the terminal device. Correspondingly, the terminal device receives message 2 from the network device.

[0276] Among them, message two is used to indicate the time-frequency resources carrying message three.

[0277] For the implementation principle of message 2, please refer to the relevant introduction in S503. For the implementation principle of S803, please refer to the relevant introduction in S503, which will not be repeated here.

[0278] S804, the terminal device sends message 3 to the network device according to the time-frequency resources indicated by message 2. Correspondingly, the network device receives message 3 from the terminal device on the time-frequency resources.

[0279] Among them, message three includes identification information of the terminal device.

[0280] For the implementation principle of message three, please refer to the relevant introduction in S504, and for the implementation principle of S804, please refer to the relevant introduction in S504, which will not be repeated here.

[0281] S805, the network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the network device.

[0282] For the implementation principle of message 4, please refer to the relevant introduction in S505. For the implementation principle of S805, please refer to the relevant introduction in S505, which will not be repeated here.

[0283] about Figure 8 The technical effect of the provided method can be referred to Figure 5 The relevant introduction in will not be repeated here.

[0284] Combination of the above Figure 5-Figure 8The random access method provided in the embodiment of the present application is described in detail. Fig. 9 and Fig.10 A communication device for executing the random access method provided in an embodiment of the present application is described in detail.

[0285] For example, Fig. 9 Schematic diagram of a communication device provided in an embodiment of the present application. Fig. 9 As shown, the communication device 900 includes: a processing module 901 and a transceiver module 902. For ease of description, Fig. 9 Only the main components of the communication device 900 are shown.

[0286] In some embodiments, the communication device 900 may be suitable for Figure 4 In the communication system shown in FIG. , execution Figure 5-Figure 8 The function of the communication device 900 in the random access method shown in any one of the items.

[0287] The transceiver module 902 is used to receive first indication information from a network device.

[0288] The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance. The first service area is a service area where the communication device 900 is located.

[0289] The processing module 901 is used to generate message 1. Message 1 is used for random access.

[0290] The transceiver module 902 is further configured to send message 1 to the network device according to at least one first timing advance.

[0291] In a possible design, at least one first timing advance is related to at least one distance. The at least one distance is a distance between at least one first location in the first service area and the network device.

[0292] Optionally, one of the at least one first position may be: a position farthest from the network device in the first service area, or a position closest to the network device in the first service area, or a central position of the first service area.

[0293] In one possible design, the first indication information may also be used to indicate a second correspondence between different GNSS capabilities and the CP length of the random access preamble. Message one includes the random access preamble, and the CP length of the random access preamble in message one is determined according to the GNSS capability of the terminal device and the second correspondence.

[0294] Optionally, in the second corresponding relationship, the CP length of the random access preamble code corresponding to the non-GNSS capability is greater than the CP length of the random access preamble code corresponding to the GNSS capability.

[0295] In a possible design scheme, the transceiver module 902 is further used to receive a message 2 from the network device. The message 2 is used to indicate the time-frequency resources carrying the message 3. The transceiver module 902 is further used to send a message 3 to the network device according to the time-frequency resources indicated by the message 2. The message 3 includes the identification information of the communication device 900. The transceiver module 902 is further used to receive a message 4 from the network device. The message 4 is used to indicate that the communication device 900 successfully resolves the competition.

[0296] Optionally, the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access. Message 2 includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying message 3. The time-frequency resources carrying message 3 are the time-frequency resources in the time-frequency resource set for random access corresponding to the GNSS capability of the terminal device.

[0297] Optionally, the transceiver module 902 is further configured to receive a second message from the network device after the first moment. The time length between the end moment of the communication device 900 sending the first message and the first moment is a first time length. The first time length is twice the first time advance.

[0298] Optionally, the transceiver module 902 is further configured to receive a message 4 from the network device after the second moment. The time length between the end moment of the communication device 900 sending the message 3 and the second moment is the second time length. The second time length is twice the first time advance.

[0299] In one possible design, the communication device 900 is a terminal device without GNSS capability, and the network device is a satellite.

[0300] Optionally, the transceiver module 902 may include a receiving module and a sending module ( Fig. 9 The transceiver module 902 is used to implement the sending function and the receiving function of the communication device 900.

[0301] Optionally, the communication device 900 may further include a storage module ( Fig. 9 (not shown in the figure), the storage module stores a program or instruction. When the processing module 901 executes the program or instruction, the communication device 900 can execute Figure 5-Figure 8 The function of the terminal device in the random access method shown in any one of the items.

[0302] It should be understood that the processing module 901 involved in the communication device 900 can be implemented by a processor or a processor-related circuit component, which can be a processor or a processing unit; the transceiver module 902 can be implemented by a transceiver or a transceiver-related circuit component, which can be a transceiver or a transceiver unit.

