TA (timing advance) determination method and communication device

Abstract

The invention provides a timing advance (TA) determination method and a communication device, which can reduce the occurrence of error jump when the TA adjustment amount is determined, and improve the accuracy of the TA adjustment amount. The method comprises the following steps: the terminal equipment receives a first timing advance command TAC at a first moment; if the first parameter is updated in a first time period before the first moment, the terminal equipment determines the TA adjustment amount according to the component of the first timing advance and the first TAC; and the terminal device communicates with the service satellite according to the TA adjustment amount. Wherein the first timing advance is determined by the terminal equipment at a second moment, and the first time period is a time period from the second moment to the first moment; the first parameter comprises one or more of the following information: positioning information of the terminal equipment, ephemeris information of a service satellite and a public timing advance TA.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a timing advance TA determination method and a communication device. Background Art

[0002] Since different user equipment (UE) are at different distances from the base station, uplink information sent by different UEs will arrive at the base station at different times, which will cause signal interference. Therefore, the base station hopes that the time when signals from different UEs in the same subframe arrive at the base station is basically aligned, so that the base station can correctly receive the uplink data sent by the UE. In order to enable the base station to correctly receive the UE uplink data, timing advance (TA) is introduced.

[0003] In terrestrial communications, the base station can estimate the TA of the UE through the random access preamble sent by the UE (the TA of UEs at different distances from the base station is also different), and then notify the UE of the timing advance command (TAC). The UE can determine the TA adjustment amount based on the TAC. Different UEs send uplink data according to the corresponding different TA adjustment amounts. From the perspective of the base station, all uplink and downlink system frames are aligned, and the base station can receive uplink data from multiple UEs in the same subframe. The above TAC mechanism can be understood as a closed-loop TA adjustment mechanism.

[0004] In satellite communications, the distance between the satellite and the UE is far, the delay is large, and the TA adjustment amount determined only based on TAC is inaccurate. Therefore, in order to ensure uplink synchronization in satellite communications, an open-loop TA adjustment mechanism is additionally introduced. In the open-loop TA adjustment mechanism, the terminal needs to calculate the round-trip transmission delay from the terminal to the satellite based on the ephemeris information and its own geographic location information, and use it as the open-loop TA adjustment information when sending the uplink signal, and adjust the timing of the TAC closed loop in advance to compensate for the error of the open-loop TA adjustment information, and then determine the TA adjustment amount.

[0005] In satellite communications, on the one hand, after receiving the TAC, the terminal determines the current TA by accumulating the previous TA (the TA may compensate for the errors of the global navigation satellite system (GNSS), ephemeris information and public TA information); on the other hand, when the terminal updates its position or monitors ephemeris information, the errors of the ephemeris information, public TA information and GNSS may be accumulated into the TA again. These two aspects cause the TA error to jump, which in turn leads to inaccurate determined TA adjustment amount. Summary of the invention

[0006] The present application provides a timing advance TA determination method and a communication device to reduce error jumps when determining a TA adjustment amount and improve the accuracy of the TA adjustment amount.

[0007] In the first aspect, the present application provides a timing advance TA determination method, which can be executed by a terminal device, and the terminal device can be understood as a UE, a vehicle-mounted device, a chip of a terminal, etc. The present application does not specifically limit the type of the terminal. The terminal can communicate with a satellite. In the present application, the satellite can be a geostationary satellite, a non-geostationary satellite, an artificial satellite, a low-orbit satellite, a medium-orbit satellite, and a high-orbit satellite. The present application does not specifically limit it here. The method includes: the terminal device receives a first timing advance command TAC at a first moment; if the first parameter is updated within a first time period before the first moment, the terminal device determines the TA adjustment amount according to the component of the first timing advance amount and the first TAC; wherein the first timing advance amount is determined by the terminal device at the second moment, and the first time period is the time period between the second moment and the first moment; the first parameter includes one or more of the following information: the positioning information of the terminal device, the ephemeris information of the service satellite, and the public timing advance TA; and the terminal device communicates with the service satellite according to the TA adjustment amount.

[0008] In the above design, the first parameter update is used as a trigger condition to reduce the error compensation of the closed-loop TA adjustment mechanism part (TA corresponding to TAC), which can reduce the error jump when determining the TA adjustment amount and ensure the accuracy of the TA adjustment amount.

[0009] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0010] T TA =(N TA_new +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0011] in, N TA_old is the first timing advance, α×N TA_old represents the component of the first timing advance, 0≤α<1, T A is the timing advance determined based on the first TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specific The timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,common N is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0012] The above method can be applied to specific communication scenarios. In different communication scenarios, the information included in the first parameter can be different. The specific information of the first parameter in different communication scenarios is described in detail below.

[0013] In one possible design, the service satellite is a geostationary orbit GEO satellite, and the first parameter includes positioning information of the terminal device.

[0014] In one possible design, the service satellite is a low-orbit LEO satellite and the terminal device is in a stationary state, and the first parameter includes ephemeris information of the service satellite.

[0015] In a possible design, the service satellite is a low-orbit LEO satellite, and the terminal device is in a mobile state, then the first parameter includes the positioning information of the terminal device and / or the ephemeris information of the service satellite. Specifically, in this design, the information included in the first parameter is related to one or more of the moving speed of the terminal device, the orbital height of the service satellite, the error of the ephemeris satellite, and the error of the positioning information. Some examples are as follows:

[0016] If the moving speed of the terminal device is greater than a first speed threshold, the first parameter includes the positioning information of the terminal device and the ephemeris information of the service satellite; or, if the moving speed of the terminal device is less than a second speed threshold, the first parameter includes the ephemeris information of the service satellite; or, if the orbital altitude of the service satellite is lower than the first altitude threshold, the first parameter includes the ephemeris information of the service satellite; or, if the orbital altitude of the service satellite is higher than the second altitude threshold, the first parameter includes the positioning information of the terminal device; or, if the moving speed of the terminal device is greater than the first speed threshold and the orbital altitude of the service satellite is higher than the second altitude threshold, the first parameter includes the positioning information of the terminal device; or, if the moving speed of the terminal device is less than the second speed threshold and the orbital altitude of the service satellite is lower than the first altitude threshold, the first parameter includes the ephemeris information of the service satellite; or, if the error corresponding to the ephemeris information of the service satellite is less than the first error threshold, the first parameter includes the positioning information of the terminal device; or, if the error corresponding to the positioning information of the terminal device is less than the second error threshold, the first parameter includes the ephemeris information of the terminal device.

[0017] Optionally, the threshold in the above design may be indicated to the terminal device by the service satellite, or may be predefined or configured in the terminal device. For example, before determining the TA adjustment amount, the terminal device may also perform the following operations: receiving first information from the service satellite, where the first information is used to indicate one or more of the following: a first speed threshold, a second speed threshold, a first altitude threshold, a second altitude threshold, a first error threshold, and a second error threshold.

[0018] In the second aspect, the present application provides a timing advance TA determination method, which can be executed by a terminal device, which can be understood as a UE, a vehicle-mounted device, a chip of a terminal, etc. The present application does not specifically limit the type of terminal. The terminal can communicate with a satellite. In the present application, the satellite can be a geostationary satellite, a non-geostationary satellite, an artificial satellite, a low-orbit satellite, a medium-orbit satellite, and a high-orbit satellite, which is not specifically limited in the present application.

[0019] The method includes: a terminal device receives first information, the first information indicates I moments when the terminal device sends a random access sequence, the interval between every two moments in the I moments is the same, and I is a positive integer greater than 1; the terminal device sends a random access sequence at the i-th moment in the I moments, and receives a second timing advance command TAC at the third moment; wherein the third moment is a moment between the i-th moment and the i+1-th moment, and i is a positive integer from 1 to I-1; the terminal device determines a TA adjustment amount according to the second TAC; wherein the second timing advance amount is determined by the terminal device before the third moment; and the terminal device communicates with a service satellite according to the TA adjustment amount.

