CN109842932B

CN109842932B - Method and device for acquiring time advance

Info

Publication number: CN109842932B
Application number: CN201711189814.4A
Authority: CN
Inventors: 卓永宁; 魏冬冬; 朱立东
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-11-24
Filing date: 2017-11-24
Publication date: 2021-06-22
Anticipated expiration: 2037-11-24
Also published as: WO2019101186A1; CN109842932A

Abstract

The embodiment of the application discloses a method and a device for acquiring a time advance in a communication network. The method comprises the following steps: the terminal determines the difference value of the clock information of the terminal and the network equipment through information interaction with the network equipment, and the terminal determines the time lead according to the time information of the terminal and the network equipment, or the terminal determines the position information of the terminal and the ephemeris information of the network equipment through information interaction with the network equipment and determines the time lead according to the time information of the terminal and the network equipment. The time lead is directly obtained at the terminal side, so that the error of the time lead measurement in the traditional time synchronization process is reduced, the uplink signal sent by the terminal can be correctly decoded, the time for adjusting the time lead is reduced, and the signaling overhead is reduced.

Description

Method and device for acquiring time advance

Technical Field

The embodiment of the application relates to a communication technology, in particular to a time synchronization technology.

Background

In a wireless communication system based on Orthogonal Frequency Division Multiplexing (OFDM) technology, in order to ensure that orthogonality is maintained between uplink transmissions of a plurality of terminals accessing a base station, different terminals adjust uplink transmission time according to a Timing Advance (TA), so that signals transmitted by different terminals reach the base station within an error range of the length of a Cyclic Prefix (CP), thereby implementing uplink synchronization.

In an existing Long Term Evolution (LTE) system, an evolved node B (eNode B) may measure a transmission delay according to a preamble sequence sent by a terminal through a Physical Random Access Channel (PRACH), so as to obtain a TA value. Then, a TA value is fed back to the terminal in a Random Access Response (RAR) message, and the terminal adjusts the uplink sending time according to the TA value. In the 5G communication system, there is also a process in which the network device measures the TA value and feeds back it to the terminal.

However, the cell range and the terminal moving speed to which the TA value acquisition mechanism of the existing LTE system is applied are small. In a communication system with a fast moving network element, the signal coverage of the network device is much larger than that of a ground cell, and the network device moves fast relative to the terminal. In such a communication scenario, the existing method for acquiring the TA value in the LTE system has obvious disadvantages: the TA value error is large, and the delay error of different terminals reaching the base station may exceed the length of one CP, so that the uplink signal transmitted by the terminal cannot be decoded correctly.

Disclosure of Invention

The embodiment of the application provides a method and a device for acquiring a time advance, and the TA value is acquired at a terminal side, so that the measurement error of the TA value can be reduced, and the decoding success rate of an uplink signal sent by the terminal is improved.

In a first aspect, an embodiment of the present application provides a method for acquiring a timing advance, where a terminal sends a first message to a network device, where the first message carries first time information of the terminal. The terminal further receives a second message and records second time information, wherein the second message is a message of the network device bearing the first time information of the network device, the second time information and the first time information of the terminal, or the second message is a message of the network device bearing the difference value between the first time information of the network device and the first time information of the terminal and the second time information of the network device. And the terminal determines the difference value between the clock information of the terminal and the clock information of the network equipment according to the time information of the terminal and the time information of the network equipment. And after determining the difference value of the clock information, the terminal receives a third message, wherein the third message carries third time information of the network equipment. And the terminal determines the transmission time delay of the terminal and the network equipment according to the third time information of the network equipment and the third time information of the terminal so as to determine the TA value. The TA value is obtained at the terminal side, so that the retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced.

In a possible implementation manner, the terminal receives a second message, where the second message carries a difference between the first time information of the network device and the first time information of the terminal, and second time information of the network device. The terminal determines a difference value between the terminal and the clock information of the network device according to the difference value and the first time information of the terminal and the second time information of the terminal, and after the difference value between the terminal and the clock information of the network device is determined, the transmission delay of the terminal and the transmission delay of the network device can be determined to obtain a TA value. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the network equipment side, so that the hardware complexity of the terminal side can be reduced.

In a possible implementation manner, the terminal receives a second message, where the second message carries the first time information of the network device, the second time information of the network device, and the first time information of the terminal. And the terminal determines the difference value between the clock information of the network equipment and the clock information of the network equipment according to the first time information of the network equipment and the second time information of the network equipment, and determines the transmission delay of the terminal and the network equipment after determining the difference value between the clock information of the network equipment and the clock information of the network equipment so as to obtain a TA value. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the terminal side, so that the hardware complexity of the network equipment can be reduced.

In a possible implementation manner, in the random access process, the terminal and the network device perform the following interaction process of time information: and the terminal sends the first message to the network equipment. And the terminal receives a second message of the network equipment and records second time information. After the difference between the clock information of the network device and the clock information is determined, the terminal further determines the transmission delay between the terminal and the network device according to third time information carried in a third message sent by the network device and the third time information of the terminal, so as to determine the TA value. The third time information of the network device is carried in the third message, which can save signaling overhead in the process of obtaining the TA value.

In a second aspect, an embodiment of the present application provides a method for obtaining a timing advance, where a network device sends a second message to a terminal, where the second message carries first time information of the network device, second time information of the network device, and first time information of the terminal, or the second message may also carry a difference between the first time information of the network device and the first time information of the terminal, and second time information of the network device. And the network equipment issues a third message carrying third time information of the network equipment to the terminal. And the third time information of the network equipment is used for determining the transmission delay and the TA value of the terminal and the network equipment. And the terminal determines the transmission delay according to the third time information of the terminal and the third time information of the network equipment so as to determine a TA value. The TA value is obtained at the terminal side, so that the retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced.

In a possible implementation manner, the network device sends a second message, where the second message carries a difference between the first time information of the network device and the first time information of the terminal, and second time information of the network device. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the network equipment side, so that the hardware complexity of the terminal side can be reduced.

In a possible implementation manner, the network device sends a second message, where the second message carries the first time information of the network device, the second time information of the network device, and the first time information of the terminal. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the terminal side, so that the hardware complexity of the network equipment can be reduced.

In a possible implementation manner, the terminal and the network device perform the following interaction process of time information: and the network equipment sends a second message to the terminal, and the network equipment issues a third message, wherein the third message carries third time information of the network equipment. The third time information of the network device is carried in the third message, so that the sending of the TA adjustment signaling of the network device can be avoided, and the signaling overhead is saved.

In one possible implementation, in the contention-based random access procedure, the first message may be a random access preamble message; the second message may be a random access response message. Optionally, the first message and the second message may also be other messages of a contention-based random access procedure, so that redefinition of the messages may be avoided.

In one possible implementation manner, in the contention-based random access procedure, the first message may be a message (Msg) 3; the second message may be a contention resolution message. Optionally, the first message and the second message may also be other messages of a contention-based random access procedure, so that redefinition of the messages may be avoided.

In one possible implementation manner, in the non-contention based random access procedure, the first message may be a random access preamble message, and the second message may be a random access response message. Optionally, the first message and the second message may also be other messages of a non-contention based random access procedure, so that redefinition of the messages may be avoided.

In a possible implementation manner, in a communication scenario of a satellite and a ground terminal adopting an orthogonal frequency division multiplexing modulation method, the ground terminal may be a mobile phone, a cellular phone, a personal digital assistant, a handheld device, or the like, and the network device may be a satellite or may be a ground station that is forwarded by the satellite. In a satellite fast mobile communication scene, the TA value is obtained at the terminal side, so that retransmission of the TA value from the network equipment side to the terminal side can be avoided, and errors of the TA value are reduced.

In a third aspect, an embodiment of the present application provides a terminal, including a transmitter, a receiver, and a processor.

The transmitter is configured to send a first message, where the first message carries first time information of the terminal.

The receiver is configured to receive a second message, where the second message carries the first time information of the network device, the second time information of the network device, and the first time information of the terminal, or the second message carries a difference between the first time information of the network device and the first time information of the terminal, and the second time information of the network device; the receiver is further configured to receive a third message, where the third message carries third time information of the network device.

And the processor determines the difference value of the clock information of the terminal and the network equipment according to the difference value of the first time information of the network equipment and the first time information of the terminal and the difference value of the second time information of the network equipment and the second time information of the terminal. And after determining the clock information difference value, the processor determines the transmission delay of the terminal and the network equipment according to the third time information of the terminal and the third time information of the network equipment so as to determine the TA value. The third time information of the terminal is the time information when the terminal receives the third message. The TA value is obtained at the terminal side, so that retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced.

In a possible implementation manner, the processor is configured to calculate a clock difference between the terminal and the network device according to a difference between the first time information of the terminal and the first time information of the network device, the second time information of the terminal, and the second time information of the network device. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the network equipment side, so that the hardware complexity of the terminal side can be reduced.

In a possible implementation manner, the processor is configured to calculate a clock difference between the terminal and the network device according to the first time information of the terminal, the first time information of the network device, the second time information of the terminal, and the second time information of the network device. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the terminal side, so that the hardware complexity of the network equipment side can be reduced.

In a fourth aspect, an embodiment of the present application provides a network device apparatus, which includes a transmitter, a receiver, and a processor.

The receiver is configured to receive a first message, where the first message carries first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message.

The processor is configured to calculate a difference between first time information of the terminal and first time information of the network device, where the first time information of the network device is time information when the network device receives a first message.

The transmitter is configured to issue a third message, where the third message carries third time information of the network device, and the third time information of the network device is time information when the network device sends the third message.

In a possible implementation manner, the transmitter is configured to send a second message, where the second message carries a difference between the first time information of the terminal and the first time information of the network device, and second time information of the network device, and the second time information of the network device is time information when the network device sends the second message. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the network equipment side, so that the hardware complexity of the terminal side can be reduced.

In a possible implementation manner, the transmitter is configured to issue a second message, where the second message carries first time information of the terminal, first time information of the network device, and second time information of the network device. And determining the difference value between the first time information of the network equipment and the first time information of the terminal at the terminal side, so that the hardware complexity of the network equipment side can be reduced.

In a fifth aspect, an embodiment of the present application provides a terminal, which includes a transceiver module and a determination module.

The receiving and sending module sends a first message, wherein the first message carries first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message.

The transceiver module may further receive a second message, where the second message carries the first time information of the network device, the second time information of the network device, and the first time information of the terminal, or the second message carries a difference between the first time information of the network device and the first time information of the terminal, and the second time information of the network device. The first time information of the network device is the time information when the network device receives the first message, and the second time information of the network device is the time information when the network device sends the second message.

The transceiver module may further receive a third message, where the third message carries third time information of the network device. The third time information of the network device is time information when the network device sends a third message.

The determining module determines the difference value between the clock information of the network device and the clock information of the network device according to the difference value between the first time information of the network device and the first time information of the terminal and the difference value between the second time information of the network device and the second time information of the terminal. And after the determining module determines the clock information difference, determining the transmission delay between the terminal and the network equipment according to the third time information of the terminal and the third time information of the network equipment so as to determine the TA value. The TA value is obtained at the terminal side, so that retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced. The terminal determines the transmission delay according to the third time information of the terminal and the third time information of the network device to determine the TA value, so that the transmission of TA adjustment signaling of the network device can be avoided, and the signaling overhead is saved.

In a sixth aspect, an embodiment of the present application provides a network device, which includes a transceiver module and a recording module.

The receiving and sending module is used for receiving a first message, the first message carries first time information of the terminal, the first time information of the terminal is time information when the terminal sends the first message, and the recording module records the first time information of the terminal.

And the transceiver module sends a second message, wherein the second message carries the first time information of the network equipment, the second time information of the network equipment and the first time information of the terminal. The first time information of the network equipment is the time information when the network equipment receives a first message, the second time information of the network equipment is the time information when the network equipment sends a second message, and the recording module records the first time information of the network equipment and the second time information of the network equipment.

The transceiver module sends a third message, the third message carries a third message of third time information of the network device, the third time information of the network device is time information when the network device issues the third message, and the recording module records the third time information of the network device.

In a seventh aspect, an embodiment of the present application provides a network device, including a transceiver module and a determining module.

The receiving and sending module is used for receiving a first message, the first message carries first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message.

And the transceiver module sends a second message, wherein the second message carries a difference value between the first time information of the network equipment and the first time information of the terminal and second time information of the network equipment. The first time information of the network device is the time information when the network device receives the first message, and the second time information of the network device is the time information when the network device sends the second message.

The transceiver module may further be configured to send a third message, where the third message carries third time information of the network device, and the third time information of the network device is time information when the network device sends the third message.

The determining module is configured to determine a difference between the first time information of the network device and the first time information of the terminal.

In an eighth aspect, an embodiment of the present application provides a method for acquiring a timing advance, where a terminal sends a first message to a network device, and the first message carries first time information of the terminal. The terminal further receives a second message, where the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second message may also carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device. The first location information of the network device is location information when the network device receives a first message, and the second location information of the network device is location information when the network device sends a second message. The terminal acquires the position information of the terminal and the ephemeris information of the network equipment according to the first time information of the network equipment, the first time information of the terminal, the second time information of the network equipment, the second time information of the terminal, the first position information of the network equipment and the second position information of the network equipment, wherein the second time information of the terminal is the time information when the terminal receives the second message; the terminal may further obtain the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device. And the terminal receives a third message received by the terminal, wherein the third message comprises third time information of the network equipment. And the terminal determines the transmission delay of the terminal and the network equipment according to the third time information of the network equipment, the third time information of the terminal, the position information of the terminal and the ephemeris information of the network equipment so as to determine the TA value. The TA value is obtained at the terminal side, so that the retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced. When calculating the TA value, the position information of the terminal, the position information of the network device, and the ephemeris information of the network device are also taken into consideration, so that the error of the TA value can be further reduced.

