WO2020169048A1

WO2020169048A1 - Method for updating timing advance, terminal and base station

Info

Publication number: WO2020169048A1
Application number: PCT/CN2020/075817
Authority: WO
Inventors: 徐晨蕾; 周建伟; 蒋镇军; 罗禾佳
Original assignee: 华为技术有限公司
Priority date: 2019-02-23
Filing date: 2020-02-19
Publication date: 2020-08-27
Also published as: EP3920608A1; US20210392597A1; US11968640B2; US20240236899A1; EP3920608A4; CN114900882B; CN114900882A

Abstract

A method for updating a timing advance, a terminal and a base station. The method comprises: a terminal receives a timing advance (TA) update value and the beam cell number of the beam cell where the terminal is located which are sent by a base station; the terminal acquires corresponding TA compensation information according to the beam cell number; during a TA update period, the terminal carries out TA compensation according to the TA update value and the TA compensation information; and the terminal uses the TA-compensated TA value to send uplink data. By employing the embodiments of the present application, the TA update requirements of a satellite communication system may be met, and uplink interference between users is avoided, thus improving the working performance of the system.

Description

Method, terminal and base station for updating timing advance

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on April 30, 2019, the application number is 201910358327.9, and the invention title is "a method, terminal and network equipment for updating timing advance." Priority of the Chinese patent application filed with the Chinese Patent Office on February 23, 2019, the application number is 201910134729.0, and the invention title is "A method, terminal and base station for updating timing advance". All the contents of the above two previous applications are approved The reference is incorporated in this application.

Technical field

The field of communications technology of the present application particularly relates to a method, terminal and base station for updating timing advance.

Background technique

The 5th Generation Mobile Networks (5G) or future higher-level communication networks not only need to meet the business needs of various industries, but also need to provide wider business coverage. Compared with terrestrial cellular communication, satellite communication has great advantages. Its communication distance is longer, coverage area is larger, and communication frequency band is wider. It can provide users with communication services at any time and at any place. Therefore, the application prospect of satellite communication is very broad, especially in international and domestic communications, emergency rescue and disaster relief, etc. It has unique advantages. According to the orbital height of the satellite, the satellite communication system can be divided into a geostationary orbit (Geostationary Earth Orbit, referred to as GEO) system, a medium orbit (Medium Earth Orbit, referred to as MEO) satellite communication system, and a low earth (Low Earth Orbit, referred to as LEO) satellite Communication Systems. Among them, low-orbit satellites have become a focus of attention because of their advantages such as smaller data propagation delay and power loss, lower launch costs, and global coverage.

When performing uplink transmission, an important feature is that different user equipments (User Equipment, UE for short) have orthogonal multiple access (Orthogonal Multiple Access, OMA) in time and frequency. Do not interfere with each other. In order to ensure the orthogonality of uplink transmission and avoid intra-cell interference, the base station requires signals from different UEs in the same subframe but with different frequency domain resources to arrive at the base station at substantially the same time. As long as the base station receives the uplink data sent by the UE within the range of the Cyclic Prefix (CP), it can decode the uplink data correctly. Therefore, uplink synchronization requires that the signals from different UEs in the same subframe arrive at the base station at all times. Fall within the CP. To ensure time synchronization on the receiving side (base station side), LTE proposes a timing advance (Timing Advance, TA for short) mechanism. For the UE side, the TA is essentially a negative offset (negative offset) between the start time of receiving the downlink subframe and the time of transmitting the uplink subframe. The base station can control the time when uplink signals from different UEs arrive at the base station by appropriately controlling the offset of each UE. For UEs far away from the base station, due to a larger transmission delay, it is necessary to send uplink data earlier than UEs closer to the base station.

Because the distance and transmission delay between the satellite and the UE also change rapidly, the TA change rate of the satellite communication system is much greater than that of the ground communication system. Therefore, a new TA method is needed to meet the ever-changing needs including but not limited to satellite communications.

Summary of the invention

The technical problem to be solved by the embodiments of this application is to provide a method for updating/compensating/adjusting timing advance, terminal network equipment (base station), chip, device, system, storage medium, computer program, data structure, etc., to solve The existing TA update/compensation/adjustment mechanism cannot meet the satellite communication system, and any other problem of TA update/compensation/adjustment requirements in the communication system where the communication delay is long or the update cycle cannot be too frequent.

In the first aspect, an embodiment of the present application provides a method for updating timing advance, which may include:

The terminal receives the update value of the timing advance TA sent by the base station and the beam cell number of the beam cell where the terminal is located;

The terminal obtains corresponding TA compensation information according to the beam cell number;

In the TA update period, the terminal performs TA compensation according to the TA update value and the TA compensation information;

The terminal uses the TA value after TA compensation to send uplink data.

In a possible implementation manner, the TA compensation information includes TA compensation data or reference data used to obtain the TA compensation data;

The TA compensation data includes: the maximum TA deviation and the minimum transmission delay TA deviation of the current beam cell;

The reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the geocentric angle data includes a maximum geocentric angle and a minimum geocentric angle;

Or the reference data includes: Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset.

In a possible implementation manner, the reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the terminal obtains the geocentric angle data according to the geocentric angle data and the satellite orbit height The round-trip transmission delay change rate of the corresponding location;

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data; or

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the position corresponding to the satellite and the geocentric angle data, and the duration of the current TA update period.

In a possible implementation manner, the transmission delay TA deviation obtained by the terminal according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the terminal according to the geocentric angle The transmission delay TA deviation obtained from the minimum geocentric angle in the data is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is the minimum transmission The sum of the delay TA deviation and the minimum update period TA deviation.

In a possible implementation manner, the terminal obtains the round-trip transmission delay change rate corresponding to the geocentric angle data according to the geocentric angle data and the satellite orbit height, specifically according to the following formula:

Among them, T _a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, c represents the speed of light, ω represents the relative angular velocity between the satellite and the user, R represents the radius of the earth, h represents the satellite orbit height, and θ represents the geocentric angle data;

In a possible implementation manner, the terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the geocentric angle data corresponding position, specifically according to the following formula get on:

ΔTA _trans =T _a ′×t _trans ;

Wherein, ΔTA _trans represents the transmission delay TA deviation, and t _trans represents the one-way transmission delay between the satellite and the corresponding position of the geocentric angle data;

In a possible implementation manner, the terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the position corresponding to the satellite and the geocentric angle data, and the duration of the current TA update cycle , According to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

Among them, ΔTA represents the TA deviation, and t _update represents the duration of the current TA update cycle.

In a possible implementation manner, the reference data includes satellite orbital height and Doppler frequency offset data of the current beam cell, and the terminal obtains the round-trip transmission delay of the current position according to the Doppler data and carrier frequency. Rate of change

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location; or

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period;

In a possible implementation manner, the terminal obtains the round-trip transmission delay change rate of the current position according to the Doppler data and the carrier frequency, specifically according to the following formula:

Among them, T _a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, f _c represents the carrier frequency, and f _d represents the Doppler frequency deviation of the current position;

In a possible implementation manner, the terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location, specifically according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

In a possible implementation manner, the terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay at the current location, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

In a possible implementation manner, the terminal performing TA compensation according to the TA update value and the TA compensation information includes:

When the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of any data in the TA compensation data to perform TA compensation;

When the terminal and the satellite are far away from each other, the terminal subtracts the TA update value from the absolute value of any data in the TA compensation data to perform TA compensation.

When the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of the maximum TA deviation to perform TA compensation;

When the terminal and the satellite are far away from each other, the terminal subtracts the TA update value from the absolute value of the minimum transmission delay TA deviation to perform TA compensation.

In a possible implementation manner, the TA compensation data further includes:

The minimum TA deviation and the maximum transmission delay TA deviation of the current beam cell;

The terminal performs TA compensation according to the TA update value and the TA compensation information, including: the terminal calculates each frame according to the TA compensation information and the ratio of the TA update period to the data frame length of the uplink data to be sent Frame TA deviation of data;

The terminal separately performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation.

In a possible implementation manner, when the terminal and the satellite are close to each other, the terminal calculates the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length, including:

The terminal calculates the frame TA deviation according to the maximum TA deviation, the maximum transmission delay TA deviation, and the ratio of the TA update period to the data frame length of the uplink data to be sent;

The terminal performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation, including:

The terminal selects the absolute value of the maximum transmission delay TA deviation and the N times the frame TA deviation to add TA compensation for each frame of data within the TA update period, where N is the sequence number of the data frame, And N is an integer greater than or equal to 1.

In a possible implementation manner, when the terminal and the satellite are far away from each other, the terminal calculates the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length, including: The terminal calculates the frame TA deviation according to the minimum TA deviation, the minimum transmission delay TA deviation, and the ratio of the TA update period to the data frame length:

The terminal performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation, including: the terminal selects the negative value of the absolute value of the minimum transmission delay TA deviation and (N-1) The frame TA deviation is subtracted by multiples, and TA compensation is performed on the TA of each frame of data in the TA update period, where N is the sequence number of the data frame, and N is an integer greater than or equal to 1.

In a possible implementation manner, the method further includes:

Acquiring, by the terminal, location information of the terminal;

Determining, by the terminal, the relative position of the terminal in the beam cell according to the position information and the position of the edge point of the beam cell;

The terminal performs linearization processing on the TA deviation between the two edge points of the beam cell, and obtains the first slope of the linear change of the TA deviation according to the TA deviation of the edge point of the beam cell, or according to the TA deviation of the beam cell The transmission delay TA deviation of the edge point obtains the second slope of the linear change of the transmission delay TA deviation;

Obtaining the TA deviation of the current position of the terminal according to the relative position of the terminal and the first slope, or obtaining the transmission delay TA deviation of the current position of the terminal according to the relative position of the terminal and the second slope;

The terminal performing TA compensation according to the TA update value and the TA compensation information includes:

When the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of the TA deviation of the current position of the terminal to perform TA compensation;

When the terminal and the satellite are far away from each other, the terminal subtracts the TA update value from the absolute value of the transmission delay TA deviation of the current position of the terminal to perform TA compensation.

In a possible implementation manner, the terminal receives the TA update value sent by the base station, which is the TA update value sent by the base station after compensation according to the current transmission delay TA deviation.

In the second aspect, the embodiments of the present application provide a method for updating timing advance, which may include:

The base station sends the timing advance TA update value and the beam cell number of the beam cell where the terminal is located to the terminal;

The base station receives the uplink data sent by the terminal using the TA value after TA compensation;

Wherein, the beam cell number corresponds to TA compensation information used by the terminal to perform TA compensation on the TA update value.

In a possible implementation manner, the TA compensation information includes TA compensation data or reference data used to calculate the TA compensation data;

The TA compensation data includes at least one of the following: the maximum TA deviation, the minimum TA deviation, the maximum transmission delay TA deviation, and the minimum transmission delay TA deviation of the current beam cell;

In the third aspect, an embodiment of the present application provides a terminal, which may include:

The transceiver unit is used to receive the TA update value sent by the base station and the beam cell number of the beam cell where the terminal is located;

A processing unit, configured to obtain corresponding TA compensation information according to the beam cell number, and perform TA compensation according to the TA update value and the TA compensation information in the TA update period;

The transceiver unit is also configured to use the TA value after TA compensation to send uplink data.

In a possible implementation manner, the reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the processing unit is specifically configured to:

Acquiring, according to the geocentric angle data and the satellite orbit height, the round-trip transmission delay change rate of the corresponding position of the geocentric angle data;

Obtain the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data; or

Obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, and the duration of the current TA update period;

In a possible implementation manner, the processing unit obtains the round-trip transmission delay change rate of the corresponding position of the geocentric angle data according to the geocentric angle data and the satellite orbit height, specifically according to the following formula:

In a possible implementation manner, the processing unit obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the geocentric angle data corresponding position, specifically according to the following The formula goes:

ΔTA _trans =T _a ′×t _trans ;

In a possible implementation manner, the processing unit obtains the TA according to the round-trip transmission delay change rate, the one-way transmission delay of the position corresponding to the satellite and the geocentric angle data, and the duration of the current TA update cycle. Deviation, specifically based on the following formula:

ΔTA=T _a ′×(t _trans +t _update );

In a possible implementation, the reference data includes satellite orbital height and Doppler frequency offset data of the current beam cell, and the processing unit is further configured to:

Obtaining the round-trip transmission delay change rate of the current position according to the Doppler data and the carrier frequency;

Obtain the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location; or

Obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period;

In a possible implementation manner, the processing unit obtains the round-trip transmission delay change rate of the current position according to the Doppler data and the carrier frequency, specifically according to the following formula:

In a possible implementation manner, the processing unit obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location, specifically according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

In a possible implementation manner, the processing unit obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

In a possible implementation manner, the processing unit is specifically configured to:

When the terminal and the satellite are close to each other, add the TA update value and the absolute value of any data in the TA compensation data to perform TA compensation;

When the terminal and the satellite are far away from each other, the TA update value is subtracted from the absolute value of any data in the TA compensation data to perform TA compensation.

When the terminal and the satellite are close to each other, adding the TA update value and the absolute value of the maximum TA deviation to perform TA compensation;

When the terminal and the satellite are far away from each other, the TA update value is subtracted from the absolute value of the minimum transmission delay TA deviation to perform TA compensation.

In a possible implementation manner, the TA compensation data further includes:

The processing unit is specifically used for:

Calculate the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length of the uplink data to be sent;

TA compensation is performed on the TA of each frame of data in the TA update period according to the frame TA deviation.

When the terminal and the satellite are close to each other, calculate the frame TA deviation according to the maximum TA deviation, the maximum transmission delay TA deviation, and the ratio of the TA update period to the data frame length of the uplink data to be sent;

The absolute value of the maximum transmission delay TA deviation is selected to be added to the N times the frame TA deviation, and TA compensation is performed on the TA of each frame of data in the TA update period, where N is the sequence number of the data frame, and N is An integer greater than or equal to 1.

