RU2798043C2 - Method and apparatus for determining ta for terminal device - Google Patents

Abstract

FIELD: communications.

SUBSTANCE: technical result consists in providing the ability to adjust the timing advance (TA) by the terminal device when the movement of the device is caused by both the terminal device and the satellite base station. After receiving the TA adjustment parameter sent by the access network device and determining that the TA of the terminal device needs to be adjusted, the terminal device determines the TA scaling factor, the subcarrier spacing parameter, and the first TA to jointly adjust the first TA to obtain the second TA. The TA adjustment parameter k is added when the terminal determines the second TA so that the TA adjustment range is larger. The TA may be used to determine the TA of a terminal when the terminal communicates with a satellite base station.

EFFECT: ability to adjust the timing advance (TA) by the terminal device when the movement of the device is caused by both the terminal device and the satellite base station.

18 cl, 16 dwg

Description

[0001] The present application claims priority based on Chinese Patent Application No. 2019103566536 filed with the National Intellectual Property Office of China on April 29, 2019 and entitled "TA DETERMINING METHOD AND APPARATUS FOR TERMINAL DEVICE", which is hereby incorporated by reference in its entirety.

FIELD OF TECHNOLOGY

[0002] This application relates to the field of communications and, in particular, to a method and apparatus for determining the timing advance (timing advance, TA) for the terminal device, and the system.

BACKGROUND OF THE INVENTION

[0003] When a terminal device communicates with an access network device (e.g., a base station), if the terminal device is far away from the access network device, there is a relatively large transmission delay when the terminal device sends uplink data to the access network device . Therefore, the access network device establishes a timing advance (TA) of the terminal device. Thus, the terminal device can obtain, using TA, a negative offset between the first time when the terminal device receives downlink communication data of the access network device and the second time when the terminal device sends uplink communication data to the network device access. Therefore, the terminal can send the uplink communication data to the access network device in advance based on the TA to reduce the transmission delay of the uplink communication data.

[0004] In the tag random access process, the access network device determines the TA of the tag based on the random access preamble sent by the tag, and sends an initial TA parameter to the tag using the TAC field. Therefore, the terminal can determine the TA based on the initial TA parameter. After the terminal device performs random access for the mobility of the terminal device, the access network device determines, by measuring the uplink communication data of the terminal device, to adjust the TA of the terminal device, and also sends the TA adjustment parameter to the terminal device using the TAC field. Therefore, the terminal can adjust the TA based on the TA adjustment parameter. In addition, in the communication system, for example, 5th generation Mobile Networks new radio access technology (5G NR), the adjustment range each time the access network device adjusts the TA of the terminal device, and the overall range , which can be adjusted over a certain period of time, is limited.

[0005] However, in the current method of determining TA, only the mobility of the tag is taken into account. When the access network device is a satellite base station, since the satellite base station itself also has mobility, the existing TA determination method for a terminal cannot be directly applied to the satellite base station. Therefore, how to enable the application of the TA determination method for a terminal to a satellite base station is a technical problem that needs to be urgently solved in this field.

SUMMARY OF THE INVENTION

[0006] This application provides a TA determination method and equipment for a terminal device and a system for solving the problem that a TA determination method for a terminal device in conventional technology cannot be applied to a satellite base station.

[0007] According to a first aspect of this application, a method for determining a TA for a terminal is provided, including:

receiving a TA adjustment parameter from the access network device, where the TA adjustment parameter is used to indicate the TA adjustment of the terminal device;

determining a TA scaling factor of the tag, a subcarrier spacing parameter of the tag, and a first TA used when the tag communicates with the access network device prior to receiving the TA adjustment parameter, where the TA scaling factor is used to perform TA adjustment scaling processing of the terminal; And

determining a second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0008] Finally, in the method for determining a TA for a terminal presented in this application, after receiving a TA adjustment parameter sent by an access network device and determining that the TA of the terminal must be adjusted, the terminal determines the TA scaling factor, the diversity parameter subcarriers and the first TA to jointly adjust the first TA to obtain the second TA. In this embodiment, the TA adjustment parameter k is added when the terminal detects the second TA so that the adjustable range is larger when the terminal adjusts the TA. Therefore, TA may be applied to, for example, a satellite communication system to adjust the TA when the device moves, caused by both the terminal device and the satellite base station. In addition, the TA determination method for a terminal in this embodiment may be further applied to an existing terrestrial communication system, and the terminal may adjust the TA only in consideration of the mobility of the terminal. Therefore, the terminal TA determination method provided in this embodiment can be further applied to both a terrestrial fixed base station and a satellite base station, and is portable.

[0009] In an embodiment of the first aspect of this application, determining the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA includes: calculating TA ₂ using the formula TA ₂ = TA ₁ +k∙(T _A -31)∙16∙64/2 ^μ .

[0010] TA ₁ is the first TA, T _A is the TA adjustment parameter, k is the TA scaling factor, 2 ^μ is the subcarrier spacing parameter, ∆f=2 ^μ ∙15[kHz], and Δf is the terminal subcarrier spacing.

[0011] Finally, in the TA determination method for a terminal provided in this embodiment, the second TA is calculated using a formula, and extension is performed based on the existing TA determination method, so that the TA determination method in this embodiment is portable and compatible. with the existing communication system.

[0012] In an embodiment of the first aspect of this application, determining the TA scaling factor includes: determining the TA scaling factor based on the maximum moving speed of the tag, the moving speed of the access network device, and the frequency at which the access network device instructs the tag to adjust the TA.

[0013] In an embodiment of the first aspect of this application, determining the TA scaling factor based on the maximum moving speed of the tag, the moving speed of the access network device, and the frequency with which the access network device instructs the tag to adjust the TA includes: calculating the TA scaling factor k using the formula 2(v ₁ +v ₂ )/f _TA /c=k∙32∙16∙64∙T _c /8).

[0014] v₁ - maximum terminal device speed, v₂ - movement speed access network devices, f_TA is the frequency with which the access network device tells the terminal to adjust TA, c is the speed of light, and T_c - base unit time.

[0015] In an embodiment of the first aspect of this application, the method further includes: determining whether the TA adjustment of the terminal processed by the TA scaling factor satisfies a predetermined condition; and if the TA adjustment of the terminal satisfies the predetermined condition, determining a second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0016] In an embodiment of the first aspect of this application, the method includes: determining a scaling factor TA based on the speed of movement of the access network device, the height of the access network device, and the time advance in height of the access network device.

[0017] In an embodiment of the first aspect of this application, determining the TA scaling factor based on the speed of movement of the access network device, the height of the access network device, and the time advance in height of the access network device includes:

determining, by searching for the first display ratio, a scaling factor TA corresponding to a moving speed of the access network device, a height at which the access network device is located, and a time advance in height of the access network device. The first mapping relationship includes a correspondence between at least one of an access network device moving speed, an access network device height, and an access network device height advance, and a TA scale factor.

[0018] In an embodiment of the first aspect of this application, determining the TA scaling factor based on the speed of movement of the access network device, the height of the access network device, and the time advance in height of the access network device includes:

determining, by searching for the second mapping ratio, the scaling factor TA corresponding to the subcarrier spacing of the terminal device, the moving speed of the access network device, the height at which the access network device is located, and the height advance of the access network device. The second mapping relationship includes a correspondence between at least one of the tag subcarrier spacing, the access network device speed, the access network device height and the access network device height advance, and the TA scaling factor.

[0019] Finally, in the TA determination method for a terminal provided in this embodiment, the terminal can obtain, using a smaller calculation amount, a TA to be adjusted by searching for a mapping ratio. This improves the speed and efficiency of TA determination by the terminal.

[0020] In an embodiment of the first aspect of this application, determining a TA scaling factor includes: determining a TA scaling factor based on a random access preamble format used by a terminal during random access to an access network device.

[0021] In an embodiment of the first aspect of this application, determining the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA includes: determining the second TA based on the TA offset parameter, the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter and the first TA. The TA offset parameter is used to perform offset processing when adjusting the TA of the terminal.

[0022] In an embodiment of the first aspect of this application, determining a TA scaling factor includes: determining a TA scaling factor based on access network device attribute information.

[0023] In an embodiment of the first aspect of this application, before receiving the adjustment parameter TA from the access network device, the method further includes:

receiving indication information sent by the access network device, where the indication information is used to indicate the total delay of the cell in which the terminal device is located; And

determining a total delay based on the indication information.

[0024] In an embodiment of the first aspect of this application, before receiving the adjustment parameter TA from the access network device, the method further includes:

when the terminal accesses the access network device for the first time, obtaining an initial TA parameter from the access network device; And

determining an initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter.

[0025] In an embodiment of the first aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0026] Finally, in the method for determining a TA for a tag provided in this embodiment, the tag can jointly determine the initial TA of the tag based on the total delay indicated by the access network device and the initial TA parameter. Since the tag can determine the initial TA based on the total delay indicated by the access network device, the TA determination method for the tag can be applied to the radar base station so that the radar base station compensates the TA of the tag depending on the radar height and cell angle.

[0027] In an embodiment of the first aspect of this application, if the terminal is in a static state, the drift rate TA of the terminal is determined, where the drift rate TA is used to indicate the adjustment of the TA that is in the cell in which the terminal is located and which is caused movement of the access network device; and the fourth TA is determined based on the TA drift rate, the third TA, the TA adjustment parameter, and the subcarrier spacing parameter, where the third TA is the TA used when the terminal communicates with the access network device before determining the fourth TA.

[0028] In an embodiment of the first aspect of this application, determining the fourth TA based on the TA drift rate, the third TA, the TA adjustment parameter, and the subcarrier spacing parameter includes: calculating the fourth TA using the formula TA ₄ =TA ₃ +∆N _TA +∆ N' _TA ∙∆t. ∆N _TA =(T _A -31)∙16∙64/2 ^μ , where TA is the TA adjustment parameter sent by the access network device, ∆N' _TA is the TA setting, Δt=t1-t0, t0 is the time in which the terminal device receives the adjustment parameter TA, and t1 is the time at which the terminal device is to send uplink communication data to the access network device.

[0029] In an embodiment of the first aspect of this application, determining the drift rate TA of the terminal includes: determining the drift rate TA of the terminal according to the third mapping relation. The third mapping relationship includes a correspondence between the Doppler frequency shift of at least one access network device and the drift rate TA of the terminal device.

[0030] Finally, in the TA determination method for a terminal provided in this embodiment, the terminal may pre-compensate the TA adjustment based on a parameter such as Doppler to avoid frequent TA adjustment indications from the satellite base station and reduce overhead. resource spending. In addition, since the communication delay between the satellite base station and the terminal is relatively large, performing pre-compensation using the method of this embodiment can reduce the TA error introduced by the delay when the satellite base station indicates to adjust TA.

[0031] According to a second aspect of this application, a method for determining a TA for a terminal is provided, including:

determining a TA adjustment parameter of the terminal, where the TA adjustment parameter is used to indicate a TA adjustment of the terminal; And

sending the TA adjustment parameter to the terminal device such that the terminal device determines the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The TA scaling factor is used to perform scaling processing when adjusting the TA of the tag, and the first TA is the TA used when the tag communicates with the access network device before receiving the TA adjustment parameter.

[0032] In an embodiment of the second aspect of this application, the method further includes: sending indication information to the terminal device. The indication information is used to indicate the total delay of the cell in which the terminal resides.

[0033] In an embodiment of the second aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0034] In an embodiment of the second aspect of this application, sending indication information to a terminal device includes: broadcasting a total delay in a cell in which the terminal device is located; or broadcasting the height time advance in the coverage area of the access network device and broadcasting the angle time advance in the cell in which the terminal is located.