[0020] In the above design, the terminal device sends a random access sequence based on the historical TAC accumulation N TA The characteristic of returning to zero is configured to periodically send a random access sequence to achieve periodic and multiple reductions in the error compensation of the closed-loop TA adjustment mechanism, which can reduce the error jump when determining the TA adjustment amount and ensure the accuracy of the TA adjustment amount.

[0021] In one possible design, the second TAC is the first TAC received by the terminal device after the i-th moment. Optionally, the effective time of the TA adjustment amount determined based on the second TAC is the time period between the third moment and the next TAC after receiving the second TAC.

[0022] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0023] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0024] in, T A is the timing advance determined based on the second TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specific The timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,commonN is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0025] In one possible design, before receiving the first information, the terminal device may also send second information to the service satellite, where the second information is used to indicate the valid time of the positioning information of the terminal device, and the second information is used to determine the interval between every two moments in I moments.

[0026] In the third aspect, the present application provides a timing advance TA determination method, which can be executed by a terminal device, which can be understood as a UE, a vehicle-mounted device, a chip of a terminal, etc. The present application does not specifically limit the type of terminal. The terminal can communicate with a satellite. In the present application, the satellite can be a geostationary satellite, a non-geostationary satellite, an artificial satellite, a low-orbit satellite, a medium-orbit satellite, and a high-orbit satellite, which is not specifically limited in the present application.

[0027] The method includes: when the terminal device determines to update the first parameter, the terminal device sends the second information to the service satellite, and the second information is used to request the configuration information of the random access sequence; wherein the first parameter includes one or more of the following information: the positioning information of the terminal device, the ephemeris information of the service satellite, and the public timing advance TA information; the terminal device sends the random access sequence according to the received configuration information of the random access sequence; the terminal device receives a third timing advance command TAC, and determines the TA adjustment amount according to the third TAC; wherein the third TAC is the first TAC received by the terminal device after sending the random access sequence; the terminal device communicates with the service satellite according to the TA adjustment amount.

[0028] In the above design, the terminal device uses the N corresponding to the historical TAC accumulated when sending the random access sequence TA The zeroing feature requests the network side to send a random access sequence during the positioning information or ephemeris information update process to reduce the error compensation of the closed-loop TA adjustment mechanism part, which can reduce the error jump when determining the TA adjustment amount and ensure the accuracy of the TA adjustment amount.

[0029] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0030] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0031] in, T Ais the timing advance determined based on the third TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specific The timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,common N is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0032] In a fourth aspect, the present application provides a communication device, which can be used to execute the method of the first aspect. The device may be a terminal device, or the device may be a component in the terminal device (for example, a chip, or a chip system, or a circuit), or may be a device that can be used in combination with the terminal device.

[0033] In a possible implementation, the communication device may include a module or unit corresponding to the method / operation / step / action described in the first aspect, and the module or unit may be a hardware circuit, or software, or a combination of a hardware circuit and software. In a possible implementation, the device may include a processing unit (also referred to as a processing module) and a communication unit (also referred to as a communication module), wherein the communication unit may be used to perform the functions of receiving and / or sending, and the processing unit may be used to perform the above-mentioned first aspect or any possible implementation method of the first aspect.

[0034] Taking the communication device including a communication module and a processing module as an example, the functions of each module can be understood as follows:

[0035] The communication module is configured to receive a first timing advance command TAC at a first moment.

[0036] A processing module is used to determine a TA adjustment amount according to components of a first timing advance and a first TAC when a first parameter is updated within a first time period before a first moment; wherein the first timing advance is determined by a terminal device at a second moment, and the first time period is a time period from the second moment to the first moment; and the first parameter includes one or more of the following information: positioning information of the terminal device, ephemeris information of a service satellite, and a public timing advance TA.

[0037] The communication module is also used to communicate with the service satellite according to the TA adjustment amount.

[0038] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0039] T TA =(N TA_new +N TA,UE-specific +NTA,common +N TA,offset )×T c ;

[0040] in, N TA_old is the first timing advance, α×N TA_old represents the component of the first timing advance, 0≤α<1, T A is the timing advance determined based on the first TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specific The timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,common N is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0041] The above communication device can be applied to specific communication scenarios, and the information included in the first parameter can be different in different communication scenarios. The specific information of the first parameter in different communication scenarios is described in detail below.

[0042] In one possible design, the service satellite is a geostationary orbit GEO satellite, and the first parameter includes positioning information of the terminal device.

[0043] In one possible design, the service satellite is a low-orbit LEO satellite and the terminal device is in a stationary state, and the first parameter includes ephemeris information of the service satellite.

[0044] In a possible design, the service satellite is a low-orbit LEO satellite, and the terminal device is in a mobile state, then the first parameter includes the positioning information of the terminal device and / or the ephemeris information of the service satellite. Specifically, in this design, the information included in the first parameter is related to one or more of the moving speed of the terminal device, the orbital height of the service satellite, the error of the ephemeris satellite, and the error of the positioning information. Some examples are as follows:

[0045] If the moving speed of the terminal device is greater than a first speed threshold, the first parameter includes the positioning information of the terminal device and the ephemeris information of the service satellite; or, if the moving speed of the terminal device is less than a second speed threshold, the first parameter includes the ephemeris information of the service satellite; or, if the orbital altitude of the service satellite is lower than the first altitude threshold, the first parameter includes the ephemeris information of the service satellite; or, if the orbital altitude of the service satellite is higher than the second altitude threshold, the first parameter includes the positioning information of the terminal device; or, if the moving speed of the terminal device is greater than the first speed threshold and the orbital altitude of the service satellite is higher than the second altitude threshold, the first parameter includes the positioning information of the terminal device; or, if the moving speed of the terminal device is less than the second speed threshold and the orbital altitude of the service satellite is lower than the first altitude threshold, the first parameter includes the ephemeris information of the service satellite; or, if the error corresponding to the ephemeris information of the service satellite is less than the first error threshold, the first parameter includes the positioning information of the terminal device; or, if the error corresponding to the positioning information of the terminal device is less than the second error threshold, the first parameter includes the ephemeris information of the terminal device.

[0046] Optionally, the threshold in the above design may be indicated to the terminal device by the service satellite, or may be predefined or configured in the terminal device. For example, before determining the TA adjustment amount, the terminal device may also perform the following operations: receiving first information from the service satellite, where the first information is used to indicate one or more of the following: a first speed threshold, a second speed threshold, a first altitude threshold, a second altitude threshold, a first error threshold, and a second error threshold.

[0047] In the fifth aspect, the apparatus can be used to execute the method of the second aspect. The apparatus can be a terminal device, or the apparatus can be a component in the terminal device (for example, a chip, or a chip system, or a circuit), or can be a device that can be used in combination with the terminal device.

[0048] In one possible implementation, the communication device may include a module or unit corresponding to the method / operation / step / action described in the second aspect, and the module or unit may be a hardware circuit, or software, or a combination of a hardware circuit and software. In one possible implementation, the device may include a processing unit (also referred to as a processing module) and a communication unit (also referred to as a communication module), wherein the communication unit may be used to perform the functions of receiving and / or sending, and the processing unit may be used to perform the above-mentioned second aspect or any possible implementation method of the second aspect.

[0049] Taking the communication device including a communication module and a processing module as an example, the functions of each module can be understood as follows:

[0050] A communication module, configured to receive first information, wherein the first information indicates I moments at which a terminal device sends a random access sequence, wherein the interval between each two moments in the I moments is the same, and I is a positive integer greater than 1; and, sending a random access sequence at the i-th moment in the I moments, and receiving a second timing advance command TAC at the third moment; wherein the third moment is a moment between the i-th moment and the i+1-th moment, and i is a positive integer from 1 to I-1.

[0051] A processing module is used to determine a TA adjustment amount according to a second TAC; wherein the second timing advance amount is determined by the terminal device before a third moment.

[0052] The communication module is also used to communicate with the service satellite according to the TA adjustment amount.

[0053] In one possible design, the second TAC is the first TAC received by the terminal device after the i-th moment. Optionally, the effective time of the TA adjustment amount determined based on the second TAC is the time period between the third moment and the next TAC after receiving the second TAC.

