Timing advance reporting method and communication device

Abstract

The embodiment of the invention provides a timing advance reporting method and a communication device. Timing advance reporting in a cell switching process can be realized. The method comprises the following steps: receiving a switching command from access network equipment; wherein the switching command is used for indicating the terminal equipment to be switched from the source cell to the target cell. And when the switching command carries the first indication information and / or the second indication information, triggering the reporting of the timing advance. Wherein the timing advance is the timing advance corresponding to the target cell, the first indication information is used for indicating an offset threshold of the timing advance reported by the terminal equipment, and the second indication information is used for indicating the terminal equipment to report the timing advance.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of communications, and in particular to a timing advance reporting method and a communication device. Background Art

[0002] Timing advance (TA) is used for uplink transmission of terminal equipment, which means that the system frame of uplink data sent by the terminal equipment is a certain time ahead of the received downlink frame. In the non-terrestrial network (NTN) communication system, TA includes the transmission delay from the terminal equipment to the satellite and the transmission delay from the satellite to the reference point (RP). Among them, the transmission delay from the terminal equipment to the satellite is the round-trip time (RTT) of the service link, which can be expressed as RTT. It is calculated by the terminal equipment based on the global navigation satellite system (GNSS) information and ephemeris information. The transmission delay from the satellite to the RP is represented by Common TA, which is calculated by the network side and sent to the terminal equipment.

[0003] In NTN, the current 3rd generation partnership project (3GPP) protocol stipulates the following three trigger conditions for terminal devices to report TA: (1) When the terminal device receives a TA report indication from the network, TA reporting is triggered; (2) When the terminal device receives the configuration of a TA offset threshold (offsetThresholdTA) and the terminal device has not reported TA in the current serving cell, TA reporting is triggered; (3) When the network configures TA for the terminal device and the change in the current TA estimate of the terminal device compared with the last reported TA value exceeds the threshold offsetThresholdTA, TA reporting is triggered.

[0004] Among the above three conditions for triggering TA reporting, condition (1) is the TA reporting process of the terminal device in the random access phase, and conditions (2) and (3) are the TA reporting process of the terminal device in the non-switching scenario in the connected state. However, the above three conditions for triggering TA reporting do not specify the TA reporting triggering conditions of the terminal device during the cell switching process. Therefore, how to implement TA reporting during the cell switching process has become an urgent problem to be solved. Summary of the invention

[0005] The embodiments of the present application provide a timing advance reporting method and a communication device, which can implement TA reporting during cell switching.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] In a first aspect, a timing advance reporting method is provided, which can be executed by a terminal device, or by a component of the terminal device, such as a processor, a chip, or a chip system of the terminal device, or can be implemented by a logic module or software that can implement all or part of the functions of the terminal device. The method includes: receiving a switching command from an access network device. The switching command is used to instruct the terminal device to switch from a source cell to a target cell. In the case where the switching command carries the first indication information and / or the second indication information, the timing advance reporting is triggered. The timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to instruct the terminal device to report the timing advance.

[0008] Based on the timing advance reporting method, it is clarified whether the terminal device reports the timing advance corresponding to the target cell when the switching command carries the timing advance offset threshold (such as the first indication information) and / or the timing advance reporting indication (such as the second indication information), which can ensure that the accurate timing advance reporting is triggered during the cell switching. It should be understood that the access network device that sends the switching command in the embodiment of the present application is the access network device corresponding to the source cell.

[0009] In a possible design scheme, when the handover command carries the first indication information and / or the second indication information, triggering the timing advance reporting may include: if the handover command carries the first indication information, triggering the timing advance reporting during the random access to the target cell or after the random access to the target cell is successful. Based on this design scheme, when the handover command carries the first indication information, the terminal device may trigger the timing advance reporting during the random access to the target cell or after the random access is completed.

[0010] In a possible design scheme, in the case where the handover command carries the first indication information and / or the second indication information, triggering the timing advance reporting may include: if the handover command carries the first indication information and the second indication information, triggering the timing advance reporting during the random access to the target cell or after the random access to the target cell is successful. Based on the design scheme, in the case where the handover command carries the first indication information and the second indication information, the terminal device may trigger the timing advance reporting during the random access to the target cell or after the random access is completed.

[0011] In a possible design scheme, triggering timing advance reporting when the switching command carries the first indication information and / or the second indication information may include: when the terminal device is configured for cell switching based on RACH-less, if the switching command carries the first indication information and / or the second indication information, triggering timing advance reporting after the cell switching is completed. Based on this design scheme, when the terminal device switches the cell based on RACH-less, the terminal device may trigger timing advance reporting after the cell switching is completed.

[0012] In a possible design scheme, the switching command may be a radio resource control RRC reconfiguration message carrying synchronization reconfiguration.

[0013] In a second aspect, a timing advance reporting method is provided, which can be executed by an access network device, or by a component of the access network device, such as a processor, chip, or chip system of the access network device, or can be implemented by a logic module or software that can implement all or part of the functions of the access network device. The method includes: sending a switching command to a terminal device. The switching command is used to instruct the terminal device to switch from a source cell to a target cell, and the switching command carries a first indication information and / or a second indication information. Receive the timing advance from the terminal device. The timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to instruct the terminal device to report the timing advance.

[0014] Among them, the technical effects of the second aspect can refer to the description of the technical effects in the first aspect, and will not be elaborated on here.

[0015] In a third aspect, a timing advance reporting method is provided, which can be executed by a terminal device, or by a component of the terminal device, such as a processor, a chip, or a chip system of the terminal device, or can be implemented by a logic module or software that can implement all or part of the terminal device functions. The method includes: receiving a radio resource control RRC reconfiguration message from an access network device, wherein the RRC reconfiguration message is used to instruct the terminal device to switch from a source cell to a target cell. In the case where the RRC reconfiguration message carries the first indication information but does not carry the second indication information, it is determined that the timing advance reporting is not triggered. The timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to instruct the terminal device to report the timing advance.

[0016] In one possible design, the RRC reconfiguration message may carry synchronous reconfiguration.

[0017] In a fourth aspect, a communication method is provided, which can be executed by a terminal device, or by a component of the terminal device, such as a processor, a chip, or a chip system of the terminal device, or can be implemented by a logic module or software that can implement all or part of the functions of the terminal device. The method includes: receiving a switching command from an access network device. The switching command is used to instruct the terminal device to switch from a source cell to a target cell. In the case where the switching command does not carry the second indication information and the terminal device reuses the configuration of the source cell, it is determined that the access network device has configured an offset threshold of the timing advance of the target cell. The second indication information is used to instruct the terminal device to report the timing advance.

[0018] In a possible design scheme, the switching command may be a radio resource control RRC reconfiguration message carrying synchronization reconfiguration.

[0019] In a fifth aspect, a communication device is provided. The communication device includes: a module, unit, or means for executing the method described in any one of the first aspect to the fourth aspect, and the module, unit, or means can be implemented by hardware, software, or by hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units corresponding to the above functions, such as a transceiver module and a processing module. For example, the transceiver module is used to indicate the transceiver function of the communication device, and the processing module is used to execute functions of the communication device other than the transceiver function.

[0020] In a possible design, the transceiver module may include a receiving module and a sending module, wherein the sending module is used to implement the sending function of the communication device described in the fifth aspect, and the receiving module is used to implement the receiving function of the communication device described in the fifth aspect.

[0021] In a possible design scheme, the communication device described in the fifth aspect may further include a storage module, which stores a program or instruction. When the processing module executes the program or instruction, the communication device described in the fifth aspect can execute the method described in any one of the first to fourth aspects.

[0022] Among them, the communication device described in the fifth aspect can be a terminal device or an access network device, or it can be a chip (system) or other parts or components that can be set in the terminal device or access network device, or it can be a device that includes a terminal device or an access network device, and this application does not limit this.

[0023] In a sixth aspect, a communication device is provided, comprising: a processor and a communication interface; the communication interface is used to communicate with a module outside the communication device; the processor is used to execute a computer program or instruction so that the communication device executes the method described in any one of the first to fourth aspects above.

[0024] In a seventh aspect, a communication device (for example, the communication device may be a chip or a chip system) is provided, wherein the communication device includes a processor for implementing the functions involved in any one of the first to fourth aspects above.

[0025] In some possible designs, the communication device includes a memory for storing necessary program instructions and / or data.

[0026] In one possible design, the processor may be integrated with the memory.

[0027] In some possible designs, when the communication device is a chip system, it can be composed of a chip, or it can include a chip and other discrete devices.

[0028] In an eighth aspect, a communication device is provided, comprising: a transceiver and a processor, wherein the transceiver is used for information exchange between the communication device and other communication devices, and the processor executes program instructions to execute the method described in any one of the first to fourth aspects.

[0029] In a possible design scheme, the communication device described in the eleventh aspect may further include a memory. The memory may be integrated with the processor or may be separately provided. The memory may be used to store the computer program and / or data involved in the method described in any one of the first to fourth aspects above.

[0030] It should be understood that the sixth to eighth aspects include the corresponding modules, units, or means for implementing the method described in any one of the first to fourth aspects, and the modules, units, or means can be implemented by hardware, software, or by hardware executing the corresponding software. The hardware or software includes one or more modules or units for executing the functions involved in the above method.

[0031] It can be understood that when the communication device provided in any one of the sixth to eighth aspects is a chip, the above-mentioned sending action / function can be understood as output, and the above-mentioned receiving action / function can be understood as input.

[0032] In a ninth aspect, a computer-readable storage medium is provided, in which a computer program or instruction is stored. When the computer-readable storage medium is run on a communication device, the communication device can execute the method described in any one of the first to fourth aspects above.

[0033] In a tenth aspect, a computer program product comprising instructions is provided, which, when executed on a communication device, enables the communication device to execute the method described in any one of the first to fourth aspects.

[0034] In the eleventh aspect, a communication system is provided, comprising a terminal device for executing the method described in the first aspect and an access network device for executing the method described in the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of an architecture of two satellite communications provided in an embodiment of the present application;

[0036] Figure 2 A schematic diagram of a scenario of TA calculation in NTN communication provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a cell switching process provided in an embodiment of the present application;

[0038] Figure 4 A schematic diagram of a 4-step random access process provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of a two-step random access process provided in an embodiment of the present application;

[0040] Figure 6 A schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0041] Figure 7 A schematic diagram of the structure of an access network device based on a CU-DU separation architecture provided in an embodiment of the present application;

[0042] Figure 8 A flowchart of a timing advance reporting method provided in an embodiment of the present application;

[0043] Fig. 9 A flowchart of another timing advance reporting method provided in an embodiment of the present application;

[0044] Fig.10 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0045] Fig.11 A schematic diagram of the structure of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following is a description of the related technologies involved in the embodiments of the present application.