[0303] It should be noted that the communication device 900 may be a terminal device, or a chip (system) or other parts or components that can be set in the terminal device, or a device including a terminal device, which is not limited in this application.

[0304] In addition, the technical effects of the communication device 900 can be referred to Figure 5-Figure 8 The technical effects of the random access method shown in any one of the items will not be repeated here.

[0305] In some other embodiments, the communication device 900 may be suitable for Figure 4 In the communication system shown in FIG. , execution Figure 5-Figure 8 The functions of the network device in the random access method shown in .

[0306] The processing module 901 is configured to generate first indication information. The first indication information is used to indicate a first corresponding relationship between a first service area of ​​the communication device 900 and at least one first timing advance. The first service area is a service area where the terminal device is located.

[0307] The transceiver module 902 is configured to send first indication information to the terminal device.

[0308] The transceiver module 902 is further configured to receive a message 1 from the terminal device.

[0309] Among them, message one is sent by the terminal device according to at least one first time advance, and message one is used for random access.

[0310] In a possible design, at least one first timing advance is related to at least one distance. The at least one distance is a distance between at least one first location in the first service area and the communication device 900 .

[0311] Optionally, one of the at least one first position may be: a position farthest from the communication device 900 in the first service area, or a position closest to the communication device 900 in the first service area, or a central position of the first service area.

[0312] In a possible design, the first indication information may also be used to indicate a second correspondence between different GNSS capabilities and the CP length of the random access preamble. The CP length of the random access preamble in the first message is determined according to the GNSS capability of the terminal device and the second correspondence.

[0313] Optionally, in the second corresponding relationship, the CP length of the random access preamble code corresponding to the non-GNSS capability is greater than the CP length of the random access preamble code corresponding to the GNSS capability.

[0314] In a possible design, the transceiver module 902 is further configured to receive a message 1 from the terminal device within a first time period, wherein the length of the first time period is related to the random access preamble code carried by the message 1.

[0315] Optionally, the length of the first time period is positively correlated with a cyclic shift value of a preamble sequence of a random access preamble code carried by message 1.

[0316] In a possible design scheme, the transceiver module 902 is further used to send a second message to the terminal device. The second message is used to indicate the time-frequency resource carrying the third message. The transceiver module 902 is further used to receive a third message from the terminal device on the time-frequency resource. The third message includes identification information of the terminal device. The transceiver module 902 is further used to send a fourth message to the terminal device. The fourth message is used to indicate that the terminal device successfully resolves the contention.

[0317] Optionally, the first indication information can also be used to indicate the correspondence between different GNSS capabilities and the time-frequency resource set for random access. Message 2 includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying message 3. The time-frequency resources carrying message 3 are the time-frequency resources in the time-frequency resource set for random access corresponding to the GNSS capability of the terminal device.

[0318] In one possible design, the terminal device is a terminal device without GNSS capability, and the communication device 900 is a satellite.

[0319] Optionally, the transceiver module 902 may include a receiving module and a sending module ( Fig. 9 The transceiver module 902 is used to implement the sending function and the receiving function of the communication device 900.

[0320] Optionally, the communication device 900 may further include a storage module ( Fig. 9 (not shown in the figure), the storage module stores a program or instruction. When the processing module 901 executes the program or instruction, the communication device 900 can execute Figure 5-Figure 8 The function of the network device in the random access method shown in any one of the items.

[0321] It should be understood that the processing module 901 involved in the communication device 900 can be implemented by a processor or a processor-related circuit component, which can be a processor or a processing unit; the transceiver module 902 can be implemented by a transceiver or a transceiver-related circuit component, which can be a transceiver or a transceiver unit.

[0322] It should be noted that the communication device 900 can be a network device, or a chip (system) or other parts or components that can be set in the network device, or a device that includes a network device, which is not limited in this application.

[0323] In addition, the technical effects of the communication device 900 can be referred to Figure 5-Figure 8 The technical effects of the random access method shown in any one of the items will not be repeated here.

[0324] For example, Fig.10 This is a schematic diagram of the structure of another communication device provided in an embodiment of the present application. The communication device may be a terminal device or a network device, or may be a chip (system) or other components or assemblies that can be set in a terminal device or a network device. Fig.10 As shown, the communication device 1000 may include a processor 1001. Optionally, the communication device 1000 may further include a memory 1002 and / or a transceiver 1003. The processor 1001 is coupled with the memory 1002 and the transceiver 1003, such as being connected via a communication bus.

[0325] Combine the following Fig.10 The components of the communication device 1000 are described in detail:

[0326] The processor 1001 is the control center of the communication device 1000, and may be a processor or a general term for multiple processing elements. For example, the processor 1001 is one or more central processing units (CPUs), or may be an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application, such as one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs).