[0035] According to a third aspect of this application, a TA determination apparatus for a terminal device is provided, capable of executing the TA determination method for a terminal device in the first aspect of this application. The hardware includes:

a transceiver module, configured to receive a TA adjustment parameter from the access network device, where the TA adjustment parameter is used to indicate the TA adjustment of the terminal device;

a parameter determination module, configured to determine the TA scaling factor of the terminal device, the subcarrier spacing parameter of the terminal device, and the first TA used when the terminal device communicates with the access network device before receiving the TA adjustment parameter, where the TA scaling factor is used to perform scaling processing when adjusting the TA of the terminal; And

a TA determination module, configured to determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0036] In an embodiment of the third aspect of this application, the TA determination module is specifically configured to calculate TA₂ With using the TA formula₂=TA₁+k∙(T_A-31)∙16∙64/2^μ.

[0037]TA₁- This first TA, T_A - parameter adjustment TA, k - scaling factor TA, 2_μ - spacing parameter subcarriers, ∆f=2^μ∙15[kHz] and Δf - subcarrier spacing of the terminal device.

[0038] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine the TA scaling factor based on the maximum movement speed of the tag, the movement speed of the access network device, and the frequency with which the access network device instructs the tag to adjust the TA.

[0039] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to calculate the TA scaling factor k using the formula 2(v ₁ +v ₂ )/f _TA /c=k∙32∙16∙64∙T _c /8).

[0040]v₁ - maximum speed of the terminal device, v₂ - speed of movement of the access network device, f_TA is the frequency with which the access network device tells the terminal to adjust TA, c is the speed of light, and T_c - base unit time.

[0041] In an embodiment of the third aspect of this application, the parameter determination module is further configured to: determine whether the TA adjustment of the terminal processed by the TA scaling factor satisfies a predetermined condition; and if the TA adjustment of the terminal satisfies the predetermined condition, determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0042] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine the scaling factor TA based on the speed of movement of the access network device, the height of the access network device, and the time advance in height of the access network device.

[0043] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine, by searching for the first display ratio, the scaling factor TA corresponding to the speed of the access network device, the height at which the access network device is located, and the time advance in access network device height. The first mapping relationship includes a correspondence between at least one of an access network device moving speed, an access network device height, and an access network device height advance, and a TA scale factor.

[0044] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine, by searching for the second mapping ratio, the scaling factor TA corresponding to the subcarrier spacing of the terminal device, the speed of movement of the access network device, the height at which the access network device is located , and time advance in height of the access network device. The second mapping relationship includes a correspondence between at least one of the tag subcarrier spacing, the access network device speed, the access network device height and the access network device height advance, and the TA scaling factor.

[0045] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine the TA scaling factor based on the format of the random access preamble used by the terminal in the process of random access to the access network device.

[0046] In an embodiment of the third aspect of this application, the TA determination module is further configured to determine the second TA based on the TA offset parameter, the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The TA offset parameter is used to perform offset processing when adjusting the TA of the terminal.

[0047] In an embodiment of the third aspect of this application, the TA determination module is specifically configured to determine the TA scaling factor based on the attribute information of the access network device.

[0048] In an embodiment of the third aspect of this application, the transceiver module is further configured to receive indication information sent by the access network device. The indication information is used to indicate the total delay of the cell in which the terminal resides.

[0049] In an embodiment of the third aspect of this application, the parameter determination module is specifically configured to determine the total delay based on the indication information.

[0050] In an embodiment of the third aspect of this application, the transceiver module is further configured to: when the terminal device accesses the access network device for the first time, to receive the initial TA parameter from the access network device.

[0051] The TA determination module is further configured to determine the initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter.

[0052] In an embodiment of the third aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0053] In an embodiment of the third aspect of this application, the parameter determination module is further configured to: if the terminal is in a static state, determine the drift rate TA of the terminal. The TA drift rate is used to indicate the TA adjustment that occurs in the cell in which the terminal is located and is caused by movement of the access network device.

[0054] The TA determination module is further configured to determine a fourth TA based on a drift rate of the TA, a third TA, a TA adjustment parameter, and a subcarrier spacing parameter. The third TA is the TA used when the terminal communicates with the access network device before determining the fourth TA.

[0055] In an embodiment of the third aspect of this application, the TA determination module is further configured to calculate a fourth TA using the formula TA ₄ =TA ₃ +∆N _TA +∆N' _TA ∙∆t. ∆N _TA =(T _A -31)∙16∙64/2 ^μ , T _A is the TA adjustment parameter sent by the access network device, ∆N' _TA is the TA adjustment, Δt=t1-t0, t0 is the time in which the terminal device receives the adjustment parameter TA, and t1 is the time at which the terminal device is to send uplink communication data to the access network device.

[0056] In an embodiment of the third aspect of this application, the parameter determination module is further configured to determine the drift rate TA of the terminal according to the third mapping relationship. The third mapping relationship includes a correspondence between the Doppler frequency shift of at least one access network device and the drift rate TA of the terminal device.

[0057] According to a fourth aspect of this application, a TA determination apparatus for a terminal device is provided, configured to execute the TA determination method for a terminal device in the second aspect of this application. The hardware includes:

a determining module, configured to determine a TA adjustment parameter of the terminal device, where the TA adjustment parameter is used to indicate the TA adjustment of the terminal device; And

a transceiver module configured to send the TA adjustment parameter to the terminal device, such that the terminal device determines the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The TA scaling factor is used to perform scaling processing when adjusting the TA of the tag, and the first TA is the TA used when the tag communicates with the access network device before receiving the TA adjustment parameter.

[0058] In an embodiment of the fourth aspect of this application, the transceiver module is further configured to send indication information to the terminal device. The indication information is used to indicate the total delay of the cell in which the terminal resides.

[0059] In an embodiment of the fourth aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0060] In an embodiment of the fourth aspect of this application, the transceiver module is specifically configured to: broadcast the total delay in the cell in which the terminal is located; or broadcasting the height time advance in the coverage area of the access network device and broadcasting the angle time advance in the cell in which the terminal device is located.

[0061] According to a fifth aspect of this application, communication equipment is provided. The communication equipment may be a terminal device, and the communication equipment includes a communication interface, a processor, and a memory. The communication interface is configured to receive the adjustment parameter TA from the access network device and send the adjustment parameter TA to the processor. The TA adjustment parameter is used to indicate the TA adjustment of the terminal. The memory stores instructions, and when the processor calls and executes the instructions, after receiving the TA adjustment parameter, the processor has the ability to determine the TA scaling factor of the terminal device, the subcarrier spacing parameter of the terminal device, and the first TA used when the terminal device communicates with the access network device before receiving the TA adjustment parameter. The TA scaling factor is used to perform scaling processing when adjusting the TA of the terminal. The processor is further configured to determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0062] In an embodiment of the fifth aspect of this application, the processor is specifically configured to calculate TA ₂ using the formula TA ₂ = TA ₁ +k∙(T _A -31)∙16∙64/2 ^μ .

[0063]TA₁ - This first TA, T_A - adjustment parameter TA, k - scaling factor TA, 2^μ - subcarrier spacing parameter, ∆f=2^μ∙15[kHz] and Δf - subcarrier spacing of the terminal device.

[0064] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine the TA scaling factor based on the maximum tag movement speed, the access network device's movement speed, and the frequency at which the access network device instructs the tag to adjust the TA.

[0065] In an embodiment of the fifth aspect of this application, the processor is specifically configured to calculate the TA scaling factor k using the formula 2(v ₁ +v ₂ )/f _TA /c=k∙32∙16∙64∙T _c /8 .

[0066]v₁ - maximum speed of the terminal device, v₂ - movement speed access network devices, f_TA is the frequency with which the access network device tells the terminal to adjust TA, c is the speed of light, and T_c - base unit time.

[0067] In an embodiment of the fifth aspect of this application, the processor is further configured to: determine whether the TA adjustment of the terminal processed by the TA scaling factor satisfies a predetermined condition; and if the TA adjustment of the terminal satisfies the predetermined condition, determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[0068] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine the scaling factor TA based on the speed of movement of the access network device, the height of the access network device, and the time advance in height of the access network device.

[0069] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine, by searching for the first display ratio, a scaling factor TA corresponding to the speed of movement of the access network device, the height at which the access network device is located, and the time advance in height of the device access networks. The first mapping relationship includes a correspondence between at least one of an access network device moving speed, an access network device height, and an access network device height advance, and a TA scale factor.

[0070] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine, by searching for the second mapping ratio, the scaling factor TA corresponding to the subcarrier spacing of the terminal device, the speed of movement of the access network device, the height at which the access network device is located, and time advance in height of the access network device. The second mapping relationship includes a correspondence between at least one of the tag subcarrier spacing, the access network device speed, the access network device height and the access network device height advance, and the TA scaling factor.

[0071] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine the TA scaling factor based on the format of the random access preamble used by the terminal in the process of random access to the access network device.

[0072] In an embodiment of the fifth aspect of this application, the processor is further configured to determine the second TA based on the TA offset parameter, the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The TA offset parameter is used to perform offset processing when adjusting the TA of the terminal.

[0073] In an embodiment of the fifth aspect of this application, the processor is specifically configured to determine a TA scaling factor based on access network device attribute information.

[0074] In an embodiment of the fifth aspect of this application, the communication interface is further configured to receive indication information sent by the access network device and send the indication information to the processor. The indication information is used to indicate the total delay of the cell in which the terminal resides.

[0075] In an embodiment of the fifth aspect of this application, the processor is further configured to determine a total delay based on the indication information when receiving the indication information.

[0076] In an embodiment of the fifth aspect of this application, the communication interface is further configured to: when the terminal device accesses the access network device for the first time, receive the initial TA from the access network device and send the initial TA to the processor.

[0077] The processor is further configured to determine the initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter upon receiving the initial TA parameter.

[0078] In an embodiment of the fifth aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0079] In an embodiment of the fifth aspect of this application, the processor is further configured to: if the tag is in a static state, determine the drift rate TA of the tag. The TA drift rate is used to indicate the TA adjustment that occurs in the cell where the terminal is located and is caused by movement of the access network device.

[0080] The processor is further configured to determine a fourth TA based on the TA drift rate, a third TA, a TA adjustment parameter, and a subcarrier spacing parameter. The third TA is the TA used when the terminal communicates with the access network device before determining the fourth TA.

[0081] In an embodiment of the fifth aspect of this application, the processor is further configured to calculate a fourth TA using the formula TA ₄ =TA ₃ +∆N _TA +∆N' _TA ∙∆t. ∆N _TA =(T _A -31)∙16∙64/2 ^μ , T _A is the TA adjustment parameter sent by the access network device, ∆N' _TA is the TA adjustment, Δt=t1-t0, t0 is the time in which the terminal device receives the adjustment parameter TA, and t1 is the time at which the terminal device is to send uplink communication data to the access network device.

[0082] In an embodiment of the fifth aspect of this application, the processor is further configured to determine the drift rate TA of the terminal in accordance with the third mapping relationship. The third mapping relationship includes a correspondence between the Doppler frequency shift of at least one access network device and the drift rate TA of the terminal device.

[0083] According to the sixth aspect of this application, communication equipment is provided. The communication equipment may be an access network device, and more specifically, the communication equipment may be a radar base station. The communications equipment includes a communications interface, a processor, and a memory. The memory stores instructions, and when the processor calls and executes the instructions, the processor has the ability to determine the TA adjustment parameter of the terminal device and send the TA adjustment parameter to the communication interface. The TA adjustment parameter is used to indicate the TA adjustment of the terminal. Upon receiving the TA adjustment parameter, the communication interface sends the TA adjustment parameter to the terminal device, so that the terminal device determines the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The TA scaling factor is used to perform scaling processing when adjusting the TA of the tag, and the first TA is the TA used when the tag communicates with the access network device before receiving the TA adjustment parameter.

