Communication method, terminal, network device, system, and storage medium

Abstract

The present disclosure provides a communication method, a terminal, a network device, a system, and a storage medium. The method comprises: receiving a first media access control element (MAC CE) sent by a network device, wherein the first MAC CE is used for configuring a timing advance (TA) corresponding to conditional Layer 1 / Layer 2 triggered mobility (CLTM); and on the basis of the first MAC CE, maintaining the TA corresponding to the CLTM. The present disclosure provides support for multiple transmission and reception points (TRPs), and reduces the delay of executing LTM, especially CLTM.

Description

Communication methods, terminals, network devices, systems, and storage media Technical Field

[0001] This disclosure relates to the field of communications, and in particular to communication methods, terminals, network devices, systems and storage media. Background Technology

[0002] Layer 1 / L2 Triggered Mobility (LTM) refers to the process by which a network device triggers a cell switch between a primary cell (or cell group) (PCell) and / or a primary secondary cell (PSCell) based on measurements from Layer 1 (L1) and / or Layer 2 (L2). Summary of the Invention

[0003] To reduce the latency of performing LTM, especially mobility CLTM triggered by condition layer 1 and layer 2, embodiments of this disclosure provide a communication method, terminal, network device, system, and storage medium.

[0004] According to a first aspect of the present disclosure, a communication method is provided, the method being executed by a terminal, the method comprising:

[0005] The network device receives a first media access control unit (MAC CE) sent by the network device. The first MAC CE is used to configure the timing advance (TA) corresponding to the mobility CLTM triggered by condition layer 1 and layer 2.

[0006] Based on the first MAC CE, maintain the TA corresponding to CLTM.

[0007] According to a second aspect of the present disclosure, a communication method is provided, the method being performed by a network device, the method comprising:

[0008] Send a first Media Access Control Unit (MAC CE) to the terminal. The first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by Conditional Layer 1 and Layer 2. The first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

[0009] According to a third aspect of the present disclosure, a terminal is provided, comprising:

[0010] The transceiver module is configured to receive a first media access control unit (MAC CE) sent by a network device. The first MAC CE is used to configure the timing advance (TA) corresponding to the mobility CLTM triggered by conditional layer 1 or layer 2.

[0011] The processing module is configured to maintain the TA corresponding to the CLTM based on the first MAC CE.

[0012] According to a fourth aspect of the present disclosure, a network device is provided, comprising:

[0013] The transceiver module is configured to send a first media access control unit (MAC CE) to the terminal. The first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by condition layer 1 and layer 2. The first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

[0014] According to a fifth aspect of the present disclosure, a terminal is provided, comprising:

[0015] One or more processors;

[0016] The processor is used to execute the method described in any one of the first aspects.

[0017] According to a sixth aspect of the present disclosure, a network device is provided, comprising:

[0018] One or more processors;

[0019] The processor is used to execute the communication method described in any one of the second aspects.

[0020] According to a seventh aspect of the present disclosure, a communication system is provided, comprising:

[0021] A terminal, the terminal being configured to implement the communication method described in any one of the first aspects;

[0022] A network device configured to implement the communication method described in any one of the second aspects.

[0023] According to an eighth aspect of the present disclosure, a storage medium is provided that stores instructions that, when executed on a communication device, cause the communication device to perform a communication method as described in any one of the first or second aspects.

[0024] According to a ninth aspect of the present disclosure, a computer program product is provided, including a computer program that, when executed by a processor, is used to implement the communication method described in any one of the first or second aspects.

[0025] In this embodiment of the disclosure, the terminal can maintain the TA corresponding to CLTM based on the first MAC CE sent by the network device, thereby realizing support for multiple transmission receiver points (TRP) and reducing the latency of executing LTM, especially CLTM.

[0026] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0028] Figure 1A is a schematic diagram of the structure of a communication system according to an exemplary embodiment.

[0029] Figure 1B is a schematic diagram of an intra-gNB LTM process according to an exemplary embodiment.

[0030] Figure 1C is a schematic diagram of a process based on contention-free random access (FDRA) according to an exemplary embodiment.

[0031] Figure 2 is an interactive schematic diagram of a communication method according to an exemplary embodiment.

[0032] Figure 3A is a flowchart illustrating one of the communication methods according to an exemplary embodiment.

[0033] Figure 3B is a second schematic flowchart illustrating a communication method according to an exemplary embodiment.

[0034] Figure 4A is a schematic diagram of the structure of a MAC CE according to an exemplary embodiment.

[0035] Figure 4B is a second schematic diagram of a MAC CE structure according to an exemplary embodiment.

[0036] Figure 4C is a third schematic diagram of a MAC CE structure according to an exemplary embodiment.

[0037] Figure 4D is a schematic diagram of the structure of a MAC CE according to an exemplary embodiment.

[0038] Figure 4E is a fifth schematic diagram of the structure of a MAC CE according to an exemplary embodiment.

[0039] Figure 5A is a schematic diagram of the structure of a terminal according to an exemplary embodiment.

[0040] Figure 5B is a schematic diagram of the structure of a network device according to an exemplary embodiment.

[0041] Figure 6A is a schematic diagram of the structure of a communication device according to an exemplary embodiment.

[0042] Figure 6B is a schematic diagram of the structure of a chip according to an exemplary embodiment. Detailed Implementation

[0043] This disclosure provides a communication method, terminal, network device, system, and storage medium.

[0044] In a first aspect, embodiments of this disclosure propose a communication method executed by a terminal, the method comprising: receiving a first Media Access Control Unit (MAC CE) sent by a network device, the first MAC CE being used to configure a timing advance amount (TA) corresponding to a mobility CLTM triggered by a Conditional Layer 1 or Layer 2; and maintaining the TA corresponding to the CLTM based on the first MAC CE.

[0045] In the above embodiments, the terminal can maintain the TA corresponding to CLTM based on the first MAC CE sent by the network device, thereby realizing support for multiple transmission receiver points (TRP) and reducing the latency of executing LTM, especially CLTM.

[0046] In conjunction with some embodiments of the first aspect, in some embodiments, the first MAC CE includes first information, the first information being used to indicate at least one of the following: a Transmission Configuration Indicator (TCI) status identifier corresponding to each TA; and a timing advance group (TAG) identifier to which the TA belongs.

[0047] In the above embodiments, the terminal can determine the correspondence between the TA and the beam based on the first information, or determine the TAG to which the TA belongs. This expands the field information of CLTM TA MAC CE, eliminating the need to indicate the above content through separate indication information, and effectively saving the signaling resources of the network device.