[0327] Optionally, the processor 1001 may perform various functions of the communication device 1000 by running or executing a software program stored in the memory 1002 , and calling data stored in the memory 1002 .

[0328] In a specific implementation, as an embodiment, the processor 1001 may include one or more CPUs, such as Fig.10 CPU0 and CPU1 are shown in FIG.

[0329] In a specific implementation, as an embodiment, the communication device 1000 may also include multiple processors, such as Fig.10 1001 and 1004 are shown in FIG. Each of these processors may be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). A processor herein may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0330] The memory 1002 is used to store the software program for executing the solution of the present application, and the execution is controlled by the processor 1001. The specific implementation method can refer to the above method embodiment, which will not be repeated here.

[0331] Optionally, the memory 1002 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 1002 may be integrated with the processor 1001, or may exist independently and be accessed through the interface circuit ( Fig.10 (not shown) is coupled to the processor 1001, which is not specifically limited in the embodiment of the present application.

[0332] The transceiver 1003 is used for communication with other communication devices. For example, the communication device 1000 is a terminal device, and the transceiver 1003 can be used to communicate with a network device, or with another terminal device. For another example, the communication device 1000 is a network device, and the transceiver 1003 can be used to communicate with a terminal device, or with another network device.

[0333] Optionally, the transceiver 1003 may include a receiver and a transmitter ( Fig.10 The receiver is used to implement a receiving function, and the transmitter is used to implement a sending function.

[0334] Optionally, the transceiver 1003 may be integrated with the processor 1001, or may exist independently and communicate with the processor 1001 through the interface circuit ( Fig.10 (not shown) is coupled to the processor 1001, which is not specifically limited in the embodiment of the present application.

[0335] It should be noted that Fig.10 The structure of the communication device 1000 shown in the figure does not constitute a limitation on the communication device. The actual communication device may include more or fewer components than those shown in the figure, or combine certain components, or arrange the components differently.

[0336] In addition, the technical effects of the communication device 1000 can refer to the technical effects of the random access method described in the above method embodiment, which will not be repeated here.

[0337] It should be understood that the processor in the embodiment of the present application may be a CPU, and the processor may also be other general-purpose processors, DSPs, ASICs, FPGAs or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0338] It should also be understood that the memory in the embodiment of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memory. Among them, the non-volatile memory can be a ROM, a programmable read-only memory (programmable ROM, PROM), an erasable programmable read-only memory (erasable PROM, EPROM), an EEPROM or a flash memory. The volatile memory can be a RAM, which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (static RAM, SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (doubledata rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (synchlink DRAM, SLDRAM) and direct memory bus random access memory (direct rambus RAM, DR RAM).

[0339] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware or any other combination. When implemented using software, the above embodiments 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 or computer programs. When the computer instructions or computer programs are loaded or 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 site, computer, server or data center to another website site, computer, server or data center by wired (such as infrared, wireless, microwave, etc.). 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 contains one or more available media sets. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0340] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0341] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0342] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0343] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in 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. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0344] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0345] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0346] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0347] 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.

[0348] If the functions are implemented in the form of software functional units and sold or used as independent products, they 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, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0349] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A random access method, characterized in that: Applied to a terminal device, the method comprises: Receive first indication information; wherein the first indication information is used to indicate a first corresponding relationship between a first service area of ​​a network device and at least one first timing advance; the first service area is a service area where the terminal device is located; Message one is sent according to the at least one first time advance; wherein the message one is used for random access.

2. The method according to claim 1, characterized in that: The at least one first timing advance is related to at least one distance; the at least one distance is a distance between at least one first location in the first service area and the network device.

3. The method according to claim 2, characterized in that One of the at least one first position is: a position in the first service area that is farthest from the network device, or a position in the first service area that is closest to the network device, or a central position in the first service area.

4. The method according to any one of claims 1 to 3, characterized in that The first indication information is further used to indicate a second correspondence between different global satellite navigation system GNSS capabilities and the cyclic prefix CP length of the random access preamble code; The message one includes a random access preamble code, and the CP length of the random access preamble code in the message one is determined according to the GNSS capability of the terminal device and the second corresponding relationship.

5. The method according to claim 4, characterized in that In the second corresponding relationship, the CP length of the random access preamble code corresponding to the non-GNSS capability is greater than the CP length of the random access preamble code corresponding to the GNSS capability.

6. The method according to any one of claims 1 to 5, characterized in that The method further comprises: Receive message 2; wherein message 2 is used to indicate the time-frequency resources carrying message 3; Sending the message three according to the time-frequency resources indicated by the message two; wherein the message three includes identification information of the terminal device; Received message four; wherein, the message four is used to indicate that the terminal device contention resolution is successful.