In a possible implementation manner, in the random access process, the terminal and the network device perform the following interaction process of time information: and the terminal sends the first message to the network equipment. And the terminal receives a second message of the network equipment. Through the interaction of the random access process, the terminal acquires the position information of the terminal and the ephemeris information of the network equipment. After obtaining the position information of the terminal and the ephemeris information of the network device, the terminal further determines a transmission delay between the terminal and the network device according to third time information of the network device and third time information of the terminal, which are carried in a third message issued by the network device, so as to determine a TA value. The third time information of the network device is carried in the third message, which can save signaling overhead in the process of obtaining the TA value.

In one possible implementation, in the contention-based random access procedure, the first message may be message 3; the second message may be a contention resolution message. Optionally, the first message and the second message may also be other messages of a contention-based random access procedure, so that redefinition of the messages may be avoided.

In a ninth aspect, an embodiment of the present application provides a method for obtaining a timing advance, where a network device sends a second message to a terminal, where the second message carries first time information of the network device, second time information of the network device, first time information of the terminal, first location information of the network device, and second location information of the network device; the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device. The first location information of the network device is location information when the network device receives a first message, and the second location information of the network device is location information when the network device sends a second message. And the network equipment issues a third message carrying third time information of the network equipment to the terminal. And the third time information of the network equipment is used for determining the transmission delay and the TA value of the terminal and the network equipment. And the terminal determines the transmission delay according to the third time information of the terminal and the third time information of the network equipment so as to determine a TA value. The TA value is obtained at the terminal side, so that the retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced.

In a tenth aspect, an embodiment of the present application provides a terminal, including a transmitter, a receiver, and a processor.

The receiver is configured to receive a second message, where the second message carries first time information of the network device, second time information of the network device, first time information of the terminal, first location information of the network device, and second location information of the network device; the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device. The first position information of the network equipment is position information when the network equipment receives a first message, and the second position information of the network equipment is position information when the network equipment sends a second message; the receiver is further configured to receive a third message, where the third message carries third time information of the network device.

The processor acquires the position information of the terminal and the ephemeris information of the network equipment according to the first time information of the network equipment, the first time information of the terminal, the second time information of the network equipment, the second time information of the terminal, the first position information of the network equipment and the second position information of the network equipment; the processor may further obtain the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device. After the processor acquires the position information of the terminal and the ephemeris information of the network device, determining transmission delays of the terminal and the network device according to the third time information of the network device, the third time information of the terminal, the position information of the terminal and the ephemeris information of the network device to determine a TA value. The TA value is obtained at the terminal side, so that retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced. When calculating the TA value, the position information of the terminal, the position information of the network device, and the ephemeris information of the network device are also taken into consideration, so that the error of the TA value can be further reduced.

In an eleventh aspect, an embodiment of the present application provides a network device apparatus, which includes a transmitter, a receiver, and a processor.

The receiver is configured to receive a first message, where the first message carries first time information of the terminal.

The processor is configured to obtain first location information of the network device and second location information of the network device.

The transmitter is configured to issue a third message, where the third message carries third time information of the network device. The transmitter is further configured to send a second message, where the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second message may also carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device.

In a twelfth aspect, an embodiment of the present application provides a terminal, which includes a transceiver module and a determining module.

And the transceiver module sends a first message, wherein the first message carries first time information of the terminal.

The transceiver module may further receive a second message, where the second message carries information of the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device; the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device. The first location information of the network device is location information when the network device receives a first message, and the second location information of the network device is location information when the network device sends a second message.

The transceiver module may further receive a third message, where the third message carries third time information of the network device.

The determining module obtains the position information of the terminal and the ephemeris information of the network device according to the first time information of the network device, the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first position information of the network device and the second position information of the network device. The determining module may further obtain the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device. After the position information of the terminal and the ephemeris information of the network device are obtained, the determining module determines a transmission delay according to the position information of the terminal, the ephemeris information of the network device, the third time information of the network device, and the third time information of the terminal to determine a TA value.

The TA value is obtained at the terminal side, so that retransmission of the TA value from the network equipment side to the terminal side can be avoided, and the error of the TA value is reduced. And when the TA value is determined, the position information of the terminal, the position information of the network equipment and the ephemeris information of the network equipment are also taken into account, so that the error of the TA value is further reduced. The terminal determines the transmission delay according to the third time information of the terminal and the third time information of the network device to determine the TA value, so that the transmission of TA adjustment signaling of the network device can be avoided, and the signaling overhead is saved. And the recording module records second time information of the terminal.

In a thirteenth aspect, an embodiment of the present application provides a network device apparatus, including a transceiver module and a determining module.

The receiving and sending module is used for receiving a first message, and the first message carries first time information of the terminal.

The transceiver module sends a second message, wherein the second message comprises first time information of the network device, first time information of the terminal, second time information of the network device, first position information of the network device and second position information of the network device; the second message may further include a difference value between the first time information of the network device and the first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device. The first location information of the network device is location information when the network device receives a first message, and the second location information of the network device is location information when the network device sends a second message.

The transceiver module may be further configured to send a third message, where the third message carries third time information of the network device.

The determining module is configured to obtain first location information of the network device and second location information of the network device.

In a fourteenth aspect, an embodiment of the present application provides a chip system, including: the chip system comprises at least one processor, a memory and an interface circuit, wherein the memory, the transceiver and the at least one processor are interconnected through lines, and instructions are stored in the at least one memory; the instructions are executed by the processor to perform the method of the first, eighth, or any alternative implementation of the first, eighth aspects.

In a fifteenth aspect, an embodiment of the present application provides a chip system, including: the chip system comprises at least one processor, a memory and an interface circuit, wherein the memory, the transceiver and the at least one processor are interconnected through lines, and instructions are stored in the at least one memory; the instructions are executed by the processor to perform the method of the second, ninth aspect or any alternative implementation of the second, ninth aspect.

In a sixteenth aspect, an embodiment of the present application provides a computer-readable storage medium, which can be applied in a terminal, and the computer-readable storage medium stores instructions that, when executed on a computing device, perform the method described in the first or eighth aspect or any optional implementation manner of the first or eighth aspect.

In a seventeenth aspect, the present application provides a computer-readable storage medium, which can be applied to a network device, and has instructions stored therein, where the instructions, when executed on a computing device, perform the method described in the second or ninth aspect or any optional implementation manner of the second or ninth aspect.

In an eighteenth aspect, the present application provides a communication system, where the communication system includes at least one network device mentioned in the fourth and eleventh aspects.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.

Fig. 1 depicts a schematic view of a wireless communication system according to an embodiment of the present application;

fig. 2 depicts a schematic diagram of a contention-based random access procedure;

fig. 3 depicts a diagram of a non-contention based random access procedure;

fig. 4 is a schematic diagram of a synchronization signal block provided in an embodiment of the present application;

fig. 5 is a flowchart for acquiring a timing advance according to an embodiment of the present application;

fig. 6 is a flowchart of acquiring timing advance in a contention-based random access procedure according to an embodiment of the present application;

fig. 7 is a flowchart for acquiring a timing advance in a non-contention based random access procedure according to an embodiment of the present application;

fig. 8 is a flowchart of another method for acquiring timing advance in a contention-based random access procedure according to an embodiment of the present application;

fig. 9 is a flowchart for acquiring a timing advance in a satellite-to-ground communication scenario according to an embodiment of the present application;

fig. 10 is a flowchart of another method for acquiring a timing advance according to an embodiment of the present application;

fig. 11 is a flowchart of another timing advance acquisition process in a contention-based random access procedure according to an embodiment of the present application;

fig. 12 is a flowchart of acquiring a timing advance in a satellite-to-ground communication scenario according to an embodiment of the present application;

fig. 13 is a schematic diagram of transmission delay in a communication link according to an embodiment of the present application;

fig. 14 is a block diagram of a terminal according to an embodiment of the present application;

fig. 15 is a block diagram of a network device according to an embodiment of the present application;

fig. 16 is a schematic block diagram of a terminal provided in an embodiment of the present application;

fig. 17 is a schematic block diagram of a network device provided in an embodiment of the present application;

fig. 18 is a block diagram of another network device provided in the embodiment of the present application;

fig. 19 is a schematic block diagram of another terminal provided in an embodiment of the present application;

FIG. 20 is a schematic block diagram of yet another network device provided by an embodiment of the present application;

fig. 21 is a schematic block diagram of a chip system provided in an embodiment of the present application.

Detailed Description

The conventional method for acquiring the TA in the LTE system comprises the following steps: the network equipment measures the transmission delay through the preamble sequence of the PRACH of the terminal to obtain the TA value. And then feeding back a TA value to the terminal in the RAR message, and the terminal adjusts the uplink sending time of the terminal according to the TA value. If the method for acquiring the TA value in the conventional LTE system is used in the communication system in which the network element moves, the network device calculates the TA value and then transmits the TA value to the terminal after another transmission because the coverage of the network device in the communication system in which the network element moves is large. The round-trip transmission delay in the TA value acquisition process causes a large TA measurement value error, and a large TA value error causes a delay error of different terminals reaching the network device to exceed the length of one CP, resulting in that an uplink signal sent by the terminal cannot be decoded correctly. In addition, as the network element moves and the TA value changes faster, the TA value needs to be adjusted frequently, and the network device measures the TA through the uplink traffic channel and feeds the TA back to the terminal, which results in excessive signaling overhead.

In a communication system with mobile network elements, the mobile speed of the network elements is far greater than that of the network elements in the conventional LTE system, and the coverage area of the network equipment is also far greater than that of the cells in the conventional LTE system.

In the embodiment of the application, the TA value can be measured at the terminal side, and after the TA value is obtained by the terminal, the time synchronization can be carried out according to the TA value, so that the defects of large TA value measurement value error and large signaling overhead existing in the traditional method for obtaining the TA in the LTE in the communication system with mobile network elements are overcome. Compared with the conventional method for acquiring the TA value in LTE, in the method for measuring the TA value provided by this embodiment, the TA value is acquired at the terminal side, and it is not necessary for the network device to frequently measure the TA value and send a TA adjustment command, so the method of this embodiment acquires the TA value, avoids retransmission of the TA value from the network device to the terminal, and simplifies the acquisition process of the TA value.

The embodiment of the application is not only suitable for the communication scene of the mobile network element, but also suitable for the communication scene of the static network element. As shown in fig. 1, the wireless communication system includes at least one network device and at least one terminal (only one is shown), and the moving speed v of the network device₁And a moving speed v of the terminal₂Can be positive or can be zero, the moving speed v of the network device₁And a moving speed v of the terminal₂The directions may be the same or opposite. The network devices may be stationary or mobile. The terminal communicating with the network device may be stationary or may be mobile. When the network device is in a mobile state, for example, to realize network coverage in ocean or desert regions, the network device may be placed on a hot air balloon whose position is constantly moving, so as to realize large area of the network deviceAnd (4) volume coverage. The mobile network device may also be a satellite in a satellite communication system with OFDM as a modulation format. When the terminal moves, for example, in a common 3G or 4G mobile communication scene, the terminal such as a handheld device and a mobile station can move; in communication scenes that the terminals move at high speed, such as civil aviation, high-speed rail and the like, the moving speed of the terminals can be high. The wireless communication system may be a satellite communication system using OFDM as a modulation format, or may be a 4G communication system (e.g., an LTE system), a 5G communication system (e.g., a new air interface system), a communication system with a converged plurality of communication technologies (e.g., a communication system with a converged LTE technology and a new air interface technology), a subsequent evolution system, and the like.

In the embodiment of the present application, the network device with the base station processing capability may be disposed at the satellite side, that is, the embodiment may be applied to a scene in which the satellite has the onboard processing capability. The embodiment can also be applied to a bent pipe forwarding scene, wherein network equipment with base station processing capacity is arranged on the ground, sends the signal to a satellite and forwards the signal to the terminal through the satellite; the terminal can also transmit the signal to the satellite side, and the satellite forwards the signal to the network equipment with the base station processing capability on the ground. In an LTE network, the network device may be an eNode B. In the new air interface network, the network device may be a Transmission Reception Point (TRP) or a next generation node (generation node B).

In the embodiments of the present application, the terminal may be a handheld device having a wireless communication function, an in-vehicle device, a wearable device, a computing device, or other processing device connected to a wireless modem, and the like. Terminals can be called different names in different networks, for example: subscriber equipment, mobile stations, subscriber units, stations, cellular telephones, personal digital assistants, wireless modems, wireless communication devices, handheld devices, laptops, cordless telephones, wireless local loop stations, and the like.

In the solution of the embodiment of the present application, in order to obtain the TA value, the terminal may first determine a clock difference value between the terminal and the network device. Said clock difference is the difference between the clock information characterized by the timer of said terminal and the clock information characterized by the timer of said network device. The terminal may obtain the TA value according to the time information issued by the network device and the time information of the terminal, and considering a clock difference between the network device and the terminal.

Determining the acquisition of the clock difference value between the network device and the terminal, which may be as follows: and obtaining the result through two times of interaction between the network equipment and the terminal. For example, the two interaction processes of the network device and the terminal are as follows, the first interaction is as follows: the terminal records first time information of the terminal and sends the first time information to the network equipment, wherein the first time information of the terminal is clock information represented by a timer of the terminal in the first interaction process of the terminal. The network equipment records first time information of the network equipment when the first time information of the terminal is received, wherein the first time information of the network equipment is clock information represented by a timer of the network equipment in the first interaction process of the network equipment. And (4) second interaction: and the network equipment records second time information of the network equipment and sends the second time information to the terminal, wherein the second time information of the network equipment is clock information represented by a timer of the network equipment in the second interaction process of the network equipment. And the terminal records second time information when receiving the second time information of the network equipment. And determining the difference value of the clock information of the terminal and the network equipment according to the time information in the two interaction processes.

The terminal can determine the transmission delay according to the difference value of the clock information of the terminal and the clock information of the network equipment so as to determine the TA value.