[0048] In conjunction with some embodiments of the first aspect, in some embodiments, when the bit value of the first information is a first value, the TA belongs to a first TAG; and / or when the bit value of the first information is a second value, the TA belongs to a second TAG.

[0049] In the above embodiments, the TAG to which the TA belongs can be indicated with fewer bits in the MAC CE, thus saving the signaling resources of the MAC CE.

[0050] In some embodiments, in conjunction with the first aspect, the method further includes: receiving second information sent by the network device, the second information being used to determine the first value and / or the second value.

[0051] In the above embodiments, the terminal can determine the first value and / or the second value based on the second information sent by the network device, thereby quickly determining the TAG indicated by the first information and ensuring the accuracy of the TA corresponding to the maintained CLTM.

[0052] In conjunction with some embodiments of the first aspect, in some embodiments, maintaining the TA corresponding to the CLTM includes at least one of the following: maintaining the TA corresponding to the CLTM for each candidate cell; maintaining the TA corresponding to the CLTM for different beams of each candidate cell; and maintaining different TAs corresponding to the CLTM within each candidate cell.

[0053] In the above embodiments, the terminal can maintain the TA corresponding to CLTM according to different granularities, thereby improving the efficiency of executing CLTM.

[0054] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes at least one of the following: activating a first TCI state based on the first MAC CE; deactivating a second TCI state based on the first MAC CE, wherein the second TCI state is different from the first TCI state and belongs to any candidate cell; wherein the first TCI state is the TCI state activated by the first MAC CE.

[0055] In the above embodiments, the first MAC CE can be used to activate or deactivate different TCI states without having to send a separate MAC CE to activate or deactivate the TCI state, thus saving MAC CE signaling resources.

[0056] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: determining to execute a first type of CLTM based on the TA corresponding to the maintained CLTM, wherein the first type of CLTM does not require triggering a random access procedure.

[0057] In the above embodiments, the terminal can determine to execute the first type of CLTM based on the TA corresponding to the maintained CLTM. Since it does not require triggering a random access procedure, the latency of executing CLTM can be further reduced.

[0058] In conjunction with some embodiments of the first aspect, in some embodiments, determining to execute a first type of CLTM based on the TA corresponding to the maintained CLTM includes any one of the following: If a first TA is valid and the beam associated with the first TA includes a first beam, then the first type of CLTM is determined to be executed, where the first TA is the TA corresponding to the target cell of the CLTM; If a second TA is valid and the TAG indicated by the first information includes the second TA, then the first type of CLTM is determined to be executed, where the first TA is valid, where the first TA is the TA corresponding to the target cell of the CLTM; If a second TA is valid, then the first type of CLTM is determined to be executed, where the second TA is the TA corresponding to the first beam, where the second TA is the TA corresponding to the first beam, when different TAs corresponding to the CLTM within each candidate cell are maintained separately; If a second TA is valid, then the first type of CLTM is determined to be executed, where the second TA is the TA corresponding to the first beam, and the first beam is the beam that satisfies the CLTM execution conditions.

[0059] In the above embodiments, the terminal can accurately determine whether the first type of CLTM can be executed by using the above method, thereby improving the accuracy of executing the first type of CLTM.

[0060] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: sending capability information to the network device, the capability information indicating at least one of the following: a first quantity, the first quantity being the maximum number of TAs corresponding to the CLTM maintained by the terminal; a second quantity, the second quantity being the maximum number of TAs supported by the terminal; a third quantity, the third quantity being the maximum number of TAs corresponding to the service TAGs supported by the terminal; whether the candidate cells of the CLTM support multiple TAs; and the maximum number of candidate cells of the CLTM supporting multiple TAs.

[0061] In the above embodiments, the terminal can report its capabilities to the network device, thereby improving the reliability and flexibility of configuring the number of TAs corresponding to CLTM on the network device.

[0062] Secondly, embodiments of this disclosure propose a communication method executed by a network device, the method comprising: sending a first media access control unit (MAC CE) to a terminal, wherein the first MAC CE is used to configure a timing advance amount (TA) corresponding to a mobility CLTM triggered by a conditional layer 1 or layer 2; wherein the first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

[0063] In conjunction with some embodiments of the second aspect, in some embodiments, the first MAC CE includes first information, which is used to indicate at least one of the following: the Transmission Configuration Indicator (TCI) status identifier corresponding to each TA; and the timing advance group (TAG) identifier to which the TA belongs.

[0064] In conjunction with some embodiments of the second aspect, in some embodiments, when the bit value of the first information is a first value, the TA belongs to a first TAG; and / or when the bit value of the first information is a second value, the TA belongs to a second TAG.

[0065] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: receiving second information sent by the network device, the second information being used to determine the first value and / or the second value.

[0066] In conjunction with some embodiments of the second aspect, in some embodiments, the first MAC CE is used for at least one of the following: activating a first TCI state; deactivating a second TCI state, the second TCI state being different from the first TCI state and belonging to any candidate cell; wherein the first TCI state is the TCI state activated by the first MAC CE.

[0067] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: receiving capability information sent by the terminal, the capability information indicating at least one of the following: a first quantity, the first quantity being the maximum number of TAs corresponding to the CLTM supported by the terminal; a second quantity, the second quantity being the maximum number of TAs supported by the terminal; a third quantity, the third quantity being the maximum number of TAs corresponding to the service TAG supported by the terminal; whether the candidate cells of the CLTM support multiple TAs; and the maximum number of candidate cells of the CLTM supporting multiple TAs.

[0068] Thirdly, embodiments of this disclosure provide a terminal, including: a transceiver module configured to receive a first media access control unit (MAC CE) sent by a network device, wherein the first MAC CE is used to configure a timing advance amount (TA) corresponding to a mobility CLTM triggered by a conditional layer 1 or layer 2; and a processing module configured to maintain the TA corresponding to the CLTM based on the first MAC CE.

[0069] Fourthly, embodiments of this disclosure provide a network device, including: a transceiver module configured to send a first media access control unit (MAC CE) to a terminal, wherein the first MAC CE is used to configure a timing advance amount (TA) corresponding to a mobility CLTM triggered by a conditional layer 1 or layer 2; wherein the first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

[0070] Fifthly, embodiments of this disclosure provide a terminal comprising: one or more processors; wherein the processors are configured to execute the communication method described in any one of the first aspects.

[0071] In a sixth aspect, embodiments of this disclosure provide a network device comprising: one or more processors; wherein the processors are configured to perform the communication method described in any one of the second aspects.