[0054] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0055] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0056] in, T A is the timing advance determined based on the second TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specific The timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,common N is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0057] In one possible design, the communication module is also used to send second information to the service satellite before receiving the first information, where the second information is used to indicate the valid time of the positioning information of the terminal device, and the second information is used to determine the interval between every two moments in I moments.

[0058] In the sixth aspect, the apparatus can be used to execute the method of the third aspect. The apparatus may be a terminal device, or the apparatus may be a component in the terminal device (for example, a chip, or a chip system, or a circuit), or may be a device that can be used in conjunction with the terminal device.

[0059] In one possible implementation, the communication device may include a module or unit corresponding to the method / operation / step / action described in the third aspect, and the module or unit may be a hardware circuit, or software, or a hardware circuit combined with software. In one possible implementation, the device may include a processing unit (also referred to as a processing module) and a communication unit (also referred to as a communication module), wherein the communication unit may be used to perform the functions of receiving and / or sending, and the processing unit may be used to perform the third aspect or any possible implementation method of the third aspect.

[0060] Taking the communication device including a communication module and a processing module as an example, the functions of each module can be understood as follows:

[0061] The processing module is used to send second information to the serving satellite through the communication module when determining to update the first parameter, and the second information is used to request configuration information of the random access sequence; wherein the first parameter includes one or more of the following information: positioning information of the terminal device, ephemeris information of the serving satellite, and public timing advance TA information;

[0062] The processing module is also used to send a random access sequence through the communication module according to the configuration information of the received random access sequence; the terminal device receives a third timing advance command TAC and determines a TA adjustment amount according to the third TAC; wherein the third TAC is the first TAC received by the terminal device after sending the random access sequence.

[0063] The communication module is also used to communicate with the service satellite according to the TA adjustment amount.

[0064] In one possible design, TA adjusts the amount T TA Satisfies the following relationship:

[0065] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0066] in, T A is the timing advance determined based on the third TAC, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; N TA,UE-specificThe timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal equipment; N TA,common N is the timing advance associated with the public TA information; TA,offset is the preconfigured timing offset; T c The minimum time unit.

[0067] In the seventh aspect, the present application provides a communication device, comprising at least one processor and a memory; the memory is used to store computer programs or instructions, and when the device is running, the at least one processor executes the computer program or instructions to enable the communication device to perform a method as described in the first aspect or the various embodiments of the first aspect, or to perform a method as described in the second aspect or the various embodiments of the second aspect, or to perform a method as described in the third aspect or the various embodiments of the third aspect.

[0068] In an eighth aspect, the present application provides another communication device, comprising: a logic circuit and an input / output interface; wherein the input / output interface can be understood as an interface circuit, and the logic circuit can be used to run code instructions to execute the method of the above-mentioned first aspect or each embodiment of the first aspect, or to execute the method of the above-mentioned second aspect or each embodiment of the second aspect, or to execute the method of the above-mentioned third aspect or each embodiment of the third aspect.

[0069] In the ninth aspect, the present application also provides a computer-readable storage medium, which stores computer-readable instructions. When the computer-readable instructions are run on a computer, the computer executes a method as in the first aspect or any possible design of the first aspect, or executes a method as in the second aspect or any possible design of the second aspect, or executes a method as in the third aspect or any embodiment of the third aspect.

[0070] In a tenth aspect, the present application provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the method of the first aspect or each embodiment of the first aspect, or execute the method of the second aspect or each embodiment of the second aspect, or execute the method of the third aspect or each embodiment of the third aspect.

[0071] In an eleventh aspect, the present application provides a chip system, which includes a processor and may also include a memory, for implementing the method described in the first aspect or any possible design of the first aspect, or executing the method in the second aspect or any possible design of the second aspect, or executing the method in the third aspect or any possible design of the third aspect. The chip system may be composed of a chip, or may include a chip and other discrete devices.

[0072] In the twelfth aspect, the present application provides a communication system, comprising a terminal device and a satellite, the communication system being used to execute the method described in the first aspect or any possible design of the first aspect, or to execute the method described in the second aspect or any possible design of the second aspect, or to execute the method described in the third aspect or any possible design of the third aspect.

[0073] For the technical effects that can be achieved in the above-mentioned fourth to twelfth aspects, please refer to the description of the technical effects that can be achieved by the corresponding possible design schemes in the above-mentioned first or second aspects, and this application will not repeat them here. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 is a schematic diagram of a land communication system;

[0075] Figure 2 A schematic diagram of a non-terrestrial communication system provided in an embodiment of the present application;

[0076] Figure 3 A schematic diagram of the fifth generation (5G) satellite communication system architecture provided in an embodiment of the present application;

[0077] Figures 4 to 7 Schematic diagram of several TA determination methods provided in embodiments of the present application;

[0078] Figure 8 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0079] Fig. 9 A schematic diagram of the structure of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0080] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0081] The at least one (item) involved in the embodiments of the present application as follows indicates one (item) or more (items). More than one (item) refers to two (items) or more than two (items). "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. The character " / " generally indicates that the related objects before and after are in an "or" relationship. In addition, it should be understood that although the terms first, second, etc. may be used to describe each object in the embodiments of the present application, these objects should not be limited to these terms. These terms are only used to distinguish each object from each other.

[0082] The terms "including" and "having" and any variations thereof mentioned in the following description of the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes other steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. It should be noted that, in the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any method or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other methods or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete manner.

[0083] Figure 1 The architecture of a terrestrial network communication system is shown. The communication system 100 may include a network device 110 and terminal devices 101 to 106. It should be understood that the communication system 100 may include more or fewer network devices or terminal devices. The network device or terminal device may be hardware, or software divided from a functional point of view, or a combination of the above two. In addition, the terminal devices 104 to 106 may also form a communication system, for example, the terminal device 105 may send downlink data to the terminal device 104 or the terminal device 106. The network device and the terminal device may communicate through other devices or network elements. The network device 110 may send downlink data to the terminal devices 101 to 106, and may also receive uplink data sent by the terminal devices 101 to 106. Of course, the terminal devices 101 to 106 may also send uplink data to the network device 110, and may also receive downlink data sent by the network device 110.

[0084] The network device 110 is a node in a radio access network (RAN), which can also be called a base station, or a RAN node (or device). At present, some examples of access network devices are: gNB / NR-NB, transmission reception point (TRP), evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home evolved NodeB, or home Node B, HNB), base band unit (BBU), or wireless fidelity (Wifi) access point (AP), or network equipment in a 5G communication system, or network equipment in a possible future communication system. The network device 110 can also be other devices with network device functions, for example, the network device 110 can also be a device that functions as a network device in D2D communication. The network device 110 may also be a network device in a possible future communication system.

[0085] Terminal devices 101 to 106, which may also be referred to as UE, mobile station (MS), mobile terminal (MT), etc., are devices that provide voice or data connectivity to users, and may also be IoT devices. For example, terminal devices 101 to 106 include handheld devices and vehicle-mounted devices with wireless connection functions. At present, the terminal devices 101 to 106 may be: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MIDs), wearable devices (e.g., smart watches, smart bracelets, pedometers, etc.), vehicle-mounted devices (e.g., cars, bicycles, electric vehicles, airplanes, ships, trains, high-speed trains, etc.), virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, smart home devices (e.g., refrigerators, televisions, air conditioners, electric meters, etc.), smart robots, workshop equipment, wireless terminals in self-driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes, flying devices (e.g., smart robots, hot air balloons, drones, airplanes), etc. The terminal devices 101 to 106 may also be other devices having terminal functions. For example, the terminal devices 101 to 106 may also be devices that serve as terminal functions in D2D communications.