The random access procedure is divided into a contention-based random access procedure and a non-contention-based random access procedure. The contention-based random access procedure is as shown in fig. 2, where a terminal randomly selects a random access preamble and sends a random access preamble message on available resources of the random access preamble; after the network device successfully detects the random access preamble message of the terminal, it will send a random access response message, where the message at least includes: a random access preamble identity, an uplink grant (UL grant), etc.; after receiving the random access response message, the terminal transmits a message (Msg) 3 on a resource designated by uplink authorization, wherein the message 3 at least comprises a request message for establishing Radio Resource Control (RRC) connection of the terminal; after receiving the message 3 sent by the terminal, the network device sends a competition resolving message carrying the terminal mark to the terminal which is successfully accessed. A random access process based on non-contention is shown in fig. 3, first, a network device selects a random access preamble, and issues the random access preamble to a terminal through a dedicated signaling; the terminal sends random access preamble information on corresponding resources based on the preamble sequence distributed by the network equipment; after the network device successfully detects the random access preamble message, it will send a random access response message. When the TA value is determined in the random access process, the time information of the network device, the location information of the network device, the time information of the terminal, and the location information of the terminal may be carried in the interactive message between the terminal and the network device in the random access process.

The first time information and the second time information of the network device and the first time information and the second time information of the terminal may be carried in a specific message in an interactive process between the terminal and the network device. Taking the non-contention based random access procedure as an example, in the non-contention based random access procedure, a difference between the first time information of the terminal and the first time information of the network device may be obtained at a network device side or a terminal side.

And determining the clock information difference between the terminal and the network equipment in the non-contention based random access process. The specific mode is as follows: when the difference value between the first time information of the terminal and the first time information of the network equipment is calculated at the network equipment side, the terminal loads the first time information of the terminal in a random access preamble message and sends the random access preamble message to the network equipment; since the network device side can obtain the difference between the first time information of the terminal and the first time information of the network device, the network device loads the difference between the first time information of the terminal and the first time information of the network device and the second time information of the network device in a random access response message and sends the random access response message to the terminal. When the difference between the first time information of the terminal and the first time information of the network equipment is calculated at the terminal side, the situation is different from the calculation difference at the network equipment side. The terminal loads the first time information of the terminal in a random access preamble message and sends the random access preamble message to the network equipment; because the network device side does not obtain the difference value between the first time information of the terminal and the first time information of the network device, the network device loads the first time information of the terminal, the first time information of the network device and the second time information of the network device in a random access response message and sends the random access response message to the terminal. And the terminal records second time information of the terminal, wherein the second time information of the terminal is the time information when the terminal receives the random access message.

And in the contention-based random access process, determining the clock information difference between the terminal and the network equipment. The specific mode is as follows: in the contention-based random access procedure, the difference between the first time information of the terminal and the first time information of the network device may be obtained at the network device side or the terminal side, as in the non-contention-based random access procedure. When the difference between the first time information of the terminal and the first time information of the network device is calculated at the network device side, the terminal may send the first time information of the terminal to the network device in a random access preamble message, or may send the first time information of the terminal to the network device in a message 3, where the message 3 may be an Msg3 message in a random access process, where the Msg3 message may include the terminal unique flag, and the flag may be used for collision resolution. Since the network device side can obtain the difference between the first time information of the terminal and the first time information of the network device, the network device loads the difference between the first time information of the terminal and the first time information of the network device and the second time information of the network device in a random access response message and sends the random access response message to the terminal. Or the network equipment loads the difference value between the first time information of the terminal and the first time information of the network equipment and the second time information of the network equipment in a competition resolving message and sends the competition resolving message to the terminal. And the terminal records second time information of the terminal, wherein the second time information of the terminal is the time information when the terminal receives the competition resolving message.

And in the contention-based random access process, determining the clock information difference between the terminal and the network equipment. The specific mode can also be as follows: when the difference between the first time information of the terminal and the first time information of the network device is calculated at the terminal side, the terminal may send the first time information of the terminal to the network device by being carried in a random access preamble message, or may send the first time information of the terminal to the network device by being carried in a message 3. At this time, the situation is different from the difference calculated by the network device side, and since the network device side does not obtain the difference between the first time information of the terminal and the first time information of the network device, the network device loads the first time information of the terminal, the first time information of the network device, and the second time information of the network device in a random access response message and sends the random access response message to the terminal. Or the network equipment loads the first time information of the terminal, the first time information of the network equipment and the second time information of the network equipment in a competition resolving message and sends the competition resolving message to the terminal. And the terminal records second time information of the terminal, wherein the second time information of the terminal is the time information when the terminal receives the competition resolving message.

On the basis of the interaction between the network equipment and the terminal, the difference value of the clock information of the network equipment and the clock information of the terminal can be obtained according to the time information of the network element in the interaction process. The terminal makes a difference between the third time information issued by the network device and the third time information of the terminal, and the difference obtained is subtracted by the difference of the clock information of the network device and the terminal, so that the transmission delay between the terminal and the network device can be obtained. The TA value may be determined according to the transmission delay, which may be twice the transmission delay.

Fig. 4 is a schematic diagram of a synchronization signal Block (SS Block) according to an embodiment of the present application. The SS Block includes a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSs), and a Physical Broadcast Channel (PBCH), and optionally, the SS Block may further include a frequency domain resource Block of clock information, where a center frequency of the frequency domain resource Block of the clock information is aligned with a center frequency of the frequency domain resource Block of the PSS, the frequency domain resource Block of the SSs, and the frequency domain resource Block of the PBCH.

The terminal can acquire the clock information of the network device through a PBCH in an SS Block sent by the network device, or the terminal acquires the clock information of the network device according to a clock information frequency domain resource Block in the SS Block sent by the network device. After the terminal acquires the clock information of the network equipment, determining the transmission delay of the network equipment and the terminal according to the clock information of the terminal when the clock information of the network equipment is acquired and the difference value of the clock information of the terminal and the clock information of the network equipment, and finally determining the TA value of the terminal. The TA value is calculated at the terminal side, so that the problem that the TA value is calculated by network equipment in the traditional LTE system and then is issued to the terminal is avoided, the transmission delay is reduced, and the measurement error of the TA value can be reduced. On the other hand, after the clock difference value between the terminal and the network device is obtained, the network device issues time information, the terminal receives the time information issued by the network device and can obtain a TA value according to the time information of the terminal, and signaling overhead is saved.

In the solution of the embodiment of the present application, in order to obtain the TA value, the terminal may first obtain position information of the terminal and ephemeris information of the network device, where the ephemeris information of the network device at least includes a motion trajectory of the network device. And the terminal determines the TA value according to the time information issued by the network equipment and the time information of the terminal.

Obtaining ephemeris information of the network device and location information of the terminal may be performed as follows: and obtaining the result through two times of interaction between the network equipment and the terminal. For example, the two interaction processes of the network device and the terminal are as follows, the first interaction is as follows: and the terminal sends a first message carrying first time information of the terminal to the network equipment. The network device records first time information of the network device and first position information of the network device when the first message is received. And (4) second interaction: the network device records second time information of the network device and second position information of the network device, and sends a second message to the terminal, wherein the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first position information of the network device and the second position information of the network device, and the second message can also carry a difference value between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first position information of the network device and the second position information of the network device. And the terminal records second time information of the terminal when the terminal receives the second message. And the terminal acquires ephemeris information of the network equipment and position information of the terminal according to the time information and the position information in the two interaction processes. Optionally, the ephemeris information of the network device may also be obtained through a broadcast message, where the broadcast message may be a Master Information Block (MIB), a System Information (SI), a remaining system information (RMSI), and the like. After the terminal acquires the ephemeris information of the network equipment and the position information of the terminal, the network equipment issues time information, and the terminal records the time information of the terminal.

The terminal can determine the transmission delay according to the ephemeris information of the network device and the position information of the terminal, and according to the time information issued by the network device and the time information of the terminal, so as to determine the TA value.

In the random access process shown in fig. 2 and fig. 3, when obtaining the ephemeris information of the network device and the location information of the terminal, the time information of the terminal, the location information of the network device, and the time information of the network device may be carried in an interaction message between the terminal and the network device in the random access process.

In the non-contention based random access procedure, the first time information of the terminal may be carried in a random access preamble message. The first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device may be carried in a random access response message, or a difference value between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device may be carried in a random access response message.

In the contention-based random access procedure, the first time information of the terminal may be carried in a random access preamble message. The first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device may be carried in a random access response message, or a difference value between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device may be carried in a random access response message. Optionally, the first time information of the terminal may be carried in message 3. The first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device may be carried in a contention resolution message, or a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device may be carried in a contention resolution message.

On the basis of the interaction between the network equipment and the terminal, ephemeris information of the network equipment and position information of the terminal can be obtained according to the time information and the position information of the network element in the interaction process. Optionally, the ephemeris information of the network device may also be acquired through a broadcast message. The terminal may further obtain the transmission delay according to the third time information of the network device and the third time information of the terminal. The TA value may be determined according to the transmission delay, and may be twice the transmission delay.

The terminal acquires the clock information of the network equipment through a PBCH in the SS Block sent by the network equipment, or the terminal acquires the clock information of the network equipment according to a clock information frequency domain resource Block in the SS Block sent by the network equipment. After the terminal acquires the clock information of the network equipment, determining the transmission delay between the network equipment and the terminal according to the position information of the terminal, the ephemeris information of the network equipment and the clock information of the terminal when the clock information of the network equipment is acquired, and finally determining the TA value of the terminal. The TA value is calculated at the terminal side, so that the problem that the TA value is calculated by network equipment and then is issued to the terminal in the traditional LTE system is avoided, the transmission delay is reduced, and the measurement error of the TA value can be reduced. On the other hand, after the clock difference value between the terminal and the network device is obtained, the network device issues time information, the terminal receives the time information issued by the network device and can obtain a TA value according to the time information of the terminal, and signaling overhead is saved.

As shown in fig. 5, an embodiment of the present application provides a method for obtaining a TA value, which may include:

according to the step 502-510, the clock information difference between the terminal and the network device can be determined.

502: the terminal sends a first message carrying first time information of the terminal to network equipment.

The first time information of the terminal is time information when the terminal sends the first message, where the first time information may be time information represented by a clock source configured by the terminal.

The time information may be clock information represented by a pseudo random sequence, the pseudo random sequence varies with time, and may represent clock information of the network device or the terminal, and the time information may also be clock information represented in a digital form. In one embodiment of the present application, the first time information may be represented by a bit sequence placed on subcarriers in an OFDM symbol.

In the contention-based random access procedure, the first message may be a random access preamble message or an Msg3 message; in the non-contention based random access procedure, the first message may be a random access preamble message.

504: the network device records first time information of the network device when the first message is received.

The first time information of the network device is the time information when the network device receives the first message. For example, the network device is at time t₁Receiving the first message, the network device records t₁Is the first time information of the network device.

506: the network device records second time information of the network device.

The second time information of the network device is time information when the network device sends a second message. And after receiving the first message, the network equipment responds to the first message, sends a second message to the terminal, and records second time information of the network equipment when the network equipment sends the second message to the terminal. For example, the network device is at time t₂Sending the second message, the network deviceRecord t₂Second time information of the network device.

In the contention-based random access procedure, the second message may be an RAR message or a contention resolution message; in the non-contention based random access procedure, the second message may be a RAR message.

508: and the network equipment sends a second message to the terminal.

When the difference value between the first time information of the network equipment and the first time information of the terminal is determined at the network equipment side, the network equipment sends a second message carrying the difference value between the first time information of the terminal and the first time information of the network equipment and second time information of the network equipment to the terminal.

When the difference value between the first time information of the network equipment and the first time information of the terminal is determined at the terminal side, the network equipment sends a second message carrying the first time information of the terminal, the first time information of the network equipment and the second time information of the network equipment to the terminal.

510: and the terminal records second time information when the terminal receives the second message of the network equipment.

For example, the terminal is at time t₃Receiving the second message, the terminal recording t₃And the second time information of the terminal. And determining the difference value of the clock information of the terminal and the network equipment according to the difference value of the first time information of the terminal and the first time information of the network equipment and the difference value of the second time information of the network equipment and the second time information of the terminal. The second time information of the terminal is the time information when the terminal receives the second message. The difference between the first time information of the terminal and the first time information of the network device and the difference between the second time information of the network device and the second time information of the terminal both include the difference between the clock information of the terminal and the clock information of the network device. Under the condition of symmetrical links, the uplink and downlink transmission time delay can be offset, and the terminal clock information can be obtainedAnd the difference to the network device clock information.

512: and the terminal receives a third message which is sent by the network equipment and bears third time information of the network equipment, determines the transmission delay between the terminal and the network equipment according to the third time information of the terminal when the third message is received, and further determines a TA value.

The third time information of the network device is time information issued by the network device for calculating the transmission delay between the network device and the terminal; the third time information of the terminal is time information issued by the network device when calculating the transmission delay between the network device and the terminal.

It should be understood that, in the method for acquiring a timing advance by a terminal and a network device according to the embodiment of the present application, the sequence numbers of the above-mentioned processes do not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not limit the implementation process of the embodiment of the present application.

Fig. 6 is a schematic diagram of a method for acquiring a timing advance according to an embodiment of the present application. In the method, in the random access process based on competition, the difference value of the first time information of the terminal and the first time information of the network equipment is calculated on the network equipment side. The method can comprise the following steps:

in the contention-based random access procedure, according to the step of 602 and 612, the clock information difference between the terminal and the network device may be determined.

602: in the interactive process of establishing random access based on competition, the terminal sends a random access preamble message carrying first time information to the network equipment.

In an interactive process of establishing random access based on contention, the terminal sends a random access preamble through a PRACH to initiate random access, and first time information of the terminal can be carried in a random access preamble message. Wherein the first time information may be time information represented by a clock source configured by the terminal.

604: in a process of random access based on contention based random access, the network device records first time information of the network device when the random access preamble message is received.