[0084] In an embodiment of the sixth aspect of this application, the communication interface is further configured to send indication information to the terminal device, where the indication information is used to indicate the total delay of the cell in which the terminal device is located.

[0085] In an embodiment of the sixth aspect of this application, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[0086] In an embodiment of the sixth aspect of this application, the communication interface is specifically configured to: broadcast the total delay in the cell in which the terminal is located; or broadcasting the height time advance in the coverage area of the access network device and broadcasting the angle time advance in the cell in which the terminal device is located.

[0087] According to a seventh aspect, an embodiment of this application further provides a computer-readable storage medium including instructions. When the instructions are executed on a computer, the computer is able to execute the method according to the first aspect of this application.

[0088] According to an eighth aspect, an embodiment of this application further provides a computer-readable storage medium including instructions. When the instructions are executed on the computer, the computer is enabled to execute the method according to the second aspect of this application.

[0089] According to a ninth aspect, an embodiment of this application provides a communication system. The system includes apparatus according to a third aspect and apparatus according to a fourth aspect; or the system includes the communication equipment according to the fifth aspect and the communication equipment according to the sixth aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] FIG. 1 is a schematic diagram of a communication system according to conventional technology;

[0091] FIG. 2 is a schematic diagram of a communication system according to this application;

[0092] FIG. 3 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application;

[0093] FIG. 4 is a schematic diagram of the total delay of a cell in which a terminal resides, in accordance with this application;

[0094] FIG. 5 is a schematic diagram of the location of a satellite base station according to this application;

[0095] FIG. 6 is a schematic diagram of the correspondence between the location of the satellite base station and the TA of the terminal according to this application;

[0096] FIG. 7 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application;

[0097] FIG. 8 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application;

[0098] FIG. 9 is a schematic diagram of the Doppler frequency shift of an access network device in accordance with this application;

[0099] FIG. 10 is a schematic diagram of the drift rate TA of a terminal in accordance with this application;

[00100] FIG. 11 is a schematic diagram of the determination of the fourth TA by the terminal in accordance with this application;

[00101] FIG. 12 is a schematic diagram of 1 cell division based on drift rate TA according to this application;

[00102] FIG. 13 is a schematic diagram 2 of cell division based on drift rate TA according to this application;

[00103] FIG. 14 is a schematic diagram of a structure in an embodiment of a terminal device according to this application;

[00104] FIG. 15 is a schematic diagram of a structure in an embodiment of an access network device according to this application; And

[00105] FIG. 16 is a schematic diagram of a structure in an embodiment of a communication device according to this application.

Description of Embodiments

[00106] FIG. 1 is a schematic diagram of a communication system according to conventional technology. The communication scenario shown in Fig. 1 includes terminal A, terminal B, and an access network device. After establishing a communication connection with the access network device, the terminal device can further communicate with the core network using the access network device. For example, in the example shown in FIG. 1 shows that when the access network device is base station E, within the coverage area of base station E, both end device A and end device B can access base station E and communicate with base station E using the set wireless connection. The communication includes: terminal A sends uplink communication data to a base station, and the base station sends uplink communication data to a terminal.

[00107] In the conventional technology, when the distance between a terminal device and a base station is relatively large, there is a relatively large transmission delay when the terminal device sends uplink communication data to the base station, and various transmission delays exist in the uplink communication data sent through various terminals to a base station in the coverage area of the base station. For example, in the example shown in FIG. 1, a transmission delay TA 1 exists in the uplink communication data sent by the terminal device A to the base station E, and a transmission delay TA 2 exists in the uplink communication data sent by the terminal device B to the base station E. Since the distance between the terminal device B and the base station E is greater than the distance between terminal A and the base station, the transmission delay TA 2 is greater than the transmission delay TA 1. Therefore, in order to ensure the time synchronization of the uplink communication data of the terminal device received by the base station side, the base station sets a timing advance (TA) for each terminal that is being accessed, so that the terminal can obtain, using TA, a negative offset between the first time the terminal receives downlink communication data sent base station, and a second time when the terminal device sends uplink communication data to the base station. Thus, the base station controls, by controlling the time at which the accessed terminal sends the uplink communication data, the time at which the base station receives the uplink communication data of the terminal.

[00108] For example, in some specific implementations, when a tag randomly accesses a base station, the base station determines the TA of the tag based on the random access preamble sent by the tag, and sends an initial TA parameter to the tag using the TAC field, so that the terminal may determine the initial TA based on the initial TA parameter. However, due to the mobility of the tag, after the tag determines the initial TA, the base station additionally needs to constantly tell the tag to adjust the TA of the tag. After receiving the uplink communication data sent by the terminal device, the base station determines, by measuring the corresponding parameter of the uplink communication data, a TA adjustment to adjust the TA of the terminal device, and also sends the TA adjustment parameter to the terminal device with the TAC field, so that the terminal may adjust the TA based on the TA adjustment parameter.

[00109] FIG. 2 is a schematic diagram of a communication system to which this application applies. The application scenario shown in Fig. 2, this is a satellite base station communication scenario. The communication system includes a satellite base station and at least one terminal device. Alternatively, in some specific implementations, the communication system shown in FIG. 2 further includes a terrestrial base station, which is not shown. The terrestrial base station and the satellite base station jointly provide services to the terminal. The satellite base station has a wider coverage and is not susceptible to damage from natural disasters or external forces. Therefore, the satellite base station can provide communication services for some areas, such as ocean or forest, which cannot be covered by a terrestrial communication network, and has features such as wide coverage, reliability, multiple connections, and high throughput.

[00110] In embodiments of this application, a terminal may also be referred to as a terminal. The terminal may be a user equipment (user equipment, UE), a mobile station (mobile station, MS), a mobile terminal (mobile terminal, MT), or the like. The end device can also be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiver function, a virtual reality (VR) end device, an augmented reality (AR) end device, a wireless end device in industrial control, wireless terminal in self driving, wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation security safety), a wireless terminal in a smart city, a wireless terminal in a smart home, and the like.

[00111] Since the distance between the terminal device and the satellite base station is relatively large, the satellite base station also needs to instruct each terminal device that accesses the satellite base station to determine the TA of the terminal device in order to control the time synchronization of the uplink communication data of the terminal device, received by the base station. However, in the conventional technology shown in FIG. 1, the location of the base station E in the terrestrial communication network is fixed, and only the mobility of the terminal is taken into account when the terminal detects TA. In the communication system, for example, 5th generation Mobile Networks new radio access technology (5G NR), the adjustment range each time the base station in the terrestrial communication network adjusts the TA of the terminal device and the overall range, which can be adjusted for a certain period of time are limited.

[00112] In the communication scenario shown in FIG. 2, the existing satellite base station is usually in a state of continuous movement, for example, at the first moment, terminal C is at location C in the figure, and the satellite base station is at location C' in the figure. In this case, transmission delay TA 3 occurs in the uplink communication data sent by the terminal to the satellite base station. Therefore, the terminal needs to send the uplink communication data using the TA 3 time advance in advance. However, at the second moment, since the terminal moves from location C to location D and the satellite base station moves from location C' to D', the transmission delay TA 4 occurs in uplink communication data sent by the terminal to the satellite base station. Therefore, the terminal needs to send uplink communication data using TA 4 time advance in advance. Obviously, since the distance between location D and location D' is greater than the distance between location C and location C', TA 4 > TA 3.

[00113] For example, in a 5G NR communication system, when a tag determines a TA, both the frequency for determining the TA and the maximum adjustment of the TA are simultaneously limited, and the mobility of the base station is not taken into account. However, in the satellite communication system shown in FIG. 2, since the satellite base station itself also has mobility, and the movement speed of the satellite base station is much larger than the movement speed of the terminal device, the existing method for determining the TA for the terminal device cannot be directly applied to the satellite base station. Therefore, how to enable the application of the TA determination method for a terminal to a satellite base station is a technical problem that needs to be urgently solved in this field.

[00114] The following describes a method for determining a TA for a terminal provided by this application with reference to the accompanying drawings.

[00115] FIG. 3 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application. As shown in FIG. 3, a method for determining a TA for a terminal according to an embodiment of this application includes the following steps.

[00116] S101: The access network device sends indication information to the terminal device.

[00117] Specifically, the access network device in this embodiment includes a satellite base station. In this case, in order to compensate for the TA value in determining the initial TA in the process in which the terminal device accesses the satellite base station, the access network device must send indication information to the terminal device, which may indicate the total delay in the cell in which the terminal is located. device.

[00118] The total delay in this embodiment includes the height time advance TA(h) of the access network device and the angular time advance TA(θ) of the cell in which the terminal device is located.

[00119] For example, FIG. 4 is a schematic diagram of the total delay of a cell in which a terminal resides in accordance with this application. In the coverage area S of the satellite base station O in FIG. 4, the total delays of different cells are different.

[00120] Cell S1 directly below satellite base station O is used as an example. When a terminal located at point a directly below satellite base station O in a cell sends uplink communication data to satellite base station O, there is a time delay between a and O due to the height h of satellite base station O. In this embodiment, the time delay is referred to as high time advance TA(h). In other words, when all terminals in the coverage area S of the satellite base station O send uplink data to the satellite base station O, at least a total delay exists and TA(h) needs to be compensated.

[00121] In addition to the cell S1 located directly below the satellite base station O, when sending uplink data to the satellite base station, the terminal in another cell in the coverage area S additionally needs to take into account the angular time advance of each cell. For example, the base station S2 shown in FIG. 4 is used as an example. Point c in the cell is the location closest to point a directly below the satellite base station O. When the terminal is at location c, there is a time advance TA(h) in height caused by the height h of the satellite base station, and there is also an angular time advance TA(θ) caused by the angle θ between point c and satellite base station O. In other words, when the terminal at point c sends uplink communication data to satellite base station O, the total delay to be compensated between c and O includes into the time advance TA(h) in height between O and b and the angular time advance TA(θ) between b and c. Therefore, when all terminals in cell S2 send uplink communication data to the satellite base station, a total delay exists and the total delay compensation needs to be performed, that is, TA(h) + TA(θ).

[00122] However, the distances between terminals in cell S2 and point a are not exactly the same, and different distances cause different TA compensation values required for different terminals in the same cell. For example, point e is the location in cell S2 furthest from point a. In addition to performing TA(h) + TA(θ) compensation at point e, the terminal additionally needs to perform ΔTA compensation at the terminal. Finally, for a terminal in cell S2, the TA compensation required by the radar base station includes TA(h) + TA(θ) + ΔTA. For example, FIG. 5 is a schematic location diagram of a satellite base station according to this embodiment, where R is the radius of the Earth and h is the orbital height at which the satellite base station moves around the Earth. For changing the relationship between the location of the satellite base station and TA when the satellite base station moves around the Earth and represents an angle α with the initial location, see FIG. 6. FIG. 6 is the correspondence between the location of the satellite base station and the TA of the terminal in this application. As shown in FIG. 6, for a cell in the coverage area of a satellite base station at 150 s in the figure, at an altitude of about 1300 km and an angle α of about 0.33 rad, the TA of the terminal in the cell includes TA(h) + TA(θ ) + ΔTA. Optionally, when a terminal accesses a satellite base station, the satellite base station sends ΔTA to the terminal to compensate for the TA of the terminal.

[00123] Therefore, in step S101, in order for the terminal device to determine the total delay to be compensated for when communicating with the satellite base station, the satellite base station needs to send indication information to the terminal device in the coverage area of the satellite base station, because the terminal device may determine, based on the indication information, the total delay of the detected cell.