[0072] In a seventh aspect, embodiments of this disclosure provide a communication system comprising: a terminal configured to perform the communication method described in any one aspect; and a network device configured to perform the communication method described in any one aspect.

[0073] Eighthly, embodiments of this disclosure provide a storage medium storing instructions that, when executed on a communication device, cause the communication device to perform the communication method as described in either the first or second aspect.

[0074] In a ninth aspect, embodiments of this disclosure provide a computer program product, including a computer program that, when executed by a processor, is used to implement the communication method described in any one of the first or second aspects.

[0075] It is understood that the aforementioned terminals, network devices, communication systems, and storage media are all used to execute the methods proposed in the embodiments of this disclosure. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods, and will not be repeated here.

[0076] This disclosure provides communication methods, terminals, network devices, systems, and storage media. In some embodiments, the terms "communication method" and "information transmission method," "information processing method," etc., can be used interchangeably; the terms "communication device" and "information transmission device," "information processing device," etc., can be used interchangeably; and the terms "information transmission system," "information processing system," "communication system," etc., can be used interchangeably.

[0077] This disclosure is not exhaustive, but merely illustrative of some embodiments, and is not intended to limit the scope of protection of this disclosure. Unless otherwise specified, each step in a particular embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a particular embodiment can also be implemented as an independent embodiment, and the order of the steps in a particular embodiment can be arbitrarily interchanged. Furthermore, the optional implementation methods in a particular embodiment can be arbitrarily combined; moreover, the embodiments can be arbitrarily combined, for example, some or all steps of different embodiments can be arbitrarily combined, and a particular embodiment can be arbitrarily combined with the optional implementation methods of other embodiments.

[0078] In each of the disclosed embodiments, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of the embodiments are consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0079] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the scope of this disclosure.

[0080] In this disclosure, unless otherwise stated, elements expressed in the singular form, such as "a," "an," "the," "the aforementioned," "this," etc., can mean "one and only one," or "one or more," "at least one," etc. For example, when using articles such as "a," "an," "the," etc. in translation, the noun following the article can be understood as either a singular or a plural expression.

[0081] In the embodiments disclosed herein, "multiple" refers to two or more.

[0082] In some embodiments, the terms “at least one of”, “one or more”, “a plurality of”, “multiple”, etc., may be used interchangeably.

[0083] In some embodiments, the notation "at least one of A and B", "A and / or B", "A in one case, B in another", "in response to one case A, in response to another case B", etc., may include the following technical solutions depending on the situation: in some embodiments, A (execute A regardless of B); in some embodiments, B (execute B regardless of A); in some embodiments, execution is selected from A and B (A and B are selectively executed); in some embodiments, A and B (both A and B are executed). The same applies when there are more branches such as A, B, C, etc.

[0084] In some embodiments, the notation "A or B" may include the following technical solutions, depending on the situation: in some embodiments, A (execution of A regardless of B); in some embodiments, B (execution of B regardless of A); in some embodiments, execution is selected from A and B (A and B are selectively executed). The same applies when there are more branches such as A, B, C, etc.

[0085] The prefixes "first," "second," etc., used in the embodiments of this disclosure are merely for distinguishing different descriptive objects and do not impose restrictions on the position, order, priority, quantity, or content of the descriptive objects. The description of the descriptive objects is found in the claims or the context of the embodiments, and the use of prefixes should not constitute unnecessary restrictions. For example, if the descriptive object is a "field," the ordinal numbers preceding "field" in "first field" and "second field" do not restrict the position or order of the "fields." "First" and "second" do not restrict whether the "fields" they modify are in the same message, nor do they restrict the order of "first field" and "second field." Similarly, if the descriptive object is a "level," the ordinal numbers preceding "level" in "first level" and "second level" do not restrict the priority between "levels." Furthermore, the number of descriptive objects is not limited by ordinal numbers and can be one or more. For example, in "first device," the number of "devices" can be one or more. Furthermore, the objects modified by different prefixes can be the same or different. For example, if the object being described is "device", then "first device" and "second device" can be the same device or different devices, and their types can be the same or different. Similarly, if the object being described is "information", then "first information" and "second information" can be the same information or different information, and their content can be the same or different.

[0086] In some embodiments, “including A,” “containing A,” “for indicating A,” and “carrying A” can be interpreted as directly carrying A or indirectly indicating A.

[0087] In some embodiments, the apparatus and device may be interpreted as physical or virtual, and their names are not limited to those described in the embodiments. In some cases, they may also be understood as "equipment", "device", "circuit", "network element", "node", "function", "unit", "section", "system", "network", "entity", "body", etc.

[0088] In some embodiments, the acquisition of data, information, etc., may comply with the laws and regulations of the country where the location is situated.

[0089] In some embodiments, data, information, etc., may be obtained with the user's consent.

[0090] Furthermore, each element, each row, or each column in the table of this disclosure can be implemented as an independent embodiment, and any combination of any element, any row, or any column can also be implemented as an independent embodiment.

[0091] Figure 1A is a schematic diagram of the architecture of a communication system according to an embodiment of the present disclosure.

[0092] As shown in Figure 1A, the communication system 100 includes a terminal 101 and a network device 102.

[0093] In some embodiments, terminal 101 includes, for example, at least one of the following: mobile phone, wearable device, Internet of Things device, car with communication function, smart car, tablet computer, computer with wireless transceiver function, virtual reality (VR) terminal device, augmented reality (AR) terminal device, wireless terminal device in industrial control, wireless terminal device in self-driving, wireless terminal device in remote medical surgery, wireless terminal device in smart grid, wireless terminal device in transportation safety, wireless terminal device in smart city, and wireless terminal device in smart home, but is not limited thereto.

[0094] In some embodiments, network device 102 may include at least one of access network device 102-1 and core network device 102-2.

[0095] In some embodiments, the access network device 102-1 is, for example, a node or device that connects a terminal to a wireless network. The access network device may include at least one of the following in a 5G communication system: an evolved Node B (eNB), a next-generation eNB (ng-eNB), a next-generation Node B (gNB), a node B (NB), a home node B (HNB), a home evolved node B (HeNB), a wireless backhaul device, a radio network controller (RNC), a base station controller (BSC), a base transceiver station (BTS), a base band unit (BBU), a mobile switching center, a base station in a 6G communication system, an open RAN, a cloud RAN, a base station in other communication systems, and an access node in a Wi-Fi system, but is not limited thereto.