In an embodiment of the present application, in an interaction process of establishing random access based on contention, a random access preamble message is used to initiate random access, and when receiving the random access preamble message of the terminal, the network device records first time information of the network device. The difference between the first time information of the network device and the first time information of the terminal comprises a difference between clock information of the terminal and the network device.

606: the network device determines a difference value between the first time information of the network device and the first time information of the terminal.

Through the time information interaction process of step 602 and step 606, the network device obtains the first time information of the terminal, the first time information of itself, and the second time information. In an embodiment of the present application, to obtain the uplink transmission delay, the network device calculates a difference between the first time information of the network device and the first time information of the terminal. At this time, the time information stored by the network device includes: the difference value of the first time information of the network equipment and the first time information of the terminal, and the second time information of the network equipment.

608: the network device records second time information of the network device.

In an interactive process of establishing random access based on contention, the network device records second time information of the network device when sending the RAR message.

610: and in the interactive process of establishing random access based on competition, the network equipment sends the RAR message to the terminal.

In an interaction process of establishing random access based on contention, the network device may send a difference value between first time information of the terminal and first time information of the network device and second time information of the network device to the terminal through an RAR message.

612: and the terminal records second time information of the terminal when the RAR message is received and determines the difference value between the terminal clock information and the network equipment clock information.

At this time, the time information of the terminal side includes the second time information of the terminal, the second time information of the network device, and a difference value between the first time information of the network device and the first time information of the terminal, which is sent by the network device. And the terminal calculates the difference value between the second time information of the network equipment and the second time information of the terminal.

Optionally, in the contention-based random access procedure, the first time information of the terminal may be carried in the Msg3 message; the difference between the first time information of the terminal and the first time information of the network device, and the second time information of the network device may be carried in a contention resolution message.

In order to obtain the TA value of the terminal, the difference between the clock information of the terminal and the clock information of the network device needs to be determined first. The difference between the first time information of the network device and the first time information of the terminal, and the difference between the second time information of the network device and the second time information of the terminal include a clock information difference between the terminal and the network device, a transmission delay, a device processing delay and other time error factors. In the following, a processing method for transmission delay, device processing delay, and other time error factors in an embodiment of the present application is given, and finally, a method for obtaining a difference between clock information of the terminal and the network device from a first time information difference between the terminal and the network device and a second time information difference between the terminal and the network device is given.

In an embodiment of the present application, the first time information of the terminal may be denoted as T_A1The first time information of the network device may be denoted as T_B1The second time information of the network device can be denoted as T_B2The second time information of the terminal can be recorded as T_A2The network deviceThe difference value TIC (A) between the first time information and the first time information of the terminal is expressed as

TIC(A)＝T_B1-T_A1 (1)

Second time information T of the network device_A2And second time information T of the terminal_B2Is expressed as

TIC(B)＝T_A2-T_B2 (2)

Optionally, as shown in fig. 7, tic (a) and tic (b) include other time errors such as a difference between clock information of the terminal and the network device, an actual transmission delay, and a device processing delay. The error of the clock information of the terminal relative to the standard time is recorded as delta t_AAnd the error of the clock information of the network equipment relative to the standard time is recorded as delta t_B. Wherein the standard time may for example refer to the atomic time determined by a cesium atomic clock. The actual uplink and downlink transmission time delay is recorded as tau_AB、τ_BAAnd the processing time delay of the receiving and sending equipment of the network equipment is recorded as tau_BR、τ_BTAnd the processing time delay of the receiving and sending equipment of the terminal is recorded as tau_AR、τ_AT，r_A、r_BRespectively, other additional transmission delays (e.g., waveguide propagation delay) in uplink and downlink transmissions. Delta_A、δ_BRespectively, the time error of relativistic effect in the uplink and downlink transmission process. The expressions of TIC (A) and TIC (B) can be obtained as

TIC(A)＝Δt_A-Δt_B+τ_BA+τ_BT+τ_AR+r_A+δ_B (3)

TIC(B)＝Δt_B-Δt_A+τ_AB+τ_AT+τ_BR+r_B+δ_A (4)

(3) And (4) in combination, obtaining an expression of the difference between the clock information of the terminal and the clock information of the network equipment

In one embodiment of the present application, the device processing latency may be calibrated; under the condition that the uplink and downlink transmission links are symmetrical, the uplink and downlink transmission time delay and the additional time delay can be offset; the relativistic effect at small scale is negligible; the difference between the clock information of the terminal and the network device can be easily obtained from the above equation.

It should be understood that the transmission delay and other time error factors included in tic (a), tic (b) are not limited to the foregoing embodiment, and this embodiment does not make any limitation on the processing manner of various transmission delays and time errors in the uplink and downlink transmission process between the terminal and the network device.

614: and the terminal receives a third message which is sent by the network equipment and bears third time information of the network equipment, and determines transmission delay according to the third time information of the terminal when the third message is received so as to determine a TA value.

In an embodiment of the present application, the third message sent by the network device may include SS Block, where the SS Block includes PBCH. The terminal may obtain the third time information of the network device according to the system frame number carried by the PBCH in the SS Block and the subframe number or timeslot number in which the PBCH is located. Optionally, the SS Block may include a clock information frequency domain resource Block, and the terminal may further obtain the clock information of the network device through the clock information frequency domain resource Block in the SS Block.

The third time information of the network device may be carried in a Physical Resource Block (PRB). And the terminal obtains the third time information of the network equipment according to the system frame number carried by the PBCH in the SS Block and the subframe number or the time slot number of the PBCH. And the terminal obtains the TA value according to the time information when the terminal receives the SS Block. Compared with the method for acquiring the TA value in the traditional LTE, the method for acquiring the TA value in the embodiment of the application saves signaling overhead. It can be understood that the length of the interval between two adjacent times of sending the third time information of the network device and the length of the time information in the SS Block may be different values according to different wireless communication systems, which is not limited in this embodiment of the present application.

The third time information of the network device in the third message is recorded as T_BdThe third time information of the terminal receiving the third message of the network device is marked as T_AdThe transmission delay between the terminal and the network device can be obtained as

τ＝T_Ad-T_Bd-(Δt_A-Δt_B) (6) the terminal may determine a TA value according to the transmission delay, where the TA value is twice the transmission delay, and an expression of the TA is

TA＝2τ＝2T_Ad-2T_Bd-2(Δt_A-Δt_B) And (7) adjusting the sending time of the uplink signal according to the received signal, and realizing uplink synchronization. The TA value may be determined in other manners, and the embodiment of the present application is not limited.

In the above embodiment, the time information is obtained through the interaction between the network device and the terminal, and the TA value is determined at the terminal side according to the difference between the time information. On one hand, the TA value is obtained at the terminal side and then is locally used, so that compared with the mode of obtaining the TA value in the traditional LTE system, the round-trip transmission that the network equipment obtains the TA value and then sends the TA value to the terminal is avoided, the transmission delay is small, and the error of the TA measurement value is reduced.

In a conventional LTE system, a network device measures transmission delay through a preamble sequence of a physical random access channel PRACH of a terminal to obtain a TA value. And then feeding back a TA value to the terminal in a Random Access Response (RAR) message, and adjusting the uplink sending time of the terminal according to the TA value by the terminal. The network device periodically measures a TA value from the uplink traffic channel and then gives a TA adjustment command in the downlink control channel. In the embodiment of the present application, the terminal may determine the clock difference between the terminal and the network device according to the third time information sent by the network device and the third time information of the terminal, so as to obtain the TA value of the terminal, thereby saving signaling overhead.

Fig. 7 is a schematic diagram of a method for acquiring a timing advance according to an embodiment of the present application. In the method, in a random access process based on non-competition, the difference value of first time information of a terminal and network equipment is calculated on the network equipment side. The method can comprise the following steps:

in the non-contention based random access procedure, according to the step of 702 and 712, the clock information difference between the terminal and the network device may be determined.

702: and the terminal sends the random access preamble message carrying the first time information to the network equipment.

In the non-contention based random access process, the terminal sends a random access preamble through the PRACH to initiate random access. The first time information of the terminal may be carried in a random access preamble message.

704: and the network equipment records the first time information of the network equipment when the random access preamble message is received.

The random access preamble message is used for requesting to establish random access, and the network equipment records first time information of the network equipment when receiving the random access preamble message of the terminal. The difference between the first time information of the network device and the first time information of the terminal comprises a difference between clock information of the terminal and the network device.

706: the network device determines a difference value between the first time information of the network device and the first time information of the terminal.

708: the network device records second time information of the network device.

And after receiving the random access preamble message, the network equipment sends an RAR message to the terminal. And the network equipment records second time information of the network equipment when the RAR message is sent.

Through the time information interaction process of

step

702 and 708, the network device obtains the first time information of the terminal, the first time information of the network device, and the second time information of the network device. In an embodiment of the present application, the network device calculates a difference between the first time information of the network device and the first time information of the terminal. At this time, the time information of the network device side includes: the difference value of the first time information of the network equipment and the first time information of the terminal, and the second time information of the network equipment.

710: and the network equipment sends the RAR message carrying the difference value between the first time information of the terminal and the first time information of the network equipment and the second time information of the network equipment to the terminal.

712: and the terminal records second time information when the terminal receives the RAR message of the network equipment, and determines the difference value between the second time information of the network equipment and the second time information of the terminal so as to determine the difference value between the clock information of the terminal and the clock information of the network equipment.

714: and the terminal receives a third message which is sent by the network equipment and bears third time information of the network equipment, and determines a TA value according to the third time information of the terminal when the third message is received.

The specific implementation of obtaining the TA value may refer to the description related to

steps

612 and 614 in the embodiment described in fig. 6, and is not described herein again.

In this embodiment, because on the terminal side, the terminal may obtain the third time information of the network device according to the system frame number carried by the PBCH in the SS Block and the subframe number or timeslot number in which the PBCH is located. And the terminal obtains the TA value according to the time information when the terminal receives the SS Block. Compared with the traditional method for acquiring the TA value in LTE, the method for acquiring the TA value saves signaling overhead because the network equipment measures the transmission delay through the preamble sequence of the PRACH of the terminal to obtain the TA value and feeds the TA value back to the terminal, or the network equipment measures the TA value from the uplink service channel and then sends the TA adjusting command in the downlink control channel. In the embodiment of the application, the TA value is obtained at the terminal side, so that the problem that the TA value is calculated by network equipment and then is issued to the terminal in the traditional LTE system is avoided, the transmission delay is reduced, and the measurement error of the TA value can be reduced.

Fig. 8 is a schematic diagram of a method for acquiring a timing advance according to an embodiment of the present application. In the method, the difference between the first time information of the terminal and the first time information of the network device can be determined at the terminal side. The method can comprise the following steps:

in the contention-based random access procedure, according to the step of 802 and 810, the clock information difference between the terminal and the network device may be determined.

802: in the interactive process of establishing random access based on competition, the terminal sends a random access preamble message carrying first time information to the network equipment.

804: in an interactive process of establishing random access based on competition, the network equipment records first time information of the network equipment when the random access preamble message is received.

806: the network device records second time information of the network device.

808: in an interactive process of contention-based random access establishment, the network device may send a RAR message to the terminal.

For specific implementation of

steps

802, 804, 806, and 808, reference may be made to the description related to

steps

602, 604, 608, and 610 in the embodiment described in fig. 6, and details thereof are not repeated here.

In this embodiment of the present application, since a difference between the first time information of the network device and the first time information of the terminal is calculated on a terminal side, the RAR message of the network device includes the first time information of the network device, the second time information of the network device, and the first time information of the terminal.

810: in the interactive process of establishing random access based on competition, the terminal receives an RAR message issued by the network equipment, and records second time information when the terminal receives the RAR message of the network equipment so as to determine the difference value between the terminal clock information and the network equipment clock information.

Optionally, in a contention-based random access procedure, the first time information of the terminal may be carried in the Msg3 message; the first time information of the terminal, the first time information of the network device, and the second time information of the network device may be carried in a contention resolution message.

In the application embodiment, the terminal determines a difference value between first time information of the terminal and first time information of the network device, and a difference value between second time information of the terminal and second time information of the network device, so as to determine a difference value between clock information of the terminal and the network device. The first time information and the second time information of the terminal may be respectively denoted as T_A1、T_A2The first time information and the second time information of the network device may be respectively denoted as T_B1、T_B2. Since the difference between the first time information and the second time information of the terminal and the network device includes the difference between the clock information of the terminal and the clock information of the network device, the terminal first needs to calculate the difference between the first time information of the terminal and the network device and the difference between the second time information of the terminal and the network device,

TIC(A)＝T_B1-T_A1 (8)

TIC(B)＝T_B2-T_A2 (9)

the difference between the clock information of the terminal and the network device is obtained according to the algorithm described in step 612 of the embodiment of fig. 6.

812: and the terminal receives a third message which is sent by the network equipment and bears third time information of the network equipment, and determines a TA value.

The terminal receives a third message that is delivered by the network device and carries third time information of the network device, and determines a transmission delay between the terminal and the network device according to the third time information of the terminal when the terminal receives the third message, so as to determine a TA value, which may be specifically implemented with reference to the relevant description in step 614, and details are not repeated here.

In the embodiment of the application, the calculation of the difference value between the first time information of the terminal and the first time information of the network equipment is completed on the terminal side. The calculation process of the time information comprises the calculation of the difference value of the first time information of the terminal and the first time information of the network equipment, the calculation of the difference value of the second time information and the second time information of the network equipment, the calculation of the difference value of the clock information of the terminal and the network equipment, the calculation of the transmission delay and the calculation of the TA value, which are all completed at the terminal side. The terminal independently finishes all calculation processes, and a module for determining the difference value between the first time information of the terminal and the first time information of the network equipment is not configured in the network equipment, so the structural complexity of the network equipment can be simplified.