[00124] Optionally, in the first possible implementation of S101, the satellite base station may broadcast in each cell the total delay corresponding to the cell. For example, in the scenario shown in FIG. 4, the satellite base station O broadcasts on the cell S1 the total delay TA(h) corresponding to the cell S1, and broadcasts on the cell S2 the total delay TA(h) + TA(θ) corresponding to the cell S2.

[00125] Alternatively, in the second possible implementation of S101, since all terminals in the coverage area S of the satellite base station O have a delay TA(h), the satellite base station O may broadcast TA(h) in the coverage area S of the satellite base station O and broadcast in each cell TA(θ) corresponding to the cell.

[00126] Alternatively, in a third possible implementation of S101, the satellite base station may indicate the total latency of the detected cell to the tag in an implicit indication manner. For example, if there is a correspondence between the cell ID or beam ID of the satellite base station radar and the total delay in the cell, the indication information may be the cell ID or beam ID sent by the satellite base station to the terminal device, so that the terminal device determines the corresponding total delay. based on the cell ID or beam ID sent by the satellite base station. The match may be sent by the satellite base station to the terminal, the match may be obtained through negotiation between the satellite base station and the terminal, or the match may be stored in the terminal.

[00127] S102: The access network device sends the initial TA parameter to the terminal device, so that the terminal device determines the initial TA.

[00128] In particular, when accessing the access network device for the first time, the terminal device may receive the initial TA parameter from the access network device. For example, in a process in which a terminal device randomly accesses a radar base station, the radar base station sends an initial TA parameter to the terminal device using the TAC (timing advance command) field in the random access response (RAR), where the initial the TA parameter includes 12 bits, and the initial TA parameter ranges from 0 to 3846.

[00129] S103: The terminal jointly determines the initial TA based on the indication information and the initial TA parameter.

[00130] In particular, the terminal can obtain the initial TA using the formula N _TA0 =TA(h)+TA(θ)+T _A0 ∙16∙64/2 ^μ where TA(h) + TA(θ) is the total delay _, T _A0 is the initial parameter TA, and 2 ^{μ is} the subcarrier spacing parameter. For the subcarrier spacing parameter ∆f=2 ^μ ∙15[kHz], where Δf is the terminal subcarrier spacing and the unit of time N _TA0 is T _c =0.509 ns, which is the base unit of time defined in TS 38.211.

[00131] S104: The terminal communicates with the access network device using the initial TA.

[00132] A tag may communicate with an access network device using an initial TA after determining the tag's initial TA through the above steps. For example, when the access network device is a radar base station, communication means that the terminal must send uplink transmission data to the radar base station in a time period TA in advance.

[00133] Finally, in the method for determining a TA for a tag provided in this embodiment, the tag can jointly determine the initial TA of the tag based on the total delay indicated by the access network device and the initial TA parameter. Since the tag can determine the initial TA based on the total delay indicated by the access network device, the TA determination method for the tag can be applied to the radar base station so that the radar base station compensates the TA of the tag depending on the radar height and cell angle.

[00134] Subsequently, after the tag performs random access and determines the initial TA, since both the tag and the access network device in this embodiment have mobility, the tag needs to continuously adjust the TA thereafter to meet the real-time TA requirement . Fig. 7 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application. 7 shows a post-TA adjustment process after a terminal has randomly accessed an access network device and obtained an initial TA. This embodiment can be applied to the communication scenario shown in FIG. 2. The access network device is a radar base station. The method includes the following steps.

[00135] S201: The access network device sends a TA adjustment parameter to the terminal device. The TA adjustment parameter is used to indicate the TA adjustment of the terminal.

[00136] In particular, in this embodiment, in the process of communicating with the terminal device, the access network device can measure the received uplink communication data sent by the terminal device, and when determining that the TA of the terminal device needs to be adjusted, send the TA adjustment parameter to tag, so that the tag adjusts the TA of the tag based on the TA adjustment parameter. Optionally, at this stage, the TAC sent by the access network device to the terminal device carries a TA adjustment parameter, where the TA adjustment parameter includes 6 bits and the TA adjustment parameter ranges from 0 to 63.

[00137] S202: The terminal determines the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[00138] Next, after receiving the TA adjustment parameter sent by the access network device in step S201, the terminal decides to adjust the TA. In this case, the terminal needs to determine the TA scaling factor, the subcarrier spacing parameter, and the first TA needed to calculate the TA in step S202. The TA scaling factor is used to perform scaling processing when adjusting the TA of the terminal. The first TA is the TA used when the terminal communicates with the access network device prior to receiving the TA adjustment parameter. The first TA may be the initial TA, or the first TA may be the TA obtained after adjusting the initial TA.

[00139] S203: The terminal jointly determines the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[00140] In particular, at this stage, the terminal device calculates TA₂using the TA formula₂=TA₁+k∙(T_A-31)∙16∙64/2^μ. T_A - This adjustment parameter TA adopted at S201, TA₁ - This the first TA determined in S202, k is the TA scaling factor determined in S202, and 2^μ - parameter subcarrier spacing defined in S202. For the subcarrier spacing parameter ∆f=2^μ∙15[kHz], where Δf is the subcarrier spacing of the terminal.

[00141] S204: The terminal communicates with the access network device using the second TA.

[00142] Finally, the terminal communicates with the access network device using the second TA defined in the previous steps. Communication means that the terminal needs to send uplink transmission data to the access network device for the second time period TA in advance. It can be understood that in the embodiment shown in FIG. 7, before receiving the adjustment parameter TA sent by the access network device in step S201, the terminal device sends uplink transmission data to the access network device for the first time period TA in advance. After determining the adjustment parameter TA in step S203, the terminal device sends uplink transmission data to the access network device for the second time period TA in advance.

[00143] Finally, in the method for determining a TA for a tag provided in this application, after receiving a TA adjustment parameter sent by an access network device and determining that the TA of the tag needs to be adjusted, the tag determines the TA scaling factor, the diversity parameter subcarriers and the first TA to jointly adjust the first TA to obtain the second TA. In this embodiment, when the terminal determines the second TA in step S203, the adjustment that can be adjusted based on the first TA is k∙(T _A -31)∙16∙64/2 ^μ . Compared with the (T _A -31)∙16∙64/2 ^μ adjustment specified in the existing 5G NR system, the TA adjustment parameter k is added so that the adjustment range is larger when the terminal device adjusts TA. Therefore, TA can be applied to the satellite communication system shown in FIG. 2 to adjust the TA in the case of mobility caused by both the terminal and the satellite base station. In addition, the TA determination method for a terminal in this embodiment can be further applied to an existing terrestrial communication system shown in FIG. 1 and the terminal can only adjust the TA based on the mobility of the terminal. Therefore, the terminal TA determination method provided in this embodiment can be further applied to both a terrestrial fixed base station and a satellite base station, and is portable.

[00144] Optionally, based on the embodiment shown in FIG. 7, in step S202, in a possible specific implementation of determining the TA scaling factor k, the tag specifically determines the TA scaling factor k based on the maximum moving speed of the tag, the moving speed of the access network device and the frequency at which the access network device instructs the terminal to adjust the TA. For example, the terminal may calculate the TA scaling factor k from the formula 2(v₁+v₂)/f_TA/c=k∙32∙16∙64∙T_c/8, where v_{1 -}maximum speed of the terminal device, v₂ - speed movement of the access network device, f_TA - frequency, s which the access network device instructs the terminal device to adjust TA, c is the speed of light, the typical value of the speed of light is 299792458 m/s, and T_c - basic unit of time.

[00145] Optional, f_TAmay be determined by the terminal device based on the satellite type of the access network device being accessed, without the device directly specifying the access network. The types of satellites may be low orbit, medium orbit, high orbit, and the like, which are classified by the satellite base station based on flight altitude. Satellites operating in different orbits have different operating parameters and must match different frequencies in order to adjust the TA. Therefore, after accessing the satellite base station, the terminal can determine, based on the type of satellite base station, f_T.A.,corresponding to the current satellite base station. Alternatively, after determining the operating parameter of the satellite base station based on the type of satellite base station, the terminal may further determine based on the operating parameter f_T.A.,corresponding satellite base station. Optional, satellite type, operating parameter and correspondence between operating parameter and f_TA may be stored in the access network device and/or terminal device in the form of a table. Alternatively, the access network device and/or terminal device may directly store a table used to indicate the correspondence between satellite type and f_TA.

. Универсальная гравитационная постоянная G=6,67*10^-11 Н·м/кг, масса Земли M=5,965*10²⁴ кг, радиус Земли R=6371 км, рабочая высота радарной базовой станции h. Высота движения h радарной базовой станции может быть получена по формуле TA(h)=2h/c, где TA(h) - это временное опережение по высоте общей задержки, отправляемой радарной базовой станцией, принятой оконечным устройством. Опционально, на этапе S203 в этом варианте осуществления после доступа к устройству сети доступа оконечное устройство может определять разнесение поднесущих, используемое во время связи оконечного устройства, и частоту, с которой устройство сети доступа указывает оконечному устройству регулировать TA. Частота для регулировки TA - это частота, с которой устройство сети доступа отправляет параметр регулировки TA на оконечное устройство, показанное на фиг. 7.[00146] The value of the TA scaling factor k can be represented based on the maximum change in TA that must be adjusted by the terminal each time the TA is adjusted, and when the elevation angle of the terminal is maximum, when the terminal is communicating with the access network device, and the movement direction of the terminal device is opposite to the direction of movement of the access network device, TA, which should be controlled by the terminal device, is the maximum. Therefore, in the above formula, it is necessary to take into account the sum of the maximum speed of movement of the terminal device and the speed of movement of the access network device. In this case, the rate of change of TA is maximum. When the access network device is a radar base station, since the working height of the radar base station is known, the speed v ₂ of the radar base station can be calculated using the formula

. Universal gravitational constant G=6.67*10 ^-11 N m/kg, Earth mass M=5.965*10 ²⁴ kg, Earth radius R=6371 km, radar base station working height h. The movement height h of the radar base station can be obtained by the formula TA(h)=2h/c, where TA(h) is the time advance height of the total delay sent by the radar base station received by the terminal. Optionally, in step S203 in this embodiment, after accessing the access network device, the terminal may determine the subcarrier spacing used during communication of the terminal and the frequency at which the access network device instructs the terminal to adjust TA. The TA adjustment frequency is the frequency at which the access network device sends the TA adjustment parameter to the terminal device shown in FIG. 7.

[00147] In addition, based on the above embodiment, when a terminal operates at the maximum subcarrier spacing of the terminal, the TA range that can be indicated by the TA adjustment parameter sent by the access network device to the terminal is the minimum. However, the TA scaling factor k obtained by calculating using the above formula is based on the maximum subcarrier spacing of the terminal, and therefore a different subcarrier spacing of the terminal can be observed. However, when the subcarrier spacing is reduced, the TA scaling factor k is still used, and the TA adjustment accuracy is reduced to some extent. Therefore, in this embodiment, it can be further determined that the TA adjustment range cannot be met if the TA scaling factor k is not added to the TA adjustment parameter. For example, it is determined whether the TA adjustment obtained after the TA scaling factor processing conforms to a predetermined condition. Only when 2(v ₁ +v ₂ )/f _TA /c > k∙32∙16∙64∙T _c /8, the above formula can be used to adjust TA. When 2(v ₁ +v ₂ )/f _TA /c ≤ k∙32∙16∙64∙T _c /8, the formula TA ₂ = TA ₁ +k∙(T _A -31)∙16∙64/2 ^μ used to adjust TA. Thus, when the subcarrier spacing of the terminal is relatively small, the TA scaling factor is not added to the TA adjustment, but is directly adjusted by the TA based on the TA adjustment to improve the TA adjustment accuracy of the terminal when the subcarrier spacing is relatively small.