When the terminal and the satellite are far away from each other, the frame TA deviation is calculated according to the minimum TA deviation, the minimum transmission delay TA deviation, and the ratio of the TA update period to the data frame length:

The negative value of the absolute value of the minimum transmission delay TA deviation is selected to subtract (N-1) times the frame TA deviation, and TA compensation is performed on the TA of each frame of data in the TA update period, where N is the data The sequence number of the frame, and N is an integer greater than or equal to 1.

In a possible implementation manner, the processing unit is further configured to:

Acquiring location information of the terminal;

Determine the relative position of the terminal in the beam cell according to the position information and the position of the edge point of the beam cell;

Linearize the TA deviation between the two edge points of the beam cell, obtain the first slope of the linear change of the TA deviation according to the TA deviation of the edge point of the beam cell, or obtain the first slope of the linear change of the TA deviation according to the edge point of the beam cell The transmission delay TA deviation obtains the second slope of the linear change of the transmission delay TA deviation;

When the processing unit performs TA compensation according to the TA update value and the TA compensation information, it is specifically configured to:

When the terminal and the satellite are close to each other, adding the TA update value and the absolute value of the TA deviation of the current position of the terminal to perform TA compensation;

When the terminal and the satellite are far away from each other, the TA update value is subtracted from the absolute value of the transmission delay TA deviation of the current position of the terminal to perform TA compensation.

In a fourth aspect, an embodiment of the present application provides a base station, which may include:

The sending unit is used to send the timing advance TA update value and the beam cell number of the beam cell where the terminal is located to the terminal;

A receiving unit, configured to receive uplink data sent by the terminal using the TA value after TA compensation;

The TA compensation data includes at least one of the following: a maximum TA deviation, a minimum TA deviation, a maximum transmission delay TA deviation, and a minimum transmission delay TA deviation of the current beam cell;

In a fifth aspect, a method is provided, which may include: receiving a TA value sent by a network device; acquiring a TA change rate; and communicating with the base station according to the TA change rate and the TA value.

In a possible implementation manner, the communicating with the base station according to the TA change rate and the TA value includes compensating the TA value according to the TA change rate; and communicating with the network according to the compensated TA value Device communication. It should be understood that the compensation here can also be referred to as update or adjustment, etc. The TA value is mainly increased or decreased according to the TA change rate to solve the communication problem caused by the untimely update of the TA value.

In a possible implementation manner, the acquiring the TA change rate includes one or more of the following methods: receiving one or more of the TA change rates; acquiring the TA according to the received TA change rate indication information The change rate, wherein the change rate indication information has a corresponding relationship with the TA change rate (it can be understood that the corresponding relationship also includes the corresponding relationship between the coverage area and the TA change rate indication information and/or the reference position and The corresponding relationship of the TA change rate indication information.); According to equivalent information, the TA change rate is obtained; or, the TA change rate stored in the terminal is obtained.

In a possible implementation manner, the acquisition of the TA change rate includes two methods, one of which acquires a part of the TA change rate, and the other method acquires the other part of the TA change rate. It can be understood that this implementation can be applied to a transparent transmission scenario. Among them, the TA change rate from the terminal to the satellite is obtained in one way, and the TA change rate from the satellite to the base station is obtained in another way.

In a possible implementation manner, the TA change rate includes one or more of the following: an offset of the TA change rate, a unit step-based scaling value of the TA change rate, or unit time The amount of change within TA. Wherein, the unit step or unit time may be pre-configured (for example, agreed in advance by a protocol), or may be received from the network device, of course, there may be other ways. The receiving from the network device includes receiving the unit step size or the unit time, or receiving the indication information of the unit step size or the unit time. It can be understood that the pre-configuration may also be configured to receive the unit step size or the unit time, or receive the unit step size indication information or the unit time indication information. The indication information of the unit step length has a corresponding relationship with the unit step; the indication information of the unit time has a corresponding relationship with the unit time.

In a possible implementation manner, obtaining the TA change rate according to equivalent information includes: selecting one of the TA change rates from one or more received TA change rates according to the equivalent information; or, According to the equivalent information, the TA change rate is calculated; wherein the equivalent information may be received by the network device, or may be directly obtained by the terminal.

In a possible implementation manner, the equivalent information includes one or more of the following: Doppler frequency offset, orbit height and elevation angle between the terminal and the network device, orbit height and the difference between the terminal and the network device The opening angle, or the height of the track and the geocentric angle between the terminal and the network device. It is understandable that all information that can calculate the TA change rate or select the TA change rate can be referred to as equivalent information. The above can only be an example of equivalent information, and it is not enough to be a restriction.

In a possible implementation manner, before compensating the TA value according to the TA change rate, the method further includes adjusting the TA change rate according to one or more received TA values. It can be understood that the terminal may continuously receive TA values periodically. If the terminal is connected to the network device for a period of time, it will receive multiple TA values, because the terminal can adjust the TA change rate according to the multiple TA values previously received. Generally, a large change among multiple TA values indicates that the terminal needs to adjust the TA change rate more.

In a possible implementation manner, the TA change rate includes one or more of the following: a common TA change rate, a specific TA change rate, the difference between the common change rate and the TA change rate, or twice The difference of the specific TA change rate; wherein, the public TA change rate may be the TA change rate of a reference location in the coverage area of the network device; the specific TA change rate may be the TA change of the location of the terminal rate. Among them, the common rate of change can be sent to one terminal in the coverage area, multiple terminals (the multiple terminals can be a group of terminals, for example, multiple terminals with close geographic locations or the same moving speed can be considered as one Group), or all terminals, this application does not limit this. In addition, it can be sent through broadcast information or not through broadcast information. The specific TA change rate can be sent to a terminal or a group of terminals (the grouping conditions can be similar to the above).

In a possible implementation manner, the coverage area includes one or more cells covered by the network device, the projection area of one or more beams of the network device on the ground, and one or more cells covered by the network device A part of an area of a cell, or a part of an area where a beam of the network device is projected on the ground. It is understandable that the coverage area can also be divided into other ways. Generally speaking, it should be a part or all of the coverage area of the network device.

In a possible implementation, the information sent by the network device (including but not limited to one or more of the following information, the TA change rate, the TA change rate indication information, the equivalent information, The unit step size, or the unit time) may send SIB, RRC, DCI, MIB, TAC, or PDSCH through one or more of the following information. It is understandable that if it is a PDSCH, it can also be divided into being sent in the PDSCH along with the downlink data or sent in a separately allocated PDSCH (it can be understood that the PDSCH does not send other information). Generally, this is mostly used to send a specific TA change rate.

In a possible implementation manner, the information sent by the aforementioned network device can be sent together with the TA value or sent separately, and the sending period can also be the same or different. It can be understood that if they are sent together, the sending cycle can be the same. If the sending period is different, the above information can be sent one or more times between the TA values sent twice, or the above information can be sent once between multiple TA values. If they are sent together, they can be in one message or not in one message.

In a possible implementation manner, the above information is sent in SIB, RRC, DCI, MIB, TAC, or PDSCH, which may be a newly added field in the information or an original field in the multiplexed information.

In a possible implementation manner, if it is a regenerative satellite scenario, the TA change rate may only be acquired during initial access, and the TA change rate is no longer needed to be acquired subsequently.

In a sixth aspect, a communication method is provided, including: a network device sends a TA value to one or more terminals; sending one or more of the following information, TA change rate, TA change rate indication information, equivalent information, Unit step size, or unit time;

Communicate with the terminal according to the TA value.

In a possible implementation manner, the TA change rate includes one or more of the following: an offset of the TA change rate, a unit step-based scaling value of the TA change rate, or unit time Intra TA change amount; wherein, the unit step size or unit time may be pre-configured, or may be sent by the network device; what is sent by the network device includes sending the unit step size or the unit time , Or send the indication information of the unit step length or the indication information of the unit time.

In a possible implementation manner, the change rate indication information has a corresponding relationship with the TA change rate, and the corresponding relationship further includes a corresponding relationship between a coverage area and the TA change rate indication information and/or a reference position Correspondence with the TA change rate indication information.

In a possible implementation manner, the equivalent information includes one or more of the following: Doppler frequency offset, orbit height and elevation angle between the terminal and the network device, orbit height and the terminal and the network device Or, the height of the track and the geocentric angle between the terminal and the network device.

In a possible implementation manner, the TA change rate includes one or more of the following: a public TA change rate, a specific TA change rate, or a difference between the common TA change rate and the TA change rate; wherein, The public TA change rate may be the TA change rate of a reference location in the coverage area of the network device; the specific TA change rate may be the TA change rate of the location where the terminal is located.

In a possible implementation manner, the coverage area includes one or more cells covered by the network device, the projection area of one or more beams of the network device on the ground, and one or more cells covered by the network device A part of an area of a cell, or a part of an area where a beam of the network device is projected on the ground.

In a possible implementation manner, the sending one or more of the following information includes sending through SIB, RRC, DCI, MIB, TAC, or PDSCH. The PDSCH can be sent together with other data in the PDSCH, or it can be sent separately in the PDSCH.

In a possible implementation manner, the sending one or more of the following information is not sent at the same time as the sending TA information, or the sending one or more of the following information and the sending TA information is sent at the same time; or, one or more of the following information is sent the same or different from the period of sending TA information.

In a seventh aspect, a device is provided. The device provided in this application has the function of realizing the behavior of the terminal or base station (or network device or satellite) in the above method, and it includes means for executing the steps or functions described in the above method. The steps or functions can be realized by software, or by hardware (such as a circuit), or by a combination of hardware and software.

In a possible design, the foregoing device includes one or more processors and communication units. The one or more processors are configured to support the apparatus to perform corresponding functions of the terminal and/or base station (or network equipment or satellite) in the above method. For example, the corresponding TA compensation information is obtained according to the beam cell number. The communication unit is used to support the device to communicate with other devices, and realize the receiving and/or sending functions. For example, receiving the TA update value and beam cell number sent by the base station.

Optionally, the device may further include one or more memories, where the memory is used for coupling with the processor and stores necessary program instructions and/or data for the device. The one or more memories may be integrated with the processor, or may be provided separately from the processor. This application is not limited.

The device may be a smart terminal or a wearable device, etc., and the communication unit may be a transceiver or a transceiver circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The device may also be a chip. The communication unit may be an input/output circuit or interface of a chip.

In another possible design, the above device includes a transceiver and a processor. The processor is used to run the computer program in the memory, so that the device executes the method described in any one or more of the first aspect to the sixth aspect. The memory can be arranged inside or outside the device.

In an eighth aspect, a system is provided, which includes the aforementioned terminal and base station. (Or including terminals, satellites and base stations; or including terminals and satellites)

In a ninth aspect, a computer-readable storage medium is provided for storing a computer program. The computer program includes a method for executing any one or more of the first to sixth aspects.

In a tenth aspect, a computer program product is provided. The computer program product includes: computer program code, which when the computer program code runs on a computer, causes the computer to execute any one of the first to sixth aspects above Or a multifaceted approach.

In an eleventh aspect, a device is provided for implementing any one or more of the methods in the first to sixth aspects.

In a twelfth aspect, an apparatus is provided, including a receiving unit, configured to receive a TA value sent by a network device; an acquiring unit, configured to acquire a TA change rate; The value communicates with the base station. (The transceiver unit can include a receiving unit and a sending unit, which can be set separately or combined)

In a possible implementation manner, the acquiring unit is specifically configured to compensate the TA value according to the TA change rate; the transceiving unit is specifically configured to communicate with the network device according to the compensated TA value.

In a possible implementation manner, the acquiring unit is specifically configured to receive one or more of the TA change rates; or, obtain the TA change rate according to the received TA change rate indication information, where: The change rate indication information has a corresponding relationship with the TA change rate; or, obtain the TA change rate according to equivalent information; or, obtain the TA change rate stored in the device. (The acquisition unit can sometimes be the same as the receiving unit)

In a possible implementation manner, the acquiring unit is specifically configured to acquire a part of the TA change rate in one method, and acquire another part of the TA change rate in another method. It can be understood that this can be applied to transparent transmission scenarios. Among them, the TA change rate from the terminal to the satellite is obtained in one way, and the TA change rate from the satellite to the base station is obtained in another way.

In a possible implementation manner, the acquiring unit is specifically configured to: select one TA change rate from one or more received TA change rates according to equivalent information; or, according to the equivalent information Information, calculate the TA change rate.

In a possible implementation manner, the receiving unit is further configured to, according to one or more TA values received; and the adjusting unit is configured to adjust the TA change rate.

In a possible implementation manner, the TA change rate includes one or more of the following: a public TA change rate, a specific TA change rate, or a difference between the common TA change rate and the TA change rate; wherein, The public TA change rate may be the TA change rate of a reference location in the coverage area of the network device; the specific TA change rate may be the TA change rate of the location where the terminal is located. Among them, the common rate of change can be sent to one terminal in the coverage area, multiple terminals (the multiple terminals can be a group of terminals, for example, multiple terminals with close geographic locations or the same moving speed can be considered as one Group), or all terminals, this application does not limit this. In addition, it can be sent through broadcast information or not through broadcast information. The specific TA change rate can be sent to a terminal or a group of terminals (the grouping conditions can be similar to the above).

In a thirteenth aspect, a device is provided, including: a sending unit, configured to send a TA value to one or more terminals; the sending unit is further configured to send one or more of the following information, the TA change rate , TA change rate indication information, equivalent information, unit step size, or unit time; the transceiver unit is used to communicate with the terminal according to the TA value. (The transceiver unit can include a receiving unit and a sending unit, and the two can be combined or set separately)

In a possible implementation manner, the sending unit is specifically configured to send information through SIB, RRC, DCI, MIB, TAC, or PDSCH. The PDSCH can be sent together with other data in the PDSCH, or it can be sent separately in the PDSCH.