[0096] In some embodiments, the technical solutions of this disclosure can be applied to the Open RAN architecture. In this case, the interfaces between or within access network devices involved in the embodiments of this disclosure can be transformed into internal interfaces of Open RAN. The processes and information interactions between these internal interfaces can be implemented by software or programs.

[0097] In some embodiments, the access network device 102-2 may be composed of a central unit (CU) and a distributed unit (DU). The CU may also be called a control unit. By adopting the CU-DU structure, the protocol layer of the access network device can be separated. Some of the protocol layer functions are centrally controlled by the CU, while the remaining part or all of the protocol layer functions are distributed in the DU, which is centrally controlled by the CU. However, this is not the only possibility.

[0098] In some embodiments, the core network device 102-2 may be a single device, including a first network element, a second network element, etc., or it may be multiple devices or a group of devices, each including all or part of the first network element, the second network element, etc. Network elements may be virtual or physical. The core network may include, for example, at least one of the Evolved Packet Core (EPC), 5G Core Network (5GCN), and Next Generation Core (NGC).

[0099] It is understood that the communication system described in this disclosure is for the purpose of more clearly illustrating the technical solutions of this disclosure, and does not constitute a limitation on the technical solutions proposed in this disclosure. As those skilled in the art will know, with the evolution of system architecture and the emergence of new business scenarios, the technical solutions proposed in this disclosure are also applicable to similar technical problems.

[0100] The following embodiments of this disclosure can be applied to the communication system 100 shown in FIG1A, or to some of the main bodies, but are not limited thereto. The main bodies shown in FIG1A are illustrative. The communication system may include all or some of the main bodies in FIG1A, or it may include other main bodies outside of FIG1A. The number and form of each main body are arbitrary. Each main body may be physical or virtual. The connection relationship between the main bodies is illustrative. The main bodies may not be connected or may be connected. The connection can be in any way, it can be a direct connection or an indirect connection, it can be a wired connection or a wireless connection.

[0101] The embodiments disclosed herein can be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 5G new radio (NR), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), and IEEE 802.20, Ultra-Wideband (UWB), Bluetooth (a registered trademark), Public Land Mobile Network (PLMN) networks, Device-to-Device (D2D) systems, Machine-to-Machine (M2M) systems, Internet of Things (IoT) systems, Vehicle-to-Everything (V2X) systems, systems utilizing other communication methods, and next-generation systems built upon them, etc. Furthermore, multiple systems can be combined (e.g., a combination of LTE or LTE-A with 5G).

[0102] In some embodiments, the relevant content involved in this disclosure is described below.

[0103] 1. LTM.

[0104] Network devices can provide terminals with one or more candidate configurations, where a candidate configuration can include one or more "cells (or cell groups)". The network device can subsequently control the terminal to change among the multiple "candidate configurations" (e.g., changing the working cell (or cell group) from "cell (or cell group)-1" to "cell (or cell group)-2") via L1 signaling, such as Downlink Control Information (DCI) or L2 signaling, such as Media Access Control-Control Element (MAC CE). This control signaling can be called "cell change control signaling". This process can also be called the LTM process.

[0105] LTM refers to the process where a base station receives an L1 measurement report from a terminal. Based on the received L1 measurement results, the base station can send a Cell Switch Command signaling to the terminal via MAC CE to change the serving cell. The base station pre-sends multiple LTM candidate configurations to the terminal via RRC signaling. When LTM is triggered, the sent Cell Switch Command MAC CE indicates the LTM candidate configuration corresponding to the target cell to be accessed. The terminal then applies the corresponding LTM target configuration to complete the serving cell change. The network device's ability to trigger a Cell Switch based on L1 measurement results allows for rapid channel changes and timely handover.

[0106] During LTM (Local Time Management), advance uplink and downlink synchronization for candidate cells is supported, as shown in steps S1204a and S1204b in Figure 1B. This enables RACH-less LTM cell switching during LTM. Currently, two methods are supported for obtaining the TA (Timing Advance) values ​​of LTM candidate cells in advance: timing advance acquisition and terminal-based TA measurement. This supports RACH-less LTM cell switching. Performing advance uplink and downlink synchronization for candidate cells to achieve RACH-less LTM cell switching effectively reduces data interruptions during handover.

[0107] LTM supports Subsequent LTM, meaning that the terminal does not release the LTM candidate configuration after each LTM Cell Switch. This allows the terminal to continue performing subsequent Cell Switches after mobility operations have been completed, without RRC reconfiguration or reset. Supporting Subsequent LTM effectively reduces signaling overhead.

[0108] Currently, LTM (intra-CU inter-DU LTM) and LTM within a distributed unit (intra-DU LTM) have been standardized. Further LTM enhancements are planned, including support for inter-CU LTM, condition-triggered LTM, and event-triggered L1 measurement reporting. With further advancements, LTM performance will be further improved, and its applicability will be broadened.

[0109] 2. Mobility processes based on condition triggers.

[0110] The terminal can use a network-preconfigured condition and a corresponding preconfigured cell (or cell group) as a basis. When the terminal meets the preconfigured condition (e.g., a specific measurement event), the terminal will change its serving cell (or cell group) to the preconfigured cell (or cell group). This condition-triggered mobility process includes at least one of the following:

[0111] Conditional Handover (CHO);

[0112] Conditional PSCell Addition (CPA) for primary and secondary cells (or cell groups);

[0113] Conditional PSCell Change (CPC), etc.

[0114] The terminal can also change the configuration of a specific cell (or cell group) after the "pre-configured conditions" are met, according to network instructions. For example, the terminal's PCell configuration can be changed from candidate cell (or cell group) configuration-1 to candidate cell (or cell group) configuration-2.

[0115] The "condition-triggered mobility process" also includes:

[0116] Conditional LTM (CLTM) is a type of LTM that can be used to modify both the MCG and SCG.

[0117] 3. Methods for obtaining TA during mobility (Early TA acquisition).

[0118] When configured by a network device, an uplink (UL) TA acquisition (called an early TA) process can be initiated for one or more cells that are different from the current serving cell. If the cell has the same network timing advance NTA as the current serving cell, or if NTA = 0, an early TA acquisition process is not required.

[0119] Network devices can request terminals to perform early TA acquisition of candidate cells before cell handover. The early TA acquisition process is triggered by a Physical Downlink Control Channel (PDCCH) command or implemented through terminal-based TA measurement configured by Radio Resource Control (RRC). In the former case, the base station (gNB) of the candidate cell calculates the TA value and sends it to the gNB of the serving cell. When an LTM cell handover is triggered, the serving cell sends the TA value in the LTM Cell Switching Command (MAC CE). In the latter case, the terminal performs TA measurement on the candidate cell after RRC configuration, but the exact timing of the TA measurement depends on the terminal's implementation. The terminal applies its own measured TA value and performs LTM without random access upon receiving a cell handover command. The network can also send the TA value in the LTM Cell Switching Command (MAC CE) without prior TA acquisition.