[00148] In another possible specific implementation of determining the TA scaling factor in step S202, the tag specifically determines the TA scaling factor using the speed of the access network device, the height at which the access network device is located, and the time advance in height of the access network device. For example, the terminal device may determine, by searching for the first mapping ratio, a TA scaling factor corresponding to the speed of the access network device, the height at which the access network device is located, and the height time advance of the access network device, where the first mapping ratio includes correspondence between at least one of the movement speed of the access network device, the height of the access network device and the time advance in height of the access network device and the scaling factor TA.

[00149] For example, the terminal may store the first mapping relationship in a table. Refer to Table 1 for the specific table configuration method. The various correspondences listed in Table 1 are merely examples for description, but are not limited to the correspondences mentioned. In Table 1, the frequency at which an access network device instructs a terminal to adjust TA f_TA=5, i.e. TA is adjusted every 200 ms, and the maximum speed of the terminal device is 1000 km/h. Therefore, it can be understood that if the correspondence between the speed of movement of another access network device, the height of the access network device, the time advance in height of the access network device, and the TA scaling factor is obtained due to a change in another parameter, for example, the frequency for adjusting the TA or the speed of movement of the terminal device, and if the match is only changed in numerical value, the match also falls within the protection scope of that application.

Table 1

Altitude at which the access network device is located (km) Access network device movement speed Time advance in height
TA(h) TA scaling factor k 300 7.72276235 2 5.120673 400 7.665521994 2.666667 5.084037 500 7.609535837 3.333333 5.048204 600 7.554758737 4 5.013144 700 7.501147793 4.666667 4.978831 800 7.448662207 5.333333 4.945238 900 7.397263151 6 4.912341 1000 7.346913647 6.666667 4.880115 1100 7.297578456 7.333333 4.848538 1200 7.249223971 8 4.817589 1300 7.201818127 8.666667 4.787248 1400 7.155330305 9.333333 4.757494 1500 7.109731253 10 4.728308 1600 7.064993008 10.66667 4.699674 1700 7.021088823 11.33333 4.671574 1800 6.977993101 12 4.643991 1900 6.935681329 12.66667 4.616909 2000 6.894130024 13.33333 4.590315 2100 6.853316677 14 4.564193 2200 6.813219699 14.66667 4.538529 2300 6.773818376 15.33333 4.51331 2400 6.735092822 16 4.488524 2500 6.697023939 16.66667 4.464159 2600 6.659593375 17.33333 4.440202 2700 6.62278349 18 4.4166425 2800 6.586577318 18.66667 4.393468 2900 6.550958533 19.33333 4.370671 3000 6.515911425 20 4.348239 3100 6.481420862 20.66667 4.326164 3200 6.447472268 21.33333 4.304439 3300 6.414051598 22 4.283045 3400 6.381145309 22.66667 4.261984 3500 6.34874034 23.33333 4.241243 3600 6.316824089 24 4.220815 3700 6.285384395 24.66667 4.200693 3800 6.254409515 25.33333 4.180867 3900 6.223888108 26 4.161332 4000 6.193809215 26.66667 4.142081 4100 6.164162246 27.33333 4.123105 4200 6.134936961 28 4.1044 4300 6.106123459 28.66667 4.085958 4400 6.077712159 29.33333 4.067774 4500 6.049693791 thirty 4.049841 4600 6.022059379 30.66667 4.032154 4700 5.994800234 31.33333 4.014707 4800 5.967907939 32 3.997495 4900 5.941374338 32.66667 3.980512 5000 5.915191528 33.33333 3.963754 5100 5.889351847 34 3.947216 5200 5.863847865 34.66667 3.930892 5300 5.838672375 35.33333 3.914779 5400 5.813818387 36 3.898871 5500 5.789279115 36.66667 3.883165 5600 5.765047973 37.33333 3.867656 5700 5.741118565 38 3.85234 5800 5.717484682 38.66667 3.837214 5900 5.69414029 39.33333 3.822272 6000 5.671079526 40 3.807512

[00150] Optionally, based on the embodiment shown in Table 1, in order to reduce the occupied memory space when the terminal device stores the table, in this embodiment, the access network device heights can be further classified into different levels, and each level corresponds to one maximum factor k TA scaling. In addition, the data in the table can be further processed by rounding up or to the nearest 0.5 to reduce storage space. For example, Table 1.1 and Table 1.2 show two possible ways to compress Table 1.

Table 1.1

Height at which the access network device is located
(km) Access network device movement speed Height advance
TA(h) TA scaling factor k 300-600 7.72-7.55 2.00-4.00 6 700-4700 7.50-5.99 4.67-31.33 5 4800-6000 5.97-5.67 32.00-40.00 4 ... ... ... ...

Table 1.2

Height at which the access network device is located
(km) Access network device movement speed Height advance
TA(h) TA scaling factor k 300-600 7.72-7.55 2.00-4.00 5.5 700-2300 7.55-6.77 4.67-15.33 5 2400-4700 6.74-5.99 16.00-31.33 4.5 4800-6000 5.97-5.67 32.00-40.00 4 ... ... ... ...

[00151] In the first mapping relationship shown in Table 1, the tag operates by default using the maximum subcarrier spacing of the tag. In order to improve the precision of the TA adjustment by the terminal, the TA adjustment parameters k corresponding to different subcarrier spacings of the terminal may be further added in accordance with the first mapping relationship. The terminal device may determine, by searching for the second mapping ratio, a TA scaling factor corresponding to the subcarrier spacing of the terminal device, the speed of movement of the access network device, the height at which the access network device is located, and the height advance of the access network device, where the second mapping ratio includes a correspondence between at least one of the terminal subcarrier spacing, the access network device speed, the access network device height and the access network device height advance, and the TA scaling factor.

[00152] For example, the terminal may store the second mapping relationship in a table. Refer to Table 2 for the specific table configuration method. The various correspondences listed in Table 2 are merely examples for description, but are not limited to the correspondences mentioned. In Table 2, the frequency at which an access network device instructs a terminal to adjust TA f_TA=5, i.e. TA is adjusted every 200 ms, and the maximum speed of the terminal device is 1000 km/h. Therefore, it can be understood that if the correspondence between the sub-carrier spacing, the movement speed of the access network device, the height of the access network device, the height time advance of the access network device and the TA scaling factor is achieved due to a change in another parameter, for example, the frequency for adjusting the TA or the speed of movement of the terminal, and if the correspondence changes only in numerical value, the correspondence also falls within the protection scope of this application.

table 2

Altitude at which the access network device is located (km) Access network device movement speed Time advance in height
TA(h) TA scaling factor k (120 kHz subcarrier spacing) TA scaling factor k (60 kHz subcarrier spacing) TA scaling factor k (30 kHz subcarrier spacing) TA scaling factor k (15 kHz subcarrier spacing) 300 7.72276235 2 5.120673 2.560337 1.280168 0.640084 400 7.665521994 2.666667 5.084037 2.542019 1.271009 0.635505 500 7.609535837 3.333333 5.048204 2.524102 1.262051 0.631025 600 7.554758737 4 5.013144 2.506572 1.253286 0.626643 700 7.501147793 4.666667 4.978831 2.489416 1.244708 0.622354 800 7.448662207 5.333333 4.945238 2.472619 1.23631 0.618155 900 7.397263151 6 4.912341 2.45617 1.228085 0.614043 1000 7.346913647 6.666667 4.880115 2.440057 1.220029 0.610014 1100 7.297578456 7.333333 4.848538 2.424269 1.212135 0.606067 1200 7.249223971 8 4.817589 2.408795 1.204397 0.602199 1300 7.201818127 8.666667 4.787248 2.393624 1.196812 0.598406 1400 7.155330305 9.333333 4.757494 2.378747 1.189373 0.594687 1500 7.109731253 10 4.728308 2.364154 1.182077 0.591039 1600 7.064993008 10.66667 4.699674 2.349837 1.174919 0.587459 1700 7.021088823 11.33333 4.671574 2.335787 1.167893 0.583947 1800 6.977993101 12 4.643991 2.321995 1.160998 0.580499 1900 6.935681329 12.66667 4.616909 2.308455 1.154227 0.577114 2000 6.894130024 13.33333 4.590315 2.295157 1.147579 0.573789 2100 6.853316677 14 4.564193 2.282096 1.141048 0.570524 2200 6.81321969 14.66667 4.538529 2.269264 1.134632 0.567316 2300 6.773818376 15.33333 4.51331 2.256655 1.128328 0.564164 2400 6.735092822 16 4.488524 2.244262 1.122131 0.561066 2500 6.697023939 16.66667 4.464159 2.232079 1.11604 0.55802 2600 6.659593375 17.33333 4.440202 2.220101 1.11005 0.555025 2700 6.62278349 18 4.4166425 2.208321 1.10416 0.55208 2800 6.586577318 18.66667 4.393468 2.196734 1.098367 0.549184 2900 6.550958533 19.33333 4.370671 2.185335 1.092668 0.546334 3000 6.515911425 20 4.348239 2.17412 1.08706 0.54353 3100 6.481420862 20.66667 4.326164 2.163082 1.081541 0.540771 3200 6.447472268 21.33333 4.304439 2.152218 1.076109 0.538054 3300 6.414051598 22 4.283045 2.141522 1.070761 0.535381 3400 6.381145309 22.66667 4.261984 2.130992 1.065496 0.532748 3500 6.34874034 23.33333 4.241243 2.120622 1.060311 0.530155 3600 6.316824089 24 4.220815 2.110408 1.055204 0.527602 3700 6.285384395 24.66667 4.200693 2.100346 1.050173 0.525087 3800 6.254409515 25.33333 4.180867 2.090434 1.045217 0.522608 3900 6.223888108 26 4.161332 2.080666 1.040333 0.520167 4000 6.193809215 26.66667 4.142081 2.07104 1.03552 0.51776 4100 6.164162246 27.33333 4.123105 2.061553 1.030776 0.515388 4200 6.134936961 28 4.1044 2.0522 1.0261 0.51305 4300 6.106123459 28.66667 4.085958 2.042979 1.02149 0.510745 4400 6.077712159 29.33333 4.067774 2.033887 1.016943 0.508472 4500 6.049693791 thirty 4.049841 2.02492 1.01246 0.50623 4600 6.022059379 30.66667 4.032154 2.016077 1.008038 0.504019 4700 5.994800234 31.33333 4.014707 2.007353 1.003677 0.501838 4800 5.967907939 32 3.997495 1.998747 0.999374 0.499687 4900 5.941374338 32.66667 3.980512 1.990256 0.995128 0.497564 5000 5.915191528 33.33333 3.963754 1.981877 0.990939 0.495469 5100 5.889351847 34 3.947216 1.973608 0.986804 0.493402 5200 5.863847865 34.66667 3.930892 1.965446 0.982723 0.491361 5300 5.838672375 35.33333 3.914779 1.957389 0.978695 0.489347 5400 5.813818387 36 3.898871 1.949436 0.974718 0.487359 5500 5.789279115 36.66667 3.883165 1.941582 0.970791 0.485396 5600 5.765047973 37.33333 3.867656 1.933828 0.966914 0.483457 5700 5.741118565 38 3.85234 1.92617 0.963085 0.481543 5800 5.717484682 38.66667 3.837214 1.918607 0.959303 0.479652 5900 5.69414029 39.33333 3.822272 1.911136 0.955568 0.477784 6000 5.671079526 40 3.807512 1.903756 0.951878 0.475939

[00153] Similarly, based on the embodiment shown in Table 2, in order to reduce the amount of memory occupied when the terminal device stores the table, in this embodiment, the access network device heights can be further classified into different levels, and each level corresponds to one the maximum scaling factor k TA. In addition, the data in the table can be further processed by rounding up or to the nearest 0.5 to reduce storage space. For example, Table 2.1 and Table 2.2 show two possible ways to compress Table 2.