[0086] based on Figure 1 Based on the description of the terrestrial network communication system architecture shown in FIG. 1 , the TA determination method provided in the embodiment of the present application can be applied to non-terrestrial networks (NTN) communication systems. Figure 2As shown, the NTN communication system includes a satellite 201 and a terminal device 202. The explanation of the terminal device 202 can refer to the relevant description of the above-mentioned terminal devices 101 to 106. The satellite 201 can also be called a high-altitude platform, a high-altitude aircraft, or a satellite base station. In terms of the NTN communication system in connection with the terrestrial network communication system, the satellite 201 can be regarded as one or more network devices in the terrestrial network communication system architecture. The satellite 201 provides communication services to the terminal device 202, and the satellite 201 can also be connected to the core network device. The structure and functions of the satellite can also refer to the above-mentioned description of the network device. The communication method between the satellite 201 and the terminal device 202 can also refer to the above-mentioned Figure 1 The description in . I will not repeat it here.

[0087] Taking 5G as an example, a 5G satellite communication system architecture is as follows: Figure 3 As shown in the figure, ground terminal equipment accesses the network through the 5G new air interface, and the 5G base station is deployed on the satellite and connected to the ground core network through a wireless link. At the same time, there is a wireless link between satellites to complete the signaling interaction and user data transmission between base stations. Figure 3 The devices and interfaces in the are described as follows:

[0088] 5G core network: user access control, mobility management, session management, user security authentication, billing and other services. It consists of multiple functional units, which can be divided into functional entities of control plane and data plane. Access and mobility management unit (AMF) is responsible for user access management, security authentication, and mobility management. User plane function (UPF) is responsible for managing the transmission of user plane data, traffic statistics and other functions.

[0089] Ground station: responsible for forwarding signaling and business data between satellite base stations and 5G core network.

[0090] 5G New Air Interface: The wireless link between the terminal and the base station.

[0091] Xn interface: The interface between 5G base stations, mainly used for signaling interactions such as switching.

[0092] NG interface: The interface between the 5G base station and the 5G core network, which mainly interacts with the core network's NAS and other signaling, as well as the user's business data.

[0093] The network devices in the terrestrial network communication system and the satellites in the NTN communication system can be uniformly regarded as network devices. The device for realizing the function of the network device can be a network device; it can also be a device that can support the network device to realize the function, such as a chip system, which can be installed in the network device. When describing the technical solution provided by the embodiment of the present application below, the technical solution provided by the embodiment of the present application is described by taking the device for realizing the function of the network device as a satellite as an example. It can be understood that when the method provided by the embodiment of the present application is applied to the terrestrial network communication system, the actions performed by the satellite can be applied to the base station or network device for execution.

[0094] In the embodiment of the present application, the device for realizing the function of the terminal device may be a terminal device; or it may be a device capable of supporting the terminal device to realize the function, such as a chip system, which may be installed in the terminal device. In the embodiment of the present application, the chip system may be composed of a chip, or may include a chip and other discrete devices. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for realizing the function of the terminal device as a terminal or UE as an example.

[0095] In addition, the above-mentioned satellites may be geostationary satellites, non-geostationary satellites, artificial satellites, low-orbit satellites, medium-orbit satellites, and high-orbit satellites, etc., which are not specifically limited in the present application.

[0096] As described in the background technology, the TA adjustment value T used for communication between the terminal device and the service satellite in the related technology is TA It can be determined according to the following relationship (1):

[0097] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ; (1)

[0098] (a)N TA :When the terminal device sends a random access sequence or sends a physical random access channel (PRACH), N TA=0. For example, in a non-contention-based random access process, the serving satellite may indicate the configuration information of the random access sequence, such as the random access resource, through control signaling. Optionally, the control signaling may be a physical downlink control channel (PDCCH). Since the configuration information of the random access sequence is indicated in the PDCCH, the PDCCH may also be recorded as PDCCH ordered PRACH. The terminal device sends the random access sequence according to the random access resource indicated by the control signaling. At this time, N TA =0.

[0099] Further, after sending the random access sequence, the terminal device receives a random access response (RAR) message from the serving satellite, wherein the RAR message includes the TAC. The terminal device can select the N based on the TA corresponding to the TAC. TA Afterwards, each time the terminal receives a TAC, it determines the new N by accumulating the TA corresponding to the historical TAC. TA , denoted as N TA_new That is, it can be understood that, in the case of accumulated historical TAC, N in equation (1) TA Can be replaced by N TA_new The N TA_new It conforms to the following relationship (2):

[0100]

[0101] Among them, T A It can be understood as the timing advance determined according to the most recently received TAC; N TA_old It can be understood that when the TA adjustment amount was determined last time, N TA μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device, for example, μ can be a scaling factor of the subcarrier spacing relative to the reference subcarrier spacing. In addition, N TA or N TA_new It can be understood as the TA corresponding to the closed-loop TA adjustment mechanism.

[0102] (b)N TA,UE-specific The timing advance is determined based on the ephemeris information of the service satellite and the positioning information of the terminal device. TA,UE-specific It refers to the round-trip transmission delay from the terminal device to the service satellite, or the round-trip transmission delay of the service link. In addition, it can be understood that the ephemeris information of the service satellite and the positioning information of the terminal device will be updated in some communication scenarios. TAThe latest ephemeris information of the service satellite and the positioning information of the terminal device are input at the same time. Optionally, the positioning information of the terminal device may be the GNSS information of the terminal device, and the terminal device may update the GNSS information by itself; the updated ephemeris information of the service satellite may be indicated to the terminal device by the service satellite via broadcast.

[0103] (c)N TA,common The timing advance associated with the common TA.

[0104] The public TA refers to the round-trip transmission delay from the satellite to the reference point. The reference point can be located at the satellite, the ground station, or other locations such as a certain location on the service link from the satellite to the terminal device, or a certain location on the feeder circuit from the satellite to the ground station. This embodiment of the present application does not limit this. TA,UE-specific +N TA,common ” can be understood as the TA corresponding to the open-loop TA adjustment mechanism.

[0105] Optionally, the serving satellite may broadcast a public TA or parameters for determining a public TA, and the terminal device determines the public TA based on the received broadcast message, and determines the public TA based on the public TA and T c Determine N TA,common . T c is the minimum time unit, T c It can be pre-defined, or determined by negotiation between the terminal device and the access network device, or configured to the terminal device by the access network device.

[0106] For example, to avoid the terminal device from frequently monitoring broadcast messages, the parameters of the public TA generally include one or more of the public TA, TA change rate, second-order TA change rate, third-order TA change rate and other high-order change rates. The terminal device can estimate the public TA within a certain time range based on these parameters.

[0107] (d)N TA,offset is the preconfigured timing offset, for example, N TA,offset The value of is related to the communication mode between the terminal device and the service satellite. The communication mode between the terminal device and the service satellite can be time division duplex (TDD) or frequency division duplex (FDD).

[0108] It can be understood that the above equations (1) and (2) are used as examples for determining the TA adjustment amount. In actual application, the equations can be appropriately adjusted, such as by modifying some parameters of the equations. The embodiments of the present application do not limit this.

[0109] Applying the above TA adjustment mechanism to satellite communications, when the terminal receives TAC, N TA_old It will be accumulated in the TA adjustment amount determined by the terminal device to compensate for the errors in the ephemeris information, public TA information or positioning information; and when the terminal updates the position or ephemeris, it can compensate for the errors in the ephemeris information, public TA information or positioning information. If these two error compensations are performed at the same time, the ephemeris information, public TA information or GNSS errors determined by the terminal will increase, resulting in TA error jumps, and thus causing the determined TA adjustment amount to be inaccurate. An example is as follows:

[0110] T0: The terminal device monitors the ephemeris information or public TA information and updates the GNSS;

[0111] T1 moment: the uplink signal sent by the terminal device to the network side (such as the service satellite);

[0112] Time T2: The terminal device receives the TAC and adjusts the TA adjustment amount based on the TAC. The TAC is determined by the network side after estimating the uplink signal initiated by the terminal device at time T1. The TAC can represent the error compensation for the GNSS, ephemeris information, or public TA information at time T1.

[0113] At T3: The terminal device compensates for the errors of these parameters through the update of ephemeris information, GNSS or public TA information. However, the accumulated N TA_old If it still exists, the determined TA adjustment amount will be inaccurate.