Fig. 9 is a schematic diagram of a method for acquiring a TA value in a satellite communication system according to an embodiment of the present application, where a network element involved in the satellite communication system includes a terminal, a network device installed on a satellite, or a satellite ground station for relaying a signal thereof by the satellite. In the satellite communication system, the process of acquiring TA values presents different characteristics from those of a terrestrial mobile communication system: firstly, because the signal coverage range of a satellite is far larger than that of a ground cell, the absolute distance between the satellite and a ground terminal is far larger than the distance between network equipment and the terminal in a ground mobile communication system, and the difference value between the nearest distance and the farthest distance between different terminals and the satellite is also far larger than the maximum distance difference in an LTE ground cellular communication cell, the value range of the TA value is large; secondly, in the satellite communication system, the satellite moves fast relative to the terminal, and the change speed of the distance between the satellite and the terminal is also larger than that between the network equipment and the terminal in the ground mobile communication system. These two characteristics lead to the fact that in the satellite communication system, the TA value acquisition method needs to be particularly concerned.

In the satellite communication system, the method for acquiring the TA value by using the ofdm modulation scheme may include:

in accordance with 902-.

902: the terminal sends a first message carrying first time information of the terminal to a satellite.

904: the satellite records first time information of the satellite at the time of receiving the first message.

In the satellite communication system, the coverage of a satellite is large, and the distance between the satellite and the terminal is changed quickly. For example, in a satellite communication system with a coverage radius of 422km and a coverage area of 56 kilometres square (track height of 780km), when the elevation angle of the satellite ranges from 90 degrees to 58.2 degrees, the distance between the terminal and the satellite ranges from 780km to 899km, and the range of the satellite movement exceeds 100 km. In the conventional terrestrial mobile communication system, the information bit length indicating the TA value is not sufficient to indicate the transmission delay in the satellite communication system. In this embodiment, by recording the first time information of the terminal and the first time information of the satellite, the transmission delay in the process of receiving and sending the first message may be represented by a difference between the first time information of the terminal and the first time information of the satellite.

906: the satellite records second time information of the satellite.

And after receiving the first message, the satellite responds to the first message, sends a second message to the terminal and records second time information when the satellite sends the second message to the terminal.

For specific implementation of

steps

902, 904, and 906, reference may be made to

steps

502, 504, and 506 in the embodiment illustrated in fig. 5 and related descriptions of

steps

602, 604, and 606 in the embodiment illustrated in fig. 6, which are not described herein again.

908: the satellite transmits a second message to the terminal.

The satellite sends a second message carrying first time information of the terminal, the first time information of the satellite and second time information of the satellite to the terminal, or the satellite sends a second message carrying a difference value between the first time information of the terminal and the first time information of the satellite and the second time information of the satellite to the terminal.

910: and the terminal records second time information when the terminal receives the second satellite message, and determines the difference value between the terminal clock information and the satellite clock information according to the difference value between the first time information of the terminal, the first time information of the satellite, the second time information of the satellite and the second time information of the terminal.

In the satellite communication system, a difference between the second time information of the satellite and the second time information of the terminal may represent a transmission delay.

912: and the terminal receives a third message which is transmitted by the satellite and bears the third time information of the satellite, and determines the TA value according to the third time information of the terminal when receiving the third message.

And assuming that the time delay change rate is 25us/s at the fastest speed and the length of the short CP is 4.6875us, when the TA value is acquired at the terminal, and the updating period of the TA value is less than 93.75ms, the error of the TA is less than 4.6875 us. Therefore, the method for acquiring the TA value in the embodiment of the application can enable the error of the TA measurement value to be within one CP length, thereby ensuring that the uplink signal of the terminal can be correctly decoded.

The method for determining the clock information difference and the TA value between the satellite and the terminal may refer to the related descriptions in the steps of the foregoing

embodiments

612 and 614, and details are not repeated here.

In a satellite-ground communication scene, the TA value is determined at the terminal side, so that the round-trip transmission that the TA value is acquired by the satellite and then sent to the terminal is avoided, the transmission delay is small, and the error of the TA measurement value is reduced.

And the terminal acquires the clock information of the satellite through the PBCH in the SS Block sent by the satellite. Optionally, the terminal may obtain the clock information of the satellite through a clock information frequency resource Block in an SS Block sent by the satellite. The issuing period of the SS Block of the satellite can be 5ms, and the terminal continuously adjusts uplink timing by taking 5ms as the period, so that the accuracy of timing synchronization can be improved. The terminal can continuously adjust the TA value of the terminal according to the time information continuously issued by the satellite and the time information of the terminal, so that the signaling overhead is saved.

In the solution of the embodiment of the present application, in order to obtain a TA value, a terminal may further determine location information of the terminal and ephemeris information of a network device first, and after obtaining the location information of the terminal and the ephemeris information of the network device, the terminal finally determines a transmission delay and a time advance according to time information issued by the network device, the time information of the terminal, and the ephemeris information of a satellite, where the ephemeris information of the network device at least includes a motion trajectory of the network device. It should be noted that for the bent-tube retransmission scenario, i.e., the scenario in which the satellite retransmits a signal, the ground station is stationary, and in this scenario, ephemeris information of the moving satellite is acquired.

Determining the position information of the terminal and the ephemeris information of the network device may be performed as follows: and obtaining the result through two times of interaction between the network equipment and the terminal. For example, the two interaction processes of the network device and the terminal are as follows, the first interaction is as follows: the terminal records first time information of the terminal and sends a first message carrying the first time information of the terminal to the network equipment, wherein the first time information of the terminal is clock information represented by a timer of the terminal when the terminal sends the first message. The network device records first time information of the network device and first position information of the network device when the first message is received. And (4) second interaction: the network equipment records second time information of the network equipment and second position information of the network equipment, and sends a second message carrying the first time information of the network equipment, the first position information of the network equipment, the second time information of the network equipment and the second position information of the network equipment to the terminal, the second time information and the second position information of the network equipment are clock information of the network equipment and the position information of the network equipment when the network equipment sends the second message, and the terminal records the second time information of the terminal when the terminal receives the second message. And the terminal acquires the position information of the terminal and the ephemeris information of the network equipment according to two interactive processes of the time information and the position information. Optionally, the ephemeris information of the network device may also be acquired through a broadcast message.

The first time information of the network device, the second time information of the network device, the first location information of the network device, the second location information of the network device, the first time information of the terminal, and the second time information of the terminal may be carried in a specific message during an interaction process between the terminal and the network device.

And in the non-contention based random access process, determining the position information of the terminal and the ephemeris information of the network equipment. The specific mode is as follows: the terminal loads the first time information of the terminal in a random access preamble message and sends the random access preamble message to the network equipment; and the network equipment loads the first time information of the terminal, the first time information of the network equipment, the first position information of the network equipment, the second time information of the network equipment and the second position information of the network equipment in a random access response message and sends the random access response message to the terminal.

And in the contention-based random access process, determining the position information of the terminal and the ephemeris information of the network equipment. The specific mode is as follows: the terminal loads the first time information of the terminal in a random access preamble message or a message (Msg) 3 and sends the message to the network equipment; and the network equipment loads the first time information of the terminal, the first time information of the network equipment, the first position information of the network equipment, the second time information of the network equipment and the second position information of the network equipment in a random access response message or a competition resolving message and sends the random access response message or the competition resolving message to the terminal.

After obtaining the position information of the terminal and the ephemeris information of the network device, the terminal receives a third message issued by the network device, where the third message carries third time information of the network device, or the third message also carries third position information of the network device. The terminal may determine a transmission delay according to third time information of the terminal and the third time information of the network device to determine a TA value, where the third time information of the network device is time information when the network device sends the third message, and the third time information of the terminal is time information when the terminal receives the third message. And the terminal acquires the clock information of the network equipment through PBCH in SS Block sent by the network equipment. Optionally, the terminal may obtain the clock information of the network device through a clock information frequency domain resource Block in the SS Block sent by the network device. After the terminal acquires the clock information of the network equipment, determining the transmission delay between the network equipment and the terminal according to the position information of the terminal, the ephemeris information of the network equipment and the clock information of the terminal when the clock information of the network equipment is acquired, and finally determining the TA value of the terminal. The TA value is calculated at the terminal side, so that the problem that the TA value is calculated by network equipment in the traditional LTE system and then is issued to the terminal is avoided, the transmission delay is reduced, and the measurement error of the TA value can be reduced. And when the TA value is determined, the position information of the terminal, the position information of the network equipment and the ephemeris information of the network equipment are also taken into account, so that the error of the TA value is further reduced. On the other hand, after the position information of the terminal and the ephemeris information of the network equipment are obtained, the network equipment issues time information, the terminal receives the time information issued by the network equipment and can obtain a TA value according to the time information of the terminal, and signaling overhead is saved.

As shown in fig. 10, an embodiment of the present application provides a method for obtaining a TA value, which may include:

according to the steps of 1002-1010, the position information of the terminal and the ephemeris information of the network device may be obtained.

1002: the terminal sends a first message carrying first time information of the terminal to network equipment.

And the first time information of the terminal is the time information when the terminal sends the first message, and the first time information of the terminal is recorded.

For details of step 1002, reference may be made to step 502 shown in fig. 5, which is not described herein again.

1004: the network device records first time information of the network device and first position information of the network device when the first message is received.

The first time information of the network device is time information when the network device receives a first message, and the first position information of the network device is position information when the network device receives the first message. For example, the network device is at time t₁Receiving the first message, the network device records t₁As first time information of the network device, the network device is at time t₁The location information of (a) is first location information of the network device.

1006: the network device records second time information of the network device and second position information of the network device.

The second time information of the network device is time information when the network device sends a second message, and the second location information of the network device is location information when the network device sends the second message. After the network equipment receives the first message, responding to the first message, sending a second message to the terminal, and recording the second message sent by the network equipment to the terminalSecond time information and second location information of the network device. For example, the network device is at time t₂Sending the second message, the network device recording t₂Is the second time information of the network equipment, the network equipment is at the time t₂Is second location information of the network device.

1008: and the network equipment sends a second message to the terminal.

The second message carries first time information of the network device, second time information of the network device, first time information of the terminal, first position information of the network device and second position information of the network device. Optionally, the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device.

1010: and the terminal acquires the position information of the terminal and the ephemeris information of the network equipment.

The terminal records second time information when the terminal receives the second message of the network device, the terminal obtains the position information of the terminal and the ephemeris information of the network device according to the first time information of the terminal, the second time information of the terminal, the first time information of the network device, the first position information of the network device, the second time information of the network device and the second position information of the network device, and the ephemeris information of the network device at least comprises a moving track of the network device. Optionally, the terminal obtains the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the terminal and the first time information of the network device, the second time information of the terminal, the first location information of the network device, the second time information of the network device, and the second location information of the network device. Optionally, the ephemeris information of the network device may also be acquired through a broadcast message. And the terminal stores the position information of the terminal and the ephemeris information of the network equipment.

1012: and the terminal receives a third message which is sent by the network equipment and bears third time information of the network equipment, determines the transmission delay between the terminal and the network equipment according to the third time information of the terminal when the third message is received, the position information of the terminal and the ephemeris information of the network equipment, and further determines the TA value.

The third time information of the network equipment is time information for calculating the transmission delay between the network equipment and the terminal and issuing the third message by the network equipment; and the third time information of the terminal is time information when the terminal receives the third message by calculating the transmission time delay of the network equipment and the terminal. After the terminal acquires the position information of the terminal and the ephemeris information of the network equipment, the terminal determines transmission delay according to the position information of the terminal, the ephemeris information of the network equipment, the third time information of the terminal and the third time information of the network equipment, and further determines time advance.

The terminal determines the transmission delay, and may determine the location information of the network device when the signal reaches the network device based on the location information of the terminal, the location information of the network device, and the ephemeris information of the network device. And the terminal determines the transmission delay according to the position information of the terminal and the position information of the network equipment when the signal reaches the network equipment, and further determines the time advance.

Fig. 11 is a schematic diagram of a method for acquiring a timing advance according to an embodiment of the present application. In the method, in a contention-based random access procedure, the method may include:

in the contention-based random access procedure, according to the

step

1102 and 1110, the location information of the terminal and the ephemeris information of the network device may be obtained.

1102: in the interactive process of establishing random access based on competition, the terminal sends a random access preamble message carrying first time information of the terminal to network equipment.

For details of step 1102, reference may be made to step 602 shown in fig. 6, which is not described herein again.

1104: in the process of contention-based random access, the network device records first time information of the network device and first position information of the network device when the random access preamble message is received.

In an embodiment of the present application, in an interaction process of establishing random access based on contention, a random access preamble message is used to initiate random access, and when receiving the random access preamble message of the terminal, the network device records first time information of the network device and first location information of the network device.

1106: the network device records second time information of the network device and second position information of the network device.

The network device records second time information of the network device and second position information of the network device when the network device sends the RAR message.

1108: and the network equipment sends the RAR message to the terminal.

The RAR message includes first time information of the terminal, first time information of the network device, first location information of the network device, second time information of the network device, and second location information of the network device. Optionally, the RAR message includes a difference between the first time information of the terminal and the first time information of the network device, the first location information of the network device, the second time information of the network device, and the second location information of the network device.

In the contention-based random access procedure, the first time information of the terminal may be carried in the Msg3 message. The first time information of the terminal, the first time information of the network device, the first location information of the network device, the second time information of the network device, and the second location information of the network device may be carried in a contention resolution message. Optionally, the difference between the first time information of the terminal and the first time information of the network device, the first location information of the network device, the second time information of the network device, and the second location information of the network device may be carried in a contention resolution message.

1110: and the terminal acquires the position information of the terminal and the ephemeris information of the network equipment.