[0047] 1. NTN communication

[0048] Non-terrestrial communications have the advantages of wide coverage, long communication distance, high reliability, high flexibility, and high throughput. They are not affected by geographical environment, climatic conditions, and natural disasters, and have been widely used in aviation communications, maritime communications, military communications, and other fields. Introducing NTN into the fifth generation (5G) mobile network can improve the performance of the communication system. Satellite communication systems and high altitude platform station (HAPS) communication systems are typical non-terrestrial communication systems. On the one hand, satellite networks can provide communication services for areas that are difficult to cover with terrestrial networks, such as oceans, forests, deserts, or remote areas; on the other hand, satellite networks can enhance the reliability of 5G communications, such as providing more stable communication services for users in high-speed mobile scenarios such as trains and airplanes. In addition, satellite networks can also provide more data transmission resources and support a larger number of connections.

[0049] Generally speaking, the higher the satellite's orbit, the larger its coverage area, but the longer the communication delay. According to the orbital altitude, satellites can be divided into:

[0050] (1) Low Earth Orbit (LEO): orbit altitude is 160 to 2000 kilometers (km);

[0051] (2) Medium Earth Orbit (MEO): orbital altitude is 2000~35786km;

[0052] (3) Geostationary Earth Orbit (GEO): orbital altitude is 35786 km;

[0053] Among them, GEO is a synchronous earth satellite orbit, and the satellites operating in this orbit are stationary relative to the ground; LEO and MEO are collectively referred to as non-geostationary orbits (NGSO), and the satellites operating in such orbits move at high speed relative to the ground.

[0054] For NGSO, depending on whether the satellite beam moves with the satellite, it can be further divided into Earth Moving Cell and Earth Fixed Cell. For Earth Moving Cell, the cell moves relative to the ground, and the satellite beam points to follow the satellite movement; for Earth Fixed Cell, the cell is fixed relative to the ground for a certain period of time, and the satellite antenna can use its beamforming capability to point the beam to a certain area fixed on the ground for a certain period of time.

[0055] According to the working mode, satellites can be generally divided into two categories. The first type is transparent forwarding, such as Figure 1 As shown in (a) in the figure, the satellite forwards the cell information of the ground network equipment (such as the next generation Node-B (gNB)). The function of the satellite is to filter, convert and amplify the wireless frequency. That is, the satellite mainly acts as a layer 1 relay (L1 relay) to regenerate the physical layer signal and does not have other higher protocol layers. The second type is regenerative, and the satellite has the processing function of the base station. In the regenerative working mode, it can be divided into regenerative satellites without inter-satellite links, that is, there is no inter-satellite link (ISL) between satellites, such as Figure 1 As shown in (b); a regenerative satellite with an inter-satellite link, that is, there is an interface between satellites for direct data exchange, where the inter-satellite link is an Xn interface; there is also an architecture in which the satellite only has the distributed unit (DU) processing function of the base station, and the satellite acts as a DU in this scenario.

[0056] 2. TA

[0057] An important feature of uplink transmission is that uplink transmissions from different terminal devices in the same cell do not interfere with each other. In order to ensure the orthogonality of uplink transmission and avoid intra-cell interference, the base station requires that the time at which signals from different terminal devices in the same subframe but different frequency domain resources (different resource blocks (RB)) arrive at the base station is basically aligned. As long as the base station receives the uplink data sent by the terminal device within the cyclic prefix (CP) range, it can correctly decode the uplink data. Therefore, uplink synchronization requires that the time at which signals from different terminal devices in the same subframe arrive at the base station falls within the cyclic prefix range.

[0058] In order to ensure time synchronization on the receiving side (base station side), long term evolution (LTE) / new radio (NR) introduces an uplink timing advance mechanism. From the perspective of the terminal device side, TA is essentially a negative offset between the start time of receiving the downlink subframe and the time of transmitting the uplink subframe. The base station can control the time when uplink signals from different terminal devices arrive at the base station by properly controlling the offset of each terminal device. For terminal devices that are far away from the base station, due to the large transmission delay, they need to send uplink data earlier than terminal devices that are closer to the base station.

[0059] In a terrestrial network (TN), a base station sends a timing advance command to a terminal device in two ways:

[0060] (1) During the random access process, the base station determines the TA value by measuring the received preamble and sends it to the terminal device through the Timing Advance Command field in the random access response (RAR). This process is called the "initial uplink synchronization process".

[0061] (2) In the radio resource control (RRC) connected state (RRC_CONNECTED), the base station needs to maintain TA information. Although the terminal device and the base station have achieved uplink synchronization during the random access process, the timing of the uplink signal reaching the base station may change over time. Therefore, the terminal device needs to continuously update its uplink timing advance to maintain uplink synchronization. In LTE / NR, the base station determines the TA value of each terminal device based on measuring the uplink transmission of the corresponding terminal device. In theory, any signal sent by the terminal device, such as sounding reference signal (SRS) / demodulation reference signal (DMRS) / channel quality indicator (CQI) / acknowledgement (ACK) / negative acknowledgement (NACK) / downlink physical shared channel (PUSCH), etc., can be used to measure TA. If a specific terminal device needs correction, the base station will send a Timing Advance Command to the terminal device, requesting it to adjust the uplink transmission timing. The Timing Advance Command is sent to the terminal device via a timing advance command media access control (MAC) control element (CE) (Timing Advance Command MAC-CE).

[0062] In NTN, Figure 2As shown in FIG. 1 , TA includes the transmission delay from the terminal device to the satellite and the transmission delay from the satellite to the RP. Specifically, TA can be determined according to the following formula:

[0063] TA=N_TA+N_TA,offset+N_TA,adj^Common+N_TA,adj^UE;

[0064] Among them, N_TA is the TA adjustment amount, which is the TA adjustment amount calculated by the network side according to the time of the actual received uplink data and the TA value reported by the terminal device; N_TA,offset is the fixed uplink and downlink frame offset configured by the network side, which is a finite fixed value in the time division duplexing (TDD) system and 0 in the frequency division duplexing (FDD) system; N_TA,adj^Common is the transmission delay from the satellite to the RP, expressed by the common Common TA, which is calculated by the network side and sent to the terminal device; N_TA,adj^UE is the transmission delay from the terminal device to the satellite, which is the service link transmission delay, calculated by the terminal device based on the GNSS information and ephemeris information.

[0065] The terminal device can report TA through MAC-CE. Before reporting TA, it is necessary to generate MAC-CE for TA reporting. MAC-CE always uses the latest TA report package, that is, when multiple TA reports are triggered, the latest TA is always used for package assembly. The generation process of MAC-CE for TA reporting is as follows:

[0066] - If at least one TA report is triggered and the triggered TA report has not been cancelled;

[0067] - If the uplink shared channel (UL-SCH) is available and the UL-SCH resources are sufficient to carry the TA report;

[0068] - A TA reporting MAC CE (Timing Advance Report MAC CE) is generated; - Otherwise, a scheduling request may be triggered to request UL-SCH resources.

[0069] The condition for the availability of UL-SCH resources is: if the MAC entity has configured, received or confirmed the uplink grant (UL Grant), the UL-SCH resources are considered available. In addition, if the MAC packet data unit (PDU) carrying the TA reporting MAC-CE has been sent, the previously triggered TA report will be cancelled.

[0070] 3. Cell switching

[0071] Due to the movement of the terminal device, the signal quality of the network currently accessed by the terminal device may deteriorate, and it is necessary to switch to a cell with better signal quality to obtain services. In the traditional switching process, the switching of the terminal device is controlled by the access network device, that is, the access network device sends a switching command to instruct the terminal device which cell to switch to and how to switch. Figure 3 As shown, after receiving the handover command, the terminal device accesses the target cell according to the content contained in the handover command. Therefore, the network side needs to obtain the target cell identifier. The handover steps are as follows:

[0072] S301, the source base station sends an RRC reconfiguration message to the terminal device. Correspondingly, the terminal device receives the RRC reconfiguration message from the source base station.

[0073] The source base station sends an RRC reconfiguration message to a terminal device in a connected state to instruct the terminal device to perform measurement, wherein the RRC reconfiguration message includes parameters such as a measurement object, a report configuration, and a measurement identifier.

[0074] S302: The terminal device sends a measurement report (Measure Report) to the source base station. Correspondingly, the source base station receives the measurement report from the terminal device.

[0075] After the terminal device measures the cell according to the RRC reconfiguration message, it generates a measurement report to report various events to the source base station.

[0076] S303: The source base station executes a handover decision.

[0077] After receiving the measurement report, the source base station determines, based on the measurement report, to perform a cell handover, that is, to switch from the source base station to the target base station.

[0078] S304: The source base station sends a handover request (Handover Request) to the target base station. Correspondingly, the target base station receives the handover request from the source base station.

[0079] S305: The target base station performs admission control.

[0080] The target base station determines whether to allow the terminal device to access based on the switching request. If the judgment result is allowed, it sends a switching confirmation message to the source base station, where the switching request confirmation includes parameters such as the new cell-radio network temporary identifier (C-RNTI) and the target base station security-related algorithm.

[0081] S306: The target base station sends a handover request acknowledgment (Handover Request ACK) to the source base station. Correspondingly, the source base station receives the handover request acknowledgment from the target base station.

[0082] S307: The source base station sends an RRC reconfiguration message to the terminal device. Correspondingly, the terminal device receives the RRC reconfiguration message from the source base station.

[0083] After receiving the switching confirmation message from the target base station, the source base station sends an RRC reconfiguration message (switching command) to the terminal device. The content contained in the RRC reconfiguration message comes from the switching request confirmation of S306. Specifically, the switching command in the NR system contains relevant information of the target cell and the relevant configuration parameters required for the terminal device to access the target cell. For example, target cell information (such as the physical cell identifier (PCI) of the target cell and the frequency information corresponding to the target cell), the C-RNTI allocated by the target cell to the terminal device, the random access channel (RACH) resource information required to access the target cell (such as dedicated RACH resources and / or public RACH resources), etc.

[0084] S308: The terminal device performs random access to the target base station.

[0085] The terminal device initiates random access to the target base station according to the handover command. In the existing handover process, the terminal device will disconnect from the source base station, and there will be a short interruption in the data transmission and reception of the terminal device before successfully accessing the target base station.

[0086] S309: The terminal device sends an RRC Reconfiguration Complete message to the target base station. Correspondingly, the target base station receives the RRC Reconfiguration Complete message from the terminal device.

[0087] The above is an overview of the existing cell switching process. For specific implementation, please refer to the description in the relevant prior art, which will not be described in detail.

[0088] Cell switching can be intra-site switching or inter-site switching. Intra-site switching may refer to the source cell and the target cell belonging to the same access network device (such as a base station), wherein the source cell and the target cell may be the same cell or different cells; inter-site switching refers to the source cell and the target cell belonging to different access network devices (such as a base station). This application does not limit this. It should be understood that the cell is the coverage area of ​​the access network device, the source cell corresponds to the source access network device (such as the source base station), and the target cell corresponds to the target access network device (such as the target base station). In the embodiment of the present application, cell switching mainly refers to inter-site switching.