In a possible implementation manner, one or more of the following information sent by the sending unit is not sent simultaneously with the sending of TA information, or one or more of the following information sent by the sending unit and The TA information is sent at the same time; or, one or more of the following information is the same as or different from the period of the TA information.

Through the above method, device, storage medium, program or chip, the device can compensate the received TA value according to the acquired TA compensation information, or according to its own TA change rate (or public TA change rate), to avoid TA deviation Inter-user interference and affect uplink decoding performance.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the following will describe the drawings that need to be used in the embodiments of the present application or the background art.

FIG. 1 is a schematic diagram of the architecture of a satellite communication system provided by an embodiment of this application;

2 is a schematic flowchart of a method for updating timing advance provided by an embodiment of the application;

FIG. 3 is a schematic diagram of changes in the maximum TA deviation and the transmission delay TA deviation provided by an embodiment of the application;

4 is a schematic flowchart of another method for updating timing advance provided by an embodiment of this application;

FIG. 5 is a schematic flowchart of another method for updating timing advance provided by an embodiment of this application;

FIG. 6 is a schematic diagram of the composition of a terminal provided by an embodiment of the application;

FIG. 7 is a schematic diagram of the composition of another terminal provided by an embodiment of the application;

FIG. 8 is a schematic diagram of the composition of a base station provided by an embodiment of the application;

FIG. 9 is a schematic diagram of the composition of another base station provided by an embodiment of the application;

FIG. 10 is a flowchart of another method provided by an embodiment of this application;

FIG. 11 is a flowchart of another method provided by an embodiment of the application;

FIG. 12 is a flowchart of another method provided by an embodiment of this application;

FIG. 13 is a flowchart of another method provided by an embodiment of this application;

14 is a schematic diagram of the geometric relationship between a satellite and a ground station (base station) provided by an embodiment of the application;

FIG. 15 is a schematic structural diagram of another satellite communication system provided by an embodiment of this application.

detailed description

The embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

The terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes unlisted steps or units, or optionally also includes Other steps or units inherent to these processes, methods, products or equipment.

The terminal referred to in the technical solutions of the embodiments of the present application may be a device with communication function, and may include a handheld device with wireless communication function, a vehicle-mounted device, a wearable device, a computing device or other processing connected to a wireless modem Equipment etc. In different networks, terminals can be called different names, such as: access terminal, user equipment (UE), user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile equipment, user terminal , Terminals, wireless communication devices, user agents or user devices, handheld devices with wireless communication functions, computing devices or other processing devices connected to wireless modems, in-vehicle devices, wearable devices, and terminal devices in the future 5G network. Terminal equipment can communicate with one or more core networks via a radio access network (RAN), or can access distributed networks through self-organization or authorization-free methods, and terminal equipment can also access through other methods The wireless network communicates, and the terminal device can also directly communicate wirelessly with other terminal devices, which is not limited in the embodiment of the present application.

The base station (also referred to as network equipment or ground station) referred to in the embodiments of the present application may be a type of equipment deployed on a wireless access network to provide wireless communication functions. The name of the base station may be different in different wireless access systems. For example, in the Universal Mobile Telecommunications System (UMTS) network, the base station is called NodeB (NodeB), and the base station in the LTE network is called NodeB. It is an evolved NodeB (evolved NodeB, eNB or eNodeB), and the base station in the new radio (NR) network is called the transmission reception point (TRP) or the next generation node B (gNB), Or in other networks where multiple technologies are converged, or in other evolutionary networks, base stations may also use other names. The present invention is not limited to this. In this application, the base station can be deployed on the satellite or in the ground station.

The satellite referred to in the embodiments of this application refers to a device that orbits a planet and periodically orbits in a closed orbit. According to the satellite's orbital height, satellites can be divided into geostationary earth orbit (GEO) satellites, medium earth orbit (MEO) satellites and low earth orbit (LEO) satellites. The satellite may be equipped with on-board data processing capabilities due to the deployment of network equipment, or it may be equipped with equipment that can only perform spectrum shifting of the received data and forward the data to the network equipment deployed on the ground for processing.

The compensation in the embodiments of the present application may also be referred to as adjustment, including adjustment of larger, smaller, etc., which is not limited in this application.

The instructions in the embodiments of the present application may include direct instructions and indirect instructions. Direct instructions can be sent directly or inform the information that needs instructions. Indirect instructions can be sending other information, which can indirectly indicate the information that needs to be obtained, or the information originally indicates other information, but other information can also be indicated in this application, or the required information can be obtained after calculation based on the indicated information information.

The TA value in the embodiment of the present application refers to an offset between the start time of the downlink subframe received by the terminal and the start time of the uplink subframe sent by the terminal. The network equipment can control the time deviation of the uplink signals from different terminals to the network equipment within the allowable error range by indicating a dedicated TA value to each terminal, thereby avoiding interference between signals of different terminals in the cell.

The TA change rate in the embodiments of the present application refers to the speed at which the TA value changes over time, and describes the speed at which the TA value changes. It should be understood that the TA change rate mentioned in this application not only includes the TA change rate itself, but also the offset of the TA change rate, and the offset may be for the TA change rate (or TA deviation) previously received. The offset of the shift amount) can also be the offset for other values. This saves the number of bits sent.

The equivalent information in the embodiment of the present application may be a parameter or variable that can be derived and converted from each other through a theoretical formula and the TA change rate. Generally, the information that can be converted to the rate of change of TA includes Doppler frequency offset information, including the combination of angles such as elevation angle, opening angle, and geocentric angle between the terminal and the satellite and the orbit height. Here is only a simple example of equivalent information, and the equivalent information is not limited to the above information.

In the embodiment of the present application, the unit step length may be a certain unit length as a quantization unit. It can be understood that the unit step size is a kind of scaling, and its use can achieve the effect of saving transmitted bits. For example, the unit of TA change rate is us/s, and 2 us/s (ie 2us/s) is used as the unit step size. Indication +2 means TA change rate +4us/s, and indication -3 means TA change rate -6us/s. For another example, the minimum sampling time length used in the existing protocol is Tc, and 16·64 Tc is used as the unit step size. The network device indicates that the TA value can be quantified by the above step size. If the network device indicates that the TA value is equal to 6, It means that the actual TA adjustment is 6·(16·64·Tc). Here, there are no restrictions on the unit and length used in the unit step definition.

In the embodiment of the present application, the unit time may be a certain length of time as a quantitative unit. For example, the unit time can be the length of the existing time unit (such as 1ms, 1s, etc.), it can be a fixed length (such as 2s, 10s) of the appointed time, or the specified timer timeout time (such as uplink A configurable timeout period of the time alignment timer (500ms), etc. Here, there are no restrictions on the unit and length used in the unit step definition.

Please refer to FIG. 1, which is a schematic diagram of the architecture of a satellite communication system provided by an embodiment of this application. Under the architecture shown in FIG. 1, a satellite 10, a base station 20 (the base station 20 is integrated on the satellite 10 in FIG. 1), and a terminal 30 And other composition.

Among them, the satellite 10 is located in space, and it can communicate with the ground station and the terminal 30.

The base station 20 can be integrated with the satellite 10, and the function of the base station 20 is realized by the satellite. This communication system scenario can be called a regenerated satellite scenario (as shown in FIG. 1).

The base station 20 and the satellite 10 can also be independently arranged in a communication system, and they can send data to the terminal 30 through the satellite 10, or can independently send control signaling and data to the terminal 30. For example, the base station 20 may periodically send the TA update value to the terminal 30 so that the terminal 30 can process the uplink data according to the received TA update value. The beam cell can also be divided into beam cell numbers, and then the beam cell number can be sent to the terminal 30 so that the terminal 30 knows which beam cell it is in, and updates the received TA according to the TA compensation information corresponding to the beam cell number Value for compensation. For another example, if the base station 20 is on a ground station, uplink communication may include two parts: terminal 30 to satellite 10, satellite 10 to base station 20, and downlink communication also includes two parts, base station 20 to satellite 10, and satellite 10 to terminal 30. The one between the base station and the satellite can be called the feeder link, and the one between the satellite and the terminal can be called the user link. In this example, the satellite 10 has no processing capability, or the processing capability is relatively weak, and the assistance of the base station 20 is required. This communication scenario can be called a transparent satellite scenario (as shown in Figure 15).

It should be understood that when the base station 20 and the satellite 10 are installed separately, the method performed by the base station 20 in this application can be performed by the satellite 10 independently or the satellite 10 and the base station 20 can be performed together; the method performed by the satellite 10 in this application can also be performed independently. It is executed independently by the base station 20 or executed by the satellite 10 and the base station 20 together, which is not limited in this application.

In the communication system, the TA value is usually updated according to a certain period, and the update period can be 2 Hz. The update frequency of the TA value can also be sending a TA update command (carrying the TA value) once within 500 ms. For example, a network device issues a TA value with an integer multiple of 16·64/2 ^μ ·T _c as the adjustment granularity to the terminal (also called a TA adjustment command, which carries the TA value. The terminal receives the TA value (which can only be based on TA value can also be updated according to TA value and other indications (or called TA adjustment), where Tc=1/(480·103·4096)=0.509×10 ^-6 ms can be the length of time The unit, μ may refer to the index of the subcarrier width. TA adjustment commands have the following two forms:

During initial access, a TA adjustment command of x ₁ bits is used, and this value indicates the index of the amount of time the terminal needs to adjust. After receiving the command, the terminal will adjust the uplink transmission timing, and the adjustment at this time is performed relative to the terminal's downlink timing. This allows the network device to set the timing advance in the range of 0 to the maximum value of TA with a step size of 16·64/2 ^μ times T _c .

After the initial access has achieved uplink synchronization, the TA value of the terminal needs to be continuously updated to cope with changes in the transmission time for the channel to reach the network device caused by changes in the location of the terminal and the network equipment or changes in the channel environment. The TA update process may be to issue an x ² bit TA update command (which may be similar to the TA adjustment command) through the network device to instruct the terminal to adjust its new transmission timing based on the original uplink transmission timing. The update command also takes 16·64/2 ^μ times T _c as the step size, and adjusts the TA value within the range specified in the agreement. The update value of TA can be positive or negative. A positive value indicates that the transmission delay between the terminal and the network device becomes larger, and a negative value indicates that the transmission delay between the terminal and the network device becomes smaller.

In addition, in the communication system, the TA deviation includes not only the transmission delay TA deviation, but also the update cycle TA deviation, because the transmission delay of the signal from the satellite to the terminal is long. When the terminal receives the TA issued by the satellite, the current time There has been a transmission delay TA deviation between the actual TA value and the TA value received by the terminal; and in the TA update period, as time progresses, the actual TA value at the current moment will be updated relative to the TA value received by the terminal. The periodic TA deviation causes a greater deviation between the actual TA value and the terminal received TA value.

The terminal 30 can perform data communication with the satellite 10 or the base station 20, can receive control signaling and downlink data sent by the satellite 10 or the base station 20, and can also send uplink data to the satellite 10 or the base station 20 to complete the transmission of various service data. By receiving the TA update value and beam cell number sent by the base station 20, the terminal 30 can obtain TA compensation information to compensate the TA update value, thereby reducing the deviation between the TA update value and the actual TA, and avoiding different terminals due to TA deviation The inter-interference and the impact on the decoding performance will improve the communication performance of the satellite communication system.

As shown in any one or more of Figures 10-13, optionally, the network device receives the uplink reference signal sent by the terminal (1001). For example, uplink random access preamble, SRS, DMRS, PUCCH and other signals. Obtain the TA value of the corresponding terminal according to the uplink reference signal network device. The network device sends the TA value (periodically) to the terminal (1002 or 1300)). The terminal receives the TA value (1001 or 1301) issued by the network device. The terminal obtains the TA change rate or its equivalent information indicated by the network device (1102), or estimates the TA change rate by itself. Before receiving the new TA value, compensate the received network device to issue the TA value (1004, 1104, or 1302).

In a possible implementation manner, the terminal compensates the received TA value according to the common rate of change indicated by the network device (including direct indication and indirect indication) and the received TA value. Communicate with network equipment according to the compensated TA value.

In a possible implementation manner, the terminal adjusts the public change rate according to the public change rate and the received TA value indicated by the network device (including direct and indirect instructions), and compensates the received TA value according to the adjusted public change rate. Communicate with network equipment according to the compensated TA value.

In another possible implementation manner, the terminal compensates the received TA value according to the TA value indicated by the network device and the change rate of the terminal. Communicate with network equipment according to the compensated TA value.

In the embodiments of the present application, for convenience and consistency of description, the base station 20 is generally integrated on the satellite 10 as an example for description. When the base station 20 is located in a communication system, the forwarding process of the satellite 10 can be added. Generally, the remaining processes are similar. . It is understandable that the rest of the processes can also be different. The following examples can illustrate different scenarios.

The method for updating the timing advance of this application will be described in detail below in conjunction with Figures 2 to 14.

Please refer to FIG. 2. FIG. 2 is a schematic flowchart of a method for updating timing advance according to an embodiment of the application; specifically, it includes the following steps:

S201. The terminal receives the timing advance TA update value and the beam cell number of the beam cell where the terminal is located from the base station.

Optionally, the base station may update the value of TA in a certain period by using other signals such as random access preamble, sounding reference signal (Sounding Reference Signal, SRS), and send the TA update command to the terminal. The terminal receives the TA update value sent by the base station in the same cycle.