7. The method according to claim 6, characterized in that The first indication information is also used to indicate the correspondence between different GNSS capabilities and a set of time-frequency resources used for random access; the message two includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying the message three; the time-frequency resources carrying the message three are the time-frequency resources in the set of time-frequency resources used for random access corresponding to the GNSS capability of the terminal device.

8. The method according to claim 6, characterized in that Receive message 2, including: Message 2 is received after a first moment; the time length between the end moment of sending the message 1 and the first moment is a first time length; the first time length is twice the first time advance.

9. The method according to claim 6, characterized in that Receive message 4, including: Message four is received after the second moment; the time length between the end moment of sending the message three and the second moment is the second time length; the second time length is twice the first time advance.

10. The method according to any one of claims 1 to 9, characterized in that The terminal device is a terminal device without GNSS capability, and the network device is a satellite.

11. A random access method, characterized in that: Applied to a network device, the method comprises: Sending first indication information; wherein the first indication information is used to indicate a first corresponding relationship between a first service area of ​​the network device and at least one first timing advance; the first service area is a service area where the terminal device is located; Receive message one; wherein, message one is sent by the terminal device according to the at least one first time advance, and message one is used for random access.

12. The method according to claim 11, characterized in that The at least one first timing advance is related to at least one distance; the at least one distance is a distance between at least one first location in the first service area and the network device.

13. The method according to claim 12, characterized in that One of the at least one first position is: a position in the first service area that is farthest from the network device, or a position in the first service area that is closest to the network device, or a central position in the first service area.

14. The method according to any one of claims 11 to 13, characterized in that The first indication information is further used to indicate a second corresponding relationship between the presence or absence of a global satellite navigation system GNSS capability and the cyclic prefix CP length of the random access preamble code; The CP length of the random access preamble code in the message one is determined according to the GNSS capability of the terminal device and the second corresponding relationship.

15. The method according to claim 14, characterized in that In the second corresponding relationship, the CP length of the random access preamble code corresponding to the non-GNSS capability is greater than the CP length of the random access preamble code corresponding to the GNSS capability.

16. The method according to any one of claims 11 to 13, characterized in that: The receiving message 1 comprises: Receive the message one within a first time period; wherein the time length of the first time period is related to the random access preamble code carried by the message one.

17. The method according to claim 16, characterized in that The length of the first time period is positively correlated with the cyclic shift value of the preamble sequence of the random access preamble code carried by the message one.

18. The method according to any one of claims 11 to 17, characterized in that The method further comprises: Send message 2; wherein message 2 is used to indicate the time-frequency resources carrying message 3; Receiving the message three on the time-frequency resource; wherein the message three includes identification information of the terminal device; Send message four, wherein the message four is used to indicate that the terminal device contention resolution is successful.

19. The method according to claim 18, characterized in that The first indication information is also used to indicate the correspondence between different GNSS capabilities and a set of time-frequency resources used for random access; the message two includes second indication information, and the second indication information is used to indicate the time-frequency resources carrying the message three; the time-frequency resources carrying the message three are the time-frequency resources in the set of time-frequency resources used for random access corresponding to the GNSS capability of the terminal device.

20. The method according to any one of claims 11 to 19, characterized in that The terminal device is a terminal device without GNSS capability, and the network device is a satellite.

21. A communication device, characterized in that: The communication device is used to execute the method according to any one of claims 1-10 or any one of claims 11-20.

22. A communication device, characterized in that: The communication device comprises a module for performing the functions as claimed in any one of claims 1-10, or any one of claims 11-20.

23. A communication device, characterized in that: The communication device comprises: a processor; wherein, The processor is used to execute the method according to any one of claims 1-10 or any one of claims 11-20.

24. A communication device, characterized in that: include: processor; The processor is configured to execute a computer program so that the communication device performs the method according to any one of claims 1 to 10 or any one of claims 11 to 20.

25. A communication device, characterized in that: include: processor and interface circuit; wherein, The interface circuit is used to receive code instructions and transmit them to the processor; The processor is configured to execute the code instructions to perform any one of claims 1-10, or the method of any one of claims 11-20.

26. A communication device, characterized in that: The communication device includes a processor and a transceiver, the transceiver is used for information exchange between the communication device and other communication devices, and the processor executes program instructions to perform any one of claims 1-10, or any one of claims 11-20.

27. A computer-readable storage medium, characterized in that: The computer-readable storage medium comprises a computer program or instructions, and when the computer program or instructions are executed on a computer, the computer is caused to perform the method according to any one of claims 1 to 10 or any one of claims 11 to 20.

28. A computer program product, characterized in that The computer program product comprises: a computer program or instructions, and when the computer program or instructions are run on a computer, the computer is caused to perform the method according to any one of claims 1 to 10 or any one of claims 11 to 20.

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