[0114] Considering the above situation, the present application provides some TA determination methods to reduce the error jump when determining the TA adjustment amount, while ensuring the accuracy of the TA adjustment amount.

[0115] like Figure 4 The first TA determination method is illustrated, and the method mainly includes the following process.

[0116] S401, a service satellite sends a first timing advance command TAC to a terminal device, and the terminal device receives the first TAC at a first moment.

[0117] The terminal device receives at least one TAC before receiving the first TAC. The time of one TAC before the first TAC received by the terminal device is recorded as the second time, and the time period between the second time and the first time is recorded as the first time period.

[0118] If one or more of the terminal device's positioning information, the service satellite's ephemeris information, and the public timing advance TA is updated within the first time period, then the terminal device determines the TA adjustment amount based on the first TAC, which can be specifically performed with reference to S402. If one or more of the terminal device's positioning information, the service satellite's ephemeris information, and the public timing advance TA is not updated within the first time period, the TA adjustment amount is determined according to equations (1) and (2).

[0119] S402: The terminal device determines a TA adjustment amount according to components of a first timing advance amount and the first TAC.

[0120] The first timing advance is determined by the terminal device at the second moment. For example, the terminal device may determine the first timing advance according to the above equation (2) at the second moment. TA_new Indicates a first timing advance, the first timing advance being based on N before the second moment TA_old and the TA corresponding to the TAC received at the second time. The component of the first timing advance may be zero or the percentage of the component of the first timing advance to the first timing advance is less than 100%, such as preconfigured to 40% or other values.

[0121] Specifically, the terminal device can determine the TA adjustment amount through the following equations (3) and (4).

[0122] T TA =(N TA_new +N TA,UE-specific +N TA,common +N TA,offset )×T c ; (3)

[0123] Among them, N TA,UE-specific 、N TA,common 、N TA,offset and T c This can be understood by referring to the explanation in relational equation (1), and will not be described in detail in the present embodiment. TA_new It can be understood as the N determined by the terminal device at the first moment. TA , the N TA_new The following relationship (4) is satisfied.

[0124]

[0125] The N TA_old is the first timing advance, the α×N TA_old represents the component of the first timing advance, 0≤α<1, the T Ais the timing advance determined based on the first TAC, and μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device. Optionally, when α is equal to 0, the relationship (4) can also be replaced by: or, Optionally, when α is equal to 0, S402 can also be understood as the terminal device determining the TA adjustment amount according to the first TAC, and the first timing advance amount is not considered when determining the TA adjustment amount according to the first TAC, N TA_old =0.

[0126] For ease of description, the embodiment of the present application uses a first parameter to indicate information updated within a first time period. Figure 4 Before S401, it is indicated that the first parameter is updated within the first time period, or it can be understood that: the first parameter includes one or more information of the positioning information of the terminal device, the ephemeris information of the service satellite, and the public timing advance TA.

[0127] Optionally, corresponding to different communication scenarios, the content included in the first parameter may be different. Examples of some scenarios are as follows:

[0128] Scenario 1, in the scenario where the service satellite is a geostationary earth orbit (GEO) satellite, it mainly includes error compensation corresponding to the update of the positioning information of the terminal device, so the first parameter may only include the positioning information of the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after updating the positioning information.

[0129] Scenario 2, in which the service satellite is a low earth orbit (LEO) satellite and the terminal device is in a stationary state, mainly includes error compensation for updating the ephemeris information of the service satellite, so the first parameter may only include the ephemeris information of the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after obtaining the updated ephemeris information of the service satellite.

[0130] Scenario 3, in the scenario where the service satellite is a low-orbit LEO satellite and the terminal device is in a mobile state, it may include error compensation for the ephemeris information of the service satellite and the positioning information update of the terminal device. The terminal device can determine that the first parameter includes one or more of the ephemeris information of the service satellite and the positioning information of the terminal device based on parameters related to the positioning information (such as the moving speed, moving range, positioning accuracy, and positioning error of the terminal device) and the ephemeris information of the service satellite obtained (such as the orbital height of the service satellite, the accuracy information of the ephemeris, the effective time of the ephemeris, and the error of the ephemeris). Some examples are as follows:

[0131] Example 1: When the moving speed of the terminal device is greater than a first speed threshold, or the accuracy of the estimated positioning information of the terminal device is less than a first accuracy threshold, the first parameter includes the positioning information of the terminal device and the ephemeris information of the service satellite. The first speed threshold may be predefined or configured, or the service satellite indicates the first speed threshold to the terminal device; the first accuracy threshold may be predefined or configured, or the service satellite indicates the first accuracy threshold to the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after obtaining the updated ephemeris information of the service satellite and the updated positioning information.

[0132] Example 2: When the moving speed of the terminal device is less than the second speed threshold, or the accuracy of the terminal device's estimated positioning information is greater than the second accuracy threshold, it indicates that the error compensation for updating the positioning information of the terminal device is small. In this case, the first parameter may only include the ephemeris information of the service satellite. The second speed threshold may be predefined or configured, or the service satellite indicates the first speed threshold to the terminal device. The second speed threshold is less than or equal to the first speed threshold. The second accuracy threshold may be predefined or configured, or the service satellite indicates the first accuracy threshold to the terminal device. The second accuracy threshold is greater than or equal to the first accuracy threshold. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after obtaining the updated ephemeris information of the service satellite.

[0133] Example 3, when the orbital altitude of the service satellite is lower than a first altitude threshold, the first parameter includes the ephemeris information of the service satellite. The first altitude threshold may be predefined or configured, or the service satellite indicates the first altitude threshold to the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after acquiring the updated ephemeris information of the service satellite.

[0134] Example 4: When the orbital altitude of the service satellite is higher than a second altitude threshold, the first parameter includes the positioning information of the terminal device. The second altitude threshold may be predefined or configured, or the service satellite indicates the second altitude threshold to the terminal device. The second altitude threshold is greater than or equal to the first altitude threshold. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after updating the positioning information.

[0135] Example 5: When the moving speed of the terminal device is greater than a first speed threshold and the orbital altitude of the service satellite is higher than a second altitude threshold, the first parameter includes the positioning information of the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after updating the positioning information.

[0136] Example 6: When the moving speed of the terminal device is less than the second speed threshold and the orbital altitude of the service satellite is lower than the first altitude threshold, the first parameter includes the ephemeris information of the service satellite. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after obtaining the updated ephemeris information of the service satellite.

[0137] Example 7: When the error corresponding to the ephemeris information of the serving satellite is less than a first error threshold, the first parameter includes the positioning information of the terminal device. Optionally, the first error threshold may be predefined or configured, or the serving satellite indicates the first error threshold to the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after updating the positioning information.

[0138] Among them, the error corresponding to the ephemeris information mainly includes the initial error of the ephemeris indicated by the service satellite and the derived error of the ephemeris derived by the terminal device. In a possible implementation, the accuracy of the ephemeris derived by the terminal device is high, so that the derived error of the ephemeris is small, and it is possible to achieve that the error corresponding to the ephemeris information is less than the first error threshold. Optionally, the terminal device can also report the accuracy of the derived ephemeris or the error model used to determine the derived error to the service satellite. The service satellite can configure the validity period or update period of the ephemeris information to the terminal device based on the information reported by the terminal device. The terminal device can then determine the time to read the ephemeris information broadcast by the service satellite based on the validity period or update period of the ephemeris information, thereby reducing the impact of the terminal device reading the ephemeris information or updating the positioning information on the determination of the TA adjustment amount.

[0139] Example 8: When the error corresponding to the positioning information of the terminal device is less than a second error threshold, the first parameter includes the ephemeris information of the terminal device. Optionally, the second error threshold may be predefined or configured, or the service satellite indicates the second error threshold to the terminal device. In specific implementation, the terminal device may determine the TA adjustment amount in accordance with S402 when receiving the first TAC after acquiring the updated ephemeris information of the service satellite.

[0140] The terminal device can determine the accuracy and error of the positioning information by itself. Optionally, the terminal device can also report the error (which can be a specific value or an error range) corresponding to the positioning information to the service satellite.