Table 2.1

Altitude at which the access network device is located (km) Access network device movement speed Height advance
TA(h) TA scaling factor k (120 kHz subcarrier spacing) TA scaling factor k (60 kHz subcarrier spacing) TA scaling factor k (30 kHz subcarrier spacing) TA scaling factor k (15 kHz subcarrier spacing) 300-600 7.72-7.55 2.00-4.00 6 3 2 1 700-4700 7.50-5.99 4.67-31.33 5 3 2 1 4800-6000 5.97-5.67 32.00-40 4 2 1 1 ... ... ... ... ... 1 1

Table 2.2

Altitude at which the access network device is located (km) Access network device movement speed Height advance
TA(h) TA scaling factor k (120 kHz subcarrier spacing) TA scaling factor k (60 kHz subcarrier spacing) TA scaling factor k (30 kHz subcarrier spacing) TA scaling factor k (15 kHz subcarrier spacing) 300-600 7.72-7.55 2.00-4.00 5.5 3 1.5 1 700-2300 7.5-6.77 4.67-15.33 5 2.5 1.5 1 2400-4700 6.74-5.99 16.00-31.33 4.5 2.5 1.5 1 4800-6000 5.97-5.67 32.00-40 4 2 1 1 ... ... ... ... ... 1 1

[00154] Optionally, in a third possible specific implementation of determining the TA scaling factor k in step S202, the terminal may determine the TA scaling factor k based on the format of the random access preamble used by the terminal in the random access process.

[00155] In the tag random access process, the tag sends a random access preamble to the access network device to request to establish a connection relationship with the access network device. For cells with different coverage radius of the access network device, the formats of the random access preambles sent by the terminal device to the access network device during the random access process are different. For example, in a random access process, a terminal device in a cell with a radius of 5 km needs to send a format 1 random access preamble to the access network device. However, in the random access process, a terminal device in a cell with a radius of 10 km must send a format 2 random access preamble to the access network device. In addition, the TA adjustment ranges for cells with different radii are different. The TA adjustment range for a cell with a large radius is larger, and the TA adjustment range for a cell with a smaller radius is smaller. Therefore, when the TA of the terminal is determined, a correspondence can be established between the TA adjustment range of the terminal, namely the TA scaling factor k, and the random access preamble format, so that the terminal can determine the appropriate TA scaling factor k based on the random access preamble format, used in the random access process.

[00156] Optionally, the correspondence between the TA scaling factor k and the random access preamble format may alternatively be stored in the access network device and/or terminal device in the form of a table. If the terminal stores the table, after determining the format of the random access preamble used by the terminal in the random access process, the terminal may determine the appropriate TA scaling factor k based on the format of the random access preamble. If the terminal device does not store the table, during the random access process, the terminal device sends a random access preamble to the access network device, and after determining the appropriate TA scaling factor k based on the random access preamble format, the access network device can return the TA scaling factor k to the terminal device.

[00157] In particular, in the above embodiment, in the random access process, the length of the cyclic prefix (Cyclic Prefix, CP) of the random access preamble format sent by the terminal to the access network device determines the possible TA adjustment range of the terminal. In addition, it is determined whether to input an additional TA scaling factor when TA is determined, and a specific value of the TA scaling factor is determined. Therefore, the scaling factor k can be determined based on the random access format used.

[00158] The TA scaling factor k may be determined based on the maximum random access preamble format length CP configured for a cell or beam, such that the TA scaling factor value is shared by the entire cell or beam. Alternatively, the scaling factor k can be determined based on the random access preamble format length CP selected by each user (group), so that different users can use different TA scaling factors k to minimize the loss of accuracy caused by using the scaling factor.

[00159] Optionally, in a fourth possible specific implementation of determining the TA scaling factor k in step S202, the terminal may determine different TA scaling factors k based on different satellite types of the access network device being accessed.

[00160] If the access network device is a satellite base station, the satellite type may be low orbit, medium orbit, high orbit, and the like, which are classified by the satellite base station based on the operating altitude. Satellites operating in different orbits have different operating parameters, so it is necessary to set different TA scaling factors. After accessing the satellite base station, the terminal can determine the type of the satellite base station, and then determine the operating parameter, such as the path height and the total round trip delay of the satellite base station, based on the type of the satellite base station, and finally determine based on the operating parameter of the satellite base station, the TA scaling factor corresponding to the current satellite base station. Optionally, the satellite type, the operating parameter, and the correspondence between the operating parameter and the TA scaling factor may be stored in the access network device and/or terminal device in the form of a table. Alternatively, the access network device and/or terminal device may directly store a table used to indicate the correspondence between satellite type and TA scaling factor. If the tag stores the table, after accessing the satellite base station, the tag can directly determine the appropriate TA scaling factor from the table based on the type of the satellite base station.

[00161] Optionally, in the above embodiments of this application, the method for determining the TA scaling factor k of a tag may be agreed jointly by the tag and the access network device in advance to ensure that the TA obtained by calculation by the tag is sufficient to cover the adjustment range of the TA.

[00162] Optionally, in another embodiment of this application, when adjusting TA using the formula TA ₂ = TA ₁ +k∙(T _A -31)∙16∙64/2 ^μ in step S203, the terminal may further add a parameter offset offset to TA adjustment, i.e. can adjust TA using a formula. TA ₂ = TA ₁ +k∙(T _A -31)∙16∙64/2 ^μ +offset. Thus, the adjustment range of the TA of the terminal is further extended. The offset parameter may be a fixed value, or may be obtained using a function associated with the TA adjustment parameter k, or may be obtained using a function associated with the height at which the access network device is located.

[00163] In addition, the method for determining a TA for a tag provided in the above embodiment takes into account the mobility of the tag and the access network device. When the access network device is a satellite base station, since the movement path of the satellite base station is relatively fixed, when the terminal is in a static state, the TA change law of the terminal caused by the movement of the satellite base station is also fixed. Therefore, if the terminal has received information such as the satellite base station's trajectory height and the location of the terminal, the indication of the satellite base station may not be required, and the terminal directly determines the TA adjustment to be adjusted and precompensates the TA.

[00164] In particular, FIG. 8 is a schematic block diagram of an embodiment of a method for determining a TA for a terminal according to this application. The method for determining the TA for the terminal shown in FIG. 8 includes the following steps.

[00165] S301: If the terminal is in a static state, the drift rate TA of the terminal is determined, where the drift rate TA is used to indicate the adjustment of the TA that is in the cell where the terminal is located and is caused by movement of the access network device.

[00166] In a particular implementation, in step S301, the tag may determine the drift rate TA of the tag according to a third mapping relationship, where the third mapping relationship includes a correspondence between the Doppler frequency shift of at least one access network device and the drift rate TA of the tag .

[00167] For example, the terminal may determine the drift rate TA of the terminal based on the Doppler frequency shift of the access network device obtained by measuring where D _TA = -λFd and D _{TA is} the drift rate of TA, λ is the wavelength of the wireless communication signal sent by the access network device, and Fd is the Doppler frequency shift. Fig. 9 is a schematic diagram of the Doppler frequency shift of the access network device according to this application, and FIG. 10 is a schematic diagram of the drift rate TA of a terminal in accordance with this application. Based on the correspondence between FIG. 9 and FIG. 10, it can be learned that the Doppler frequency shift of the access network device is inversely proportional to the drift rate TA of the terminal.

[00168] S302: The terminal determines the fourth TA based on the drift rate of the TA, the third TA, the TA adjustment parameter, and the subcarrier spacing parameter, where the third TA is the TA used when the terminal communicates with the access network device before determining the fourth TA.

[00169] In particular, the terminal may calculate the fourth TA using the formula TA ₄ =TA ₃ +∆N _TA +∆N' _TA ∙∆t, where ∆N _TA =(T _A -31)∙16∙64/2 ^μ , where T _A is the TA adjustment parameter sent by the access network device, ∆N' _TA is the TA adjustment determined in step S301, Δt=t1-t0, t0 is the time at which the terminal device receives the TA adjustment parameter, and t1 is this is the time at which the terminal must send the uplink communication data to the access network device.

[00170] S303: The terminal communicates with the access network device using the fourth TA.

[00171] Finally, the tag communicates with the access network device using the fourth TA defined in the previous steps, where communication means that the tag needs to send uplink transmission data to the access network device in the fourth TA time period in advance. It can be understood that in the embodiment shown in FIG. 8, before determining the fourth TA, the terminal device sends uplink transmission data to the access network device for the third TA time period in advance. After determining the fourth TA in step S302, the terminal device sends uplink transmission data to the access network device for the fourth time period TA in advance.

[00172] For example, FIG. 11 is a schematic diagram of a fourth TA detection by a terminal in accordance with this application. As shown in FIG. 11, after the terminal uses the TA adjustment parameter received at time t0 and indicated by the satellite base station to determine the TA adjustment ΔTA_1, and before the satellite base station indicates the next TA adjustment parameter to determine the TA adjustment ΔTA_2, the terminal the device predicts that the adjustment of TA in the future time period from t0 to t1 is ΔTA';, calculates the fourth TA using the formula TA ₄ =TA ₃ +∆TA_1+∆TA'∙(t0-t1) and uses the fourth TA to send communication data uplink to the satellite base station at time t1.

[00173] Optionally, after the terminal precompensates the TA based on the Doppler frequency shift, the TA deviation still exists. Therefore, the satellite base station can estimate the corresponding TA deviation based on the received uplink signal of the terminal device and send the corresponding TA deviation to the terminal device in order to maintain the TA compensation accuracy of the terminal device.

[00174] Finally, in the TA determination method for a terminal provided in this embodiment, the terminal may pre-compensate the TA adjustment based on a parameter such as Doppler to avoid frequent TA adjustment indications from the satellite base station and reduce costs. resources. In addition, since the communication delay between the satellite base station and the terminal is relatively large, performing pre-compensation using this embodiment can reduce the TA error introduced by the delay when the satellite base station indicates to adjust TA.

[00175] It should be noted that the embodiment shown in FIG. 8 may be implemented independently, or the embodiment shown in FIG. 8 may be based on the embodiment shown in FIG. 7. After the access network device sends the TA adjustment parameter to allow the terminal device to adjust the TA, and before the access network device sends the TA adjustment parameter next time, the terminal device may adjust the TA in the manner shown in FIG. 8, no indication from the access network device.

[00176] Optionally, in the embodiment shown in FIG. 8, in another possible implementation of determining the TA drift rate of the tag in step S301, the tag may determine the TA drift rate of the tag based on the correspondence between the cell in which the tag is located and the TA drift rate. The drift rate TA caused by the movement of the satellite base station is related to the geographic location of the terminal. The TA drift rate of a terminal located closer to the satellite base station changes more, and the TA drift rate of the terminal located further from the satellite base station changes less or even tends to be constant. Therefore, in this embodiment, the satellite base station can separate cells based on the TA drift rate change states, and broadcast in each cell the TA drift rate corresponding to the cell, so that the terminal determines the TA drift rate after receiving the broadcast of the satellite base station.