[0120] a) TA acquisition based on Random Access Channel (RACH).

[0121] For the random access procedure of LTM candidate cells used for early UL TA capture, CFRA triggered by the PDCCH command is used. The terminal sends message 1 (message1, msg1) to the cell without monitoring its response. For example, as shown in Figure 1C, the random access preamble can be allocated by the base station of the serving cell. The terminal does not need to wait for the network response in the four-step random access process and can directly send the random access preamble to the base station of the candidate cell. To support terminal power ramp, the terminal can perform a network-indicated msg1 retransmission.

[0122] b) Uplink timing management.

[0123] After receiving the TA value indicated by the network, the terminal starts a Time Alignment Timer (TAT). During the operation of this timer, the terminal considers the TA value valid and uses it for uplink transmission.

[0124] c) Configuration and maintenance of Timing Advance Group (TAG).

[0125] In the maintenance of TA in the serving cell, the terminal maintains the TA of the serving cell based on each TAG (per TAG), and each TAG corresponds to one TAT.

[0126] 4. Introduction to Dual Connectivity (DC).

[0127] 5G systems employ a DC architecture, comprising two cell (or cell group) groups:

[0128] 5G systems employ a DC architecture, comprising two cell (or cell group) groups:

[0129] The Master Cell Group (MCG) corresponds to the Master Node (MN) on the network side.

[0130] Secondary Cell Group (SCG) corresponds to secondary node (SN) on the network side.

[0131] The MCG consists of one primary cell (or cell group) (PCell) and one or more secondary cells (or cell groups) (SCell). The SCG consists of one primary secondary cell (or cell group) (PSCell) and one or more SCells. PCell and PSCell can be collectively referred to as special cells (or cell groups) (SpCell).

[0132] 5. Multi-Transmission Reception Point (Multi-TRP).

[0133] Currently, LTM supports coexistence with Multi-TRP (Multi-Downlink Control Information) in Multiple-Input Multiple-Output (MIMO). Multi-TRP-based multi-DCI Physical Downlink Shared Channel (PDSCH) and / or Physical Uplink Shared Channel (PUSCH) operation is a technique in New Radio (NR) that uses multiple independent DCIs to schedule multiple TRPs to collaboratively enhance downlink (PDSCH) and uplink (PUSCH) performance. In multi-TRP, a single cell (SpCell) can correspond to a maximum of two TAs, meaning two TAGs can be configured.

[0134] Network devices can be configured to have multiple Transmission Configuration Indicator (TRP) states for a terminal's serving cell. In this case, the network device can activate up to eight Transmission Configuration Indicator-states (TCIs) for the terminal via MAC CE. Furthermore, the network device can indicate the TCI-state used by the terminal via DCI.

[0135] In existing Raised Access Channel-less LTM (RACH-less LTM), the terminal receives a PDCCH order from the network to trigger Early Raised Access Channel (RACH). The terminal sends a preamble to the candidate cell to facilitate the candidate cell's Target Aspect (TA) measurement. When LTM is triggered, the network device includes the target cell's TA value in the Cell Switch Command MAC CE (Cell Switch Command MAC CE), and the terminal executes RACH-less LTM based on this TA value. For Conditional LTM, the terminal cannot obtain the target cell's TA value through the handover command. To implement RACH-less Conditional LTM, it is necessary to investigate how the terminal obtains the TA of the CLTM candidate cell.

[0136] In some embodiments, Release 18 (Rel-18) LTM supports coexistence with multi-DCI and multi-TRP in MIMO. In multi-TRP, a cell (SpCell) can correspond to a maximum of two TAs, meaning two TAGs can be configured. Different TCI states of a cell can correspond to different TAs, indicated by the indication information included in the TCI state configuration. Specifically, a TCI state (the TCI state of the serving cell and / or the TCI state of the candidate cell) corresponds to a timing advance packet identifier (tag-Id-ptr). This tag-Id-ptr represents the TAG associated with this TCI state. The value n0 indicates the TCI state associated with the TAG indicated by the tag identifier, and the value n1 indicates the TCI state associated with the TAG indicated by the tag2 identifier. The tag-Id-ptr refers to the TAG of the serving cell applying the TCI state.

[0137] However, currently, only the candidate configuration ID is required in the CLTM TA MAC CE. This candidate configuration ID can only indicate the candidate cell corresponding to this TA MAC CE and cannot support multi-TRP.

[0138] Furthermore, based on the number of supported tags (supportedNumberTAG), for different band combinations, the terminal currently supports a maximum of 4 serving tags simultaneously. Different serving cell PCells and SCells can correspond to the same or different tags. The terminal can currently maintain a maximum of 4 TAs. For CLTM, it currently supports configuring a maximum of 8 CLTM candidate cells simultaneously, with different candidate cells corresponding to different TATs. If the terminal maintains TATs for all candidate cells, it will need to maintain a maximum of 12 TAs simultaneously. With multi-TRP 2TA support, the number of TAs the terminal needs to maintain will be even higher, increasing the terminal's workload.

[0139] To support multiple TRPs and improve the availability of LTM, especially CLTM, this disclosure provides the following communication methods, terminals, network devices, systems, and storage media.

[0140] Figure 2 is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in Figure 2, the embodiments of the present disclosure relate to a communication method, which includes:

[0141] In step S2101, network device 102 sends a first MAC CE to terminal 101.

[0142] In some embodiments, terminal 101 receives a first MAC CE.

[0143] In some embodiments, the first MAC CE can be used to configure the TA corresponding to the CLTM.

[0144] In some embodiments, the first MAC CE can be used by terminal 101 to maintain the TA corresponding to CLTM.

[0145] In some embodiments, the name of the first MAC CE is not limited and may be referred to as CLTM MAC CE, LTM Timing Advance Command (TAC), or LTM Candidate Timing Advance Command MAC CE.

[0146] In some embodiments, the first MAC CE may include first information. This first information may be used to determine any of the following: the correspondence between the TA and the beam; the TAG to which the TA belongs.

[0147] In one example, the first information can be used to indicate the Transmission Configuration Indicator (TCI) status identifier corresponding to each TA, that is, the first information can indicate the beam applicable to each TA.