[0141] Furthermore, the terminal device may also perform step S403:

[0142] S403: The terminal device communicates with the service satellite according to the TA adjustment amount.

[0143] Specifically, the TA adjustment amount corresponds to the first TAC received by the terminal device in S401, and the terminal device can communicate with the serving satellite according to the TA adjustment amount until the next TAC is received and the TA adjustment amount is updated.

[0144] The above method provided in the embodiment of the present application uses the positioning information update of the terminal device and / or the ephemeris update of the service satellite as trigger conditions in a specific satellite communication scenario, reduces the error compensation of the closed-loop TA adjustment mechanism part, can reduce the error jump when determining the TA adjustment amount, and at the same time can ensure the accuracy of the TA adjustment amount.

[0145] like Figure 5 The second TA determination method is illustrated, and the method mainly includes the following process.

[0146] S501, a service satellite sends first information to a terminal device.

[0147] The first information indicates periodic information of a random sequence sent by the terminal device. For example, the first information indicates I times when the terminal device sends a random access sequence, where the interval between every two times in the I times is the same, and I is a positive integer greater than 1.

[0148] In one possible implementation, the terminal device can report the valid time of the positioning information to the service satellite, and the service satellite configures the periodic information of the aforementioned random access sequence according to the valid time of the positioning information of the terminal device, for example, the interval between every two moments in I moments is less than or equal to the valid time of the positioning information of the terminal device.

[0149] S502: The terminal device sends a random access sequence at the i-th moment among the I moments, and receives a second timing advance command TAC from the serving satellite at the third moment.

[0150] The third moment is a moment between the i-th moment and the i+1-th moment, and i is a positive integer from 1 to I-1. Optionally, the second TAC is the first TAC received by the terminal device after the i-th moment.

[0151] In addition, it can be understood that the service satellite can periodically send PDCCH (such as PDCCH order PARCH) to trigger the terminal device to send a random access sequence. For example, the service satellite sends a PDCCH order PARCH in the time period between the i-1th moment and the i-th moment, which can trigger the terminal device to send a random access sequence at the i-th moment.

[0152] S503: The terminal device determines a TA adjustment amount according to the second TAC.

[0153] Corresponding to the description in formula (1), it can be understood that when the terminal device sends a random access sequence at the i-th time, N TA Therefore, when the terminal device receives the second TAC to determine the TA adjustment amount, it will not accumulate the TA corresponding to the historical TAC.

[0154] Specifically, the terminal device determines the TA adjustment amount T according to the second TAC TA The following relations (5) and (6) are satisfied:

[0155] T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ;

[0156] Among them, N TA,UE-specific 、N TA,common 、N TA,offset and T c This can be understood by referring to the explanation in relational equation (1), and will not be described in detail in the present embodiment. TA is the timing advance determined by the terminal device based on the second TAC, wherein N TA The following relationship (6) is satisfied.

[0157]

[0158] Herein, μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device.

[0159] S504: The terminal device communicates with the service satellite according to the TA adjustment amount.

[0160] Specifically, the TA adjustment amount corresponds to the second TAC received by the terminal device in S502, and the terminal device can communicate with the serving satellite according to the TA adjustment amount until the next TAC of the second TAC is received and the TA adjustment amount is updated.

[0161] The above method provided in the embodiment of the present application utilizes the characteristic that the historical TAC is accumulated to zero when the terminal device sends a random access sequence, configures the periodic sending of the random access sequence, and realizes the periodic multiple reduction of the error compensation of the closed-loop TA adjustment mechanism part, which can reduce the error jump when determining the TA adjustment amount, and at the same time ensure the accuracy of the TA adjustment amount. For example, for the communication scenario of GEO satellites, TA is mainly caused by the error of the positioning information (GNSS information) of the terminal device. The service satellite configures enough PDCCH ordered PRACH to correct the TA error accumulated by TAC according to the effective duration of the positioning information of the terminal device. For the LEO scenario, the TA error is mainly caused by the initial error of the service satellite's ephemeris. The service satellite can correct the TA error accumulated by TAC by sending enough PDCCH ordered PRACH.

[0162] like Figure 6 The third TA determination method is illustrated, and the method includes the following process.

[0163] S601: When the terminal device determines to update the first parameter, the terminal device sends second information to the service satellite.

[0164] The first parameter may be one or more of the following information: positioning information of the terminal device, ephemeris information of the serving satellite, and public timing advance TA information. The second information is used to request configuration information of the random access sequence, for example, the second information is used to request the serving satellite to send a PDCCH order PRACH.

[0165] Optionally, the second information sent by the terminal device may be an uplink (UL)-medium access control (MAC)-control element (CE) signaling, referred to as UL MAC CE. The terminal device may also implement an update operation on the first parameter through UL MAC CE, that is, the terminal device may update the first parameter after sending UL MAC CE. In such a design, the service satellite configures PRACH only at the request of the terminal device, which can save PDCCH / PRACH resources.

[0166] Accordingly, if the terminal device receives configuration information of the random access sequence such as PDCCH order PRACH, the random access sequence is sent to the serving satellite, that is, the terminal device performs S602 after S601. If the terminal device does not receive configuration information of the random access sequence such as PDCCH order PRACH, the terminal device does not send the random access sequence to the serving satellite.

[0167] S602, the terminal device receives configuration information of a random access sequence and sends a random access sequence.

[0168] Correspondingly, after receiving the random access sequence, the serving satellite sends a TAC to the terminal device through a RAR message, and the TAC is recorded as the third TAC. For the terminal device, the third TAC is the first TAC received by the terminal device after sending the random access sequence. Specifically, the terminal device may perform the following step S603 after performing S602.

[0169] S603: The terminal device receives a third TAC and determines a TA adjustment amount according to the third TAC.

[0170] Corresponding to the description in formula (1), it can be understood that when the terminal device sends a random access sequence, N TA Therefore, when the terminal device receives the third TAC to determine the TA adjustment amount, it will not accumulate the TA corresponding to the historical TAC.

[0171] Specifically, the terminal device can determine the TA adjustment amount T according to the third TAC according to equations (5) and (6). TA It can be understood that in S603, T in equation (6) A Substituted is the timing advance corresponding to the third TAC, that is, the terminal device calculates the timing advance T corresponding to the third TAC according to equation (6). A , determine N in equation (5) TA , and then determine the TA adjustment amount based on equation (5).

[0172] Furthermore, after executing S603, the terminal device may further execute step S604:

[0173] S604: The terminal device communicates with the service satellite according to the TA adjustment amount.

[0174] Specifically, the TA adjustment amount corresponds to the third TAC received by the terminal device in S603. The terminal device can communicate with the service satellite according to the TA adjustment amount until the next TAC of the third TAC is received and the TA adjustment amount is updated.

[0175] In the above method provided in the embodiment of the present application, the terminal device utilizes the characteristic that the historical TAC accumulates to zero when sending a random access sequence, and requests the network side to send a random access sequence during the positioning information or ephemeris information update process to reduce the error compensation of the closed-loop TA adjustment mechanism part, which can reduce the error jump when determining the TA adjustment amount, and at the same time ensure the accuracy of the TA adjustment amount.

[0176] like Figure 7 The fourth TA determination method is illustrated, which is mainly applied to communication scenarios where the terminal device is in a mobile state. The method includes the following process.

[0177] S701, the satellite sends third information to the terminal device.

[0178] The third information indicates a requirement for the mobile state of the terminal device, such as the third information indicates a first condition that the mobile state of the terminal device needs to satisfy. Optionally, the satellite may send the third information by broadcasting, and the terminal device may obtain the third information by monitoring the broadcast message. The satellite may be a LEO satellite or a GEO satellite.

[0179] Specifically, the movement state of the terminal device may include parameters such as the movement speed of the terminal device, the movement range of the terminal device within a unit time, and the movement direction of the terminal device.