The terminal records second time information of the terminal when the terminal receives an RAR message or a competition resolving message, and the terminal acquires the position information of the terminal and ephemeris information of the network equipment according to the first time information of the terminal, the second time information of the terminal, the first time information of the network equipment, the first position information of the network equipment, the second time information of the network equipment and the second position information of the network equipment. Optionally, the terminal obtains the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the terminal and the first time information of the network device, the second time information of the terminal, the first location information of the network device, the second time information of the network device, and the second location information of the network device. Optionally, the ephemeris information of the network device may also be acquired through a broadcast message. And the terminal stores the position information of the terminal and the ephemeris information of the network equipment.

1112: and the terminal receives a third message sent by the network equipment, and determines transmission delay and time advance according to third time information of the terminal, the third time information of the network equipment, the position information of the terminal and ephemeris information of the network equipment.

In an embodiment of the present application, the third message sent by the network device may include SS Block, where SS Block includes PBCH. The terminal may obtain the third time information of the network device according to the system frame number carried by the PBCH in the SS Block and the subframe number or timeslot number in which the PBCH is located. Optionally, the SS Block may include a clock information frequency domain resource Block, and the terminal may further obtain the clock information of the network device through the clock information frequency domain resource Block in the SS Block.

The third time information of the network device may be carried in a PRB. The terminal may obtain the third time information of the network device according to the system frame number carried by the PBCH in the SS Block and the subframe number or timeslot number in which the PBCH is located. And the terminal obtains the TA value according to the time information when the terminal receives the SS Block. Compared with the method for acquiring the TA value in the traditional LTE, the method for acquiring the TA value in the embodiment of the application saves signaling overhead. It can be understood that the length of the interval between two adjacent times of sending the third time information of the network device and the length of the time information in the SS Block may be different values according to different wireless communication systems, which is not limited in this embodiment of the present application.

In an embodiment of the present application, the terminal may determine the transmission delay according to the location information of the terminal, the ephemeris information of the network device, and the location information of the network device when the signal arrives at the network device, so as to determine the time advance.

In the above embodiment, the position information of the terminal and the ephemeris information of the network device are obtained through the interaction between the network device and the terminal, and the TA value is determined at the terminal side. On one hand, the TA value is obtained at the terminal side and then is locally used, so that compared with the mode of obtaining the TA value in the traditional LTE system, the round-trip transmission that the network equipment obtains the TA value and then sends the TA value to the terminal is avoided, the transmission time delay is small, and the error of the TA measurement value is reduced; on the other hand, in the process of acquiring the TA value, the position information of the terminal, the position information of the network device, and the ephemeris information of the network device are also taken into consideration, so that the error of the TA value is further reduced.

In a conventional LTE system, a network device measures transmission delay through a preamble sequence of a PRACH of a terminal to obtain a TA value. And then feeding back a TA value to the terminal in a Random Access Response (RAR) message, and adjusting the uplink sending time of the terminal according to the TA value by the terminal. The network device periodically measures a TA value from the uplink traffic channel and then gives a TA adjustment command in the downlink control channel. In the embodiment of the present application, after the clock information difference between the network device and the terminal is obtained, the terminal may determine the clock difference between the terminal and the network device according to the third time information sent by the network device and the third time information of the terminal, so as to obtain the TA value of the terminal, thereby saving signaling overhead.

The method for acquiring the timing advance shown in fig. 11 is also applicable to the non-contention based random access procedure. The method can comprise the following steps:

in the non-contention based random access procedure, according to the

step

1102: and the terminal sends the random access preamble message carrying the first time information of the terminal to network equipment.

1104: the network device records first time information of the network device and first position information of the network device.

1108: and the network equipment sends the RAR message to the terminal.

1110: and the terminal records second time information of the terminal when the terminal receives the RAR message, and the terminal acquires and stores the position information of the terminal and the ephemeris information of the network equipment.

1112: and after the terminal obtains the position information of the terminal and the ephemeris information of the network equipment, the terminal receives a third message of the network equipment, and the terminal determines the time advance according to the position information of the terminal, the ephemeris information of the network equipment, the third time information of the terminal and the third time information of the network equipment.

In a satellite communication system using an orthogonal frequency division multiplexing modulation scheme, a method for acquiring a TA value needs to be particularly focused. The method for obtaining the TA value is shown in fig. 12, and may include:

in accordance with 1202-1210, the position information of the terminal and the ephemeris information of the satellite may be obtained.

1202: the terminal sends a first message carrying first time information of the terminal to a satellite.

1204: the satellite records first time information of the satellite and first position information of the satellite when the first message is received.

1206: the satellite records second time information of the satellite and second position information of the satellite.

And after receiving the first message, the satellite responds to the first message, sends a second message to the terminal, and records second time information of the satellite and second position information of the satellite when the satellite sends the second message to the terminal.

For specific implementation of

steps

1202, 1204, and 1206, reference may be made to

steps

1002, 1004, and 1006 in the embodiment described in fig. 10 and related descriptions of

steps

1102, 1104, and 1106 in the embodiment described in fig. 11, and details are not repeated here.

1208: the satellite transmits a second message to the terminal.

The second message includes first time information of the terminal, first time information of the satellite, first position information of the satellite, second time information of the satellite, and second position information of the satellite. Optionally, the second message includes a difference between the first time information of the terminal and the first time information of the satellite, the first position information of the satellite, the second time information of the satellite, and the second position information of the satellite. And the terminal records second time information of the terminal when the terminal receives the second message.

1210: and the terminal acquires the position information of the terminal and the ephemeris information of the satellite according to the first time information of the terminal, the second time information of the terminal, the first time information of the satellite, the first position information of the satellite, the second time information of the satellite and the second position information of the satellite.

Optionally, the terminal obtains the position information of the terminal and the ephemeris information of the satellite according to a difference between the first time information of the terminal and the first time information of the satellite, the second time information of the terminal, the first position information of the satellite, the second time information of the satellite, and the second position information of the satellite. The terminal stores position information of the terminal and ephemeris information of the satellite.

The method for obtaining the position information of the terminal and the ephemeris information of the satellite may refer to the related descriptions in the steps of

embodiments

1010 and 1110, which are not described herein again.

1212: and the terminal receives a third message which is transmitted by the satellite and bears third time information of the satellite, determines transmission delay according to the third time information of the terminal, the third time information of the satellite, the position information of the terminal and the ephemeris information of the satellite when the third message is received, and further determines the time advance.

The method for determining the clock information difference and the TA value between the satellite and the terminal may refer to the related descriptions in the

steps

1012 and 1112 in the foregoing embodiments, and details are not repeated here.

Fig. 14 shows an apparatus diagram of the terminal in the embodiment of the present application, including a transmitter 1402, a receiver 1403, and a processor 1405.

A transmitter 1402, configured to send a first message carrying first time information of a terminal to a network device;

the first time information of the terminal is time information when the terminal sends the first message, optionally, the terminal may include a timer 1401, and the recorder 1401 is configured to record the first time information of the terminal. In the contention-based random access procedure, the transmitter 1402 is configured to send a random access preamble message or Msg3 message carrying first time information of the terminal to the network device; in the non-contention based random access procedure, the transmitter 1402 is configured to transmit a random access preamble message carrying first time information of the terminal to the network device.

In a scenario where the difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side, the receiver 1403 is configured to receive a second message that is sent by the network device and carries the difference between the first time information of the terminal and the first time information of the network device and the second time information of the network device, where the first time information of the network device is time information when the network device receives the first message.

In a scenario where a difference between the first time information of the terminal and the first time information of the network device is obtained at a terminal side, the receiver 1403 is configured to receive a second message that is sent by the network device and carries the first time information of the terminal, the first time information of the network device, and the second time information of the network device, where the second time information of the network device is time information when the network device sends the second message.

In the contention-based random access procedure, the receiver 1403 is configured to receive a RAR message or a contention resolution message of the network device; the receiver 1403 is configured to receive a RAR message of the network device in a non-contention based random access procedure.

The receiver 1403 may be further configured to receive a third message carrying third time information of the network device, where the third time information of the network device is time information when the network device sends the third message.

All or portions of the timer 1401, the transmitter 1402, and the receiver 1403 may be implemented on one or more analog circuits (ICs), radio frequency ICs, mixed signal ICs, and the like.

Optionally, the terminal may include a memory 1404, and the memory 1404 is configured to store a clock information difference between the network device and the terminal, and a transmission delay between the terminal and the network device, which are required for determining the TA value.

The memory 1404 is configured to store a difference between second time information of the terminal and second time information of the network device in a scenario where the difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side.

Under a scenario that a difference between the first time information of the terminal and the first time information of the network device is obtained at a terminal side, the memory 1404 is configured to store a difference between the first time information of the terminal and the first time information of the network device, and a difference between the second time information of the terminal and the second time information of the network device, where the second time information of the terminal is time information when the terminal receives the second message, and the timer 1401 records the second time information of the terminal.

And after the clock difference value between the terminal and the network equipment is determined according to the first time information of the terminal, the first time information of the network equipment, the second time information of the terminal and the second time information of the network equipment, the clock difference value between the terminal and the network equipment is stored.

The processor 1405 is configured to further determine, according to the time information, a clock difference value, a transmission delay, and a TA value between the terminal and the network device.

In a scenario where a difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side, the processor 1405 is configured to calculate a difference between the second time information of the terminal and the second time information of the network device.

In a scenario where the difference between the first time information of the terminal and the first time information of the network device is obtained at the network device side, the processor 1405 is further configured to calculate a clock difference between the terminal and the network device according to the difference between the first time information of the terminal and the first time information of the network device, and the difference between the second time information of the terminal and the second time information of the network device.

In a scenario where a difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side, the processor 1405 is further configured to obtain a transmission delay between the terminal and the network device according to third time information issued by the network device, the third time information of the terminal, and a clock difference between the terminal and the network device, and determine a TA value according to the transmission delay.

Under a scenario that a difference between the first time information of the terminal and the first time information of the network device is obtained at a terminal side, the processor 1405 is configured to calculate a difference between the second time information of the terminal and the second time information of the network device, and a difference between the first time information of the terminal and the first time information of the network device.

Under a scenario that a difference between the first time information of the terminal and the first time information of the network device is obtained at a terminal side, the processor 1405 is further configured to calculate a clock difference between the terminal and the network device according to the difference between the first time information of the terminal and the first time information of the network device and the difference between the second time information of the terminal and the second time information of the network device.

Under the scenario that the difference between the first time information of the terminal and the first time information of the network device is obtained at the terminal side, the processor 1405 is further configured to obtain the transmission delay between the terminal and the network device according to the third time information issued by the network device, the third time information of the terminal, and the clock difference between the terminal and the network device, and determine a TA value by the transmission delay, where the third time information of the network device is the time information when the network device sends the third message, the third message includes the third time information of the network device, and the third time information of the terminal is the time information when the terminal receives the third message. Optionally, the terminal may include a timer 1401, and the timer 1401 records third time information of the terminal.

Optionally, the terminal can include a memory 1404, the memory 1404 can store program codes and data for use by the processor 1405. The processor 1405 may be implemented on one or more Application Specific Integrated Circuits (ASICs) and/or other ICs.

In the contention-based random access procedure, the first message may be a random access preamble message or Msg3 message, and the second message may be a RAR message or a contention resolution message; in the non-contention based random access procedure, the first message may be a random access preamble message and the second message may be a RAR message.

In an embodiment of the apparatus of the terminal, the recording of the first time information and the second time information of the terminal, the calculation and storage of the difference between the first time information of the terminal and the first time information of the network device, and the calculation and storage of the difference between the second time information of the terminal and the second time information of the network device may refer to the steps of the method embodiment, and details of the obtaining of the clock difference between the terminal and the network device and the obtaining of the TA value may not be repeated here.

Fig. 15 shows a device diagram of a network device in an embodiment of the present application, including a receiver 1502, a processor 1503, and a transmitter 1505.

A receiver 1502 is configured to receive a first message carrying first time information of a terminal.

The first time information of the terminal is the time information when the terminal sends the first message. In the contention-based random access procedure, the receiver 1502 is configured to receive a random access preamble message or Msg3 message carrying first time information of the terminal; in the non-contention based random access procedure, the receiver 1502 is configured to receive a random access preamble message carrying first time information of the terminal.

The processor 1503 is configured to calculate a difference between the first time information of the terminal and the first time information of the network device in a scenario where the difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side, where the first time information of the network device is time information when the network device receives the first message, and optionally, the network device may include a timer 1501, and the timer 1501 records the first time information of the network device.

Optionally, the network device may include a memory 1504, where the memory 1504 is configured to store the difference between the first time information of the terminal and the first time information of the network device in a scenario where the difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side.

A transmitter 1505 for transmitting a message of the network device containing time information to the terminal.

The transmitter 1505 may be configured to send down a third message carrying third time information of the network device, where the third time information of the network device is time information when the network device sends the third message, and optionally, the network device may include a timer 1501, and the timer 1501 records the third time information of the network device.

In a scenario where a difference between the first time information of the terminal and the first time information of the network device is obtained at a network device side, the transmitter 1505 is configured to issue a second message carrying the difference between the first time information of the terminal and the first time information of the network device and second time information of the network device, where the second time information of the network device is time information when the network device sends the second message, and optionally, the network device may include a timer 1501, and the timer 1501 records the second time information of the network device.

In a scenario where a difference between the first time information of the terminal and the first time information of the network device is obtained at a terminal side, the transmitter 1505 is configured to issue a second message carrying the first time information of the terminal, the first time information of the network device, and the second time information of the network device.

In the contention-based random access procedure, the transmitter 1505 is configured to transmit a RAR message or a contention resolution message to the terminal; in the non-contention based random access procedure, the transmitter 1505 is used to send a RAR message to the terminal.

The timer, receiver, processor, memory, transmitter in the present terminal may be implemented on an IC, an analog IC, a radio frequency IC, a mixed signal IC, an ASIC, a printed circuit board, an electronic device, or the like. The timer, receiver, processor, memory, and transmitter in the present terminal may also be fabricated using various IC process technologies, such as Complementary Metal Oxide Semiconductor (CMOS), N-type metal oxide semiconductor (NMOS), P-type metal oxide semiconductor (PMOS), Bipolar Junction Transistor (BJT), bipolar CMOS, silicon germanium (SiGe), gallium arsenide (GaAs), and the like.