[0089] It should also be understood that the source cell and the target cell may belong to the same access network device, or in other words, the source cell and the target cell may be co-located. In this case, for a certain terminal device, the TA corresponding to the target cell may be equal to the TA corresponding to the source cell. The target cell may also be a small cell, in which case, for a certain terminal device, the TA of the target cell may be 0.

[0090] 4. Random access (RA)

[0091] Random access is the process from when the terminal device starts to send a random access preamble to the access network device it is trying to access, to when a connection is established between the terminal device and the access network device. The random access process may occur during handover, RRC re-establishment, and other processes.

[0092] Random access includes contention based random access (or contention based random access or competitive random access, etc.) (contention based random access, CBRA) and non-contention based random access (or non-contention based random access or non-contention random access) (contention free random access, CFRA). Among them, CBRA can be applied to scenarios such as cell switching, or downlink data transmission needs but loss of synchronization, and CFRA can refer to random access initiated by a terminal device at a random access occasion (RO) specified by the access network device using a preamble specified for non-contention random access.

[0093] The following takes a terrestrial network (TN) as an example to introduce 4-step random access and 2-step random access of contention-based random access.

[0094] For example, Figure 4 FIG. 4 is a flow chart of a 4-step random access process. Figure 4 As shown, the 4-step random access may include the following steps:

[0095] S401: The terminal device sends an RA preamble to the access network device. Correspondingly, the access network device receives the RA preamble from the terminal device.

[0096] Among them, the RA preamble code can be used to estimate the uplink time difference between the terminal device and the access network device.

[0097] The RA preamble code may also be referred to as the first message or message (Msg) 1, or message one in the RA process.

[0098] S402: In response to the RA preamble, the access network device sends a random access response (RAR) to the terminal device. Correspondingly, the terminal device receives the RAR from the access network device.

[0099] The RAR includes TA, uplink (UL) grant and cell-radio network temporary identifier (C-RNTI), etc. The RAR can also be used to indicate that the access network device has successfully received the RA preamble from the terminal device.

[0100] RAR is also called message 2 in the RA process, and can also be called Msg2, or the second message. Among them, RAR can be carried on a physical downlink shared channel (PDSCH). It can be understood that the same PDSCH can carry RARs corresponding to multiple terminal devices.

[0101] S403: The terminal device sends message 3 to the access network device. Correspondingly, the access network device receives message 3 from the terminal device.

[0102] Message three is also called Msg3 or the third message in the RA process. Here, the content of Msg3 may be different depending on the terminal device status and application scenarios. For the RRC_IDLE / INACTIVE state, when the terminal device initiates random access, Msg3 carries the common control channel (CCCH) service data unit (SDU) content. For the RRC_CONNECTED state, when the terminal device initiates random access, Msg3 carries C-RNTI.

[0103] S404: The access network device sends message 4 to the terminal device. Correspondingly, the terminal device receives message 4 from the access network device.

[0104] Among them, message four can also be called a contention resolution message in the RA process, Msg4, or the fourth message.

[0105] If Msg3 carries CCCH SDU, then Msg4 carries the content or part of the content of Msg3. If the content of Msg4 received by the terminal device matches that of Msg3, it is considered that the contention is resolved and the random access process is successful. If Msg3 carries C-RNTI, then Msg4 carries the physical downlink control channel (PDCCH) addressed to the C-RNTI (the PDCCH transmission is addressed to the C-RNTI). If Msg4 carries the PDCCH addressed to the C-RNTI of the terminal device, it is considered that the contention is resolved and the random access process is successful.

[0106] It should be understood that, based on the different random access triggering scenarios, except that Msg1 is used to transmit the preamble unchanged, the messages corresponding to Msg2 / 3 / 4 may be different from Msg2 / 3 / 4 in the random access process used for cell access. For example, in the reconstruction process, Msg2 is RAR, and Msg3 is the "RRCReestablishmentRequest" message, and Msg4 includes the content or part of the content of the "RRCReestablishmentRequest" message; in the random access process initiated by the terminal device in the RRC_IDLE state, Msg2 is RAR, and Msg3 is the "RRCSetupRequest" message, and Msg4 includes the content or part of the content of the "RRCSetupRequest" message. In the random access process initiated by the terminal device in the RRC_INACTIVE state, Msg2 is RAR, and Msg3 is the RRC resume request message, and Msg4 includes the content or part of the content of the RRC resumerequest message. In the random access process initiated by the terminal device in the RRC_CONNECTED state, Msg2 is the RAR, Msg3 is the MAC-CE carrying the C-RNTI, and Msg4 is the PDCCH addressed to the C-RNTI of the UE.

[0107] Figure 4 The process of random access based on contention is shown. For random access based on non-contention, the step of contention resolution is omitted, that is, there is no process described in S404, which will not be described in detail.

[0108] In NTN, the terminal device can obtain the satellite ephemeris information and the transmission delay from the satellite to the reference point (for example, Common TA) through the system message, so that the terminal device can obtain the estimated value of TA. In addition, the terminal device has compensated for TA when sending the preamble. The terminal device can report the TA value to the network through MAC-CE. The terminal device can report TA in Msg3, Msg5, or other uplink transmission processes.

[0109] For example, Figure 5 FIG. 2 is a flow chart of a two-step random access process. Figure 5 As shown, the 2-step random access includes the following steps:

[0110] S501: The terminal device sends MsgA to the access network device. Correspondingly, the access network device receives MsgA from the terminal device.

[0111] Among them, MsgA sends the above-mentioned Msg1 and Msg3 together, including preamble and data.

[0112] S502: The access network device sends MsgB to the terminal device. Correspondingly, the terminal device receives MsgB from the access network device.

[0113] Among them, MsgB is sent together with the above-mentioned Msg2 and Msg4, including relevant information for resolving contention between terminal devices.

[0114] 5. RACH-less HO

[0115] In order to reduce the delay caused by the random access process, the terminal device can initiate a switch from the source cell to the target cell based on the RACH-less switch, that is, the terminal device can skip (not perform) the random access process with the target cell. The terminal device can determine the TA value through the ephemeris information and GNSS location information and the commonTA broadcast by the network device. After receiving the switching command, the terminal device can use the UL grant indicated in the message to send a TA value or an RRC reconfiguration completion message to the target access network device according to the switching command, such as the RRC reconfiguration message described above, without performing the random access process. Optionally, the switching message may include indication information, which is used to instruct the terminal device to perform RACH-less switching.

[0116] 6. NTN's TA reporting mechanism

[0117] The 3GPP protocol specifies the following three trigger conditions for terminal devices to report TA:

[0118] (1) When the terminal device receives a TA report indication from the network, it triggers TA reporting;

[0119] (2) When the terminal device receives the configuration of the TA offset threshold (offsetThresholdTA) and the terminal device has not reported the TA in the current serving cell, the TA reporting is triggered;

[0120] (3) When the change between the current TA of the terminal device and the last reported TA value (the latest reported TA) exceeds the threshold offsetThresholdTA, TA reporting is triggered.

[0121] In the above condition (1), the TA-report indication can be carried in the system information block (SIB) 19 message. If SIB19 carries the indication information, the terminal device reports the TA during the random access process during RRC connection establishment, RRC connection reconstruction, and RRC connection recovery. The TA-report indication can also be carried in dedicated signaling, for example, it can be carried in a handover command. If the UE handover command carries the ta-report indication, the UE reports the TA during the random access process during the handover process. Therefore, this condition determines whether it is necessary to trigger the TA report during the random access process based on whether the ta-report indication is configured.

[0122] Among the above three conditions for triggering TA reporting, condition (1) is the TA reporting process of the terminal device in the random access phase, and conditions (2) and (3) are the TA reporting process of the terminal device in the non-switching scenario in the connected state. However, none of the above three conditions for triggering TA reporting clearly states the TA reporting triggering conditions when the terminal device does not configure TA-report during the cell switching process but configures offsetThresholdTA. Based on the understanding of the three triggering TA reporting described in the above protocol, if the access network device configures offsetThresholdTA in the switching command, whether the terminal device reports TA, or when to report, can be understood as follows:

[0123] If the current serving cell is understood as the source cell (because the terminal device has not yet completed the cell handover and is still accessing the source cell), since the terminal device has previously accessed the source cell, it is likely that the TA corresponding to the source cell has been reported. In this case, there is no need to report the TA. If the current cell is understood as the target cell (because the terminal device has the target cell configuration in effect at this time, the target cell can be considered the current serving cell), the terminal device needs to determine condition (2). If the terminal device has not reported the TA corresponding to the target cell, the terminal device may need to report the TA corresponding to the target cell. Based on different understandings, it is unclear whether the TA is reported, and it is also unclear whether the TA of the source cell or the target cell is reported. If the terminal device and the access network device are based on different understandings, the actual behavior of the terminal device may be inconsistent with the terminal device behavior expected by the access network device.

[0124] In addition, according to the current understanding of the protocol, the judgment shown in condition (2) is executed when the terminal device receives offsetThresholdTA for the first time. That is to say, when the terminal device receives the TA reporting offset threshold for the first time, it is considered to have configured the value, and receiving offsetThresholdTA again is considered to be reconfiguration, i.e., reconfiguration. For reconfiguration, the terminal device does not trigger the evaluation of condition (2), and therefore does not trigger TA reporting. If the terminal device receives the configuration of the source cell in the current serving cell, and then receives the configuration of the target cell, it is unclear whether the received configuration of the target cell is the first configuration or reconfiguration, and whether the TA reporting should be triggered.

[0125] In addition, according to the current protocol, if the RRC reconfiguration message does not carry the timing advance reporting configuration (TAR-Config), the terminal device reuses or inherits the previous configuration (the configuration includes offsetThresholdTA). How to understand whether the access network device has configured offsetThresholdTA during the cell switching process? In other words, whether the terminal device reuses the previous configuration is considered to have configured this parameter, and the current protocol description is not clear.

[0126] Therefore, it is unclear whether the cell switching process needs to trigger TA reporting and whether to report the TA of the source cell or the target cell. Therefore, the embodiment of the present application provides a timing advance reporting method to solve the TA problem during the cell switching process. The method provided by the embodiment of the present application can be applied to the transparent satellite architecture and the regenerative satellite architecture, and can also be applied to the Earth Moving Cell and Quasi-Earth Fixed Cell scenarios.

[0127] In order to better understand the embodiments of the present application, the following explanations are made before introducing the embodiments of the present application.

[0128] First, in the embodiments of the present application, "used for indication" may include being used for direct indication and being used for indirect indication. When describing that a certain "indication information" is used to indicate A, it may include that the indication information directly indicates A or indirectly indicates A, but it does not mean that the indication information must carry A.