[0148] For example, when the first MAC CE is used to indicate the TA value, the candidate configuration identifier (corresponding candidate cell), and the TCI state of at least one candidate cell (i.e., indicating the beam corresponding to the candidate cell), the structure of the first MAC CE can be as shown in Figure 4A or Figure 4B. Figure 4A corresponds to one TCI state, and Figure 4B corresponds to multiple TCI states.

[0149] The candidate configuration field represents the identifier of the LTM and / or CLTM candidate cells and / or candidate configurations of the first MAC CE application, and the length of this field can be 3 bits.

[0150] The Downlink / Uplink (D / U) field indicates whether the TCI status identifier in the same octet is used for the joint TCI status, downlink TCI status, or uplink TCI status. If this field is set to 1, the TCI status identifier in the same octet is used for the joint TCI status or downlink TCI status. If this field is set to 0, the TCI status identifier in the same octet is used for the uplink TCI status.

[0151] The TCI status identifier field indicates the TCI status from the TCI status identifier (TCI StateId) in the LTM downlink or JointTCI StateToAddModList or the TCI uplink status identifier (TCI UL StateId) in the LTM uplink TCI StateToAddModList. If D / U is set to 1, a 7-bit TCI status ID, i.e., TCI StateId, is used. If D / U is set to 0, the most significant bit of the TCI status identifier is treated as a reserved bit, and the remaining 6 bits represent the TCI UL status ID. The maximum number of active TCI states is 16.

[0152] The Timing Advance Command field indicates the TA index value, which controls the timing adjustments that the MAC entity must apply when the terminal switches to a candidate cell during CLTM. The CLTM candidate cell is indicated by the latest PDCCH order before the terminal receives this MAC CE. The field is 12 bits long.

[0153] The reserved field (R) can be set to 0.

[0154] For example, when the first MAC CE is used to indicate the TA value, the candidate configuration identifier (corresponding candidate cell), and the TCI state of at least one candidate cell (i.e., indicating the beam corresponding to the candidate cell), the structure of the first MAC CE can be as shown in Figure 4C or Figure 4D. Figure 4C corresponds to one TCI state, and Figure 4D corresponds to multiple TCI states.

[0155] The contents of the candidate configuration field, the timed advance command field, and the reserved field have been described in the previous embodiments and will not be repeated here.

[0156] The TCI status identifier (ID) field indicates and / or activates the TCI status of the target cell in CLTM (i.e., the SpCell of the candidate configuration indicated by the candidate configuration ID field). The TCI status is identified by the TCI StateId in the ltm DL or JointTCI StateToAddModList. If the value of the unified DCI StateType in the ltm TCI information of the configuration indicated by the target configuration ID field is "joint", then this field is used for the joint TCI status; otherwise, this field is used for the downlink TCI status. The field length is 7 bits.

[0157] The UL TCI State ID field indicates and / or activates the uplink TCI state of the target LTM cell (i.e., the SpCell of the candidate configuration indicated by the Candidate Configuration ID field). The UL TCI state is identified by the TCI UL StateId in the specified ltm UL TCI StateToAddModList. If the unifiedTCI StateType value in the ltm TCI information of the configuration indicated by the Target Configuration ID field is separate, the octet containing this field (i.e., this field and two reserved bits in the same octet) is included. The field length is 6 bits.

[0158] The above is merely an illustrative example, and this disclosure does not limit the structure of the first MAC CE.

[0159] In one example, the first piece of information can be used to indicate the TAG to which a TA belongs. For example, TA#1 belongs to TAG#1, TA#2 belongs to TAG#2, and so on.

[0160] In one example, the first piece of information can be used to indicate the type of TA to which the TA belongs, such as TA#1 or TA#2. Here, TA#1 can be the first TAG, such as the TA in TAG#1, and TA#2 can be the second TAG, such as the TA in TAG#2.

[0161] For example, if the bit value of the first information is a first value such as "0", then the TA belongs to the first TAG, such as TAG#1.

[0162] For example, if the bit value of the first information is a second value such as "1", then the TA belongs to the second TAG, such as TAG#2. The reverse is also true.

[0163] For example, if the first MAC CE includes a TA value, a candidate configuration identifier (corresponding candidate cell), and the TAG to which the TA belongs, the structure of the first MAC CE can be as shown in Figure 4E.

[0164] The candidate configuration identifier field, the timed advance command field, and the reserved field have been described in the previous embodiments and will not be repeated here.

[0165] If two TAGs are configured for a CLTM candidate cell (i.e., the candidate configuration SpCell indicated by the candidate configuration ID field), then the TA Indicate (TI) field indicates one of the two TAGs for which LTM TAC is applied. If the CLTM candidate cell is not configured with two TAGs, then the R bit is present.

[0166] The TI field indicates different values ​​depending on the circumstances, and can be used to identify different situations.

[0167] For example, the TI field is where the first information is located. A bit value of 0 in the TI field indicates that the candidate cell corresponds to TA#1, and a bit value of 1 in the TI field indicates that the candidate cell corresponds to TA#2.

[0168] For example, the TI field is the field containing the first information. When the bit value of the TI field is 0, it indicates the tag-Id of the CLTM candidate cell. When the bit value of the TI field is 1, it indicates the tag2-Id of the CLTM candidate cell.

[0169] For example, the TI field is where the first information is located. A bit value of 1 in the TI field indicates that the candidate cell corresponds to TA#1, and a bit value of 0 in the TI field indicates that the candidate cell corresponds to TA#2.

[0170] For example, the TI field is the field containing the first information. When the bit value of the TI field is 1, it indicates the tag-Id of the CLTM candidate cell. When the bit value of the TI field is 0, it indicates the tag2-Id of the CLTM candidate cell.

[0171] For example, network device 102 may send second information to terminal 101, the second information being used to determine the first value and / or the second value.

[0172] For example, this second information can be used to determine the TAG or TA type to which the TA belongs when the value of the TI field is "0".

[0173] For example, if the second information is true, the bit value of the TI field is 1, indicating that the candidate cell corresponds to TA#1; if the bit value of the TI field is 0, it indicates that the candidate cell corresponds to TA#2. If the second information is false, the bit value of the TI field is 0, indicating that the candidate cell corresponds to TA#1; if the bit value of the TI field is 1, it indicates that the candidate cell corresponds to TA#2.

[0174] For example, if the candidate configuration ID field indicates that the candidate configuration sets the tag2 identifier to true, then a field set to 0 represents tag-2Id, and a field set to 1 represents the tag-Id of the SpCell. Otherwise, a field set to 0 represents tag-Id, and a field set to 1 indicates the tag-2Id of the SpCell.