[0180] In a first possible implementation, the first condition indicated by the third information is that the moving speed of the terminal device is less than or equal to the third speed threshold, and the third information may include the third speed threshold. For example, the satellite may determine the upper limit of the moving speed of the terminal device supported by the current satellite according to the orbital altitude, that is, determine the third speed threshold. For another example, the satellite may determine the third speed threshold according to the orbital altitude and the elevation angle information from the terminal device to the satellite. It is understandable that different elevation angle information corresponds to different values ​​of the third speed threshold.

[0181] In a second possible implementation, the first condition indicated by the third information is that the moving speed of the terminal device belongs to the first speed range, and the third information may include the first speed range. For example, the satellite may determine the moving speed range of the terminal device supported by the current satellite based on the orbital altitude, that is, determine the first speed range. For another example, the satellite may determine the first speed range based on the orbital altitude and the elevation angle information from the terminal device to the satellite. It is understandable that different elevation angle information corresponds to different values ​​of the first speed range.

[0182] In a third possible implementation, the first condition indicated by the third information is that the movement range of the terminal device in a unit time is less than or equal to the first movement range, and the third information may include the first movement range. For example, the satellite can determine the upper limit of the movement range of the terminal device supported by the current satellite in a unit time according to the orbital altitude, that is, determine the first movement range. For another example, the satellite can determine the first movement range based on the orbital altitude and the elevation angle information from the terminal device to the satellite. It can be understood that different elevation angle information corresponds to different values ​​of the first movement range.

[0183] Accordingly, after receiving the third information, the terminal device can determine whether its own mobile state meets the first condition indicated by the third information according to the positioning information. If the mobile state meets the first condition, the terminal device initiates random access to the satellite, and continues to maintain the mobile state meeting the first condition during the communication process after the random access; if the mobile state does not meet the first condition, the terminal device does not initiate random access to the satellite. Exemplarily, Figure 7 The situation where the moving state meets the first condition is illustrated through S702 and S703.

[0184] S702: The terminal device determines, based on the positioning information, that the movement state of the terminal device meets the first condition indicated by the third information.

[0185] S703, the terminal device initiates random access to the satellite.

[0186] For example, the terminal device may send a random access sequence on the random access resource configured by the satellite, and the satellite may return a RAR message including the TAC. The terminal device may determine the TA adjustment amount used for communicating with the satellite according to the scheme described in equation (1). This embodiment of the present application will not be described in detail.

[0187] The above method provided in the embodiment of the present application is applied to the communication scenario of the mobile terminal. By controlling the moving speed or moving range of the terminal device, the error compensation for updating the positioning information is reduced, that is, the error compensation of the open-loop TA adjustment mechanism is reduced. This can reduce the error jump when determining the TA adjustment amount, and at the same time ensure the accuracy of the TA adjustment amount.

[0188] Based on the same idea, see Figure 8 , the embodiment of the present application provides a communication device 800, which includes a processing module 801 and a communication module 802. The communication device 800 can be a terminal device, or a communication device applied to a terminal device or used in combination with a terminal device, and capable of implementing a communication method executed on the terminal device side; or, the communication device 800 can be a network device (such as a service satellite of a terminal device), or a communication device applied to a network device or used in combination with a network device, and capable of implementing a communication method executed on the network device side.

[0189] The communication module may also be referred to as a transceiver module, a transceiver, a transceiver, or a transceiver device, etc. The processing module may also be referred to as a processor, a processing board, a processing unit, or a processing device, etc. Optionally, the communication module is used to perform the sending operation and the receiving operation on the terminal device side or the network device side in the above method, and the device used to implement the receiving function in the communication module may be regarded as a receiving unit, and the device used to implement the sending function in the communication module may be regarded as a sending unit, that is, the communication module includes a receiving unit and a sending unit.

[0190] When the communication device 800 is applied to a terminal device, the processing module 801 can be used to implement Figures 4 to 7 The processing function of the terminal device in the embodiment shown, the communication module 802 can be used to implement Figures 4 to 7 The sending and receiving functions of the terminal device in the illustrated embodiment.

[0191] When the communication device 800 is applied to a network device, the processing module 801 can be used to implement Figures 4 to 7 In the embodiment shown, the communication module 802 can be used to implement the processing function of the network device. Figures 4 to 7 The sending and receiving functions of the network device in the illustrated embodiment.

[0192] In addition, it should be noted that the aforementioned communication module and / or processing module can be implemented through a virtual module, for example, the processing module can be implemented through a software function unit or a virtual device, and the communication module can be implemented through a software function or a virtual device. Alternatively, the processing module or the communication module can also be implemented through a physical device, for example, if the communication device is implemented using a chip / chip circuit, the communication module can be an input-output circuit and / or a communication interface, performing input operations (corresponding to the aforementioned receiving operations) and output operations (corresponding to the aforementioned sending operations); the processing module is an integrated processor or microprocessor or integrated circuit.

[0193] The division of modules in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional module in each embodiment of the present application may be integrated into a processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0194] Based on the same technical concept, the embodiment of the present application also provides a communication device 900. For example, the communication device 900 can be a chip or a chip system. Optionally, in the embodiment of the present application, the chip system can be composed of chips, or can include chips and other discrete devices.

[0195] The communication device 900 can be used to implement the functions of any network element in the communication system described in the aforementioned embodiments. The communication device 900 may include at least one processor 910, which is coupled to a memory. Optionally, the memory may be located within the communication device, the memory may be integrated with the processor, or the memory may be located outside the communication device. For example, the communication device 900 may also include at least one memory 920. The memory 920 stores the necessary computer programs, computer programs or instructions and / or data for implementing any of the above embodiments; the processor 910 may execute the computer program stored in the memory 920 to complete the method in any of the above embodiments.

[0196] The communication device 900 may also include a communication interface 930, and the communication device 900 may exchange information with other devices through the communication interface 930. Exemplarily, the communication interface 930 may be a transceiver, a circuit, a bus, a module, a pin, or other types of communication interfaces. When the communication device 900 is a chip-type device or circuit, the communication interface 930 in the communication device 900 may also be an input-output circuit, which may input information (or receive information) and output information (or send information), and the processor may be an integrated processor or a microprocessor or an integrated circuit or a logic circuit, and the processor may determine the output information based on the input information.

[0197] The coupling in the embodiment of the present application is an indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, and is used for information exchange between devices, units or modules. The processor 910 may cooperate with the memory 920 and the communication interface 930. The specific connection medium between the above-mentioned processor 910, memory 920 and communication interface 930 is not limited in the embodiment of the present application.

[0198] Optional, see Fig. 9 The processor 910, the memory 920 and the communication interface 930 are connected to each other via a bus 940. The bus 940 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig. 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0199] In the embodiments of the present application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0200] In the embodiment of the present application, the memory may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), such as a random access memory (RAM). The memory is any other medium that can be used to carry or store a desired program code in the form of an instruction or data structure and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present application may also be a circuit or any other device that can implement a storage function, for storing program instructions and / or data.

[0201] In a possible implementation, the communication device 900 can be applied to a network device (such as a service satellite of a terminal device). Specifically, the communication device 900 can be a network device, or a device that can support a network device and implement the functions of the network device in any of the above-mentioned embodiments. The memory 920 stores a computer program (or instruction) and / or data that implements the functions of the network device in any of the above-mentioned embodiments. The processor 910 can execute the computer program stored in the memory 920 to complete the method executed by the network device in any of the above-mentioned embodiments. Applied to a network device, the communication interface in the communication device 900 can be used to interact with a terminal device, send information to the terminal device, or receive information from the terminal device.

[0202] In another possible implementation, the communication device 900 can be applied to a terminal device. Specifically, the communication device 900 can be a terminal device, or a device that can support a terminal device and implement the functions of the terminal device in any of the above-mentioned embodiments. The memory 920 stores a computer program (or instruction) and / or data that implements the functions of the terminal device in any of the above-mentioned embodiments. The processor 910 can execute the computer program stored in the memory 920 to complete the method executed by the terminal device in any of the above-mentioned embodiments. Applied to a terminal device, the communication interface in the communication device 900 can be used to interact with a network device, send information to the network device, or receive information from the network device.