[0129] The information indicated by the indication information is called the information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated, such as but not limited to, the information to be indicated can be directly indicated, such as the information to be indicated itself or the index of the information to be indicated. The information to be indicated can also be indirectly indicated by indicating other information, wherein there is an association between the other information and the information to be indicated. It is also possible to indicate only a part of the information to be indicated, while the other parts of the information to be indicated are known or agreed in advance. For example, the indication of specific information can also be achieved with the help of the arrangement order of each piece of information agreed in advance (for example, stipulated by the protocol), thereby reducing the indication overhead to a certain extent. At the same time, the common parts of each piece of information can also be identified and indicated uniformly to reduce the indication overhead caused by indicating the same information separately.

[0130] In addition, the specific indication method may also be various existing indication methods, such as but not limited to the above-mentioned indication methods and various combinations thereof. The specific details of the various indication methods can refer to the prior art and will not be repeated herein. As can be seen from the above, for example, when it is necessary to indicate multiple information of the same type, different indication methods may be used for different information. In the specific implementation process, the desired indication method can be selected according to specific needs. The embodiment of the present application does not limit the selected indication method. In this way, the indication method involved in the embodiment of the present application should be understood to cover various methods that can enable the party to be indicated to obtain the information to be indicated.

[0131] The information to be indicated can be sent as a whole, or divided into multiple sub-information and sent separately, and the sending period and / or sending time of these sub-information can be the same or different. The specific sending method is not limited in this application. Among them, the sending period and / or sending time of these sub-information can be pre-defined, for example, pre-defined according to the protocol, or can be configured by the transmitting device by sending configuration information to the receiving device. Among them, the configuration information can include, for example, but not limited to, one or a combination of at least two of radio resource control (RRC) signaling, MAC layer signaling and physical layer signaling. Among them, MAC layer signaling, for example, includes MAC-CE; physical (PHY) layer signaling, for example, includes downlink control information (DCI).

[0132] Second, in the embodiments of the present application, the first, second and various digital numbers are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application. For example, to distinguish different indication information. For another example, the first indication information and the second indication information are only used to distinguish different areas, and their order is not limited. Those skilled in the art can understand that the words "first", "second" and the like do not limit the quantity and execution order, and the words "first", "second" and the like do not necessarily limit them to be different.

[0133] Third, in the embodiments of the present application, descriptions such as "when...", "in the case of...", "if" and "if" all mean that under certain objective circumstances, the device (such as a terminal device or an access network device) will make corresponding processing, which is not a time limit, and does not require the device (such as a terminal device or an access network device) to have a judgment action when implementing it, nor does it mean that there are other limitations.

[0134] Meanwhile, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete manner for ease of understanding.

[0135] Finally, the network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field can know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0136] The following first introduces the system architecture involved in the embodiment of the present application:

[0137] The embodiments of the present application will present various aspects, embodiments or features around a system that may include multiple devices, components, modules, etc. It should be understood and appreciated that each system may include additional devices, components, modules, etc., and / or may not include all devices, components, modules, etc. discussed in conjunction with the figures. In addition, combinations of these schemes may also be used.

[0138] See also Figure 6 , Figure 6 Schematic diagram of a communication system used in the embodiment of the present application. Figure 6 As shown, the communication system includes an access network device and a plurality of terminal devices communicating with the access network device. Optionally, the communication system may also include a core network device communicating with the access network device.

[0139] Figure 6 The communication system shown can be applied to various communication systems, such as wireless fidelity (Wi-Fi) system, vehicle to everything (V2X) communication system, device-to-device (D2D) communication system, Internet of Vehicles communication system, 4th generation (4G) mobile communication system, such as LTE system, worldwide interoperability for microwave access (WiMAX) communication system, 5G mobile communication system, such as NR system, and future communication systems, such as 6th generation (6G) mobile communication system, etc. Among them, in different networks, the core network equipment, access network equipment, and terminal equipment in the above communication system may correspond to different names. It can be understood by those skilled in the art that different devices can be divided according to functions, and the name does not limit the device itself.

[0140] Among them, the core network device referred to in the embodiment of the present application is a device deployed in the core network to provide services for terminal devices. In systems using different wireless access technologies, the names of core network devices with similar wireless communication functions may be different. For example, when the communication method of the embodiment of the present application is applied to a 5G system, the core network device can be an access and mobility management function (AMF) network element, a session management function (SMF) network element, a user plane function (UPF) network element, etc. Among them, the UPF network element processes user plane data. The AMF network element and the SMF network element process control plane signaling. When the precoding method of the embodiment of the present application is applied to an LTE system, the core network device may be a mobility management entity (MME). For the convenience of description only, in the embodiment of the present application, the above-mentioned devices that can provide services for terminal devices are collectively referred to as core network devices.

[0141] Access network equipment is a device deployed in a wireless access network to provide wireless communication functions. Access network equipment can also be called access network node, RAN node, RAN entity or access node, etc., located on the network side of the above-mentioned communication system, to help terminal equipment achieve wireless access, and has a device with wireless transceiver function or a chip or chip system that can be set in the device. The access network equipment includes but is not limited to: base station, evolved NodeB (eNodeB), access point (AP), TRP or transmission point (TP), gNB, next-generation base station in 6G mobile communication system, base station in future mobile communication system, or access node in Wi-Fi system, etc. The access network equipment can be a macro base station, a micro base station or an indoor station, a relay node or a donor node, or a wireless controller in a centralized radio access network (CRAN) scenario. The access network device may also be one or a group of antenna panels (including multiple antenna panels) of a base station in 5G, or it may also be a network node constituting a gNB, TRP or TP or a transmission measurement function (TMF), such as a central unit (CU), DU, CU-control plane (CP), CU-user plane (UP), or a radio unit (RU), a road side unit (RSU) with a base station function. Optionally, the access network device may also be a server, a wearable device, a vehicle or a vehicle-mounted device, etc. For example, the access network device in the V2X technology may be an RSU. All or part of the functions of the access network device in this application may also be implemented by software functions running on hardware, or by virtualization functions instantiated on a platform (such as a cloud platform). The access network device in this application may also be a logical node, a logical module or software that can implement all or part of the functions of the access network device. In NTN, all or part of the functional modules of the access network device may be deployed on an airborne platform or satellite, or other forms of communication equipment deployed in the sky. Accordingly, the access network device may refer to an airborne platform, a satellite, or other similar device that connects the terminal device to the core network device. The airborne platform may include at least one of the following: a satellite, a drone, or a hot air balloon.

[0142] Among them, CU and DU can be set separately, or can also be included in the same network element, such as a baseband unit (BBU). CU and DU can be divided according to logical functions (such as implemented protocol layer functions). RU may be included in a radio frequency device or a radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU) or a remote radio head (RRH). It can be understood that the access network device can be a CU node, a DU node, or a device including a CU node and a DU node. In addition, CU can be divided into an access network device in the access network RAN, and CU can also be divided into an access network device in the CN, without limitation here.

[0143] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in an open RAN (open-RAN, O-RAN) system, CU may also be called O-CU (open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. For the convenience of description, CU, CU-CP, CU-UP, DU and RU are used as examples for description in this application. Any unit of CU (or CU-CP, CU-UP), DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0144] In the embodiments of the present application, the form of the access network device is not limited. The device for realizing the function of the access network device may be the access network device; or it may be a device capable of supporting the access network device to realize the function, such as a chip system. The device may be installed in the access network device or used in conjunction with the access network device.

[0145] The terminal device may be a terminal device with transceiver functions, or may be a chip or chip system provided in the terminal device. The terminal device may also be referred to as UE, access terminal, subscriber unit, user station, mobile station (MS), mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal device in the embodiments of the present application can be a mobile phone, a cellular phone, a smart phone, a tablet computer, a wireless data card, a personal digital assistant (PDA), a wireless modem, a handset, a laptop computer, a machine type communication (MTC) terminal, a computer with wireless transceiver function, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a smart home device (for example, a refrigerator, a television, an air conditioner, an electric meter, etc.), an intelligent robot, a robotic arm, a workshop equipment, a wireless terminal in unmanned driving, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a vehicle-mounted terminal, a roadside unit with terminal function, and a wireless terminal in smart city. The terminal device of the present application may also be a vehicle-mounted module, a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip or a vehicle-mounted unit built into a vehicle as one or more components or units. The terminal device may also be other devices with terminal functions, for example, the terminal device may also be a device that functions as a terminal in D2D communication.

[0146] The embodiments of the present application do not limit the device form of the terminal. The device for realizing the function of the terminal device can be a terminal device; it can also be a device that can support the terminal device to realize the function, such as a chip system. The device can be installed in the terminal device or used in combination with the terminal device. In the embodiments of the present application, the chip system can be composed of chips, or it can include chips and other discrete devices.

[0147] exist Figure 6 In the system architecture shown, the system also includes a ground gateway and a data network (DN). Here, the interface for the terminal device to communicate with the access network device can be an air interface. The interface for the access network device to communicate with the ground gateway can be an NG interface. The interface for the ground gateway to communicate with the core network device can be an NG interface. The core network device can be connected to only one ground gateway. In this case, the access network device can be connected to the core network device through a ground gateway. Figure 6 The core network device can be connected to more than one ground gateway. At this time, the access network device can be connected to the core network device through any of the more than one ground gateways ( Figure 6 (not shown). The core network device (such as the UPF network element) can communicate with entities or network elements in the DN through an interface (such as the N6 interface).

[0148] It should be noted that the above only lists the communication methods between some network elements. Other network elements can also communicate through certain connection methods, which will not be repeated here in the embodiments of the present application.

[0149] Furthermore, Figure 7 The present invention provides a schematic diagram of a structure of an access network device based on a CU-DU separation architecture. Figure 7 As shown, by dividing the protocol stack, the access network device includes CU-CP, CU-UP and DU, CU-CP and DU can communicate through interface 1, CU-UP and DU can communicate through interface 2, and CU-CP and CU-UP can communicate through interface 3. Optionally, the access network device may be a gNB, in which case interface 1 may be an F1-C interface, interface 2 may be an F1-U interface, and interface 3 may be an E1 interface.

[0150] Among them, CU-CP is responsible for the control plane functions, including the RRC layer and the PDCP-control (control, C) layer, among which PDCP-C is mainly responsible for encryption and decryption, integrity protection, data transmission, etc. of the control plane data.

[0151] CU-UP is responsible for user plane functions, including the SDAP layer and the PDCP-user (U) layer. SDAP is mainly responsible for processing the data of the core network and mapping the flow to the bearer, and PDCP-U is mainly responsible for encryption and decryption, integrity protection, header compression, sequence number maintenance, data transmission, etc. of the data plane.