Optionally, the base station can send radio resource control protocol (Radio Resource Control, RRC for short), System Information Block (System Information Block, SIB for short), Downlink Control Information (DCI), and master system module (master Information block, MIB for short) or other signaling sends the beam cell number. Alternatively, the base station may also construct information signaling to send the TA update value and/or the beam cell number, which is not limited in the embodiment of the present application.

Among them, before sending the beam cell number, the base station can divide the overhead period of the satellite into multiple regions according to a certain parameter, such as angle, time, or projection size corresponding to the ground. Each region has a unique number and its own TA. Pre-compensation value. Each area can be a cell. Generally speaking, the range of a satellite cell usually corresponds to the projection of a satellite beam on the ground; each area can also contain multiple satellite beams or multiple cells, or only contain the satellite beams. Part of the area. In the new radio access technology (NR), different beamlets may exist in the same cell. For example, a synchronization signal block (Synchronization Signal Block, SSB) corresponds to different beams in a cell. These beams can be Designed to show a certain angle or geographic area distribution from the ground, these beam sets can also be used as divided areas. In addition, there may be dedicated tracking beams for one or a group of terminals, and these tracking beams for a cell may also be used as divided areas.

For example, the range of the geocentric angle during the satellite overhead period can be used as an example to divide the intervals, and set a unique number for each interval as the beam cell number, which can be used for terminals or other devices to distinguish and identify beam cells, beam cell numbers It may also be referred to as the number of the beam cell, the identifier of the beam cell, etc., which is not limited in the embodiment of the present application.

S202. The terminal obtains corresponding TA compensation information according to the beam cell number.

Among them, the beam cell number and TA compensation information are bound together. The TA compensation information can be sent by the base station to the terminal together with the beam cell number through the aforementioned signaling, or can be sent separately. Alternatively, when the angles of all beam cells are unchanged, the TA compensation information can also be stored as local information on the terminal side, which is also not limited in the embodiment of the present application.

In the embodiment of the present application, for the convenience of description, a low-orbit satellite communication system with a satellite orbit of 700 km, a terminal minimum elevation angle of 10 degrees, and a TA update cycle of 80 ms will be used as an example for description. Here, the range of the geocentric angle during the satellite overhead is taken as an example to divide the interval. Suppose the beam cell radius of the satellite communication system is 100km, corresponding to the geocentric angle:

θ=l/R=0.03136rad=1.796°

Among them, l represents the diameter of the beam cell, and R represents the radius of the earth.

The range of the geocentric angle during the satellite overhead is [-17.45°,17.45°], so at least it needs to be divided into

Intervals. Let the number of divided beam cells be M=20, and each beam cell corresponds to different TA compensation information.

Since the TA deviation is composed of the transmission delay TA deviation and the update period TA deviation, the TA compensation information can be composed of two parts ΔTA _update and ΔTA _trans or other reference data that can calculate the two TA compensation data. When the terminal is located in the beam cell, the TA deviation of the terminal is the sum of the transmission delay TA deviation and the update period TA deviation, and the update period TA deviation is the round-trip transmission delay change rate of the current location and the current The product of the duration of the TA update cycle. These TA compensation information can be issued by the base station, and there can be multiple indications and representation methods. For example, the TA deviation compensation information (unit: TA step size) of each beam cell can be as shown in the following table:

It is assumed that the terminal sequentially goes through beam cells 1-20 during the satellite overhead period. Among them, the TA compensation data of beam cells 1-10 and 11-20 are symmetric with the sub-satellite point as the center.

As shown in the above table, the base station issues

As TA compensation information for each beam cell. among them,

Indicates the absolute value of the maximum deviation between the received TA update value and the actual TA when the terminal in a certain beam cell just receives the TA update value issued by the base station, that is, the maximum transmission delay TA deviation,

Indicates the absolute value of the minimum deviation between the received TA update value and the actual TA when the terminal in a certain beam cell just receives the TA update value issued by the base station, that is, the minimum transmission delay TA deviation; |ΔTA _max | Before the terminal in the beam cell receives the next TA update value issued by the base station, the absolute value of the maximum deviation between the received TA update value and the actual TA, |ΔTA _min | means that the terminal in a beam cell receives the next TA update value issued by the base station Before a TA update value, receive the absolute value of the minimum deviation between the TA update value and the actual TA.

Optionally, in addition to these TA compensation information, the base station can also send the following information bound to the beam cell number

or

As TA compensation information. Among them, ΔTA _trans ′ represents the change rate of TA deviation caused by the transmission delay TA deviation in the beam cell, and ΔTA′ represents the change rate of TA deviation caused by the transmission delay TA deviation and the update period TA error in the beam cell.

Optionally, the base station may also send the following reference data for calculating the aforementioned TA compensation data. The reference data may include satellite orbital height and geocentric angle data of the current beam cell, and the geocentric angle data includes the maximum geocentricity. Angle and minimum geocentric angle;

Or the reference data may include: Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset.

In the description of the calculation process below, h is used to represent the satellite orbital height, {θ _max , θ _min } represent the maximum geocentric angle and minimum geocentric angle of the beam cell, respectively,

Respectively represent the absolute value of the maximum Doppler frequency deviation and the absolute value of the minimum Doppler frequency deviation of the beam cell.

The terminal may obtain the round-trip transmission delay change rate of the corresponding position of the geocentric angle data according to the geocentric angle data and the satellite orbit height;

Specifically according to the following formula:

Then the terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data; specifically, it can be performed according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

Or the terminal may also obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, and the TA update period;

Specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

Wherein, the transmission delay TA deviation obtained by the terminal according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the terminal according to the minimum geocentric angle in the geocentric angle data The acquired transmission delay TA deviation is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is the minimum transmission delay TA deviation and the minimum update The sum of period TA deviations.

Alternatively, the terminal may obtain the round-trip transmission delay change rate of the current position according to the Doppler data and the carrier frequency; specifically according to the following formula:

Then the terminal can obtain the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location; specifically, it is performed according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

Alternatively, the terminal may also obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay at the current location, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

It should be noted that the above calculations are based on the geocentric angle data as an example, or it can also be calculated using the half opening angle or the user elevation angle, and the geocentric angle, half opening angle, and user elevation angle data can be calculated by mutual conversion. In addition, the geocentric angle data and Doppler frequency offset data can also be converted and calculated according to the following formula.

Among them, f _c represents the carrier frequency, f _d represents the Doppler frequency deviation of the current position, c represents the speed of light, ω represents the relative angular velocity between the satellite and the user, R represents the radius of the earth, h represents the satellite orbit height, and θ represents the geocentric angle data.

Of course, the above TA compensation information can also be stored on the terminal side. The base station issues a beam cell number such as 11, and the terminal can query and obtain TA compensation data. Alternatively, some terminals with positioning capabilities can also obtain the above parameter data themselves to calculate TA compensation data. The embodiments of this application do not make any limitation. When the terminal changes cells, the TA compensation information can be acquired again. The base station can send multiple data to the terminal, and the terminal can select one or more of the data for compensation as needed when making compensation. In addition, various data in the TA compensation information sent by the base station can be absolute values, which can be used directly by the terminal, or non-absolute data can also be sent, which are processed by the terminal and used, and this embodiment of the application does not make any limitation.

S203. In the TA update period, the terminal performs TA compensation according to the TA update value and the TA compensation information.

After the terminal obtains the TA compensation information, it can perform TA compensation on the received TA update value according to the TA compensation information.

When the terminal is located in the beam cell, the TA deviation of the terminal is the sum of the transmission delay TA deviation and the update period TA deviation, and the update period TA deviation is the round-trip transmission delay change rate of the current location and the current The product of the duration of the TA update cycle. That is, the TA deviation ΔTA between the actual TA between the satellite and the terminal and the TA received by the terminal is composed of the transmission delay TA error ΔTA _trans and the update period TA error ΔTA _update . For a terminal in a certain position in the beam cell, when the terminal just obtains the TA update value issued by the base station, ΔTA = ΔTA _trans ; from the moment the terminal just receives the TA value issued by the satellite to the moment when the terminal is about to receive the TA update value from the base station The moment when the next TA update value is sent, that is, during the current TA update cycle, ΔTA _update gradually increases from 0 to

At the critical moment when the terminal is about to receive the next TA update value issued by the base station, if the terminal continues to use the TA update value recently issued by the base station, there will be a maximum TA deviation between the actual TA value and the received TA update value

Please also refer to FIG. 3, which is a schematic diagram of the variation of the maximum TA deviation and the transmission delay TA deviation provided by the embodiment of this application, as shown in FIG. 3, where the abscissa is the geocentric angle θ, and the ordinate is the TA deviation. The straight line composed of small dots and short line segments is the graph formed by the variation of the transmission delay TA deviation with the geocentric angle, and the solid curve is the graph formed by the maximum TA deviation of the corresponding position of the geocentric angle with the geocentric angle. For a certain geocentric angle, The maximum TA deviation is the sum of the transmission delay TA deviation determined by the position and the maximum update period TA deviation of the position. The straight line composed of small points is the expected compensation target limit. When the geocentric angle changes from -0.3 to 0, when the terminal first sees the satellite, there is the maximum negative TA deviation and the maximum negative transmission delay TA deviation; as the satellite approaches the terminal, the TA deviation gradually decreases, and the transmission time The delay TA deviation also gradually decreases. After the satellite passes the top, the TA deviation is positive and gradually increases, and the transmission delay TA deviation is also positive and gradually increases. It can be seen that there may be a certain regularity in the change of TA deviation. Therefore, the terminal can compensate for TA deviation according to these rules. The principle of TA deviation pre-compensation may be: in order to prevent the uplink data from causing inter-symbol interference, the TA value after autonomous compensation of the terminal does not exceed the short CP range specified by the frame structure, and is a positive TA value that is as close to the actual value as possible.

Therefore, based on the above compensation principle, the terminal can use the ΔTA _trans and ΔTA information bound to the beam cell number to compensate for the TA update value issued by the base station within the two TA update intervals. When the terminal and the satellite are close to each other, you can select |ΔTA _max | or the value of |ΔTA _max | calculated by reference data as the uniform TA deviation compensation value of the beam cell; when the terminal and the satellite are far away from each other, you can choose

Or the negative value of |ΔTA _min | calculated with reference data is used as the uniform TA offset compensation value in the beam cell.

S204: The terminal uses the TA value after TA compensation to send uplink data.

When the TA update period is reached, the terminal can again receive the new TA update value sent by the base station according to the TA update period.

In this embodiment, the terminal receives the TA update value and the beam cell number sent by the base station, and obtains the TA compensation information according to the beam cell number, so that the TA update value can be self-compensated during the TA update period, which improves TA The update frequency reduces the impact on the uplink data reception performance caused by the rapid change of TA in the satellite communication system, such as inter-user interference caused by TA deviation and the impact on decoding performance. It avoids the current limitation that the base station cannot frequently send TA update information to the terminal due to the limitation of resources and overhead. At the same time, it further avoids the influence of the update cycle TA deviation generated in the TA update cycle, and improves the working performance of the satellite communication system And efficiency.

Please refer to FIG. 4, which is a schematic flowchart of another method for updating timing advance provided by an embodiment of this application; in this embodiment, time granularity is used to distinguish, and the uplink data sent in the beam cell is classified according to different data. The frames are respectively subjected to TA compensation to improve compensation accuracy. At this time, the TA compensation data obtained by the terminal includes the maximum TA deviation, the minimum TA deviation, the maximum transmission delay TA deviation, and the minimum transmission delay TA deviation of the current beam cell. Steps S401-S402 are the same as steps S201-S202, and the method further includes:

S403. The terminal calculates the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length of the uplink data to be sent.

S404. The terminal separately performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation.

During the period when the terminal has just received the issued TA update value and the terminal is receiving the next TA update value issued by the base station, the TA deviation value changes from ΔTA _trans to ΔTA. During this period, the rate of change of the round-trip transmission delay is almost unchanged, and it can be considered that the change from ΔTA _trans to ΔTA within the update period can be linear. Therefore, the TA update period can be divided into smaller time granularity, and the terminal uses the divided time granularity as a unit to independently compensate the TA update value issued by the base station. For example, the period for the base station to update the TA is 10*N milliseconds, and the terminal can update the TA used for autonomous compensation with a data frame length of 10 milliseconds as a time interval.

When the terminal and the satellite are close to each other, the terminal can calculate the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length, which can specifically include: the terminal according to the maximum TA deviation and maximum transmission Time delay TA deviation, and the ratio of the TA update period to the data frame length to calculate the frame TA deviation: let

As the frame TA deviation of each frame. The terminal has just received the first frame data selection of the TA update value issued

As the deviation compensation value, the data selection of the second frame received the TA update value

As the deviation compensation value,..., the data selection of the Nth frame before receiving the next TA update value

As the deviation compensation value. N is the serial number of the data frame, and N is an integer greater than or equal to 1.

When the terminal and the satellite are far away from each other, the terminal may calculate the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length, which may specifically include: the terminal according to the minimum TA deviation, The minimum transmission delay TA deviation, and the ratio of the TA update period to the length of the data frame of the uplink data to be sent to calculate the frame TA deviation: let

As the frame TA deviation of each frame. The first frame data selection after the terminal has just received the TA update value

As the deviation compensation value, the second frame data selection after receiving the TA update value

It should be noted that the TA compensation data described above can also be obtained by calculation using the reference data in the embodiment shown in FIG. 2, which will not be repeated here.

In the embodiment of the present application, the terminal autonomously compensates the TA update value issued by the base station with a smaller time granularity within the TA update cycle, which can improve the accuracy of TA compensation and further reduce the difference between the terminal's use of TA and the actual TA. Deviation, to avoid interference between users caused by TA deviation and the impact on decoding performance.