In an embodiment of the entity apparatus of the network device, the details of the recording of the first time information and the second time information of the network device and the calculation of the difference between the first time information of the terminal and the first time information of the network device may refer to steps of an embodiment of a method, and are not described herein again.

Fig. 16 shows a schematic block diagram of a terminal 1600 according to an embodiment of the application. As shown in fig. 16, the terminal can include a transceiver module 1602, a determination module 1606.

The transceiving module 1602 is configured to transceive an interactive message between the terminal and the network device, and the determining module 1606 is configured to determine a difference value, a transmission delay, and a TA value of clock information between the terminal and the network device, and optionally, the terminal includes a recording module 1604, and the recording module 1604 is configured to record time information of the terminal.

The transceiver module 1602 sends the first message to the network device, where the first message carries the first time information of the terminal, and optionally, the terminal includes a recording module 1604, and the recording module 1604 records the first time information of the terminal, where the first time information of the terminal is time information when the terminal sends the first message. The transceiver module 1602 receives a second message of the network device, where the second message carries a difference between first time information of the terminal and first time information of the network device, and second time information of the network device, where the first time information of the network device is time information when the network device receives the first message, and the second time information of the network device is time information when the network device sends the second message. Optionally, the terminal includes a recording module 1604, where the recording module 1604 records second time information of the terminal, and the second time information of the terminal is time information when the terminal receives the second message.

The determining module 1606 determines the difference between the clock information of the terminal and the clock information of the network device according to the difference between the first time information of the terminal and the first time information of the network device, the second time information of the terminal, and the second time information of the network device.

The transceiver module 1602 receives a third message of the network device, where the third message carries third time information of the network device, and optionally, the terminal includes a recording module 1604, and the recording module 1604 records the third time information of the terminal, where the third time information of the terminal is time information when the terminal receives the third message. And determining the transmission delay between the terminal and the network equipment according to the third time information which is triggered and issued by the network equipment and bears the network equipment and the third time information of the terminal when receiving the third message so as to determine a TA value, wherein the third time information of the network equipment is the time information when the network equipment sends the third message.

In the contention-based random access process, the transceiver module 1602 is configured to send a random access preamble message or Msg3 message, and receive a RAR message or a contention resolution message; in the non-contention based random access procedure, the transceiver module 1602 is configured to send a random access preamble message and receive a RAR message.

For example, the transceiver module 1602 is configured to support

steps

502, 512, 602, 614, 702, 714, 702, 712, 902, 912 in the flowchart of acquiring the timing advance.

The second time information of the terminal is time information when the terminal receives the second message, optionally, the terminal includes a recording module 1604, and the recording module 1604 may be configured to record the second time information of the terminal. For example, the recording module 1604 is configured to support

steps

510, 612, 712, 810, 812, 910 in the flowchart of acquiring the timing advance.

For example, the determining module 1606 is used to support

steps

510, 512, 602, 614, 702, 714, 802, 812, 902, 912 in the flowchart of acquiring the timing advance.

It should be understood that the terminal 1600 according to the embodiment of the present application may correspond to the terminal in the method for acquiring a timing advance between the terminal and the network device according to the embodiment of the present application, and each module and other operations and/or functions in the terminal 1600 are respectively for implementing corresponding flows of the methods in fig. 5 to fig. 9, and are not described herein again for brevity.

Therefore, in the embodiment of the present application, the terminal obtains time information through interaction with the network device, and the terminal determines the TA value according to the difference value of the time information. On one hand, the terminal can be used locally after obtaining the TA value, so that the transmission delay is small, the error of the TA measurement value is reduced, and the uplink signal of the terminal can be correctly decoded. On the other hand, after the clock information difference between the network device and the terminal is obtained, the terminal TA value can be continuously adjusted according to the third time information sent by the network device and the third time information of the terminal, so that signaling overhead is saved.

Fig. 17 is a schematic block diagram of a network device 1700 according to an embodiment of the present application, where the network device includes a transceiver module 1702 and a determination module 1706, as shown in fig. 17.

The transceiving module 1702 is configured to transceive an interactive message with a terminal, and optionally, the network device may further include a recording module 1704, where the recording module 1704 is configured to record time information of the network device.

The transceiver module 1702 receives a first message, where the first message carries first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message. Optionally, the network device may further include a recording module 1704, where the recording module 1704 records first time information of the network device, and the first time information of the network device is time information when the network device receives the first message. The transceiving module 1702 sends the second message, and optionally, the network device may further include a recording module 1704, where the recording module 1704 records second time information of the network device, where the second message carries the first time information of the terminal, the difference between the first time information of the network device, and the second time information of the network device is time information when the network device sends the second message. The determining module 1706 is configured to determine a difference between the first time information of the network device and the first time information of the terminal.

The transceiving module 1702 sends the third message, and optionally, the network device may further include a recording module 1704, where the recording module 1704 records third time information of the network device, where the third time information of the network device is carried in the third message, and the third time information of the network device is time information when the network device sends the third message.

For example, the transceiver module 1702 is configured to support the

steps

508, 610, 710 of the flowchart for acquiring the timing advance.

For example, the logging module 1704 is configured to support

steps

504, 506, 604, 608, 704, 708 of the flowchart of obtaining the timing advance.

For example, the determination module 1706 is used to support

steps

606, 706 in the flowchart of acquiring the timing advance.

It should be understood that the network device 1700 according to the embodiment of the present application may correspond to the network device in the method for acquiring the timing advance between the terminal and the network device according to the embodiment of the present application, and each module and other operations and/or functions in the network device 1700 are respectively for implementing corresponding flows of the methods in fig. 5 to fig. 7, and are not described herein again for brevity.

The network device 1700 shown in fig. 17 may further include a transceiver module 1702 and a recording module 1704. The transceiving module 1702 is configured to transceive an interactive message with a terminal, and the recording module 1704 is configured to record time information of the network device.

The transceiver module 1702 receives a first message, where the first message carries first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message. The recording module 1704 records first time information of the network device, where the first time information of the network device is time information when the network device receives a first message. The transceiving module 1702 sends a second message, and the recording module 1704 records second time information of the network device, where the second message carries the first time information of the terminal, the first time information of the network device, and the second time information of the network device is time information when the network device sends the second message.

The transceiving module 1702 sends a third message, and the recording module 1704 records third time information of the network device, where the third message carries the third time information of the network device, and the third time information of the network device is time information when the network device sends the third message.

For example, the transceiver module 1702 is configured to support step 808 in the flowchart of acquiring the timing advance as shown in fig. 8.

For example, the recording module 1704 is configured to support

steps

804, 806 in the flowchart of obtaining the timing advance as shown in fig. 8.

It should be understood that the network device 1700 according to the embodiment of the present application may correspond to the network device in the method for acquiring the timing advance between the terminal and the network device according to the embodiment of the present application, and each module and other operations and/or functions in the network device 1700 are respectively for implementing a corresponding flow of the method in fig. 8, and are not described herein again for brevity.

Therefore, in the embodiment of the present application, the network device obtains the time information through interaction with the terminal, and issues the time information to the terminal, so that the terminal can determine the TA value according to the time information. On one hand, the TA value can be locally used in the terminal, so the transmission delay is very small, the error of the TA measurement value is reduced, and the uplink signal of the terminal can be correctly decoded. On the other hand, after the clock information difference between the network device and the terminal is obtained, the network device issues time information to the terminal, and the terminal can adjust the TA value of the terminal according to the local time information, thereby saving signaling overhead.

the first time information of the terminal is time information when the terminal sends the first message, and optionally, the terminal may include a timer 1401, where the timer 1401 is configured to record the first time information of the terminal. In the contention-based random access procedure, the transmitter 1402 is configured to send a random access preamble message or Msg3 message carrying first time information of the terminal to the network device; in the non-contention based random access procedure, the transmitter 1402 is configured to transmit a random access preamble message carrying first time information of the terminal to the network device.

The receiver 1403 is configured to receive a second message, which is sent by the network device and carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device; or, the receiver 1403 may further receive a second message, which is sent by the network device and carries a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device. The first time information of the network device is time information when the network device receives a first message, the second time information of the network device is time information when the network device sends a second message, the first position information of the network device is position information when the network device receives the first message, and the second position information of the network device is position information when the network device sends the second message.

The processor 1405 acquires the position information of the terminal and the ephemeris information of the network device according to the first time information of the network device, the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first position information of the network device, and the second position information of the network device, or the processor 1405 acquires the position information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first position information of the network device, and the second position information of the network device, where the ephemeris information of the network device at least includes a moving track of the network device. Optionally, the terminal may include a timer 1401, the timer 1401 recording second time information of the terminal; the processor 1405 may further obtain the position information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first position information of the network device, and the second position information of the network device.

Optionally, the terminal may include a memory 1404, the memory 1404 configured to store ephemeris information of the network device and location information of the terminal required to determine the TA value.

A processor 1405, configured to further determine a TA value according to ephemeris information of the network device, location information of the terminal, third time information of the network device, and third time information of the terminal.

The processor 1405 determines the TA value according to the third time information of the network device, the third time information of the terminal, the ephemeris information of the network device, and the location information of the terminal, which are sent by the network device. The third time information of the terminal is the time information when the terminal receives the third message. Optionally, the terminal may include a timer 1401, and the timer 1401 records third time information of the terminal.

All or portions of timer 1401, transmitter 1402, and receiver 1403 may be implemented on one or more analog ICs, radio frequency ICs, mixed signal ICs, and the like.

Optionally, the terminal can include a memory 1404, the memory 1404 can store program codes and data for use by the processor 1405. Processor 1405 may be implemented on one or more ASICs and/or other ICs.

In an embodiment of the apparatus of the terminal, details of recording the first time information of the terminal and the second time information of the terminal, obtaining the position information of the terminal and the ephemeris information of the network device, and determining the TA value may refer to steps of the method embodiment, and are not described herein again.

Fig. 18 illustrates an apparatus diagram of a network device in an embodiment of the application, including a receiver 1802, a processor 1803, and a transmitter 1804.

A receiver 1802 for receiving a first message carrying first time information of a terminal.

In the contention-based random access procedure, the receiver 1802 is configured to receive a random access preamble message or Msg3 message carrying first time information of the terminal; in the non-contention based random access procedure, the receiver 1802 is configured to receive a random access preamble message carrying first time information of the terminal.

A processor 1803, configured to obtain first location information of the network device. Optionally, the network device may include a recorder 1801, where the recorder 1801 records first time information of the network device and first location information of the network device.

The transmitter 1804 transmits a second message to the terminal, where the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device; or the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device.

A processor 1803, configured to obtain second location information of the network device. Optionally, the network device may include a recorder 1801, where the recorder 1801 records second time information of the network device and second location information of the network device.

The transmitter 1804 may be configured to issue a third message carrying third time information of the network device, where the third time information of the network device is time information when the network device sends the third message, or the third message further includes third location information of the network device. Optionally, the network device may include a recorder 1801, where the recorder 1801 records third time information of the network device.

In a contention-based random access procedure, the transmitter 1804 is configured to send a RAR message or a contention resolution message to the terminal; the transmitter 1804 is configured to send a RAR message to the terminal in a non-contention based random access procedure.

The timer, receiver, processor transmitter in the present network device may be implemented on an IC, analog IC, radio frequency IC, mixed signal IC, ASIC, printed circuit board, electronic device, etc. The timer, receiver, processor, transmitter in the present network device may also be fabricated using various IC process technologies such as CMOS, NMOS, PMOS, BJT, bipolar CMOS, SiGe, GaAs, etc.

In an embodiment of the entity apparatus of the network device, the recording of the first time information of the network device and the second time information of the network device, and the obtaining of the first location information of the network device and the second location information of the network device and the detailed description of the recording may refer to the steps of the method embodiment and are not described herein again.

FIG. 19 shows a schematic block diagram of a terminal 1900 according to an embodiment of the application. As shown in fig. 19, the terminal may include a transceiver module 1902 and a determination module 1906.

The transceiver module 1902 is configured to receive and transmit an interactive message between the terminal and the network device, and the determining module 1906 is configured to obtain location information of the terminal, ephemeris information of the network device, transmission delay, and a TA value.

Optionally, the terminal includes a recording module 1904, and the recording module 1904 is configured to record time information of the terminal.

The transceiver module 1902 sends a first message to the network device, where the first message carries first time information of the terminal, optionally, the terminal includes a recording module 1904, and the recording module 1904 records the first time information of the terminal, where the first time information of the terminal is time information when the terminal sends the first message. The transceiver module 1902 receives a second message of the network device, where the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device; or the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device. Optionally, the terminal includes a recording module 1904, where the recording module 1904 records second time information of the terminal, and the second time information of the terminal is time information when the terminal receives the second message.

The determining module 1906 obtains the location information of the terminal and the ephemeris information of the network device according to the first time information of the network device, the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device; the determining module 1906 may further obtain the location information of the terminal and the ephemeris information of the network device according to a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device. Optionally, the terminal includes a storage module 1908, and the storage module 1908 is configured to store the location information of the terminal and the ephemeris information of the network device.

The transceiver module 1902 receives a third message of the network device, where the third message carries third time information of the network device, optionally, the terminal includes a recording module 1904, and the recording module 1904 records the third time information of the terminal, where the third time information of the terminal is time information when the terminal receives the third message. And the determining module determines the transmission delay between the terminal and the network equipment according to the third time information of the network equipment, the third time information of the terminal, the position information of the terminal and the ephemeris information of the network equipment so as to determine the TA value.

In the contention-based random access process, the transceiver module 1902 is configured to send a random access preamble message or Msg3 message, and receive a RAR message or a contention resolution message; in the non-contention based random access procedure, the transceiver module 1902 is configured to send a random access preamble message and receive a RAR message.