[0152] DU includes radio link control (RLC) layer, MAC layer and PHY layer. It can be seen that both CU-CP and CU-UP contain PDCP layer, RRC layer is located above PDCP layer in CU-CP, RRC message is encapsulated into PDCP data PDU after being processed by PDCP layer, PDCP data PDU can be sent by CU-CP and CU-UP respectively. PDCP control PDU is generated by PDCP-U layer and used to transmit robust header compression (ROHC) context information, etc.

[0153] The system architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. It is known to those skilled in the art that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0154] The following will be combined Figure 8 and Fig. 9 The timing advance reporting method provided in the embodiment of the present application is specifically described.

[0155] For example, Figure 8 A flow chart of a timing advance reporting method provided in an embodiment of the present application. The timing advance reporting method is based on Figure 6 The communication between the access network device and the terminal device shown in the figure is used as an example for explanation. Of course, the subject that executes the terminal device action in the method can also be a device / module in the terminal device, such as a chip, processor, processing unit, etc. in the terminal device; the subject that executes the access network device action in the method can also be a device / module in the access network device, such as a chip, processor, processing unit, etc. in the access network device, and the embodiments of the present application do not make specific limitations on this. For example, Figure 8 As shown, the timing advance reporting method includes:

[0156] S801: The access network device sends a switching command to the terminal device. Correspondingly, the terminal device receives the switching command from the access network device.

[0157] Among them, the handover command is used to instruct the terminal device to switch from the source cell to the target cell. In the embodiment of the present application, the handover of the terminal device from the source cell to the target cell can be based on RACH handover or RACH-less handover. Therefore, the handover command can carry information indicating that the terminal device initiates RACH handover from the source cell to the target cell, or information indicating that the terminal device initiates RACH-less handover from the source cell to the target cell. In other words, the access network device can configure the cell handover mode of the terminal device to be based on RACH handover or RACH-less handover through the handover command.

[0158] In addition, the switching command may include relevant information of the target cell and relevant configuration parameters required for the terminal device to access the target cell, such as information of the target cell (such as the PCI of the target cell and the frequency information corresponding to the target cell), the C-RNTI allocated by the target cell to the terminal device, the RACH resource information required to access the target cell (such as dedicated RACH resources and / or public RACH resources), or UL grant information for RACH-less switching, etc. Among them, the UL grant information is used to indicate the UL grant, and the UL grant may include at least one of the following: time-frequency resources (PUSCH resources), modulation coding scheme (MCS), new data indicator (NDI), the time to initiate uplink transmission (such as a subframe or time slot), the interval of uplink scheduling, etc. The embodiment of the present application does not limit the specific content contained in the UL grant for RACH-less switching.

[0159] For example, the switching command may be an RRC message. For example, in NR, the switching command may be an RRC reconfiguration message carrying a synchronization reconfiguration (reconfigurationWithSync) information element. In LTE, the switching command may be an RRC connection reconfiguration message carrying mobility control information (mobility control info). The embodiment of the present application does not limit the specific name of the switching command.

[0160] In the embodiment of the present application, the handover command is taken as an example to describe the process of the terminal device triggering TA reporting during the cell handover process. It should be understood that the handover command can also be replaced by other messages or signaling, and there is no limitation on this.

[0161] It should be understood that in the embodiment of the present application, when the terminal device performs cell switching, the access network device is the access network device to which the source cell belongs. In other words, after determining that the terminal device needs to perform cell switching, the access network device to which the source cell belongs sends a switching command to the terminal device to instruct the terminal device to switch from the source cell to the target cell. The process of the access network device to which the source cell belongs performing the cell switching decision can be referred to the relevant description in the existing implementation method, and no further description is given.

[0162] S802: When the switching command carries the first indication information and / or the second indication information, the terminal device triggers timing advance reporting.

[0163] Among them, the timing advance (TA) is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device (such as offsetThresholdTA), and the offset threshold of the timing advance can be used by the terminal device to compare the threshold value of the change between the currently estimated timing advance and the last reported timing advance, and the second indication information is used to indicate the terminal device to report the timing advance (such as TA-report).

[0164] In an embodiment of the present application, after receiving a handover command, the terminal device parses the handover command to determine whether the handover command carries the first indication information and / or the second indication information. In the case that the handover command carries the first indication information and / or the second indication information, the terminal device determines to trigger the timing advance report corresponding to the target cell. Otherwise, the timing advance report corresponding to the target cell is not triggered. For example, if the configured condition for triggering the timing advance report corresponding to the target cell is that the handover command carries the first indication information, thus, if the handover command received by the terminal device does not carry the first indication information, the timing advance report corresponding to the target cell is not triggered. It should be understood that the implementation of not triggering the timing advance report corresponding to the target cell should refer to the setting of the conditions for triggering the timing advance report corresponding to the target cell by the handover command, and no limitation is made to this.

[0165] Among them, triggering the reporting of the timing advance corresponding to the target cell may refer to directly reporting the timing advance corresponding to the target cell, or may refer to the terminal device being prepared to report the timing advance corresponding to the target cell, and reporting the timing advance corresponding to the target cell at a certain time thereafter. The specific time at which the terminal device reports the timing advance corresponding to the target cell can be determined according to the allocated available resources, and no limitation is made to this. It should be understood that the embodiment of the present application is for reporting the timing advance corresponding to the target cell, and the timing advance corresponding to the target cell can be determined by referring to the calculation formula of TA in the NTN scenario described above, and no further description is given to this.

[0166] In a possible design scheme, when the switching command carries the first indication information and / or the second indication information, the terminal device can immediately trigger the reporting of the timing advance corresponding to the target cell. In other words, after the terminal device receives the first indication information and / or the second indication information, it immediately triggers the reporting of the timing advance corresponding to the target cell. At this time, the terminal device can be configured for RACH-based cell switching or RACH-less-based cell switching.

[0167] In this design, in a possible scenario 1, the terminal device may only determine whether there is the first indication information in the handover command, regardless of whether there is the second indication information in the handover command, as long as there is the first indication information, the terminal device immediately triggers the reporting of the timing advance corresponding to the target cell. Alternatively, the terminal device may only determine whether there is the second indication information in the handover command, regardless of whether there is the first indication information in the handover command, as long as there is the second indication information, the terminal device immediately triggers the reporting of the timing advance corresponding to the target cell.

[0168] Exemplarily, if the RRCReconfiguration message (switching command) carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA (first indication information), and TA has not been reported in the current serving cell, the terminal device immediately triggers TA (TA corresponding to the target cell) reporting. Alternatively, if the switching command received by the terminal device carries offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device immediately triggers TA (TA corresponding to the target cell) reporting. Optionally, the current serving cell refers to the target cell.

[0169] As another example, if the RRCReconfiguration message (switching command) carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA (first indication information), the terminal device immediately triggers TA (TA corresponding to the target cell) reporting. Alternatively, if the switching command received by the terminal device carries offsetThresholdTA, the terminal device immediately triggers TA (TA corresponding to the target cell) reporting.

[0170] In a possible scenario 2, after receiving the handover command, the terminal device determines that there is the first indication information in the handover command and there is no second indication information in the handover command, and the terminal device immediately triggers the reporting of the timing advance corresponding to the target cell. At this time, the terminal device needs to determine that there is the first indication information in the handover command and there is no second indication information before it can immediately trigger the reporting of the timing advance corresponding to the target cell.

[0171] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA, does not carry TA-report, and TA has not been reported in the current serving cell, the terminal device immediately triggers the TA report corresponding to the target cell. Alternatively, if the switching command received by the terminal device carries offsetThresholdTA, does not carry TA-report, and TA has not been reported in the current serving cell, the terminal device immediately triggers the TA report corresponding to the target cell. Optionally, the current serving cell refers to the target cell.

[0172] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA but does not carry TA-report, the terminal device immediately triggers the TA report corresponding to the target cell. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA but does not carry TA-report, the terminal device immediately triggers the TA report corresponding to the target cell.

[0173] Alternatively, the terminal device receives a handover command, determines that there is no first indication information in the handover command, and there is second indication information in the handover command, and the terminal device immediately triggers the reporting of the timing advance corresponding to the target cell. At this time, the terminal device needs to determine that there is the second indication information in the handover command and there is no first indication information before it can immediately trigger the reporting of the timing advance corresponding to the target cell.

[0174] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries a TA-report but does not carry offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device immediately triggers a TA report corresponding to the target cell. Alternatively, if the switching command received by the terminal device carries a TA-report but does not carry offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device immediately triggers a TA report corresponding to the target cell. Optionally, the current serving cell refers to the target cell.

[0175] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries TA-report but does not carry offsetThresholdTA, the terminal device immediately triggers the TA report corresponding to the target cell. Alternatively, if the handover command received by the terminal device carries TA-report but does not carry offsetThresholdTA, the terminal device immediately triggers the TA report corresponding to the target cell.

[0176] In a possible scenario 3, after receiving the switching command, the terminal device immediately triggers reporting of the timing advance corresponding to the target cell when it determines that the switching command contains both the first indication information and the second indication information.

[0177] Exemplarily, the terminal device is configured for RACH-less based cell switching. If the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, and TA has not been reported in the current serving cell, the terminal device immediately triggers the TA report corresponding to the target cell. Alternatively, the terminal device is configured for RACH-less based cell switching. If the switching command received by the terminal device carries TA-report and offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device immediately triggers the TA report corresponding to the target cell. Optionally, the current serving cell refers to the target cell.

[0178] As another example, if the terminal device is configured for RACH-less based cell switching, and if the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, the terminal device immediately triggers the TA report corresponding to the target cell. Alternatively, if the terminal device is configured for RACH-less based cell switching, and if the switching command received by the terminal device carries TA-report and offsetThresholdTA, the terminal device immediately triggers the TA report corresponding to the target cell.

[0179] In an embodiment of the present application, the above-mentioned immediate trigger may mean that when the terminal device receives the above-mentioned switching command, the terminal device triggers the TA reporting of the target cell.

[0180] In another possible design scheme, when the switching command carries the first indication information and / or the second indication information, the terminal device may not immediately trigger the reporting of the timing advance corresponding to the target cell, but may trigger the reporting of the timing advance corresponding to the target cell in a subsequent process or at a certain moment.

[0181] When the terminal device is configured for random access-based cell switching (or the terminal device is RACH-based cell switching), the terminal device may trigger reporting of the timing advance based on the following situations:

[0182] In a possible scenario 1, if the switching command carries the first indication information, the terminal device triggers the reporting of the timing advance corresponding to the target cell during the process of randomly accessing the target cell, or the terminal device triggers the reporting of the timing advance corresponding to the target cell after successfully randomly accessing the target cell.

[0183] At this time, it can be considered that the terminal device confirms that the handover command only carries the first indication information and no second indication information, or it can be considered that the terminal device only determines whether the handover command contains the first indication information, and in the case of the first indication information, it does not matter whether the handover command contains the second indication information. Thus, the terminal device triggers the reporting of the timing advance corresponding to the target cell during the random access process or after the random access is completed.