[00177] For example, FIG. 12 is a schematic diagram of 1 cell division based on drift rate TA according to this application. In the example shown in FIG. 12, in order to reduce the compensation error TA, different cells in the coverage area of the satellite base station O have different radii. The radius of the cell directly below the satellite base station O is minimal, and the drift speed TA of the cell is referred to as ΔTA 1'. The drift rate of a TA cell further away from the satellite base station O is denoted as ΔTA 2'. The radius of the outermost cell in the coverage area of the satellite base station O is the maximum, and the drift rate of the TA cell is denoted as ΔTA 3'.

[00178] In addition, in the example shown in FIG. 12, in order to reduce the cost of signaling indicating the TA drift rate of the access network device to the terminal, in this embodiment, the TA drift rate may be further associated with the cell ID/indication parameter of the access network device in the implicit indication. Thus, the tag can determine, based on the ID of the cell in which the tag is located, the drift rate TA of the cell, and the access network device need not specifically send the TA drift rate to the terminal.

Table 3

Display Parameter/Cell ID TA drift speed 1 |ΔTA 1'| 2 |ΔTA 2'| 3 |ΔTA 2'| ... ... k |ΔTAk'|

[00179] For example, as shown in Table 3, a terminal may store a mapping relationship between a TA drift rate and a cell ID in a table, where different cell IDs correspond to different TA drift rates. The terminal may query the table based on the indication parameter broadcast by the satellite base station or the detected cell ID to obtain a specific drift rate TA. When the satellite base station in FIG. 12 moves to the left in the figure, the drift TA velocities on the left are all positive, the drift velocities TA on the right are all negative, and the TA drift velocities stored in table 3 are only absolute values. Therefore, the same or different indication parameters may be used for the TA drift rates of opposite symbols. When the indication parameters are the same, the terminal can determine whether the drift rate TA is positive or negative based on the estimation of the Doppler frequency shift of the satellite base station in order to reduce the storage space occupied by Table 3. For example, TA is negative when the Doppler frequency shift is positive, and TA is positive when the Doppler shift is negative.

[00180] Optionally, based on the cell division based on the drift rate TA shown in FIG. 12, in order to achieve the TA error accuracy required in the current 5G NR, the cell radius directly below the radar base station should be set to 10 km at the time of cell separation. However, the cell radius is too small for a satellite, and different cell radius designs increase the design and implementation complexity. Therefore, according to the embodiment shown in FIG. 12, this application further provides a division method for different TA drift rates in each cell. Fig. 13 is a schematic diagram 2 of cell division based on drift rate TA according to this application. As shown in FIG. 13, in cells separated by a satellite base station, cells with different relative locations correspond to one or more drift rates TA. Different regions in a cell, including a plurality of TA drift rates, correspond to different TA drift rates. Therefore, the satellite base station can broadcast all the TA drift rates in the cell in the cell, and terminals in different locations can select, based on a parameter such as Doppler frequency shift, the corresponding TA drift rate in the cell where the terminals are located. A cell directly below a satellite base station has a minimum radius, and TA drift rates that can be used by terminals in the cell include ΔTA 11', ΔTA 12', ΔTA 13', -ΔTA 11', -ΔTA 12' and -ΔTA 13'. A cell outside the cell directly below the satellite base station has a slightly larger radius. Based on the different movement directions of the satellite base station, the TA drift rates that may be separately used by the terminals in the cell include ΔTA 14', ΔTA 15', and ΔTA 16', or include -ΔTA 14', -ΔTA 15', and -ΔTA 16'. A cell located at the maximum coverage boundary of a satellite base station has a maximum radius. Based on the different directions of movement of the satellite base station, the TA drift rates that can be separately used by the terminals located in the cell include ΔTA 1k' or include -ΔTA 1k'. Therefore, in this embodiment, the terminal can perform pre-compensation to reduce the TA error caused by the delay when the satellite base station indicates to adjust the TA. In addition, when a cell corresponding to a satellite base station is divided, the cell radius does not need to be limited based on the drift rate TA. This reduces the complexity of design and implementation.

[00181] In the embodiments presented in the aforementioned embodiments of this application, the methods provided in this application are described and explained from the point of view of an access network device and a terminal device. To implement the functions in the method provided in the embodiments of this application, the access network device and the terminal device may include a hardware structure and/or a software module, as well as implement functions in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. . Whether the function in the above functions is performed by a hardware structure, a software module, or a combination of a hardware structure and a software module depends on particular applications and design constraints of the technical solutions.

[00182] FIG. 14 is a schematic diagram of the structure in an embodiment of a terminal device in accordance with this application. The terminal device is configured to perform the method of the terminal device in the above embodiment. As shown in FIG. 14, the terminal provided in this embodiment includes a transceiver unit 1401, a parameter determination unit 1402, and a TA determination unit 1403. The transceiver module 1401 is configured to receive the TA adjustment parameter from the access network device, where the TA adjustment parameter is used to indicate the TA adjustment of the terminal device. The parameter determining unit 1402 is configured to determine the TA scaling factor of the tag, the tag's subcarrier spacing parameter, and the first TA used when the tag communicates with the access network device prior to receiving the TA adjustment parameter, where the TA scaling factor is used to perform scaling processing when adjusting the TA of the terminal. The TA determination module 1403 is further configured to determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The transceiver module 1401 is further configured to communicate with the access network device using the second TA.

[00183] The terminal device provided in this embodiment may be configured to perform the method performed by the terminal device in the method shown in FIG. 7. The implementations and operating principles of the terminal are the same, and the details are not described again.

[00184] Optionally, the TA determination module 1403 is specifically configured to calculate the TA₂ using the TA formula₂=TA₁+k∙(T_A-31)∙16∙64/2^μ, where TA₁ is the first TA, T_A - adjustment parameter TA, k - scaling factor TA, 2^μ - subcarrier spacing parameter, ∆f=2^μ∙15[kHz] and Δf - subcarrier spacing of the terminal device.

[00185] Optionally, the parameter determination module 1402 is specifically configured to determine a TA scaling factor based on the maximum movement speed of the tag, the movement speed of the access network device, and the frequency at which the access network device instructs the tag to adjust the TA.

[00186] Optionally, the parameter determination module 1402 is specifically configured to calculate the TA scaling factor k using the formula 2(v₁+v₂)/f_TA/c=k∙32∙16∙64∙T_c/8_,where v₁ - maximum speed of the terminal device, v_2-speed of movement of the access network device, f_TA - the frequency with which the access network device tells the terminal to adjust TA, c is the speed of light, and T_c - base unit of time_.

[00187] Optionally, the parameter determination module 1402 is further configured to determine whether the TA adjustment of the terminal processed by the TA scaling factor matches the preset condition, and if the TA adjustment matches the preset condition, determine a second TA based on the TA adjustment parameter , the TA scaling factor, the subcarrier spacing parameter, and the first TA.

[00188] Optionally, the parameter determination module 1402 is specifically configured to determine the TA scaling factor based on the speed of the access network device, the height of the access network device, and the height advance of the access network device.

[00189] Optionally, the parameter determination module 1402 is specifically configured to determine, by searching for the first display ratio, a scaling factor TA corresponding to the speed of movement of the access network device, the height at which the access network device is located, and the time advance in height of the access network device . The first mapping relationship includes a correspondence between at least one of an access network device moving speed, an access network device height, and an access network device height advance, and a TA scale factor.

[00190] Optionally, the parameter determination module 1402 is specifically configured to determine, by searching for the second mapping ratio, the scaling factor TA corresponding to the subcarrier spacing of the terminal device, the speed of movement of the access network device, the height at which the access network device is located, and the time advance height of the access network device. The second mapping relationship includes a correspondence between at least one of the tag subcarrier spacing, the access network device speed, the access network device height and the access network device height advance, and the TA scaling factor.

[00191] Optionally, the parameter determination module 1402 is specifically configured to determine the TA scaling factor based on the format of the random access preamble used by the terminal during random access to the access network device.

[00192] Optionally, the TA determination module 1403 is further configured to determine the second TA based on the TA offset parameter, the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA, where the TA offset parameter is used to perform offset processing in the adjustment of the TA of the terminal devices.

[00193] Optionally, the transceiver module 1401 is further configured to receive indication information sent by the access network device, where the indication information is used to indicate the total delay of the cell in which the tag is located. The parameter determination module 1402 is further configured to determine the overall delay.

[00194] The terminal device provided in this embodiment may be configured to execute the method performed by the terminal device in the method shown in FIG. 3. The implementations and operation principles of the terminal device are the same, and the details are not described again.

[00195] Optionally, the transceiver module 1401 is further configured to: when the terminal device accesses the access network device for the first time, to receive the initial TA parameter from the access network device. The TA determination module 1403 is further configured to determine the initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter.

[00196] Optionally, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[00197] Optionally, the parameter determination module 1402 is further configured to: if the terminal is in a static state, determine the drift rate TA of the terminal, where the drift rate TA is used to indicate the TA adjustment that is being performed in the cell where the terminal resides, and caused by the movement of the access network device.

[00198] The TA determination module 1403 is further configured to determine a fourth TA based on the TA drift rate, a third TA, a TA adjustment parameter, and a subcarrier spacing parameter, where the third TA is the TA used when the terminal communicates with the access network device prior to determining the fourth TA. The transceiver module 1401 is further configured to communicate with the access network device using the fourth TA.

[00199] Optionally, the TA determination module 1403 is further configured to calculate a fourth TA using the formula TA ₄ =TA ₃ +∆N _TA +∆N' _TA ∙∆t, where ∆N _TA =(T _A -31)∙16 ∙64/2 ^μ , T _A is the TA adjustment parameter sent by the access network device, ∆N' _TA is the TA adjustment, Δt=t1-t0, t0 is the time at which the terminal device receives the TA adjustment parameter, and t1 is the time at which the terminal should send the uplink communication data to the access network device.

[00200] Optionally, the parameter determination module 1402 is further configured to determine the TA drift rate of the tag according to a third mapping relationship, where the third mapping relationship includes a correspondence between the Doppler frequency shift of at least one access network device and the TA drift rate of the tag. devices.

[00201] The terminal device provided in this embodiment may be configured to perform the method performed by the terminal device in the method in the above embodiments. The implementations and operating principles of the terminal are the same, and the details are not described again.

[00202] FIG. 15 is a schematic diagram of a structure in an embodiment of an access network device according to this application. The access network device is configured to perform the method of the access network device in the above embodiment. As shown in FIG. 15, the access network device provided in this embodiment includes a transceiver unit 1501 and a determination unit 1502. The determining module 1502 is configured to determine a TA adjustment parameter of the tag, where the TA adjustment parameter is used to indicate the TA adjustment of the tag. The transceiver module 1501 is configured to send the TA adjustment parameter to the terminal device to allow the terminal device to determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA, where the TA scaling factor is used to perform TA adjustment scaling processing terminal device, and the first TA is the TA used when the terminal device communicates with the access network device before the terminal device receives the TA adjustment parameter.

[00203] The access network device provided in this embodiment may be configured to perform the method performed by the access network device in the method shown in FIG. 7. The implementations and operating principles of the terminal device are the same, and the details are again not described.

[00204] Optionally, the transceiver module 1501 is further configured to send indication information to the terminal device, where the indication information is used to indicate the total delay of the cell in which the terminal device resides. Optionally, the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located.

[00205] Optionally, the transceiver module 1501 is specifically configured to: broadcast the total delay in the cell in which the terminal is located; or broadcasting the height time advance in the coverage area of the access network device and broadcasting the angle time advance in the cell in which the terminal device is located.

[00206] The access network device provided in this embodiment may be configured to perform the method performed by the access network device in the method in the above embodiments. The implementations and operating principles of the terminal are the same, and the details are not described again.

[00207] The division into modules in the embodiments of this application is an example, is simply a division into logical functions, and may be another division in the actual implementation. In addition, the functional modules in the embodiments of this application may be integrated into one processor, or each of the modules may exist separately physically, or two or more modules may be integrated into one module. An integrated module may be implemented in hardware or may be implemented in a software function module.