Please refer to FIG. 5, which is a schematic flowchart of another method for updating timing advance provided by an embodiment of this application; in this embodiment, the terminal may further perform refined TA compensation according to the location information of the terminal. Wherein, steps S501-S502 are the same as steps S401-S402, and after S502, the following steps are further included:

S503. The terminal obtains location information of the terminal.

Optionally, the terminal may obtain its own location information through Doppler frequency offset measurement or other positioning methods.

S504. The terminal determines the relative position of the terminal in the beam cell according to the position information and the position of the edge point of the beam cell.

After the beam cell is determined according to the beam cell number, the position of the edge point of the beam cell can be obtained. Then, the relative position of the terminal in the beam cell can be obtained by combining the position information of the terminal.

S505. The terminal linearizes the TA deviation between the two edge points of the beam cell, and obtains the first slope of the linear change of the TA deviation according to the TA deviation of the edge point of the beam cell, or according to the beam The transmission delay TA deviation of the edge point of the cell obtains the second slope of the linear change of the transmission delay TA deviation.

After the terminal obtains the TA compensation data in the TA compensation information according to the beam cell number, it can obtain the TA deviation of the edge point and the transmission delay TA deviation. Then, according to the parameters of the two extreme points, the first slope of the linear change of the TA deviation or the second slope of the linear change of the transmission delay TA deviation to be obtained can be obtained.

S506. Obtain the TA deviation of the current position of the terminal according to the relative position of the terminal and the first slope, or obtain the transmission delay TA deviation of the current position of the terminal according to the relative position of the terminal and the second slope.

Combining the relative position of the terminal and the edge point and the obtained first slope or second slope, the TA deviation and the transmission delay TA deviation of the current position of the terminal can be mapped, and a more accurate TA corresponding to the current position of the terminal can be obtained. Compensation information.

S507. The terminal performs TA compensation according to the TA update value and TA compensation information corresponding to the current location of the terminal.

Optionally, when the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of the TA deviation of the current position of the terminal to perform TA compensation;

Optionally, in order to save signaling overhead, the edge cell with a small TA deviation can only transmit

or

Or their mean value. For the method of sending reference data, you can send only {h,θ _max } or {h,θ _min } or {h,(θ _max +θ _min )/2}, or

or

The TA deviation of the beam cell close to the sub-satellite point changes much faster than that of the edge cell, and the base station can send {|ΔTA _max |,|ΔTA _min |,

Or its equivalent {h,θ _max ,θ _min } or

The information is given to the terminal, and the terminal can use Doppler measurement or other methods to estimate its position. The Doppler change rate of these beam cells is large and the Signal to Noise Ratio (SNR) is high, and the estimation of the position information is relatively accurate.

In the embodiment of this application, the terminal first obtains its own position information in the beam cell during the TA update period, and uses the position information and known TA compensation information to obtain a more refined TA compensation corresponding to the current position Data, and then autonomously compensate the TA update value issued by the base station, which can further improve the accuracy of TA compensation, reduce the deviation between the terminal's use of TA and the actual TA, and avoid the interference between users caused by the TA deviation and the impact on decoding performance.

It should be noted that in the embodiment of the present application, the terminal may also combine the method described in FIG. 4 to divide the change from |ΔTA _trans | to |ΔTA| in time within the update period, and calculate the real-time TA deviation compensation value , To further improve the accuracy of TA deviation compensation.

In addition, for the TA update value sent by the base station, since the base station can obtain the accurate TA of the terminal at the current moment, the round-trip transmission delay change rate, and the relative motion mode of the terminal close or far away, the base station can calculate the current ΔTA _trans , And after compensating for the deviation caused by the transmission delay, the TA update value is issued. That is, the TA update value sent by the base station may be the TA update value sent by the base station after compensation according to the transmission delay TA deviation at the current moment. Since the base station has pre-compensated the sent TA update value, the deviation between the terminal's received TA and the actual TA in the TA update period will change from 0 to |ΔTA|-|ΔTA _trans |. At this time, the TA update value can be combined with the method in the embodiment shown in FIGS. 2 to 5, which can further improve the accuracy of the terminal to compensate for the TA deviation in the TA update period.

This embodiment of the application provides a terminal that estimates its own rate of change based on the public rate of change indicated by the network device and the received TA value during the TA update period, and uses the estimated value of its own rate of change to compensate for the received TA value .

The network device instructs the TA change rate of a reference location in the coverage area as a uniformly configured public TA change rate in the area, and delivers it to all terminals or a group of terminals in the coverage area. During the initial access period, the terminal uses the public TA change rate to compensate the TA value received last time within the period when the network device issues the TA update value. Optionally, the subsequent terminal adjusts the common TA change rate according to the TA values received from multiple TA commands to obtain the TA change rate used for actual compensation. Use the TA change rate to compensate the TA value.

Optionally, the coverage area refers to multiple coverage areas obtained by dividing the entire coverage area of the network device according to a certain parameter (such as angle, time, or projection size corresponding to the ground), and each coverage area may be a cell. For example, generally speaking, the range of a satellite cell usually corresponds to the projection of a satellite beam on the ground; each coverage area may also include multiple satellite beams or multiple cells, or only a part of a satellite beam. Each coverage area can also correspond to one or a group of terminals.

In the embodiment of this application, the common TA change rate may be one or more. If it is one, the common TA change rate corresponds to the change rate of a certain reference location in the coverage area. If there are multiple, then the multiple Each public TA change rate corresponds to the change rate of different reference positions in the coverage area. It should be understood that the TA change rate is variable and can be dynamically adjusted by the network device. It should be understood that the common TA change rate in the embodiment of the present application may also be an offset of the corresponding reference position change rate. It should be understood that, as the common TA change rate of the current coverage area, the reference location may be the center point of the coverage area, the edge point of the coverage area, or other designated locations, which is not limited in this application.

Optionally, because the TA change rate is a Doppler frequency offset, or a value related to angle information such as the elevation angle, the opening angle, and the geocentric angle of the terminal and the satellite. When there are multiple public TA change rates received by the terminal, the terminal can also select the corresponding public TA change rate according to information such as Doppler frequency offset and relative angle measured by the network device or by the terminal.

It can be understood that the TA change rate in the embodiments of the present application may be the TA change rate. Or it can also be the value of the TA change rate multiplied by a certain unit step (or called a scaling factor) (for example, half of the TA change rate may represent the user downlink timing change rate). Or it is equivalent information that can be converted to the rate of change of TA (for example, Doppler frequency offset, or angle information including the elevation angle, opening angle, and geocentric angle of the terminal and the satellite). It should be understood that the equivalent information here may be indicated by the network device, or measured by the terminal itself, or may also be the TA change amount converted based on the TA change rate per unit time. Wherein, the unit time of the TA change amount may be a value agreed in advance between the network side and the terminal (for example, a protocol stipulation), or directly indicated by the network device, or indirectly indicated by the network device. For example, the timeout time of the uplink time alignment timer (timeAlignmentTimer) is used as the unit time. For another example, it is based on the unit schedule agreed by the network and the terminal as shown in Table 1. The network device sends instruction information (index) based on the generated table.

指示信息Instructions	单位时间长度 Unit time length
00	t0t0
11	t1t1
……	……
nn	tntn

Table 1

It can be understood that the unit time in the embodiments of the present application can be a unified configuration in the unit of a network device, or can be an independent configuration of a single or multiple coverage areas, or a designated configuration of one or a group of terminals; the unit time can be The indication is bundled with the rate of change of TA, or independently.

In the embodiment of this application, the public TA change rate or other information is issued in one or more forms of SIB/RRC/DCI/MIB. Optionally, the public rate of change can be sent together with the TA value or developed separately. The sending cycle of the TA value can also be the same or different.

For example, the public TA change rate will be indicated in the broadcast information. The following is an example of how the public TA change rate is indicated in SIB1:

It can be understood that in this embodiment of the present application, the TA change rate may be in the form of newly added fields, or the original fields may be reused.

The TA change rate in the embodiment of the present application may be directly indicated by the network device, or may be indicated by indication information, which has a corresponding relationship with the TA change rate. For example, as shown in Table 2

指示信息(索引)Instructions (index)	TA变化率 TA change rate
00	CommonRate0CommonRate0
11	CommonRate1CommonRate1
……	……
nn	CommonRatenCommonRaten

Table 2

It should be understood that Table 2 is only an example, and the relationship between the indication information and the T variable can also be presented in other ways, which is not limited in this application. Optionally, the indication information may also correspond to the coverage area (for example, the serial number corresponding to the coverage area). Optionally, it may also correspond to a certain reference position of each coverage area. At this time, the TA change rate may be the change rate of a certain reference position or its offset. For example, as shown in Table 3,

table 3

It can be understood that the foregoing form may be an agreed form (for example, agreement agreement), or may be issued by a network device.

Optionally, the indication information may be combined with the unit step length when indicating the TA change rate or the offset. At this time, the indication information has a corresponding relationship with the unit step length. As shown in Table 4:

指示信息(索引)Instructions (index)	单位步长 Unit step
00	step0step0
11	step1step1

……	……
nn	stepnstepn

Table 4

Optionally, the indication information may also indicate a certain value in a numerical range. For example, if the determined TA change rate is 1.463, and its interval is between 1-2, both are indicated as a reference value (for example, 1.5). The specific correspondence can be shown in Table 5 below:

table 5

The numerical interval can be determined by satellite system parameters. For example, it can be based on factors such as the change range of the TA change rate, accuracy, or network overhead. It is also possible to consider dividing the indicator value interval into a certain number of intervals at equal intervals or non-equal intervals, and each index number corresponds to a certain reference value (fixed value) in a certain interval of values.

Optionally, an example of dividing the indicated value interval at non-equal intervals, the TA change rate within the coverage of a single satellite is S-shaped. If the reachable range of the TA change rate is divided based on the coverage area under a certain satellite, then The numerical interval division at the satellite edge coverage will be more dense, and the numerical interval division near the sub-satellite point is sparse.

It is understandable that the bit overhead of the indication can be saved and network resources can be saved by means of the above indication information.

The above-mentioned methods in the embodiments of the present application are all applicable to the regenerated satellite scenario and the transparent transmission satellite scenario. The following specifically describes the two scenarios and the relationship between the scenarios and the public TA change rate.

For the regenerative satellite scene. If the satellite orbit error and the terminal altitude are not considered, the TA change rate of each position in the satellite under-satellite coverage area will not change with time. At this time, the public TA change rate is not time-varying, and the various direct and indirect indications of the network equipment do not need to be updated over time. It can be understood that the terminal only needs to receive the public TA change rate once, and the subsequent follow-up will always follow this TA change rate Compensate TA value. If the influence of satellite orbit error and terminal altitude is considered, the TA change rate of each position of the satellite under-satellite coverage area will change over time, so it is necessary to continuously directly or indirectly indicate the public TA change rate.

For transparent satellite scenarios. Since the distance between the satellite and the ground station changes with time, the TA change rate of each location in the under-satellite coverage area will change in real time. The rate of change of TA is related to the following variables:

In the transparent transmission satellite scenario, the TA change rate of the terminal includes two parts, one part is the TA change rate of the user link (the link between the terminal and the satellite) TA ₁ ′, and the other part is the TA change rate of the feeder chain. The sum of the TA change rate TA ₂ ′ of the path (the link between the satellite and the base station). The TA rate of change is also related to the sum of the ratio of the Doppler frequency deviation f _{d of the} user link and the feeder link to the center frequency point f _c ; the TA rate of change is also the angle information θ ₁ and θ of the satellite, the terminal and the ground station ₂ functions.

It is understandable that, referring to the regenerated satellite scenario, in the transparent transmission satellite scenario, a part of the TA change rate may change with time, and the other part of the TA change rate may not change with time. At this time, the network device may indicate different or the same ways of indicating the rate of change of the two parts of the TA. The manner in which the terminal obtains the rate of change of the two parts of TA may also be different or the same. Specifically, factors such as the relationship between satellites, base stations, and terminals, and current network conditions can be combined.

It should be noted that in the following description of the specific TA change rate, various indication methods and related concepts can refer to the description in the public TA change rate. The related description of the specific TA change rate can also be applied to various indications and related descriptions of the public TA change rate.

In this embodiment of the application, the network device sends a TA update command (send TA value) in a certain period. The network device can also indicate the specific TA change rate of the terminal. In the TA update period, the terminal compensates the received TA value based on the specific TA change rate indicated by the network device.

Optionally, after the terminal accesses the network, the network device issues a TA update command and indicates the specific TA change rate of the terminal in a certain period. The terminal uses the specific TA change rate currently received to compensate the TA value previously received during the TA update period. Optionally, the change of the specific TA change rate is not very fast, and at the same time, saving signaling overhead can be considered. The network device can issue the specific TA change rate at the millisecond or second level.

It can be understood that the public TA change rate may be a periodic broadcast. The rate of change for a specific TA may be different for each terminal. Therefore, the transmission frequency can be different, that is, the specific TA change rate of each terminal may be different. For example, the transmission frequency with small changes is low, and the transmission frequency with large changes is high. Can be directed to send. Of course, the transmission frequency of different specific TA change rates can also be the same. In addition, the transmission period of the common TA change rate and the specific TA change rate may be the same.

Similar to the public TA change rate, in the embodiment of the present application, the network device indicates a specific TA change rate in a certain period. The specific TA change rate may be the complete value of the specific TA change rate, or indicate the difference between the specific TA change rate and the public TA change rate, or indicate the difference between the current specific TA change rate and the specific TA change rate issued last time value. If the indication needs to use the public TA change rate, its corresponding coverage area definition, and the explanation of the number of public TA change rates, indicator variables, indication position and indication method are the same as those described in the first embodiment.

The specific TA change rate indicated by the network device in the embodiment of the present application may be a specific TA change rate for a single terminal. It can also be a specific TA change rate for a group of terminals. Among them, groups of terminals are generally located in close geographic locations.