[0184] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Optionally, the current serving cell refers to the target cell.

[0185] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends.

[0186] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA but does not carry TA-report, and TA has not been reported in the current serving cell, the terminal device triggers a TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA but does not carry TA-report, and TA has not been reported in the current serving cell, the terminal device triggers a TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Optionally, the current serving cell refers to the target cell.

[0187] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA but does not carry TA-report, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA but does not carry TA-report, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends.

[0188] In a possible scenario 2, if the handover command carries the first indication information and the second indication information, the terminal device triggers the reporting of the timing advance corresponding to the target cell during the process of random access to the target cell, or the terminal device triggers the reporting of the timing advance corresponding to the target cell after the random access to the target cell is successful. At this time, the terminal device needs to determine that the handover command contains both the first indication information and the second indication information in order to trigger the reporting of the timing advance corresponding to the target cell.

[0189] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the switching command received by the terminal device carries offsetThresholdTA and TA-report, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Optionally, the current serving cell refers to the target cell.

[0190] As another example, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends. Alternatively, if the handover command received by the terminal device carries offsetThresholdTA and TA-report, the terminal device triggers the TA report corresponding to the target cell during the RACH period with the target cell or after the RACH ends.

[0191] Based on the above scenario 1 or scenario 2, the terminal device triggers the target cell's corresponding timing advance report during the process of random access to the target cell (such as during RACH), which can be the terminal device triggering the target cell's corresponding timing advance report at any time between sending Msg1 and receiving Msg4, or the terminal device triggering the target cell's corresponding timing advance report at any time between sending MsgA and receiving MsgB. The terminal device triggers the target cell's corresponding timing advance report after successfully accessing the target cell (such as after RACH ends), which can be the terminal device triggering the target cell's corresponding timing advance report after receiving Msg4 or after receiving MsgB.

[0192] When the terminal device is configured for RACH-less based cell switching (or the terminal device is RACH-less based cell switching), the terminal device may trigger the reporting of the timing advance based on the following situations:

[0193] In a possible scenario 1, if the switching command carries the first indication information or the second indication information, the terminal device triggers the reporting of the timing advance corresponding to the target cell after the cell switching is completed. That is to say, as long as the switching command contains the first indication information or the second indication information, the terminal device can trigger the reporting of the timing advance corresponding to the target cell after completing the cell switching. For example, the terminal device triggers the reporting of the timing advance corresponding to the target cell when sending a switching completion message (such as an RRC reconfiguration completion message) to the access network device corresponding to the target cell. At this time, the terminal device can report the timing advance corresponding to the target cell based on the UL grant resources configured by the access network device.

[0194] In this scenario 1, the terminal device only determines whether there is the first indication information in the handover command. If there is the first indication information, the reporting of the timing advance corresponding to the target cell is triggered regardless of whether there is the second indication information in the handover command. Alternatively, the terminal device only determines whether there is the second indication information in the handover command. If there is the second indication information, the reporting of the timing advance corresponding to the target cell is triggered regardless of whether there is the first indication information in the handover command.

[0195] Exemplarily, the terminal device is configured for RACH-less based cell switching. If the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries a TA-report, and the TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching. If the switching command received by the terminal device carries a TA-report, and the TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Optionally, the current serving cell refers to the target cell.

[0196] As another example, the terminal device is configured for RACH-less based cell switching, and if the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries a TA-report, the terminal device triggers a TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching, and if the switching command received by the terminal device carries a TA-report, the terminal device triggers a TA report corresponding to the target cell after the cell switching is completed.

[0197] As another example, the terminal device is configured for RACH-less based cell switching. If the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching. If the switching command received by the terminal device carries offsetThresholdTA, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Optionally, the current serving cell refers to the target cell.

[0198] As another example, the terminal device is configured for RACH-less based cell switching, if the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching, if the switching command received by the terminal device carries offsetThresholdTA, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed.

[0199] In a possible scenario 2, if the handover command carries the first indication information and the second indication information, the terminal device triggers the reporting of the timing advance corresponding to the target cell after the cell handover is completed. That is to say, when the handover command contains both the first indication information and the second indication information, the terminal device triggers the reporting of the timing advance corresponding to the target cell after the cell handover is completed.

[0200] Exemplarily, the terminal device is configured for RACH-less based cell switching. If the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching. If the switching command received by the terminal device carries offsetThresholdTA and TA-report, and TA has not been reported in the current serving cell, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Optionally, the current serving cell refers to the target cell.

[0201] As another example, the terminal device is configured for RACH-less based cell switching, if the RRCReconfiguration message of reconfigurationWithSync received by the terminal device carries offsetThresholdTA and TA-report, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed. Alternatively, the terminal device is configured for RACH-less based cell switching, if the switching command received by the terminal device carries offsetThresholdTA and TA-report, the terminal device triggers the TA report corresponding to the target cell after the cell switching is completed.

[0202] Figure 8 The timing advance reporting method shown clarifies the process of whether the terminal device reports the timing advance corresponding to the target cell when the switching command carries a timing advance offset threshold (such as the first indication information) and / or a timing advance reporting indication (such as the second indication information), which can ensure that accurate timing advance reporting is triggered during cell switching.

[0203] The following is a detailed description of the application scenarios. Figure 8 The communication method shown is used for explanation. Among them, the access network device that sends the handover command is the source base station (the base station to which the source cell belongs), and the base station to which the target cell belongs is the target base station.

[0204] Exemplarily, in the case where the terminal device is configured for RACH-based cell switching, such as Fig. 9 As shown in (a) in FIG. 1 , the steps are as follows:

[0205] S901a: The source base station sends a handover command to the terminal device. Correspondingly, the terminal device receives the handover command from the source base station.

[0206] The handover command is used to instruct the terminal device to switch from the source cell to the target cell, and the handover command carries the first indication information or the first indication information and the second indication information, the first indication information is used to indicate the offset threshold (such as offsetThresholdTA) of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device (such as TA-report). For the description of the handover command, please refer to the relevant description in S801 above, which will not be repeated here.

[0207] S902a. The terminal device triggers the reporting of the timing advance corresponding to the target cell.

[0208] Exemplarily, after receiving a switching command, the terminal device determines that the switching command carries the first indication information or the first indication information and the second indication information, and triggers the reporting of the timing advance corresponding to the target cell during the process of initiating random access with the target base station. For example, the terminal device triggers the reporting of the timing advance corresponding to the target cell after sending Msg1 or MsgA, and the terminal device carries the timing advance corresponding to the target cell when sending Msg3 or MsgB. It should be understood that after the terminal device sends Msg1, there are other random access steps between the terminal device and the target base station, such as the target base station sending Msg2 to the terminal device, and there are subsequent random access processes after completing Msg3, until the terminal device completes access to the target cell. The specific implementation process can be found in the above. Figure 3 and Figure 4 The relevant description in is not repeated here.

[0209] As another example, after receiving the switching command, the terminal device determines that the switching command carries the first indication information or the first indication information and the second indication information, and triggers the reporting of the timing advance corresponding to the target cell.

[0210] As another example, after receiving the switching command, the terminal device determines that the switching command carries the first indication information or the first indication information and the second indication information. After the random access is completed, the terminal device triggers the reporting of the timing advance corresponding to the target cell.

[0211] As another example, in the case where the terminal device is configured for RACH-less based cell switching, as shown in FIG. Fig. 9 As shown in (b) in FIG. 1 , the steps are as follows:

[0212] S901b: The source base station sends a handover command to the terminal device. Correspondingly, the terminal device receives the handover command from the source base station.

[0213] The handover command is used to instruct the terminal device to switch from the source cell to the target cell, and the handover command carries the first indication information and / or the second indication information, the first indication information is used to indicate the offset threshold (such as offsetThresholdTA) of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device (such as TA report). For a specific description of the handover command, please refer to the relevant description in S801 above, which will not be repeated here.

[0214] After receiving the switching command, the terminal device determines that the switching command carries the first indication information and / or the second indication information, and then determines that after the cell switching is completed, such as after executing the following S902b, the timing advance corresponding to the target cell is reported.

[0215] S902b, the terminal device sends an RRC reconfiguration completion message to the target base station. Correspondingly, the target base station receives the RRC reconfiguration completion message from the terminal device.

[0216] Among them, the RRC reconfiguration completion message is used to instruct the terminal device to complete the cell switching and access the target cell. The specific implementation process can be referred to the description in the relevant prior art, which will not be described in detail. It should be understood that the embodiment of the present application exemplarily uses the RRC reconfiguration completion message to instruct the terminal device to complete the cell switching. In addition, it can also be implemented through other messages or signaling, which is not limited to this.

[0217] S903b, the terminal device sends the timing advance corresponding to the target cell to the target base station. Correspondingly, the target base station receives the timing advance corresponding to the target cell from the terminal device.

[0218] That is, after sending the RRC reconfiguration completion message, the terminal device reports the timing advance corresponding to the target cell. Exemplarily, the timing advance corresponding to the target cell can be carried in an RRC message, MAC signaling or other signaling, which is not limited.

[0219] The above scheme is defined based on the terminal device triggering the reporting of the timing advance corresponding to the target cell during the cell switching process. In addition, the embodiment of the present application can also define a mechanism for the terminal device not triggering the reporting of the timing advance corresponding to the target cell during the cell switching process, so as to clarify the issue of whether the terminal device reports the timing advance corresponding to the target cell in the existing protocol.

[0220] In one possible design scheme, a terminal device receives a switching command from an access network device, and when the switching command carries the first indication information but does not carry the second indication information, determines not to trigger reporting of the timing advance corresponding to the target cell. That is, when the terminal device determines that the switching command carries the first indication information but does not carry the second indication information, it does not trigger reporting of the timing advance corresponding to the target cell. Alternatively, once the terminal device determines that there is no second indication information in the switching command, it does not trigger reporting of the timing advance corresponding to the target cell, regardless of whether there is the first indication information. In other words, after the terminal device receives the switching command from the access network device, whether the terminal device triggers reporting of the timing advance of the target cell to the target cell only needs to consider the second indication information.

[0221] For this design, the triggering condition (2) of the TA of the three NTNs defined in the above existing protocol can be modified as follows: in a non-switching scenario, when the terminal device receives the configuration of the TA offset threshold (offsetThresholdTA), and the terminal device has not reported TA in the current serving cell, TA reporting is triggered; or modified as follows: when the terminal device receives the configuration of the TA offset threshold (offsetThresholdTA) in an RRCReconfiguration message that does not carry reconfigurationWithSync, and the terminal device has not reported TA in the current serving cell, TA reporting is triggered. In other words, TA reporting is triggered only when the RRC reconfiguration message of the non-switching command carries offsetThresholdTA, and the RRC reconfiguration message of the non-switching command can be an RRCReconfiguration message that does not carry reconfigurationWithSync.