[00208] FIG. 16 is a schematic diagram of the structure in an embodiment of the communication equipment according to this application. The communication equipment shown in Fig. 16 may be configured to serve as a terminal device in any of the above embodiments of this application or an access network device in any of the above embodiments to implement the above TA determination method for the terminal device. The communications hardware 1000 includes a communications interface 1010, a processor 1020, and a memory 1030. The communications interface 1010 may be a transceiver, circuitry, bus, or other form of interface and is configured to communicate with another device using a transmission medium. Communication interface 1010, processor 1020 and memory 1030 are connected. Connections in the embodiments of this application are indirect connections or communication connections between devices, blocks or modules, can be implemented in electronic, mechanical or other forms and are used to exchange information between devices, blocks or modules.

[00209] In this embodiment of this application, the specific communication medium between the communication interface 1010, the processor 1020, and the memory 1030 is not limited. In this embodiment of this application, communication interface 1010, memory 1030, and processor 1020 are connected via bus 1040 in FIG. 16. The tire is represented by the bold line in FIG. 16. The method of connecting other components is described simply schematically and is not restrictive. The bus can be divided into address bus, data bus, control bus and the like. For ease of presentation, only one bold line is used to represent the tire in FIG. 16, but this does not mean that there is only one bus or only one type of bus.

[00210] In a possible implementation, if the communications equipment shown in FIG. 16 is a terminal device, the terminal device may be configured to implement the methods performed by the terminal device in the aforementioned embodiments of this application.

[00211] For example, the communication interface 1010 is configured to receive the TA adjustment parameter from the access network device and send the TA adjustment parameter to the processor, where the TA adjustment parameter is used to indicate the TA adjustment of the terminal device. The memory 1030 stores instructions and the processor 1020 calls and executes instructions to allow the processor 1020 to determine, upon receipt of the TA adjustment parameter, the TA scaling factor of the tag, the tag's subcarrier spacing parameter, and the first TA used when the tag communicates with a network device access before receiving the adjustment parameter TA. The processor 1020 further determines the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA. The communication interface 1010 further communicates with the access network device using the second TA. Alternatively, for example, the communication interface 1010 is further configured to receive indication information sent by the access network device and send the indication information to the processor. The indication information is used to indicate the total delay of the cell in which the terminal resides. The processor 1020 is further configured to: upon receiving the indication information, determine a total delay based on the indication information. The communication interface 1010 is further configured to: when the tag accesses the access network device for the first time, receive the initial TA from the access network device and send the initial TA to the processor. The processor 1020 is further configured to: upon receiving the initial TA parameter, determine the initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter.

[00212] For a specific implementation of the above example, refer to the detailed description in the example corresponding to the above method. Details are not described here again.

[00213] In another possible implementation, if the communications equipment shown in FIG. 16 is an access network device, the access network device may be configured to implement the methods performed by the access network device in the above embodiments of this application.

[00214] For example, when processor 1020 calls and executes instructions stored in memory 1030, processor 1020 is able to determine the TA adjustment parameter of the tag and sends the TA adjustment parameter to communication interface 1010. Upon receiving the TA adjustment parameter, the communication interface 1010 sends the TA adjustment parameter to the terminal device. Alternatively, for example, the communication interface 1010 is further configured to send indication information to the terminal device, where the indication information is used to indicate the total delay of the cell in which the terminal device is located.

[00215] For a specific implementation of the above example, refer to the detailed description in the example corresponding to the above method. Details are not described here again.

[00216] In embodiments of this 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 logic device or a transistorized logic device, or a discrete hardware component, and may implement or execute methods , steps and flowcharts disclosed in the embodiments of this application. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of the method disclosed with reference to embodiments of this application may be performed directly by a hardware processor or may be performed using a combination of hardware in the processor and a software module.

[00217] In this embodiment of this application, the memory may be non-volatile memory, such as a hard disk drive (HDD) or solid state drive (solid-state drive, SSD), or may be volatile memory (volatile memory), for example, RAM (random access memory, RAM). Memory is any other medium that can carry or store expected program code in the form of an instruction structure or data structure and that can be accessed by, but is not limited to, a computer. Alternatively, the memory in embodiments of this application may be circuitry or any other hardware that can implement a storage function and is configured to store program instructions and/or data.

[00218] All or some of the above methods in the embodiments of this application may be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, all or some of the embodiments may be implemented in the form of a computer program product. A computer program product includes one or more computer instructions. When the instructions of the computer program are downloaded and executed on the computer, the procedure or functions according to the embodiments of the present invention are wholly or partially generated. The computer may be a general purpose computer, a special purpose computer, a computer network, a network device, user equipment, or other programmable device. The computer instructions may be stored on a computer-readable storage medium or may be transferred from a computer-readable storage medium to another computer-readable storage medium. For example, computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center by wire (for example, coaxial cable, optical fiber, or digital subscriber line, abbreviated DSL)) or wireless (eg infrared, radio or microwave) method. A computer-readable storage medium may be any usable medium accessible to a computer, or a data storage device, such as a server or data center, that combines one or more usable media. The medium used may be a magnetic medium (eg, a floppy disk, hard disk, or magnetic tape), an optical medium (eg, a digital video disc (DVD for short)), a semiconductor medium (eg, an SSD), and the like.

[00219] Obviously, a person skilled in the art can make various modifications and changes to this application without going beyond the scope of this application. This application is intended to cover these modifications and variations of this application, provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.

Claims (49)

1. A method for determining the timing advance (TA) for a terminal device, including: receiving a TA adjustment parameter from the access network device, wherein the TA adjustment parameter is used to indicate the TA adjustment of the terminal device; determining a TA scaling factor of the tag, a subcarrier spacing parameter of the tag, and a first TA used when the tag communicates with an access network device before receiving the TA adjustment parameter, the TA scaling factor being used to perform TA adjustment scaling processing of the terminal; And determining a second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA; wherein the determination of the scaling factor TA includes the steps of: determining a TA scaling factor based on the maximum moving speed of the terminal device, the moving speed of the access network device, and the frequency with which the access network device instructs the terminal device to adjust the TA; or determining a scaling factor TA based on the speed of movement of the access network device, the height of the access network device, and the height advance of the access network device; or determining a TA scaling factor based on a random access preamble format used by the terminal device in a random access process to the access network device; or determining a TA scaling factor based on the access network device attribute information. 2. The method of claim 1, wherein determining the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA includes: calculation of TA ₂ according to the formula TA ₂ = TA ₁ +k⋅(T _A -31)⋅16⋅64/2 ^μ , where TA ₁ is the first TA, T _A is the TA adjustment parameter, k is the TA scaling factor, 2 ^μ is the subcarrier spacing parameter, Δf=2 ^μ ⋅15[kHz] and Δf is the terminal subcarrier spacing. 3. The method of claim 1 or 2, wherein determining the TA scaling factor based on the maximum moving speed of the tag, the moving speed of the access network device, and the frequency at which the access network device instructs the tag to adjust the TA, includes: calculating the TA scaling factor k using the formula 2(v ₁ +v ₂ )/f _TA /c=k⋅32⋅16⋅64⋅T _c /8, where v ₁ is the maximum movement speed of the terminal, v ₂ is the movement speed of the access network device, f _TA is the frequency with which the access network device instructs the terminal to adjust TA, c is the speed of light, and T _c is the base unit of time. 4. The method according to any one of paragraphs. 1-3, wherein before receiving the adjustment parameter TA from the access network device, the method further comprises: receiving indication information sent by the access network device, the indication information being used to indicate the total delay of the cell in which the terminal device is located; And determining a total delay based on the indication information. 5. The method of claim 4, wherein before receiving the adjustment parameter TA from the access network device, the method further includes: when the terminal accesses the access network device for the first time, obtaining an initial TA parameter from the access network device; And determining an initial TA based on the total delay, the initial TA parameter, and the subcarrier spacing parameter. 6. The method according to claim 4 or 5, in which the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located. 7. The method according to any one of paragraphs. 1-6, additionally containing: if the terminal is in a static state, determining the drift rate TA of the terminal, wherein the drift rate TA is used to indicate the adjustment of the TA, which is performed in the cell in which the terminal is located, and is caused by the movement of the access network device; And determining a fourth TA based on the TA drift rate, a third TA, a TA adjustment parameter, and a subcarrier spacing parameter, wherein the third TA is the TA used when the terminal communicates with the access network device before determining the fourth TA. 8. The method of claim 7, wherein determining the fourth TA based on the TA drift rate, the third TA, the TA adjustment parameter, and the subcarrier spacing parameter includes: calculation of the fourth TA using the formula TA ₄ =TA ₃ +ΔN _TA +ΔN' _TA ⋅Δt, where ΔN _TA =(T _A -31)⋅16⋅64/2 ^μ , TA is the TA adjustment parameter sent by the access network device , ΔN' _TA is the TA adjustment, Δt=t1-t0, t0 is the time at which the terminal device receives the TA adjustment parameter, and t1 is the time at which the terminal device should send uplink communication data to the access network device. 9. The method of claim 7 or 8, wherein determining the drift rate TA of the terminal includes: determining the drift rate TA of the terminal according to the third mapping relationship, wherein the third mapping relationship comprises a correspondence between the Doppler frequency shift of at least one access network device and the drift rate TA of the terminal. 10. A method for determining the timing advance (TA) for a terminal device, including: determining a TA adjustment parameter of the terminal, wherein the TA adjustment parameter is used to indicate a TA adjustment of the terminal; And sending the TA adjustment parameter to the terminal device to allow the terminal device to determine the second TA based on the TA adjustment parameter, the TA scaling factor, the subcarrier spacing parameter, and the first TA, wherein the TA scaling factor is used to perform scaling processing for TA adjustment of the terminal device, and the first TA is the TA used when a terminal communicates with an access network device prior to receiving a TA adjustment parameter, and the TA scaling factor is determined based on the maximum movement speed of the terminal device, the movement speed of the access network device, and the frequency with which the access network device instructs the terminal to adjust the TA, or the scaling factor TA is determined based on the speed of movement of the access network device, the height of the access network device and the time advance in height of the access network device, or the TA scaling factor is determined based on the format of the random access preamble used by the terminal device in the process of random access to the access network device, or the scaling factor TA is determined based on the access network device attribute information. 11. The method of claim 10, further comprising: sending indication information to the terminal device, wherein the indication information is used to indicate the total delay of the cell in which the terminal device is located. 12. The method according to claim 11, in which: the total delay includes the height time advance of the access network device and the angular time advance of the cell in which the terminal is located. 13. The method of claim 12, wherein sending the indication information to the terminal device includes: broadcasting the total delay in the cell in which the terminal is located; or broadcasting the height time advance in the coverage area of the access network device; and broadcasting the angle time advance in the cell in which the terminal device is located. 14. Equipment for determining the timing advance (timing advance, TA) for the terminal device, configured to perform the method according to any one of paragraphs. 1-9. 15. Equipment for determining the timing advance (timing advance, TA) for the terminal device, configured to perform the method according to any one of paragraphs. 10-13. 16. Communication equipment comprising a processor and a memory, the memory storing instructions; and when the processor calls and executes instructions, the hardware is able to perform the method of any one of claims. 1-9. 17. Communication equipment, comprising a processor and a memory, and instructions are stored in the memory; and when the processor calls and executes instructions, the hardware is able to perform the method of any one of claims. 10-13. 18. A computer-readable storage medium containing instructions, wherein when the instructions are executed on a computer, the computer is able to perform the method according to any one of paragraphs. 1-13.

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