For example, the transceiver module 1902 is configured to support

steps

1002, 1012, 1102, 1112, 1202, 1212 in the flowchart of acquiring the timing advance.

The second time information of the terminal is time information when the terminal receives the second message, optionally, the terminal includes a recording module 1904, and the recording module 1904 may be configured to record the second time information of the terminal. For example, the recording module 1904 is used to support

steps

1010, 1110, 1210 in the flowchart of acquiring the timing advance.

For example, the determining module 1906 is used to support

steps

1010, 1012, 1110, 1112, 1210, 1212 in the flowchart of acquiring the timing advance.

It should be understood that the terminal 1900 according to the embodiment of the present application may correspond to the terminal in the method for acquiring a timing advance between the terminal and the network device according to the embodiment of the present application, and various modules and other operations and/or functions in the terminal 1900 are respectively for implementing corresponding flows of the methods in fig. 10 to fig. 12, and are not described herein again for brevity.

Therefore, in the embodiment of the present application, the terminal obtains the location information of the terminal and the ephemeris information of the network device through interaction with the network device, and the terminal determines the transmission delay between the terminal and the network device according to the third time information of the network device, the third time information of the terminal, the location information of the terminal, and the ephemeris information of the network device, so as to determine the TA value. On one hand, the terminal can be used locally after obtaining the TA value, so that the transmission delay is very small, the error of the TA measurement value is reduced, and the uplink signal of the terminal can be correctly decoded; on the other hand, in the above embodiment, in the process of determining the TA value, the position information of the terminal, the position information of the network device, and the ephemeris information of the network device are also taken into consideration, so that the error of the TA value is further reduced; after the clock information difference between the network device and the terminal is obtained, the terminal can continuously adjust the TA value of the terminal according to the third time information issued by the network device and the third time information of the terminal, thereby saving signaling overhead.

Fig. 20 shows a schematic block diagram of a network device 2000 according to an embodiment of the present application, which includes a transceiver module 2002 and a determination module 2006 as shown in fig. 20.

The transceiver module 2002 is configured to transceive an interaction message with a terminal, and the determining module 2006 is configured to determine location information of the network device, and optionally, the network device may further include a recording module 2004, and the recording module 2004 is configured to record time information of the network device.

The transceiver module 2002 receives a first message, where the first message carries first time information of the terminal, and the determining module 2006 obtains first location information of the network device. Optionally, the network device may further include a recording module 2004, where the recording module 2004 records first time information of the network device and first location information of the network device, the first time information of the network device is time information when the network device receives the first message, and the first location information of the network device is location information when the network device receives the first message.

The transceiver module 2002 sends a second message, where the second message carries the first time information of the network device, the second time information of the network device, the first time information of the terminal, the first location information of the network device, and the second location information of the network device; or the second message may further carry a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device. The determining module 2006 is configured to obtain second location information of the network device. Optionally, the network device may further include a recording module 2004, where the recording module 2004 records second time information of the network device and second location information of the network device, the second time information of the network device is time information when the network device sends the second message, and the second location information of the network device is location information when the network device sends the second message.

The transceiver module 2002 sends a third message, and optionally, the network device may further include a recording module 2004, where the recording module 2004 records third time information of the network device, where the third time information of the network device is carried in the third message, and the third time information of the network device is time information when the network device sends the third message.

For example, the transceiver module 2002 is configured to support

steps

1008, 1108, 1208 in the flowchart of acquiring the timing advance.

For example, the recording module 2004 is configured to support

steps

1004, 1006, 1104, 1106, 1204, 1206 of the flowchart of acquiring the timing advance.

For example, the determination module 2006 is configured to support

steps

It should be understood that the network device 2000 according to the embodiment of the present application may correspond to the network device in the method for acquiring the timing advance between the terminal and the network device according to the embodiment of the present application, and each module and other operations and/or functions in the network device 2000 are respectively for implementing corresponding flows of the methods in fig. 10 to fig. 12, and are not described herein again for brevity.

Therefore, in the embodiment of the present application, the network device obtains the time information through interaction with the terminal, and issues the time information to the terminal, so that the terminal can determine the TA value according to the time information. On one hand, the TA value can be locally used in the terminal, so the transmission delay is very small, the error of the TA measurement value is reduced, and the uplink signal of the terminal can be correctly decoded. And when the TA value is determined, the position information of the terminal, the position information of the network equipment and the ephemeris information of the network equipment are also taken into account, so that the error of the TA value is further reduced. On the other hand, after the clock information difference between the network device and the terminal is obtained, the network device issues time information to the terminal, and the terminal can adjust the TA value of the terminal according to the local time information, thereby saving signaling overhead.

Fig. 21 is a schematic structural diagram of a chip system 2100 according to an embodiment of the present disclosure. The chip system 2100 includes at least one processor 2102, a memory 2104, an interface circuit 2106 and a bus system 2108, the memory 2104 may include a read-only memory and a random access memory, and provides operating instructions and data to the processor 2102. A portion of memory 2104 may also include non-volatile random access memory.

In some embodiments, memory 2104 stores elements, executable modules or data structures, or a subset thereof, or an expanded set thereof.

In the embodiment of the present application, by calling the operation instruction stored in the memory 2104 (which may be stored in an operating system), a corresponding operation is performed.

One possible implementation is: the chip systems used for network devices or terminals are similar in structure, but different devices use different chip systems to implement their respective functions.

The processor 2102 controls the operation of the network device or the terminal, and the processor 2102 may also be referred to as a Central Processing Unit (CPU). Memory 2104 may include read-only memory and random access memory, and provides instructions and data to processor 2102. A portion of memory 2104 may also include non-volatile random access memory. The bus system 2108 includes a data bus, a power bus, a control bus, a status signal bus, and the like.

The methods disclosed in the embodiments of the present application described above may be implemented in the processor 2102 or implemented by the processor 2102. The processor 2102 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be performed by instructions in the form of hardware, integrated logic circuits, or software in the processor 2102. The processor 2102 may be a general purpose processor, a Digital Signal Processor (DSP), an ASIC, an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components. The various methods, steps, and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 2104, and the processor 2102 reads information in the memory 2104 and performs the steps of the above method in combination with hardware thereof.

Optionally, the interface circuit 2106 is used for performing the steps of receiving and transmitting of the network device or the terminal in the embodiments shown in fig. 5-12.

The processor 2102 is configured to perform the steps of the processing of the network device or the terminal in the embodiments shown in fig. 5-12.

Embodiments of the present application provide a computer-readable storage medium having instructions stored therein, which, when run on a terminal, cause the terminal to perform the steps performed by the terminal in the above embodiments (including all the steps performed by the terminal in fig. 5-12, such as 502, 510, 512, 602, 612, 614, 702, 712, 714, 802, 810, 812, 902, 910, 912, 1002, 1010, 1012, 1102, 1110, 1112, 1202, 1210, 1212).

Embodiments of the present application provide a computer-readable storage medium having stored therein instructions, which, when executed on a network device, cause the network device to perform the steps performed by the network device in the above embodiments (including all the steps performed by the network device in fig. 5-12, such as 504, 506, 508, 604, 606, 608, 610, 504, 506, 508, 510, 804, 806, 808, 904, 906, 908, 1004, 1006, 1008, 1104, 1106, 1108, 1204, 1206, 1208).

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules is merely a logical division, and in actual implementation, there may be other divisions, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of devices or modules through some interfaces, and may be in an electrical, mechanical or other form.

The modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical modules, may be located in one place, or may be distributed on a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

In addition, functional modules in the embodiments of the present application may be integrated into one module, or each module may exist alone, or two or more modules may be integrated into one module. The integrated module can be realized in a hardware form, and can also be realized in a form of hardware and a software functional module.

It is obvious to those skilled in the art that, for convenience and simplicity of description, the foregoing division of the functional modules is merely used as an example, and in practical applications, the above function distribution may be performed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to perform all or part of the above described functions. For the specific working process of the device described above, reference may be made to the corresponding process in the foregoing method embodiment, which is not described herein again.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

The above-mentioned embodiments, objects, technical solutions and advantages of the present application are further described in detail, it should be understood that the above-mentioned embodiments are only examples of the present application, and are not intended to limit the scope of the present application, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the present application should be included in the scope of the present application.

Claims

1. A method for obtaining a timing advance, TA, comprising:

the method comprises the steps that a terminal obtains position information of the terminal and ephemeris information of network equipment, wherein the ephemeris information of the network equipment at least comprises a moving track of the network equipment;

the terminal receives a message including time information of the network device;

and the terminal determines the time lead according to the time information of the network equipment, the time information when the terminal receives the message comprising the time information of the network equipment, the position information of the terminal and the ephemeris information of the network equipment.

2. The method of claim 1, wherein the obtaining, by the terminal, the position information of the terminal and the ephemeris information of the network device comprises:

the terminal sends a first message to the network equipment, wherein the first message comprises first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message;

the terminal receives a second message of the network equipment, wherein the second message comprises first time information of the network equipment, the first time information of the terminal, second time information of the network equipment, first position information of the network equipment and second position information of the network equipment; or the second message includes a difference between first time information of the network device and first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device, where the first time information of the network device is time information when the network device receives the first message, the second time information of the network device is time information when the network device sends the second message, the first location information of the network device is location information when the network device receives the first message, and the second location information of the network device is location information when the network device sends the second message;

the terminal acquires the position information of the terminal and the ephemeris information of the network equipment according to the first time information of the network equipment, the first time information of the terminal, the second time information of the network equipment, the second time information of the terminal, the first position information of the network equipment and the second position information of the network equipment, wherein the second time information of the terminal is the time information when the terminal receives the second message.

3. The method according to claim 2, wherein the first message is a random access preamble message in a random access procedure, and the second message is a Random Access Response (RAR) message in the random access procedure.

4. The method of claim 2, wherein the first message is a message Msg3 in a random access procedure, and wherein the second message is a contention resolution message in the random access procedure.

5. The method according to any of claims 1-4, wherein the terminal receives a message comprising time information of the network device; the determining, by the terminal, a timing advance according to the time information of the network device, the time information when the terminal receives the message including the time information of the network device, the location information of the terminal, and the ephemeris information of the network device, includes:

the terminal receives a third message sent by the network equipment and records third time information of the terminal, wherein the third time information of the terminal is time information when the terminal receives the third message, the third message comprises the third time information of the network equipment, and the third time information of the network equipment is time information when the network equipment sends the third message;

and the terminal determines the time advance according to the position information of the terminal, the ephemeris information of the network equipment, the third time information of the network equipment and the third time information of the terminal.

6. The method of claim 5, wherein the third time information of the network device is carried in a synchronization signal Block (SS Block).

7. The method of claim 6, wherein the third time information of the network device is obtained from a Physical Broadcast Channel (PBCH) in the synchronization signal block.

8. The method of claim 5, wherein the third time information of the network device is obtained from a Physical Broadcast Channel (PBCH) in a synchronization signal block.

9. The method of claim 6, wherein the third time information of the network device is obtained from a clock information frequency domain resource block in the synchronization signal block.

10. The method of claim 5, wherein the third time information of the network device is obtained from a clock information frequency domain resource block in a synchronization signal block.

11. A terminal, comprising:

the processor is used for acquiring the position information of the terminal and the ephemeris information of the network equipment, wherein the ephemeris information of the network equipment at least comprises a moving track of the network equipment;

a transmitter for transmitting a message including time information of the terminal;

a receiver for receiving a message including time information of the network device;

the processor is further configured to determine a timing advance TA according to the time information of the network device, the time information when the receiver receives the message including the time information of the network device, the location information of the terminal, and ephemeris information of the network device.

12. The terminal of claim 11,

the transmitter is specifically configured to send a first message to a network device, where the first message includes first time information of the terminal, and the first time information of the terminal is time information when the terminal sends the first message;

the receiver is specifically configured to receive a second message of the network device, where the second message includes first time information of the network device, first time information of the terminal, second time information of the network device, first location information of the network device, and second location information of the network device; or the second message includes a difference between the first time information of the network device and the first time information of the terminal, the second time information of the network device, the first location information of the network device, and the second location information of the network device, where the first time information of the network device is the time information when the network device receives the first message, the second time information of the network device is the time information when the network device sends the second message, the first location information of the network device is the location information when the network device receives the first message, and the second location information of the network device is the location information when the network device sends the second message;

the processor is specifically configured to obtain the location information of the terminal and ephemeris information of the network device according to the first time information of the network device, the first time information of the terminal, the second time information of the network device, the second time information of the terminal, the first location information of the network device, and the second location information of the network device, where the second time information of the terminal is time information when the terminal receives the second message.

13. The terminal of claim 12, wherein the first message is a random access preamble message in a random access procedure, and wherein the second message is a Random Access Response (RAR) message in the random access procedure.

14. The terminal of claim 12, wherein the first message is a message Msg3 in a random access procedure, and wherein the second message is a contention resolution message in the random access procedure.

15. The terminal according to any of claims 11-14,

the receiver is specifically configured to receive a third message sent by the network device, where the third message includes third time information of the network device, and the third time information of the network device is time information when the network device sends the third message;

the processor is specifically configured to determine the time advance according to the position information of the terminal, the ephemeris information of the network device, third time information of the network device, and third time information of the terminal, where the third time information of the terminal is time information when the receiver receives the third message.

16. The terminal of claim 15, wherein the third time information of the network device is carried in a synchronization signal Block SS Block.

17. The terminal of claim 16, wherein the third time information of the network device is obtained from a Physical Broadcast Channel (PBCH) in the synchronization signal block.

18. The terminal of claim 15, wherein the third time information of the network device is obtained from a Physical Broadcast Channel (PBCH) in a synchronization signal block.

19. The terminal of claim 16, wherein the third time information of the network device is obtained from a clock information frequency domain resource block in the synchronization signal block.

20. The terminal of claim 15, wherein the third time information of the network device is obtained from a clock information frequency domain resource block in a synchronization signal block.