The specific TA change rate indicated by the network device in the embodiment of the present application may be the value of the specific TA change rate, or the value obtained by multiplying the specific TA change rate by a certain unit step (or scaling factor), or Equivalent information that can be converted to each other, or the amount of TA change calculated based on the TA change rate per unit time. The specific TA change rate or other related information indicated by the network device in the embodiment of this application can be carried in the system message block (System Information Block, SIB), radio resource control protocol (Radio Resource Control, RRC), and downlink control information (Downlink Control Information, DCI), Timing Advance Command (TAC), which are sent along with the downlink data in the Physical Downlink Shared Channel (PDSCH), or send a specific TA change rate or rate in a separately allocated PDSCH Other related information can be indicated independently, or combined with the TA update command.

It can be understood that the same as the foregoing description, the sending can be done by adding new fields or reusing the original fields.

The specific TA change rate indicated by the network device in the embodiment of the present application may be directly indicated, and may be indicated by indication information. For example, as shown in Table 6 below:

指示信息Instructions	特定TA变化率Specific TA change rate
00	SpecificRate0SpecificRate0
11	SpecificRate1SpecificRate1
……	……
nn	SpecificRatenSpecificRaten

Table 6

It can be understood that the indication information may also indicate the offset. The unit step size can also be combined with the instruction. At this time, the network device can agree with the terminal or directly send the unit step size instruction information. It can refer to Table 4.

Optionally, the indication information may also indicate a certain value in a numerical range. (You can refer to Table 5) When dividing the numerical interval, you can plan in a unified manner in units of satellites, or configure them separately according to different coverage areas. After the network device determines the variable of the specific TA change rate or other information to be indicated, the numerical interval is limited by the maximum range of the indicator variable, or limited by a certain offset range based on a certain reference value. Considering factors such as the range, accuracy, or the cost of the variable, the range of the variable can be divided into a certain number of intervals at equal or non-equal intervals, and each indication information corresponds to a certain value in a numerical interval.

Optionally, the form of periodically indicating the specific TA change rate in the embodiment of the present application is configurable. In some coverage areas, the difference between the specific TA change rates is small, and it is not necessary for the network device to periodically indicate the specific TA change rates to the terminals in these coverage areas. At this time, you can consider adding a flag bit, such as SpecificTARateIndicateFlag, to indicate whether a specific TA change rate needs to be sent periodically. Take the way of indicating the flag bit in SIB1 as an example:

It can be understood that if the flag indicates that there is no need to periodically issue a specific TA change rate, then there is only one specific TA change rate in the coverage area. The specific TA change rate at this time is similar to the public TA change rate

The above-mentioned specific TA change rate can also be applied to regenerated satellite scenarios and transparent transmission satellite scenarios.

For the regenerative satellite scenario, the specific TA change rate can be directly or indirectly indicated by the network device in different forms in the aforementioned manner in this embodiment. If the public TA change rate needs to be used, the indication of the public TA change rate part can refer to the above description of the public TA change rate.

For the transparent satellite scenario, the specific TA change rate of each location in the satellite under-satellite coverage area will change in real time. Optionally, in the transparent satellite transmission scenario, the base station may directly or indirectly indicate the specific TA change rate (here, the specific TA change rate of the entire link). The base station can directly indicate the specific TA change rate, or indicate the Doppler frequency offset information {f _d1 , f _d2 , f _c2 }, or indicate the angle information between the satellite and the terminal and the ground station {θ ₁ , θ ₂ }, or indicate the unit The amount of TA change over time. Optionally, in the transparent satellite scenario, another method for the base station to indicate a specific TA change rate is that the user link uses the aforementioned regenerative satellite scenario indication scheme, and the TA change rate of the feeder link is determined by the terminal according to the ground station (base station). ) The relative position information with the satellite is calculated by itself. Among them, the relative position information does not need to be sent in real time, it only needs to be sent once at a certain moment, or the relative position information is updated periodically.

Optionally, the ground station (base station) knows its own geographic location information, and can obtain the satellite ephemeris and the satellite's real-time orbit position. If the ground station (base station) issues its relative position information with the satellite to the terminal, the terminal can use the relative position information between the ground station (base station) and the satellite to calculate the TA change rate of the feeder link by itself.

As shown in Figure 14, the terminal can use the relative position information of the ground station and the satellite to calculate the rate of change of the feeder link TA. The vertical plane in Figure 14 is the satellite orbit plane, O represents the center of the earth, S represents the satellite whose orbit is a circular orbit, R is the distance between the center of the earth and the satellite orbit, r is the radius of the earth, and A is the ground station, and artificial determination is introduced. The reference point A', A'is a certain point of the ground station A on the projection of the satellite orbit on the surface of the earth. The relationship between the ground station A and the reference point A'can be expressed by angles β and θ, where β is the plane angle (that is, the angle between the plane OAA' and the satellite orbit plane∠COD), and θ is the orbit of the ground station A The projection angle of the plane (that is, the angle between OA and OA'∠AOA'), the angle parameter can also be equivalently expressed by the arc length l _AA' =θr. The geocentric angle between the satellite S and the reference point A'at the current time t is represented by φ(t)=ωt, where ω represents the relative angular velocity of the satellite S and the reference point A'. The angle parameter can also be represented by the arc length l _S'A' = φ(t)r equivalently, S'is the line connecting the satellite S and the center of the earth O and the focal point of the projection of the satellite orbit plane on the earth's surface. These three angle information {β, θ, φ(t)} or their equivalent information are used to express the relative position of the ground station A and the satellite S. C and D are the projections of ground station A and satellite S on a plane perpendicular to the satellite orbit plane.

At a time t _0, the ground station sends the following information to the terminal: corresponding to the angle between the plane β, the raceway surface of the projection angle θ A, t ₀ time satellite S and the projection reference point A 'of the geocentric angle φ (t ₀₎ =ωt ₀ or its equivalent arc length information, and the relative movement direction of S and A'. It is understandable that these parameters can be more or less, as long as the TA change rate of the feeder link can be calculated according to the previously agreed formula. Optionally, these parameters only need to be notified once at time t ₀ , and the terminal can calculate the TA change rate of the feeder link part by itself according to the agreed formula.

Here is an example calculation formula, according to known conditions:

AC=rcosθ, OC=rsinθ

SD=Rcosφ(t), OD=Rsinφ(t)

Because it is a ΔSAB right-angled triangle, there are: SA ² =AB ² +SB ²

AB ² ＝CD ² ＝OC ² +OD ² -2OC·ODcos∠COD

= R ² sin ² θ+R ² sin ² φ(t)-2Rrsinθsinφ(t)cosβ

It should be noted that the above method is used to indicate the TA change rate of the user link and the feeder link in segments. In order to ensure the consistency of protocol design, the information indication format of the regenerated satellite scene and the transparent satellite scene can be designed in a unified manner. Because the indication information of the feeder link segment is only valid for the transparent satellite scenario, a flag bit, such as TransparentIndicateFlag, can be added to indicate whether the indication information of the feeder link segment is valid. It is also possible to indicate that the feeder link segment information is invalid by setting some indicator parameters of the feeder link segment to specific preset values. For example, the angle information used in the above calculation formula is set to a value other than [-π,π] to indicate that the angle information is invalid.

Please refer to FIG. 6, which is a schematic diagram of the composition of a terminal provided by an embodiment of this application; it may include:

The transceiver unit 100 is configured to receive the timing advance TA update value sent by the base station and the beam cell number of the beam cell where the terminal is located;

The processing unit 200 is configured to obtain corresponding TA compensation information according to the beam cell number, and perform TA compensation according to the TA update value and the TA compensation information in the TA update period;

The transceiver unit 100 is further configured to use the TA value after TA compensation to send uplink data.

Optionally, when the terminal is located in the beam cell, the TA deviation of the terminal is the sum of the transmission delay TA deviation and the update period TA deviation, and the update period TA deviation is the round-trip transmission delay of the current location The product of the change rate and the duration of the current TA update cycle;

The TA compensation information includes TA compensation data or reference data used to obtain the TA compensation data;

Optionally, the reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the processing unit 200 is specifically configured to:

Optionally, the processing unit 200 obtains the round-trip transmission delay change rate of the corresponding position of the geocentric angle data according to the geocentric angle data and the satellite orbit height, specifically according to the following formula:

The processing unit 200 obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, specifically according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

The processing unit 200 obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the position corresponding to the satellite and the geocentric angle data, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

Optionally, the reference data includes satellite orbital height and Doppler frequency offset data of the current beam cell, and the processing unit 200 is further configured to:

Optionally, the processing unit 200 obtains the round-trip transmission delay change rate of the current position according to the Doppler data and the carrier frequency, specifically according to the following formula:

The processing unit 200 obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location, specifically according to the following formula:

ΔTA _trans =T _a ′×t _trans ;

The processing unit 200 obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay at the current location, and the current TA update period has continued for the duration of the TA deviation, specifically according to the following formula:

ΔTA=T _a ′×(t _trans +t _update );

It should be understood that, as an example of the multiple optional methods in this application, there may be other implementations in the case of satisfying the calculation idea of this application. For example, a reasonable mathematical distortion, increase or decrease a constant, or increase or decrease a parameter. This application does not restrict this.

Optionally, the processing unit 200 is specifically configured to:

Optionally, the TA compensation data further includes:

The processing unit 200 is specifically configured to:

Optionally, the processing unit 200 is specifically configured to:

Optionally, the processing unit 200 is further configured to:

Acquiring location information of the terminal;

When the processing unit 200 performs TA compensation according to the TA update value and the TA compensation information, it is specifically configured to:

Optionally, the terminal receives the TA update value sent by the base station, which is the TA update value sent by the base station after compensation according to the current transmission delay TA deviation.

For the concepts related to the technical solutions provided in the embodiments of the present application and related concepts, explanations, detailed descriptions, and other steps involved in the terminal, please refer to the descriptions of these contents in the foregoing method embodiments, which are not repeated here.

It can be understood that the unit of FIG. 6 can also be applied to the methods shown in FIGS. 9-13.

Please refer to FIG. 7, which is a schematic diagram of the composition of another terminal provided in an embodiment of this application; as shown in FIG. 7, the terminal may include a processor 110, a memory 120 and a bus 130. The processor 110 and the memory 120 are connected by a bus 130. The memory 120 is used to store instructions, and the processor 110 is used to execute the instructions stored in the memory 120 to implement the method corresponding to FIG. 2 to FIG. 5 or 10 to FIG. A step of.

Further, the terminal may also include an input port 140 and an output port 150. Among them, the processor 110, the memory 120, the input port 140 and the output port 150 may be connected via a bus 130.

The processor 110 is configured to execute instructions stored in the memory 120 to control the input port 140 to receive signals, and to control the output port 150 to send signals, so as to complete the steps performed by the terminal in the foregoing method. The input port 140 and the output port 150 may be the same or different physical entities. When they are the same physical entity, they can be collectively referred to as input and output ports. The memory 120 may be integrated in the processor 110, or may be provided separately from the processor 110.

As an implementation manner, the functions of the input port 140 and the output port 150 may be implemented by a transceiver circuit or a dedicated chip for transceiver. The processor 110 may be implemented by a dedicated processing chip, a processing circuit, a processor, or a general-purpose chip.

As another implementation manner, a general-purpose computer may be considered to implement the terminal provided in the embodiment of the present application. The program codes for realizing the functions of the processor 110, the input port 140 and the output port 150 are stored in the memory. The general purpose processor implements the functions of the processor 110, the input port 140 and the output port 150 by executing the code in the memory.

For the concepts related to the technical solutions provided by the embodiments of the present application related to the terminal, for explanations, detailed descriptions and other steps, please refer to the descriptions of these contents in the foregoing method or other embodiments, which are not repeated here.

Please refer to FIG. 8, which is a schematic diagram of the composition of a base station provided in an embodiment of this application; it may include:

The sending unit 300 is configured to send the timing advance TA update value and the beam cell number of the beam cell where the terminal is located to the terminal;

The receiving unit 400 is configured to receive uplink data sent by the terminal using the TA value after TA compensation;

The TA compensation information includes TA compensation data or reference data used to calculate the TA compensation data;

The TA compensation data includes: the maximum TA deviation, the minimum TA deviation, the maximum transmission delay TA deviation, and the minimum transmission delay TA deviation of the current beam cell;

Optionally, the base station may further include a processing unit, which may be used to divide beam cells.

Optionally, when the base station sends the TA update value, the processing unit of the base station may also compensate the TA update value according to the current transmission delay TA deviation before sending it.

For the concepts related to the technical solutions provided by the embodiments of the present application related to the base station, for explanations, detailed descriptions, and other steps, please refer to the descriptions of these contents in the foregoing method or other embodiments, which are not repeated here.

It can be understood that the unit of FIG. 8 can also be applied to the methods shown in FIGS. 9-13.

Please refer to FIG. 9, which is a schematic diagram of the composition of another terminal provided in an embodiment of this application; as shown in FIG. 9, the base station may include a processor 210, a memory 220 and a bus 230. The processor 210 and the memory 220 are connected by a bus 230. The memory 220 is used to store instructions, and the processor 210 is used to execute the instructions stored in the memory 220 to implement the method corresponding to FIGS. 2 to 5 or 10 to 14 above. Steps performed by the base station.

Further, the base station may further include an input port 240 and an output port 250. Among them, the processor 210, the memory 220, the input port 240, and the output port 250 may be connected through the bus 230.

The processor 210 is configured to execute instructions stored in the memory 220 to control the input port 240 to receive signals, and to control the output port 250 to send signals, so as to complete the steps performed by the base station in the foregoing method. The input port 240 and the output port 250 may be the same or different physical entities. When they are the same physical entity, they can be collectively referred to as input and output ports. The memory 220 may be integrated in the processor 210, or may be provided separately from the processor 210.