[0175] The above is merely an illustrative example, and this disclosure does not limit the structure of the first MAC CE, the fields it includes, or the meaning of the field indications.

[0176] In some embodiments, when the network device 102 triggers the terminal 101 to perform LTM cell handover or CLTM cell handover, it sends a first MAC CE to the terminal.

[0177] In some embodiments, network device 102 sends a first MAC CE to the terminal when a TA corresponding to CLTM is required.

[0178] In some embodiments, network device 102 sends a first MAC CE to the terminal when the TA corresponding to CLTM fails or is updated.

[0179] In some embodiments, network device 102 may send a first MAC CE to terminal 101 based on a request from terminal 101.

[0180] The above is merely an illustrative example, and this disclosure does not limit the timing or event that triggers the network device 102 to send the first MAC CE to the terminal.

[0181] Step S2102: Terminal 101 maintains the TA corresponding to CLTM.

[0182] In some embodiments, terminal 101 maintains the TA corresponding to CLTM based on the first MAC CE.

[0183] In some embodiments, the terminal 101 maintains the TA corresponding to the CLTM, including but not limited to at least one of the following: storing the TA corresponding to the CLTM; starting the CLTM TAT.

[0184] In some embodiments, where the first information in the first MAC CE is used to indicate the Transmission Configuration Indicator (TCI) status identifier corresponding to each TA, the terminal 101 may maintain the TA corresponding to the CLTM in the following manner:

[0185] Method 1-1: Maintain the TA corresponding to CLTM for different candidate cells.

[0186] In one example, after receiving the first MAC CE, terminal 101 stores the TA value indicated by the first MAC CE and the TCI status corresponding to each TA, such as storing the corresponding TCI status identifier and / or uplink TCI status identifier, and starts or restarts the TAT of the candidate cell corresponding to the candidate configuration identifier indicated in the first MAC CE, i.e., CLTM TAT. In one example, terminal 101 can maintain a corresponding TA for each candidate cell.

[0187] In one example, terminal 101 can maintain the TA corresponding to CLTM at the candidate cell level. For example, it can store the TA corresponding to the candidate cell and / or start the CLTM TAT for the candidate cell.

[0188] Methods 1-2 maintain the TA corresponding to CLTM for different beams of each candidate cell.

[0189] In one example, after receiving the first MAC CE, terminal 101 stores the TA value indicated by the first MAC CE and starts or restarts the TAT (Transaction Attack) of one or more TCI states (i.e., one or more beams) corresponding to the candidate configuration identifier indicated in the first MAC CE, i.e., CLTM TAT. Here, the TAT is granular at the TCI state level, meaning one TAT corresponds to one TCI state. In one example, terminal 101 can maintain a corresponding TA for each beam of each candidate cell.

[0190] In one example, terminal 101 can maintain the TA corresponding to CLTM at the beam level. For example, it can store the TA corresponding to the beam and / or start the CLTM TAT for the beam.

[0191] In some embodiments, where the first information in the first MAC CE is used to indicate the TAG or TA type to which each TA belongs in the transmission configuration, terminal 101 may maintain the TA corresponding to CLTM in the following manner:

[0192] Method 2-1: Maintain the TA corresponding to CLTM for different candidate cells.

[0193] In one example, after receiving the first MAC CE, terminal 101 stores the TA value indicated by the first MAC CE and the corresponding first information, i.e., TI, and starts or restarts the TAT of the candidate cell corresponding to the candidate configuration identifier indicated in the first MAC CE, i.e., CLTM TAT.

[0194] In one example, a corresponding TA can be maintained for each candidate cell terminal 101.

[0195] Method 2-2: Maintain the different TAs corresponding to the CLTM of each candidate cell.

[0196] In one example, after receiving the first MAC CE, terminal 101 stores the TA value indicated by the first MAC CE and starts or restarts the CLTM TAT corresponding to TA#1 or TA#2 of the candidate configuration identifier indicated in the first MAC CE.

[0197] In one example, each candidate cell can correspond to two TATs, namely TA#1 and TA#2.

[0198] In one example, terminal 101 can maintain the TA corresponding to CLTM at the granularity of each TA of the candidate cell. For example, it stores TA#1 and TA#2 of candidate cell #1, as well as the CLMT TAT corresponding to TA#1 and the CLTM TAT corresponding to TA#2 of candidate cell #1.

[0199] The above is merely an illustrative example, and this disclosure does not limit the method by which the terminal 101 maintains the TA corresponding to CLTM.

[0200] In step S2103, terminal 101 activates and / or deactivates the corresponding TCI state.

[0201] In some embodiments, terminal 101 may activate and / or deactivate the corresponding TCI state based on the first MAC CE.

[0202] In some embodiments, terminal 101 may activate the TCI state of CLTM candidate cells based on the TCI state in the first MAC CE.

[0203] In one example, if the first TCI state is not activated before the terminal 101 receives the first MAC CE, the terminal 101 performs candidate cell TCI state activation to activate the first TCI state.

[0204] The first TCI state is the TCI state activated by the first MAC CE indication.

[0205] In one example, when terminal 101 receives the first MAC CE, it can deactivate the second TCI state, which is different from the first TCI state and belongs to any candidate cell. That is, terminal 101 can deactivate the TCI states of all other candidate cells that are already activated except for the first TCI state indicated by the first MAC CE.

[0206] In one example, when terminal 101 receives the first MAC CE, it can deactivate the third TCI state, which is different from the first TCI state, belongs to any candidate cell, and is in an active state. That is, terminal 101 can deactivate other active TCI states of candidate cells other than the first TCI state indicated by the first MAC CE.

[0207] In step S2104, terminal 101 determines to execute the first type of CLTM.

[0208] In some embodiments, the first type of CLTM does not require triggering a random access procedure, and the first type of CLTM may also be referred to as RACH-less CLTM.

[0209] In some embodiments, terminal 101 may determine to execute a first type of CLTM based on the TA corresponding to the maintained CLTM.

[0210] In some embodiments, terminal 101 evaluates CLTM execution conditions, determines the beam that meets the CLTM execution conditions (or the beam corresponding to the cell that meets the CLTM execution conditions), thereby determining the CLTM target cell, and selects a beam to access based on specific criteria or terminal implementation. This disclosure does not limit the method of beam selection.

[0211] The selected beam is the first beam.