[0222] In this design, in one possible scenario, under the condition that the source cell and the target cell belong to the same satellite corresponding to the same access network device, since the TA corresponding to the source cell is the same as the TA corresponding to the target cell, the access network device may not configure the terminal device to report the TA, that is, the access network device does not configure the second indication information (such as TA-report) for the terminal device in the handover command. At this time, when the terminal device receives the first indication information in the handover command, it may not trigger the TA report to the target cell.

[0223] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA but does not carry ta-report, and TA has not been reported in the current serving cell, the terminal device does not trigger TA reporting.

[0224] In another possible design scheme, the terminal device receives a switching command from the access network device, and when the switching command does not carry the first indication information, the terminal device determines not to trigger the timing advance reporting corresponding to the target cell.

[0225] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device does not carry offsetThresholdTA, the terminal device does not trigger TA reporting.

[0226] For this design scheme, correspondingly, the terminal device receives an RRC reconfiguration message of a non-switching command from the access network device, and the RRC reconfiguration message of the non-switching command carries the first indication information, and when the terminal device has not reported the timing advance in the current serving cell, the terminal device triggers the timing advance report. Among them, the RRC reconfiguration message of the non-switching command can be an RRCReconfiguration message that does not carry reconfigurationWithSync. At this time, the reported timing advance is the timing advance corresponding to the source cell.

[0227] Exemplarily, if the RRCReconfiguration message carrying offsetThresholdTA received by the terminal device does not carry reconfigurationWithSync, and the terminal device has not reported TA in the current serving cell, the terminal device triggers TA reporting. Alternatively, if the terminal device receives the configuration of offsetThresholdTA, and the terminal device has not reported TA in the current serving cell, the terminal device triggers TA reporting. In other words, TA reporting will be triggered only if the RRC reconfiguration message of a non-switching command carries offsetThresholdTA, and TA reporting will not be triggered if the switching command carries offsetThresholdTA.

[0228] In one possible scenario, when the handover command does not carry the second indication information and the terminal device reuses the configuration of the source cell, at this time, regardless of whether the handover command carries the first indication information, the terminal device determines that the access network device has configured the offset threshold of the timing advance corresponding to the target cell. In other words, since the terminal device reuses the configuration of the source cell, the terminal device can use the offset threshold of the timing advance corresponding to the source cell as the offset threshold of the timing advance corresponding to the target cell, and it is considered that the access network device has configured the offset threshold of the timing advance during the cell handover process.

[0229] In addition, for the triggering condition (3) of the TA of the three types of NTN defined in the above-mentioned existing protocol, the terminal device will compare the current TA estimation value with the TA reported last time (also referred to as the latest reported). However, in the cell switching scenario, the most recently reported TA may be understood as the TA most recently reported in the source cell, or it may be understood as the TA most recently reported in the target cell. Therefore, the embodiment of the present application further defines how to determine which TA is the most recently reported.

[0230] In a possible design, the trigger condition (3) of TA is modified as follows: when the change between the current TA estimation value of the terminal device and the last reported TA value (the latest reported TA) in the same cell exceeds the threshold offsetThresholdTA, TA reporting is triggered. Or it is modified as follows: when the change between the current TA estimation value of the terminal device and the last reported TA value (the latest reported TA) in the same cell and the current serving cell exceeds the threshold offsetThresholdTA, TA reporting is triggered.

[0231] In this design, for the switching scenario (i.e. when the terminal device receives a switching command), even if the change in the TA of the terminal device in the target cell exceeds the threshold offsetThresholdTA compared with the TA value last reported by the terminal device in the source cell, the terminal device does not trigger the TA report in the target cell.

[0232] In another possible design, the most recently reported TA includes the TA last reported by the terminal device in the source cell in a handover scenario, and also includes the TA last reported by the terminal device in the same cell in a non-handover scenario. For a handover scenario:

[0233] The access network device sends a handover command to the terminal device. Correspondingly, the terminal device receives the handover command from the access network device. The handover command is used to instruct the terminal device to switch from the source cell to the target cell. It should be understood that the handover command may include relevant information of the target cell and relevant configuration parameters required for the terminal device to access the target cell. For details, please refer to the relevant description in S801 above, which will not be repeated here.

[0234] In the scenario where the cell switching is an inter-station switching, that is, the source cell and the target cell correspond to different access network devices, and the terminal device accesses different access network devices, in a possible design scheme, when the switching command carries the first indication information, the terminal device determines that the last reported timing advance is the timing advance corresponding to the target cell. Among them, the first indication information is used to indicate the offset threshold (such as offsetThresholdTA) of the timing advance reported by the terminal device. That is to say, when the terminal device receives the switching command carrying the first indication information, and the change between the current timing advance estimate of the terminal device and the timing advance corresponding to the last reported target cell is greater than the offset threshold, the terminal device triggers the timing advance report. At this time, the reported timing advance is the timing advance corresponding to the target cell.

[0235] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA, and the change between the current TA estimation value and the latest reported TA value of the target cell is greater than the threshold offsetThresholdTA, TA reporting is triggered.

[0236] Correspondingly, when the first indication information is not carried in the handover command, but is carried in other signaling or messages, the terminal device determines that the last reported timing advance is the timing advance corresponding to the source cell. In this case, the first indication information may be carried in an RRC reconfiguration message other than a handover command (such as an RRC reconfiguration message that does not carry reconfigurationWithSync). That is, when the terminal device receives the first indication information, and the change between the current timing advance estimate of the terminal device and the timing advance corresponding to the last reported source cell is greater than the offset threshold, the terminal device triggers the timing advance report. At this time, the reported timing advance is the timing advance corresponding to the source cell.

[0237] Exemplarily, if the terminal device receives the configuration of offsetThresholdTA, and the change between the current TA estimation value and the latest reported TA value of the source cell is greater than the threshold offsetThresholdTA, the terminal device triggers TA reporting; or, if the terminal device receives the configuration of offsetThresholdTA in an RRCReconfiguration message that does not carry reconfigurationWithSync, and the change between the current TA estimation value and the latest reported TA value of the source cell is greater than the threshold offsetThresholdTA, the terminal device triggers TA reporting.

[0238] In the scenario where the cell switching is an intra-site switching, that is, the source cell and the target cell correspond to the same access network device, and the terminal device accesses the same access network device, in a possible design scheme, when the switching command carries the first indication information, the terminal device determines that the last reported timing advance is the timing advance corresponding to the source cell. That is to say, when the terminal device receives the switching command carrying the first indication information, and the change between the current timing advance estimate of the terminal device and the timing advance corresponding to the last reported source cell is greater than the offset threshold, the terminal device triggers the timing advance report.

[0239] Exemplarily, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA, and the change between the current TA estimation value and the latest reported TA value of the source cell is greater than the threshold offsetThresholdTA, the terminal device triggers TA reporting.

[0240] In another possible design, the trigger condition (3) of the TA of the existing protocol is only for non-handover scenarios, and the new indication information can be used to control whether to compare the current timing advance estimate with the timing advance corresponding to the source cell to trigger the reporting of TA to the target cell. For example, the trigger condition (3) can be modified as follows: in a non-handover scenario (for example, no RRCReconfiguration message carrying reconfigurationWithSync is received), when the change in the current TA estimate of the terminal device compared with the last reported TA value (the latest reported TA) exceeds the threshold offsetThresholdTA, TA reporting is triggered.

[0241] In a handover scenario (for example, when an RRCReconfiguration message carrying reconfigurationWithSync is received), the terminal device determines, according to the third indication information, whether to trigger TA reporting in the target cell when the change in the current TA estimate value compared to the last reported TA value of the source cell (the latest reported TA) exceeds the threshold offsetThresholdTA, specifically:

[0242] The access network device sends a handover command to the terminal device. Accordingly, the terminal device receives the handover command from the access network device. The handover command is used to instruct the terminal device to switch from the source cell to the target cell, and the handover command carries the third indication information, and the third indication information is used to indicate whether the terminal device compares the current timing advance estimate with the timing advance corresponding to the source cell, or to indicate whether to trigger the timing advance report in the target cell when the change amount of the current timing advance estimate compared with the timing advance of the source cell reported last time (the latest reported TA) exceeds the offset threshold (threshold offsetThresholdTA). Thus, the terminal device determines whether the current timing advance estimate of the terminal device is compared with the timing advance corresponding to the source cell according to the third indication information, or determines whether to trigger the timing advance report in the target cell when the change amount of the current timing advance estimate compared with the timing advance of the source cell reported last time (the latest reported TA) exceeds the offset threshold (threshold offsetThresholdTA). It should be understood that the handover command may also carry the first indication information to indicate the offset threshold of the timing advance.

[0243] When the third indication information is used to indicate a threshold comparison between the current timing advance estimate of the terminal device and the timing advance corresponding to the source cell, the terminal device compares the change between the current timing advance estimate and the timing advance corresponding to the last reported source cell with the offset threshold. When the change between the current timing advance estimate and the timing advance corresponding to the last reported source cell is greater than the offset threshold, the terminal device triggers the timing advance reporting.

[0244] Alternatively, when the third indication information is used to indicate that the timing advance report in the target cell is triggered when the change between the current timing advance estimate and the timing advance corresponding to the last reported source cell (the latest reported TA) exceeds the offset threshold, if the change between the current timing advance estimate and the timing advance corresponding to the last reported source cell is greater than the offset threshold, the terminal device triggers the timing advance report in the target cell.

[0245] Thus, the access network device can configure the last reported timing advance of the terminal device as the timing advance corresponding to the source cell in the switching command. That is to say, when the terminal device receives a switching command carrying the third indication information, and the third indication information is used to indicate the threshold comparison between the current timing advance estimate and the timing advance corresponding to the source cell, if the change between the current timing advance estimate of the terminal device and the last reported timing advance corresponding to the source cell is greater than the offset threshold, the terminal device triggers the timing advance report. At this time, the reported timing advance is the timing advance corresponding to the target cell.

[0246] Alternatively, when the terminal device receives a switching command carrying the third indication information, and the third indication information is used to indicate that the change between the current timing advance estimate and the timing advance of the source cell reported last time exceeds the offset threshold, the timing advance report in the target cell is triggered, and if the change between the current timing advance estimate of the terminal device and the timing advance corresponding to the source cell reported last time is greater than the offset threshold, the terminal device triggers the timing advance report. At this time, the reported timing advance is the timing advance corresponding to the target cell.