As an implementation manner, the functions of the input port 240 and the output port 250 may be implemented by a transceiver circuit or a dedicated chip for transceiver. The processor 210 may be implemented by a dedicated processing chip, a processing circuit, a processor, or a general-purpose chip.

As another implementation manner, a general-purpose computer may be considered to implement the terminal provided in the embodiment of the present application. The program codes for realizing the functions of the processor 210, the input port 240 and the output port 250 are stored in the memory. The general purpose processor implements the functions of the processor 210, the input port 240 and the output port 250 by executing the code in the memory.

Those skilled in the art can understand that, for ease of description, only one memory and processor are shown in FIG. 7 and FIG. 9. In an actual controller, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, etc., which is not limited in the embodiment of the present application.

It should be understood that, in the embodiments of the present application, the processor may be a central processing unit (Central Processing Unit, CPU for short), and the processor may also be other general-purpose processors, digital signal processors (Digital Signal Processing, DSP for short), Application Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc.

The memory may include read-only memory and random access memory, and provides instructions and data to the processor. A part of the memory may also include a non-volatile random access memory.

In addition to the data bus, the bus may also include a power bus, a control bus, and a status signal bus. However, for clear description, various buses are marked as buses in the figure.

In the implementation process, the steps of the above method can be completed by hardware integrated logic circuits in the processor or instructions in the form of software. The steps of the method disclosed in the embodiments of the present application may be directly embodied as being executed and completed by a hardware processor, or executed and completed by a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the field such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

According to the method provided in the embodiment of the present application, the embodiment of the present application also provides a system, which includes the aforementioned base station, terminal, satellite, etc.

In the various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not correspond to the implementation process of the embodiments of the present application. Constitute any limitation.

Those of ordinary skill in the art may realize that the various illustrative logical blocks (illustrative logical blocks, ILB) and steps described in the embodiments disclosed herein can be implemented by electronic hardware or a combination of computer software and electronic hardware. achieve. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media. The usable medium may be a magnetic medium, (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state hard disk).

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application. Should be covered within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A method for updating timing advance, characterized in that it includes:

The terminal receives the update value of the timing advance TA sent by the base station and the beam cell number of the beam cell where the terminal is located;

The terminal obtains corresponding TA compensation information according to the beam cell number;

In the TA update period, the terminal performs TA compensation according to the TA update value and the TA compensation information;

The terminal uses the TA value after TA compensation to send uplink data.
The method according to claim 1, wherein the TA compensation information comprises TA compensation data or reference data used to obtain the TA compensation data;

The TA compensation data includes: the maximum TA deviation and the minimum transmission delay TA deviation of the current beam cell;

The reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the geocentric angle data includes a maximum geocentric angle and a minimum geocentric angle;

Or the reference data includes: satellite orbit height and Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset .
The method according to claim 2, wherein the reference data includes satellite orbital height and geocentric angle data of the current beam cell, and the terminal obtains the geocentric angle data according to the geocentric angle data and the satellite orbital height The round-trip transmission delay change rate of the corresponding position of the geocentric angle data;

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data; or

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, and the duration of the current TA update period;

Wherein, the transmission delay TA deviation obtained by the terminal according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the terminal according to the minimum geocentric angle in the geocentric angle data The acquired transmission delay TA deviation is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is the minimum transmission time The sum of the TA deviation and the minimum update period TA deviation.
The method according to claim 3, wherein the terminal obtains the round-trip transmission delay change rate of the corresponding position of the geocentric angle data according to the geocentric angle data and the satellite orbit height, specifically according to the following formula get on:

Among them, T a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, c represents the speed of light, ω represents the relative angular velocity between the satellite and the user, R represents the radius of the earth, h represents the satellite orbit height, and θ represents the geocentric angle data;

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, specifically according to the following formula:

ΔTA trans =T a ′×t trans ;

Wherein, ΔTA trans represents the transmission delay TA deviation, and t trans represents the one-way transmission delay between the satellite and the corresponding position of the geocentric angle data;

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay between the satellite and the geocentric angle data, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T a ′×(t trans +t update );

Among them, ΔTA represents the TA deviation, and t update represents the duration of the current TA update cycle.
The method according to claim 2, wherein the reference data includes satellite orbital height and Doppler frequency offset data of the current beam cell, and the terminal obtains the current Doppler frequency offset data according to the Doppler frequency offset data and the carrier frequency. The round-trip transmission delay change rate of the location;

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location; or

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period;

Wherein, the transmission delay TA deviation obtained by the terminal according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the terminal according to the minimum geocentric angle in the geocentric angle data The acquired transmission delay TA deviation is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is the minimum transmission time The sum of the TA deviation and the minimum update period TA deviation.
The method according to claim 5, wherein the terminal obtains the round-trip transmission delay change rate of the current position according to the Doppler frequency offset data and the carrier frequency, specifically according to the following formula:

Among them, T a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, f c represents the carrier frequency, and f d represents the Doppler frequency deviation of the current position;

The terminal obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location, specifically according to the following formula:

ΔTA trans =T a ′×t trans ;

Wherein, ΔTA trans represents the transmission delay TA deviation, and t trans represents the one-way transmission delay between the satellite and the corresponding position of the geocentric angle data;

The terminal obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period, specifically according to the following formula:

ΔTA = T a ′×(t trans +t update ) ;

Among them, ΔTA represents the TA deviation, and t update represents the duration of the current TA update cycle.
The method according to any one of claims 2-6, wherein the terminal performing TA compensation according to the TA update value and the TA compensation information comprises:

When the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of the maximum TA deviation to perform TA compensation;

When the terminal and the satellite are far away from each other, the terminal subtracts the TA update value from the absolute value of the minimum transmission delay TA deviation to perform TA compensation.
The method according to claim 2, wherein the TA compensation data further comprises:

The minimum TA deviation and the maximum transmission delay TA deviation of the current beam cell;

The terminal performs TA compensation according to the TA update value and the TA compensation information, including: the terminal calculates each frame according to the TA compensation information and the ratio of the TA update period to the data frame length of the uplink data to be sent Frame TA deviation of data;

The terminal separately performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation.
The method according to claim 8, wherein when the terminal and the satellite are close to each other, the terminal calculates the frame TA of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length Deviations include:

The terminal calculates the frame TA deviation according to the maximum TA deviation, the maximum transmission delay TA deviation, and the ratio of the TA update period to the data frame length of the uplink data to be sent;

The terminal performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation, including:

The terminal selects the absolute value of the maximum transmission delay TA deviation and N times the frame TA deviation to add TA compensation for each frame of data in the TA update period, where N is the data frame Serial number, and N is an integer greater than or equal to 1.
8. The method according to claim 8, wherein when the terminal and the satellite are far away from each other, the terminal calculates the frame TA of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length Deviations include:

The terminal calculates the frame TA deviation according to the minimum TA deviation, the minimum transmission delay TA deviation, and the ratio of the TA update period to the data frame length of the uplink data to be sent:

The terminal performs TA compensation on the TA of each frame of data in the TA update period according to the frame TA deviation, including:

The terminal selects the negative value of the absolute value of the minimum transmission delay TA deviation and subtracts (N-1) times the frame TA deviation, and performs TA compensation on the TA of each frame of data in the TA update period. , Where N is the serial number of the data frame, and N is an integer greater than or equal to 1.
The method according to claim 1 or 8, characterized in that, the method further comprises:

Acquiring, by the terminal, location information of the terminal;

Determining, by the terminal, the relative position of the terminal in the beam cell according to the position information and the position of the edge point of the beam cell;

The terminal performs linearization processing on the TA deviation between the two edge points of the beam cell, and obtains the first slope of the linear change of the TA deviation according to the TA deviation of the two edge points of the beam cell, or according to the beam The transmission delay TA deviation of the two edge points of the cell acquires the second slope of the linear change of the transmission delay TA deviation;

Obtaining the TA deviation of the current position of the terminal according to the relative position of the terminal and the first slope, or obtaining the transmission delay TA deviation of the current position of the terminal according to the relative position of the terminal and the second slope;

The terminal performing TA compensation according to the TA update value and the TA compensation information includes:

When the terminal and the satellite are close to each other, the terminal adds the TA update value and the absolute value of the TA deviation of the current position of the terminal to perform TA compensation;

When the terminal and the satellite are far away from each other, the terminal subtracts the TA update value from the absolute value of the transmission delay TA deviation of the current position of the terminal to perform TA compensation.
The method according to any one of claims 1-11, characterized by comprising:

The TA update value sent by the terminal received by the base station is the TA update value sent by the base station after compensation according to the current transmission delay TA deviation.
A method for updating timing advance, characterized in that it includes:

The base station sends the timing advance TA update value and the beam cell number of the beam cell where the terminal is located to the terminal;

The base station receives the uplink data sent by the terminal using the TA value after TA compensation;

Wherein, the beam cell number corresponds to TA compensation information used by the terminal to perform TA compensation on the TA update value.
The method according to claim 13, wherein the TA compensation information comprises TA compensation data or reference data used to calculate the TA compensation data;

The TA compensation data includes at least one of the following: a maximum TA deviation, a minimum TA deviation, a maximum transmission delay TA deviation, and a minimum transmission delay TA deviation of the current beam cell;

The reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the geocentric angle data includes a maximum geocentric angle and a minimum geocentric angle;

Or the reference data includes: Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset.
A terminal, characterized in that it comprises:

The transceiver unit is used to receive the TA update value sent by the base station and the beam cell number of the beam cell where the terminal is located;

A processing unit, configured to obtain corresponding TA compensation information according to the beam cell number, and perform TA compensation according to the TA update value and the TA compensation information in the TA update period;

The transceiver unit is also configured to use the TA value after TA compensation to send uplink data.
The terminal according to claim 15, wherein the TA compensation information comprises TA compensation data or reference data used to obtain the TA compensation data;

The TA compensation data includes: the maximum TA deviation and the minimum transmission delay TA deviation of the current beam cell;

The reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the geocentric angle data includes a maximum geocentric angle and a minimum geocentric angle;

Or the reference data includes: Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset.
The terminal according to claim 16, wherein the reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the processing unit is specifically configured to:

Acquiring, according to the geocentric angle data and the satellite orbit height, the round-trip transmission delay change rate of the corresponding position of the geocentric angle data;

Obtain the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data; or

Obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, and the duration of the current TA update period;

Wherein, the transmission delay TA deviation obtained by the processing unit according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the processing unit according to the minimum geocentric angle data The transmission delay TA deviation obtained by the heart angle is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is the minimum The sum of the transmission delay TA deviation and the minimum update period TA deviation.
The terminal according to claim 17, wherein the processing unit is configured to obtain the round-trip transmission delay change rate of the corresponding position of the geocentric angle data according to the geocentric angle data and the satellite orbit height, specifically According to the following formula:

Among them, T a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, c represents the speed of light, ω represents the relative angular velocity between the satellite and the user, R represents the radius of the earth, h represents the satellite orbit height, and θ represents the geocentric angle data;

The processing unit obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay between the satellite and the position corresponding to the geocentric angle data, specifically according to the following formula:

ΔTA trans =T a ′×t trans ;

Wherein, ΔTA trans represents the transmission delay TA deviation, and t trans represents the one-way transmission delay between the satellite and the corresponding position of the geocentric angle data;

The processing unit obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the position corresponding to the satellite and the geocentric angle data, and the duration of the current TA update period, specifically according to the following formula:

ΔTA = T a ′×(t trans +t update ) ;

Among them, ΔTA represents the TA deviation, and t update represents the duration of the current TA update cycle.
The terminal according to claim 16, wherein the reference data includes satellite orbital height and Doppler frequency offset data of the current beam cell, and the processing unit is further configured to:

Obtaining the round-trip transmission delay change rate of the current position according to the Doppler frequency offset data and the carrier frequency;

Obtain the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current location; or

Obtain the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period;

Wherein, the transmission delay TA deviation obtained by the processing unit according to the maximum geocentric angle in the geocentric angle data is the maximum transmission delay TA deviation, and the processing unit according to the minimum geocentric angle data The transmission delay TA deviation obtained by the heart angle is the minimum transmission delay TA deviation, the maximum TA deviation is the sum of the maximum transmission delay TA deviation and the maximum update period TA deviation, and the minimum TA deviation is The sum of the minimum transmission delay TA deviation and the minimum update period TA deviation.
The terminal according to claim 19, wherein the processing unit obtains the round-trip transmission delay change rate of the current position according to the Doppler frequency offset data and the carrier frequency, specifically according to the following formula:

Among them, T a ′ represents the round-trip transmission delay change rate of the corresponding position of the geocentric angle data, f c represents the carrier frequency, and f d represents the Doppler frequency deviation of the current position;

The processing unit obtains the transmission delay TA deviation according to the round-trip transmission delay change rate and the one-way transmission delay of the current position, specifically according to the following formula:

ΔTA trans =T a ′×t trans ;

Wherein, ΔTA trans represents the transmission delay TA deviation, and t trans represents the one-way transmission delay between the satellite and the corresponding position of the geocentric angle data;

The processing unit obtains the TA deviation according to the round-trip transmission delay change rate, the one-way transmission delay of the current location, and the duration of the current TA update period, specifically according to the following formula:

ΔTA=T a ′×(t trans +t update ) ;

Among them, ΔTA represents the TA deviation, and t update represents the duration of the current TA update cycle.
The terminal according to any one of claims 16-20, wherein the processing unit is specifically configured to:

When the terminal and the satellite are close to each other, adding the TA update value and the absolute value of the maximum TA deviation to perform TA compensation;

When the terminal and the satellite are far away from each other, the TA update value is subtracted from the absolute value of the minimum transmission delay TA deviation to perform TA compensation.
The terminal according to claim 16, wherein the TA compensation data further comprises:

The minimum TA deviation and the maximum transmission delay TA deviation of the current beam cell;

The processing unit is specifically used for:

Calculate the frame TA deviation of each frame of data according to the TA compensation information and the ratio of the TA update period to the data frame length of the uplink data to be sent;

TA compensation is performed on the TA of each frame of data in the TA update period according to the frame TA deviation.
The terminal according to claim 22, wherein the processing unit is specifically configured to:

When the terminal and the satellite are close to each other, calculate the frame TA deviation according to the maximum TA deviation, the maximum transmission delay TA deviation, and the ratio of the TA update period to the data frame length of the uplink data to be sent;

The absolute value of the maximum transmission delay TA deviation is selected and added to the frame TA deviation of N times, and TA compensation is performed on the TA of each frame of data in the TA update period, where N is the sequence number of the data frame, and N is an integer greater than or equal to 1.
The terminal according to claim 22, wherein the processing unit is specifically configured to:

When the terminal and the satellite are far away from each other, the frame TA deviation is calculated according to the minimum TA deviation, the minimum transmission delay TA deviation, and the ratio of the TA update period to the data frame length:

The negative value of the absolute value of the minimum transmission delay TA deviation is selected to subtract (N-1) times the frame TA deviation, and TA compensation is performed on the TA of each frame of data in the TA update period, where N Is the serial number of the data frame, and N is an integer greater than or equal to 1.
The terminal according to claim 15 or 22, wherein the processing unit is further configured to:

Acquiring location information of the terminal;

Determine the relative position of the terminal in the beam cell according to the position information and the position of the edge point of the beam cell;

Linearize the TA deviation between the two edge points of the beam cell, obtain the first slope of the linear change of the TA deviation according to the TA deviation of the two edge points of the beam cell, or obtain the first slope of the linear change of the TA deviation according to the two edge points of the beam cell The transmission delay TA deviation of each edge point obtains the second slope of the linear change of the transmission delay TA deviation;

Obtaining the TA deviation of the current position of the terminal according to the relative position of the terminal and the first slope, or obtaining the transmission delay TA deviation of the current position of the terminal according to the relative position of the terminal and the second slope;

When the processing unit performs TA compensation according to the TA update value and the TA compensation information, it is specifically configured to:

When the terminal and the satellite are close to each other, adding the TA update value and the absolute value of the TA deviation of the current position of the terminal to perform TA compensation;

When the terminal and the satellite are far away from each other, the TA update value is subtracted from the absolute value of the transmission delay TA deviation of the current position of the terminal to perform TA compensation.
The terminal according to any one of claims 15-25, wherein the transceiving unit receives the TA update value sent by the network device, which is the TA sent by the base station after compensation according to the current transmission delay TA deviation. Update the value.
A base station, characterized in that it comprises:

The sending unit is used to send the timing advance TA update value and the beam cell number of the beam cell where the terminal is located to the terminal;

A receiving unit, configured to receive uplink data sent by the terminal using the TA value after TA compensation;

Wherein, the beam cell number corresponds to TA compensation information used by the terminal to perform TA compensation on the TA update value.
The base station according to claim 27, wherein when the terminal is located in the beam cell, the TA deviation of the terminal is the sum of the transmission delay TA deviation and the update period TA deviation, and the update period TA The deviation is the product of the round-trip transmission delay change rate of the current position and the duration of the current TA update cycle;

The TA compensation information includes TA compensation data or reference data used to calculate the TA compensation data;

The TA compensation data includes at least one of the following: a maximum TA deviation, a minimum TA deviation, a maximum transmission delay TA deviation, and a minimum transmission delay TA deviation of the current beam cell;

The reference data includes satellite orbit height and geocentric angle data of the current beam cell, and the geocentric angle data includes a maximum geocentric angle and a minimum geocentric angle;

Or the reference data includes: Doppler frequency offset data of the current beam cell, and the Doppler frequency offset data includes the absolute value of the maximum Doppler frequency offset and the absolute value of the minimum Doppler frequency offset.
A communication method, characterized in that the method includes:

The terminal receives the TA value sent by the network device;

Acquiring, by the terminal, a TA change rate corresponding to the terminal; compensating the TA value according to the TA change rate corresponding to the terminal;

Communicating with the network device according to the compensated TA value.
The method according to claim 29, wherein the terminal acquiring the TA change rate corresponding to the terminal comprises any combination of one or more of the following methods:

The terminal receives one or more TA change rates, and selects the TA change rate corresponding to the terminal from the one or more TA change rates; or

The terminal receives the TA change rate indication information, and obtains the TA change rate corresponding to the terminal according to the received TA change rate indication information, where the TA change rate indication information and the TA change rate The TA change rate corresponding to the terminal has a corresponding relationship; or

The terminal receives equivalent information, and obtains the TA change rate corresponding to the terminal according to the equivalent information; or

The terminal obtains the TA change rate corresponding to the terminal and stored in the terminal.
The method according to claim 30, wherein the TA change rate includes one or more of the following:

The offset of the TA change rate, the scaling value of the TA change rate based on a unit step, or the TA change amount per unit time;

Wherein, the unit step size or unit time is pre-configured or received from the network device;

The received from the network device includes that the terminal receives the unit step size or the unit time, or receives the unit step size indication information or the unit time indication information.
The method according to claim 30, wherein the correspondence relationship further comprises a correspondence relationship between a coverage area and the TA change rate indication information, and/or a correspondence relationship between a reference position and the TA change rate indication information.
The method according to any one of claims 30-32, wherein the terminal acquiring the TA change rate corresponding to the terminal according to equivalent information comprises:

According to equivalent information, select one of the TA change rates corresponding to the terminal from the one or more received TA change rates; or

According to the equivalent information, the TA change rate corresponding to the terminal is calculated.
The method according to claim 33, wherein the equivalent information includes one or more of the following: Doppler frequency offset, orbit height and elevation angle between the terminal and the network device, orbit height, and the terminal and the The opening angle of the network device, or the track height and the geocentric angle between the terminal and the network device.
The method according to any one of claims 29-34, wherein before the terminal compensates the TA value according to the TA change rate corresponding to the terminal, the method further comprises: To adjust the TA change rate corresponding to the terminal.
The method according to any one of claims 29-35, wherein the TA change rate comprises one or more of the following:

Public TA change rate, specific TA change rate, the difference between the public change rate and the TA change rate, or the difference between two specific TA change rates;

Wherein, the public TA change rate is the TA change rate of a reference location in the coverage area of the network device;

The specific TA change rate is the TA change rate at the location of the terminal.
The method according to claim 36, wherein the coverage area includes one or more cells covered by the network device, a projection area of one or more beams of the network device on the ground, and one or more cells covered by the network device A part of an area of a cell, or a part of an area where a beam of the network device is projected on the ground.
The method according to any one of claims 29-37, wherein the TA change rate, the TA change rate indication information, the equivalent information, the unit step size, or the unit time is Received through one or more of the following information, SIB, RRC, DCI, MIB, TAC, PDSCH.
The method according to any one of claims 29-38, wherein the TA change rate, the TA change rate indication information, the equivalent information, the unit step size, or the unit time and The TA value is received in the same message or in different messages; or,

The TA change rate indication information, the equivalent information, the unit step size, or the unit time is the same as or different from the sending period of the TA value.
The method according to any one of claims 29-39, wherein the TA change rate, the TA change rate indication information, the equivalent information, the unit step size, or the unit time, New fields in the information, or reuse of the original fields in the information.
The method according to any one of claims 29-40, wherein the compensating the TA value according to the TA change rate corresponding to the terminal comprises, in a TA update period, according to the The TA change rate corresponding to the terminal compensates the TA value.
The method according to any one of claims 29-41, wherein the terminal acquiring the TA change rate corresponding to the terminal comprises acquiring the TA change rate corresponding to the terminal during initial access.
The method according to any one of claims 29-42, wherein the terminal obtaining the TA change rate corresponding to the terminal includes two methods, one of which is to obtain the TA change rate corresponding to the terminal Another method is to obtain the other part of the TA change rate corresponding to the terminal.
A communication method, characterized in that the method includes:

The network device sends the TA value to one or more terminals;

The network device sends one or more of the following information: TA change rate, TA change rate indication information, equivalent information, unit step size, or unit time;

The network device communicates with the terminal according to the TA value.
The method according to claim 44, wherein the TA change rate includes one or more of the following:

The offset of the TA change rate, the scaling value of the TA change rate based on a unit step, or the TA change amount per unit time;

Wherein, the unit step size or unit time is pre-configured or sent by the network device;

What the network device sends includes sending the unit step size or the unit time, or sending the unit step length indication information or the unit time indication information.
The method according to claim 44 or 45, wherein the change rate indication information has a corresponding relationship with the TA change rate, and the corresponding relationship further includes a corresponding relationship between a coverage area and the TA change rate indication information and /Or, the corresponding relationship between the reference position and the TA change rate indication information.
The method according to any one of claims 44-46, wherein the equivalent information includes one or more of the following: Doppler frequency offset, orbit height and elevation angle between the terminal and the network device, orbit The height and the opening angle between the terminal and the network device, or the track height and the geocentric angle between the terminal and the network device.
The method according to any one of claims 44-47, wherein the TA change rate comprises one or more of the following:

Public TA change rate, specific TA change rate, the difference between the public change rate and the TA change rate, or the difference between two specific TA change rates;

Wherein, the public TA change rate is the TA change rate of a reference location in the coverage area of the network device;

The specific TA change rate is the TA change rate at the location of the terminal.
The method according to claim 48, wherein the coverage area includes one or more cells covered by the network device, a projection area of one or more beams of the network device on the ground, and one or more cells covered by the network device A part of a cell area, or a part of the area where a beam of the network device is projected on the ground.
The method according to any one of claims 44-49, wherein the sending one or more of the following information includes sending through SIB, RRC, DCI, MIB, TAC, or PDSCH.
The method according to any one of claims 44-49, wherein the sending one or more of the following information is not sent simultaneously with the sending TA information, or the sending the following information One or more types are sent simultaneously with the sending TA information; or,

The sending one or more of the following information is the same or different from the period of sending the TA information.
A terminal, characterized in that it comprises:

The transceiver unit is used to receive the TA value sent by the network device;

An acquiring unit, configured to acquire the TA change rate corresponding to the terminal; compensate the TA value according to the TA change rate corresponding to the terminal;

The transceiver unit is further configured to communicate with the network device according to the compensated TA value.
The terminal according to claim 52, wherein the acquiring unit configured to acquire the TA change rate corresponding to the terminal comprises one or any combination of the following:

The transceiving unit is further configured to receive one or more TA change rates, and the acquiring unit is specifically configured to select the TA change corresponding to the terminal from the one or more TA change rates received Rate; or

The transceiving unit is further configured to receive TA change rate indication information, and the acquiring unit is specifically configured to obtain the TA change rate corresponding to the terminal according to the received TA change rate indication information, where: The TA change rate indication information has a corresponding relationship with the TA change rate corresponding to the terminal; or

The transceiving unit is further configured to receive equivalent information, and the acquiring unit is configured to acquire the TA change rate corresponding to the terminal according to the equivalent information; or

The acquiring unit is specifically configured to acquire the TA change rate corresponding to the terminal and stored in the terminal.
The terminal according to claim 53, wherein the acquiring unit configured to acquire the TA change rate corresponding to the terminal according to the equivalent information comprises:

The acquiring unit is specifically configured to select the TA change rate corresponding to the terminal from one or more TA change rates received by the transceiver unit according to the equivalent information; or

According to the equivalent information, the TA change rate corresponding to the terminal is calculated.
The terminal according to claim 54, wherein the equivalent information includes one or more of the following: Doppler frequency offset, orbit height and elevation angle between the terminal and the network device, orbit height and the terminal and The opening angle of the network device, or the height of the track and the geocentric angle between the terminal and the network device.
The terminal according to any one of claims 52-55, wherein:

The acquiring unit is further configured to adjust the TA value according to one or more TA values received by the transceiver unit before the transceiver unit compensates the TA value according to the TA change rate corresponding to the terminal. The rate of change of TA.
The apparatus according to any one of claims 52-56, wherein the acquiring unit is configured to compensate the TA value according to the TA change rate corresponding to the terminal, and is specifically configured to: Inside, the TA value is compensated according to the TA change rate corresponding to the terminal.
The apparatus according to any one of claims 52-57, wherein the acquiring unit is configured to acquire the TA change rate corresponding to the terminal, and is specifically configured to acquire the TA change rate during initial access. The TA change rate corresponding to the terminal.
A network device, characterized by comprising: a sending unit, configured to send a TA value to one or more terminals;

The sending unit is further configured to send one or more of the following information: TA change rate, TA change rate indication information, equivalent information, unit step size, or unit time;

The receiving unit is used to communicate with the terminal according to the TA value together with the sending unit.
The network device according to claim 59, wherein the sending unit is specifically configured to send information through SIB, RRC, DCI, MIB, TAC, or PDSCH.
A device, characterized in that it comprises:

A processor, a memory, and a bus, the processor and the memory are connected by a bus, wherein the memory is used to store a set of program codes, and the processor is used to call the program codes stored in the memory, so that the -12, or any one of claims 13-14, or any one of claims 29-43, or any one of claims 44-51, are executed.
A computer-readable storage medium, characterized in that it comprises:

The computer-readable storage medium stores instructions, when it runs on a computer, such as any one of claims 1-12, or any one of claims 13-14, or any one of claims 29-43, Or the method of any one of claims 44-51 is executed.
A computer program product, which contains instructions that when run on a computer, causes the computer to execute any one of claims 1-12, or any one of claims 13-14, or claim 29- Any one of 43, or the method of any one of claims 44-51 is executed.