[0203] Since the communication device 900 provided in this embodiment can be applied to a network device to complete the method executed by the above network device, or applied to a terminal device to complete the method executed by the terminal device, the technical effects that can be obtained can refer to the above method examples and will not be repeated here.

[0204] Based on the above embodiments, the present application provides a communication system, including a network device and a terminal device, wherein the network device and the terminal device can implement Figure 3 , Figure 5 or Figure 6 The method provided in the illustrated embodiment.

[0205] The technical solution provided in the embodiment of the present application can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a terminal device, a network device or other programmable device. The computer instructions may 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 may be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or a data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium, etc.

[0206] In the embodiments of the present application, under the premise of no logical contradiction, the embodiments may reference each other, for example, the methods and / or terms between method embodiments may reference each other, for example, the functions and / or terms between device embodiments may reference each other, for example, the functions and / or terms between device embodiments and method embodiments may reference each other.

[0207] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the scope of the embodiments of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the embodiments of the present application and their equivalents, the embodiments of the present application are also intended to include these modifications and variations.

Claims

1. A method for determining a timing advance TA, characterized in that: include: The terminal device receives a first timing advance command TAC at a first moment; If the first parameter is updated within a first time period before the first moment, the terminal device determines a TA adjustment amount according to a component of a first timing advance and the first TAC; wherein the first timing advance is determined by the terminal device at the second moment, and the first time period is a time period from the second moment to the first moment; the first parameter includes one or more of the following information: positioning information of the terminal device, ephemeris information of a service satellite, and a public timing advance TA; The terminal device communicates with the serving satellite according to the TA adjustment amount.

2. The method according to claim 1, characterized in that The service satellite is a geostationary orbit GEO satellite, and the first parameter includes positioning information of the terminal device.

3. The method according to claim 1, characterized in that The service satellite is a low-orbit LEO satellite, the terminal device is in a stationary state, and the first parameter includes ephemeris information of the service satellite.

4. The method according to claim 1, characterized in that The service satellite is a low-orbit LEO satellite, the terminal device is in a mobile state, and the first parameter includes the positioning information of the terminal device and / or the ephemeris information of the service satellite.

5. The method according to claim 4, characterized in that: If the moving speed of the terminal device is greater than a first speed threshold, the first parameter includes positioning information of the terminal device and ephemeris information of the service satellite; or, If the moving speed of the terminal device is less than a second speed threshold, the first parameter includes ephemeris information of the service satellite; or, If the orbital altitude of the service satellite is lower than a first altitude threshold, the first parameter includes ephemeris information of the service satellite; or, If the orbital altitude of the service satellite is higher than a second altitude threshold, the first parameter includes positioning information of the terminal device; or, If the moving speed of the terminal device is greater than a first speed threshold, and the orbital altitude of the service satellite is higher than a second altitude threshold, the first parameter includes positioning information of the terminal device; or, If the moving speed of the terminal device is less than a second speed threshold, and the orbital altitude of the service satellite is lower than a first altitude threshold, the first parameter includes ephemeris information of the service satellite; or, If the error corresponding to the ephemeris information of the service satellite is less than a first error threshold, the first parameter includes positioning information of the terminal device; or, If the error corresponding to the positioning information of the terminal device is less than a second error threshold, the first parameter includes the ephemeris information of the terminal device.

6. The method according to claim 5, characterized in that Before determining the TA adjustment amount, it also includes: First information is received from the serving satellite, where the first information is used to indicate one or more of the following: the first speed threshold, the second speed threshold, the first altitude threshold, the second altitude threshold, the first error threshold, and the second error threshold.

7. The method according to any one of claims 1 to 6, characterized in that: The TA adjustment amount T TA Satisfies the following relationship: T TA =(N TA_new +N TA,UE-specific +N TA,common +N TA,offset )×T c ; Among them, the The N TA_old is the first timing advance, the α×N TA_old represents the component of the first timing advance, 0≤α<1, the T A is a timing advance determined based on the first TAC, and μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; The N TA,UE-specific is a timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal device; the N TA,common is the timing advance associated with the public TA information; the N TA,offset is the preconfigured timing offset; T c The minimum time unit.

8. A method for determining a timing advance TA, characterized in that: include: First information received by a terminal device, the first information indicating I moments at which the terminal device sends a random access sequence, the interval between every two moments in the I moments being the same, and I being a positive integer greater than 1; The terminal device sends a random access sequence at the i-th moment among the I moments, and receives a second timing advance command TAC at a third moment; wherein the third moment is a moment between the i-th moment and the i+1-th moment, and i is a positive integer from 1 to I-1; The terminal device determines a TA adjustment amount according to the second TAC; wherein the second timing advance amount is determined by the terminal device before the third moment; The terminal device communicates with the serving satellite according to the TA adjustment amount.

9. The method according to claim 8, characterized in that The second TAC is the first TAC received by the terminal device after the i-th moment.

10. The method according to claim 8 or 9, characterized in that The TA adjustment amount T TA Satisfies the following relationship: T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ; Among them, the The T A is a timing advance determined based on the second TAC, and μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; The N TA,UE-specific is a timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal device; the N TA,common is the timing advance associated with the public TA information; the N TA,offset is the preconfigured timing offset; T c The minimum time unit.

11. The method according to any one of claims 8 to 10, characterized in that Before the terminal device receives the first information, the method further includes: The terminal device sends second information to the service satellite, where the second information is used to indicate the valid time of the positioning information of the terminal device, and the second information is used to determine the interval between every two moments in the I moments.

12. A method for determining a timing advance TA, characterized in that: include: When the terminal device determines to update the first parameter, the terminal device sends second information to the serving satellite, where the second information is used to request configuration information of the random access sequence; wherein the first parameter includes one or more of the following information: positioning information of the terminal device, ephemeris information of the serving satellite, and public timing advance TA information; The terminal device sends a random access sequence according to the received configuration information of the random access sequence; The terminal device receives a third timing advance command TAC, and determines a TA adjustment amount according to the third TAC; wherein the third TAC is the first TAC received by the terminal device after sending a random access sequence; The terminal device communicates with the serving satellite according to the TA adjustment amount.

13. The method according to claim 12, characterized in that The TA adjustment amount T TA Satisfies the following relationship: T TA =(N TA +N TA,UE-specific +N TA,common +N TA,offset )×T c ; Among them, the The T A is a timing advance determined based on the third TAC, and μ is a coefficient determined based on the subcarrier spacing corresponding to the terminal device; The N TA,UE-specific is a timing advance determined based on the ephemeris information of the service satellite and the positioning information of the terminal device; the N TA,common is the timing advance associated with the public TA information; the N TA,offset is the preconfigured timing offset; T c The minimum time unit.

14. A communication device, characterized in that: The method comprises a module for executing the method according to any one of claims 1 to 7, or a module for executing the method according to any one of claims 8 to 11, or a module for executing the method according to any one of claims 12 to 13.

15. A communication device, characterized in that: include: at least one processor and memory; The memory is used to store computer programs or instructions; The at least one processor is configured to execute the computer program or instructions to implement the method according to any one of claims 1 to 7, or the method according to any one of claims 8 to 11, or the method according to any one of claims 12 to 13.

16. A communication device, characterized in that: include: Logic circuits and input-output interfaces; The input and output interface is used to communicate with modules outside the communication device; The logic circuit is used to execute a computer program to enable the communication device to execute the method according to any one of claims 1 to 7, or the method according to any one of claims 8 to 11, or the method according to any one of claims 12 to 13.

17. A communication system, characterized in that: The communication system includes a terminal device and a satellite, wherein the terminal device is used to execute the method as described in any one of claims 1 to 7, or to execute the method as described in any one of claims 8 to 11, or to execute the method as described in any one of claims 12 to 13; and the satellite is used to communicate with the terminal.

18. A computer-readable storage medium, characterized in that: The storage medium stores a computer program or an instruction, and when the computer program or the instruction is executed by the communication device, the method according to any one of claims 1 to 13 is implemented.

Images