[0247] Exemplarily, taking the third indication information as indication as an example, if the third indication information is used to indicate that the current TA estimation value of the terminal device is compared with the TA value corresponding to the source cell for a threshold comparison or is used to indicate that the change in the current TA estimation value compared with the TA value of the source cell reported last time exceeds the threshold offsetThresholdTA, triggering TA reporting in the target cell, then the third indication information is indicated as indication-y; if the third indication information is used to indicate that the current TA estimation value of the terminal device is compared with the TA value corresponding to the target cell for a threshold comparison or is used to indicate that the change in the current TA estimation value compared with the TA value of the source cell reported last time (the latest reported TA) in the source cell exceeds the threshold offsetThresholdTA, not triggering TA reporting in the target cell, then the third indication information is indicated as indication-n or the switching command does not carry indication-y. Therefore, if the RRCReconfiguration message carrying reconfigurationWithSync received by the terminal device carries offsetThresholdTA and indication-y, and the change between the current TA estimation value and the latest reported TA value of the source cell is greater than the threshold offsetThresholdTA, the terminal device triggers TA reporting.

[0248] It can be understood that in each of the above embodiments, the methods and / or steps implemented by the terminal device can also be implemented by components that can be used for the terminal device (such as a processor, chip, chip system, circuit, logic module, or software); the methods and / or steps implemented by the access network device can also be implemented by components that can be used for the access network device (such as a processor, chip, chip system, circuit, logic module, or software).

[0249] The above mainly introduces the scheme provided by the present application. Accordingly, the present application also provides a communication device, which is used to implement various methods in the above method embodiments. The communication device can be a terminal device in the above method embodiments, or a device including a terminal device, or a component that can be used for a terminal device, such as a chip or a chip system. Alternatively, the communication device can be an access network device in the above method embodiments, or a device including an access network device, or a component that can be used for an access network device, such as a chip or a chip system.

[0250] It is understandable that, in order to realize the above functions, the communication device includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0251] The embodiment of the present application can divide the functional modules of the communication device according to the above method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0252] Taking the communication device as the terminal device or access network device in the above method embodiment as an example, Fig.10 Schematic diagram of a communication device provided in an embodiment of the present application. Fig.10 As shown, the communication device 1000 includes: a processing module 1001 and a transceiver module 1002. The processing module 1001 is used to perform the processing function of the terminal device or access network device in the above method embodiment. The transceiver module 1002 is used to perform the transceiver function of the terminal device or access network device in the above method embodiment.

[0253] Among them, all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0254] Since the communication device 1000 provided in this embodiment can execute the above method, the technical effects that can be obtained can refer to the above method embodiments and will not be repeated here.

[0255] In a possible design scheme, in the embodiment of the present application, the transceiver module 1002 may include a receiving module and a sending module ( Fig.10 The transceiver module is used to implement the sending function and the receiving function of the communication device 1000.

[0256] In a possible design solution, the communication device 1000 may further include a storage module ( Fig.10 (not shown in the figure), the storage module stores a program or instruction. When the processing module 1001 executes the program or instruction, the communication device 1000 can execute Figure 8 or Fig. 9 Functions of the terminal device or access network device in the method shown.

[0257] It should be understood that the processing module 1001 involved in the communication device 1000 can be implemented by a processor or a processor-related circuit component, which can be a processor or a processing unit; the transceiver module 1002 can be implemented by a transceiver or a transceiver-related circuit component, which can be a transceiver or a transceiver unit.

[0258] For example, Fig.11 This is a schematic diagram of the structure of another communication device provided in an embodiment of the present application. The communication device may be a terminal device or an access network device, or may be a chip (system) or other components or assemblies that can be set in the terminal device or the access network device. Fig.11 As shown, the communication device 1100 may include a processor 1101. In a possible design, the communication device 1100 may further include a memory 1102 and / or a transceiver 1103. The processor 1101 is coupled to the memory 1102 and the transceiver 1103, for example, via a communication bus.

[0259] Combine the following Fig.11 The components of the communication device 1100 are described in detail:

[0260] The processor 1101 is the control center of the communication device 1100, and may be a processor or a general term for multiple processing elements. For example, the processor 1101 is one or more central processing units (CPUs), or may be application specific integrated circuits (ASICs), or may be configured to implement one or more integrated circuits of the embodiments of the present application, such as one or more microprocessors (digital signal processors, DSPs), or one or more field programmable gate arrays (FPGAs).

[0261] In one possible design, the processor 1101 may execute various functions of the communication device 1100 by running or executing a software program stored in the memory 1102 and calling data stored in the memory 1102 .

[0262] In a specific implementation, as an embodiment, the processor 1101 may include one or more CPUs, such as Fig.11 CPU0 and CPU1 are shown in FIG.

[0263] In a specific implementation, as an embodiment, the communication device 1100 may also include multiple processors, such as Fig.11 1 and 1104. Each of these processors may be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). A processor herein may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0264] The memory 1102 is used to store the software program for executing the solution of the present application, and the execution is controlled by the processor 1101. The specific implementation method can refer to the above method embodiment, which will not be repeated here.

[0265] In a possible design, the memory 1102 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 1102 may be integrated with the processor 1101, or may exist independently and access the computer through the interface circuit ( Fig.11 1101) is coupled to the processor 1101, which is not specifically limited in the embodiments of the present application.

[0266] The transceiver 1103 is used for communication with other communication devices. For example, the communication device 1100 is a terminal device, and the transceiver 1103 can be used to communicate with an access network device, or with another terminal device. For another example, the communication device 1100 is an access network device, and the transceiver 1103 can be used to communicate with a terminal device, or with another access network device.

[0267] In one possible design, transceiver 1103 may include a receiver and a transmitter ( Fig.11 The receiver is used to implement a receiving function, and the transmitter is used to implement a sending function.

[0268] In a possible design, the transceiver 1103 may be integrated with the processor 1101, or may exist independently and communicate with the processor 1101 through the interface circuit ( Fig.11 1101) is coupled to the processor 1101, which is not specifically limited in the embodiments of the present application.

[0269] It should be noted that Fig.11 The structure of the communication device 1100 shown in the figure does not constitute a limitation on the communication device. The actual communication device may include more or fewer components than those shown in the figure, or combine certain components, or arrange the components differently.

[0270] In addition, the technical effects of the communication device 1100 can refer to the technical effects of the method described in the above method embodiment, which will not be repeated here.

[0271] The embodiment of the present application also provides a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed by a computer, the functions of the above-mentioned method embodiment are realized.

[0272] The embodiment of the present application also provides a computer program product, which implements the functions of the above method embodiment when executed by a computer.

[0273] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loading and executing computer program instructions on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server, data center, etc. that contains one or more servers that can be integrated with a medium. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state disk (SSD)).

[0274] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0275] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0276] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0277] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0278] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0279] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or an access network device, etc.) to perform all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0280] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art may understand and implement other changes to the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0281] Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A timing advance reporting method, characterized in that: The method comprises: Receiving a handover command from an access network device, the handover command being used to instruct a terminal device to handover from a source cell to a target cell; When the switching command carries the first indication information and / or the second indication information, the timing advance reporting is triggered; wherein the timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device.

2. The method according to claim 1, characterized in that In a case where the handover command carries the first indication information and / or the second indication information, triggering the timing advance reporting includes: If the handover command carries the first indication information, the timing advance reporting is triggered during the process of randomly accessing the target cell or after the random access to the target cell is successful.

3. The method according to claim 1, characterized in that: In a case where the handover command carries the first indication information and / or the second indication information, triggering the timing advance reporting includes: If the handover command carries the first indication information and the second indication information, the timing advance reporting is triggered during the process of randomly accessing the target cell or after the random access to the target cell is successful.

4. The method according to claim 1, characterized in that: In a case where the handover command carries the first indication information and / or the second indication information, triggering the timing advance reporting includes: In the case where the terminal device is configured for cell switching based on a random access channel-less RACH, if the switching command carries the first indication information and / or the second indication information, the timing advance reporting is triggered after the cell switching is completed.

5. A timing advance reporting method, characterized in that: The method comprises: Receiving a radio resource control (RRC) reconfiguration message from an access network device, where the RRC reconfiguration message is used to instruct the terminal device to switch from a source cell to a target cell; In a case where the RRC reconfiguration message carries the first indication information but does not carry the second indication information, it is determined that the timing advance reporting is not triggered; wherein the timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device.

6. The method according to claim 5, characterized in that The RRC reconfiguration message carries synchronization reconfiguration.

7. A communication device, characterized in that: include: Processing module and transceiver module; wherein, The transceiver module is used to receive a handover command from an access network device, where the handover command is used to instruct the terminal device to handover from a source cell to a target cell; The processing module is used to trigger the reporting of the timing advance when the switching command carries the first indication information and / or the second indication information; wherein the timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device.

8. The device according to claim 7, characterized in that The processing module is configured to trigger the reporting of the timing advance when the handover command carries the first indication information and / or the second indication information, including: If the handover command carries the first indication information, the processing module is used to trigger the reporting of the timing advance during the process of randomly accessing the target cell or after the random access to the target cell is successful.

9. The device according to claim 7, characterized in that The processing module is configured to trigger the reporting of the timing advance when the handover command carries the first indication information and / or the second indication information, including: If the handover command carries the first indication information and the second indication information, the processing module is used to trigger the reporting of the timing advance during the process of randomly accessing the target cell or after the random access to the target cell is successful.

10. The device according to claim 7, characterized in that The processing module is configured to trigger the reporting of the timing advance when the handover command carries the first indication information and / or the second indication information, including: In the case where the terminal device is configured for cell switching based on a random access channel RACH-less, if the switching command carries the first indication information and / or the second indication information, the processing module is used to trigger the timing advance reporting after the cell switching is completed.

11. A communication device, characterized in that: include: Processing module and transceiver module; wherein, The transceiver module is used to receive a handover command from an access network device, where the handover command is used to instruct the terminal device to handover from a source cell to a target cell; The processing module is used to determine not to trigger the reporting of the timing advance when the switching command carries the first indication information but does not carry the second indication information; wherein the timing advance is the timing advance corresponding to the target cell, the first indication information is used to indicate the offset threshold of the timing advance reported by the terminal device, and the second indication information is used to indicate the timing advance reported by the terminal device.

12. The device according to claim 11, characterized in that The handover command is a radio resource control RRC reconfiguration message carrying synchronization reconfiguration.

13. A communication device, characterized in that: It includes a processor and an interface circuit, wherein the interface circuit is used to receive signals from other communication devices outside the communication device and transmit them to the processor or send signals from the processor to other communication devices outside the communication device, and the processor is used to implement the method as described in any one of claims 1 to 6 through a logic circuit or executing code instructions.

14. A communication device, characterized in that: include: A processor, wherein the processor is configured to execute a computer program so that the communication device executes the method according to any one of claims 1 to 6.

15. A communication chip, characterized in that: Instructions are stored therein, and when the chip is run on a communication device, the method according to any one of claims 1 to 6 is implemented.

16. A computer-readable storage medium, characterized in that: The storage medium stores a computer program or instruction. When the computer program or instruction is executed by the communication device, the method according to any one of claims 1 to 6 is implemented.

17. A computer program product, characterized in that The device comprises a computer program code. When the computer program code is executed on a communication device, the communication device implements the method according to any one of claims 1 to 6.

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