[0212] In one example, for the aforementioned method 1-1, where the terminal maintains a TA corresponding to each candidate cell for CLTM, if the first TA is valid and the beam associated with the first TA includes the selected access first beam, then the first type of CLTM is determined to be executed. Here, the first TA is the TA corresponding to the target cell of the CLTM.

[0213] The first TA can refer to either TA#1 or TA#2 mentioned above.

[0214] For example, if the first TA is valid, such as the CLTM TAT corresponding to the CLTM target cell is being allowed, and the selected first beam is included in the beam associated with the CLTM TAT, then terminal 101 determines to perform the first type of CLTM.

[0215] In one example, for the aforementioned methods 1-2, if the terminal maintains the TA corresponding to CLTM for different beams of each candidate cell, and the second TA is valid, it is determined to execute the first type of CLTM, where the second TA is the TA corresponding to the first beam.

[0216] The second TA can refer to either TA#1 or TA#2 mentioned above.

[0217] For example, if the second TA corresponding to the first beam is valid, such as if the CLTM TAT corresponding to the first beam is running, then terminal 101 determines to execute the first type of CLTM.

[0218] In one example, regarding the aforementioned method 2-1, where the terminal maintains a TA corresponding to each candidate cell for CLTM, if the second TA is valid and the TAG indicated by the first information includes the second TA, then the first type of CLTM is determined to be executed. Here, the second TA is the TA corresponding to the first beam.

[0219] For example, if the second TA corresponding to the selected beam, the CLTM TAT corresponding to the CLTM target cell is running, and the TI associated with the CLTM TAT indicates the second TA, then terminal 101 determines that the first type of CLTM can be executed.

[0220] In one example, for the aforementioned method 2-2, if the terminal maintains different TAs for each candidate cell, and the second TA is valid, then the first type of CLTM is executed. Here, the second TA is the TA corresponding to the first beam.

[0221] For example, if the second TA corresponding to the selected beam is running, and if the CLTM TAT corresponding to the second TA of this candidate cell is running, then terminal 101 determines that the first type of CLTM can be executed.

[0222] Understandably, in other cases, terminal 101 can determine that it is performing a second type of CLTM, which is a CLTM with RACH.

[0223] In step S2105, terminal 101 sends capability information to network device 102.

[0224] In some embodiments, network device 102 receives capability information.

[0225] In some embodiments, capability information may be used to indicate a first quantity, which may be the maximum number of TAs corresponding to CLTM supported by the terminal.

[0226] In one example, terminal 101 can determine the first quantity based on its own capabilities, its own implementation, etc.

[0227] In one example, terminal 101 can determine the first quantity based on the available storage space.

[0228] In one example, terminal 101 can determine the first quantity based on the complexity of maintaining the TA corresponding to CLTM and the terminal's computing power.

[0229] This disclosure does not limit the method by which terminal 101 determines the first quantity.

[0230] In some embodiments, capability information may be used to indicate a second quantity, which may be the maximum number of TAs supported by the terminal. The TAs supported by the terminal include, but are not limited to, TAs corresponding to service TAGs and TAs corresponding to CLTMs.

[0231] In some embodiments, capability information is used to indicate a second quantity and a third quantity, wherein the second quantity is the maximum number of TAs supported by the terminal, and the third quantity is the maximum number of TAs corresponding to the quantity service TAG supported by the terminal.

[0232] In one example, terminal 101 may determine a second and / or a third quantity based on its own capabilities, implementation, etc.

[0233] In one example, terminal 101 may determine a second and / or a third quantity based on the available storage space.

[0234] In one example, terminal 101 can determine the second and / or third quantities based on the complexity of maintaining TA and the terminal's computing power.

[0235] This disclosure does not limit the manner in which terminal 101 determines the second and / or third quantities.

[0236] In one example, the sum of the first quantity and the third quantity equals the second quantity.

[0237] In one example, the way capability information indicates the second and third quantities allows for more flexible configuration of network devices compared to the way it indicates the first quantity.

[0238] For example, if the first quantity is 4, the number of TAs corresponding to the CLTM configured on the network device cannot exceed 4. If the second quantity is 10, the maximum number of TAs corresponding to the service TAG is 6. The network device 102 can allocate TAs corresponding to the service TAG and CLTM respectively based on its own policies and terminal capabilities. For example, it can configure the number of TAs corresponding to CLTM to be 6 and the number of TAs corresponding to the service TAG to be 4. Obviously, under the schemes indicating the second and third quantities of capability information, the configuration method of the network device is more flexible.

[0239] In some embodiments, capability information may be used to indicate whether the candidate cells of the CLTM support multiple TAs and / or the maximum number of candidate cells of the CLTM that support multiple TAs. It is understood that the capability information may indicate a first quantity at the granularity of frequency band, frequency band combination, or terminal, and this disclosure does not limit it in this regard.

[0240] In some embodiments, terminal 101 can send capability information to network device 102 via RRC signaling.

[0241] In some embodiments, in order to improve the reliability of the TA supported by terminal 101, terminal 101 may send capability information to network device 102.

[0242] In some embodiments, terminal 101 sends capability information to network device 102 based on instructions from network device 102.

[0243] In some embodiments, when reporting its own device capabilities, terminal 101 sends capability information to network device 102.

[0244] The above is merely an illustrative example, and this disclosure does not limit the timing or triggering event for the terminal 101 to send capability information.

[0245] In some embodiments, the names of information, etc., are not limited to the names described in the embodiments. Terms such as "information", "message", "signal", "signaling", "report", "configuration", "indication", "instruction", "command", "channel", "parameter", "domain", "field", "symbol", "symbol", "codebook", "codeword", "codepoint", "bit", "data", "program", and "chip" can be used interchangeably.

[0246] In some embodiments, terms such as “send,” “transmit,” “report,” “distribute,” “transfer,” “bidirectional transmission,” “send and / or receive” can be used interchangeably.

[0247] In some embodiments, “get,” “obtain,” “get,” “receive,” “transmit,” “bidirectional transmission,” and “send and / or receive” can be used interchangeably and can be interpreted as receiving from other entities, obtaining from protocols, obtaining from higher layers, obtaining through self-processing, or autonomous implementation, among other meanings.

[0248] In some embodiments, terms such as "certain," "preset," "default," "set," "indicated," "a certain," "any," and "first" can be used interchangeably. "Certain A," "preset A," "default A," "set A," "indicated A," "a certain A," "any A," and "first A" can be interpreted as A pre-defined in a protocol or the like, or as A obtained through setting, configuration, or instruction, or as specific A, a certain A, any A, or first A, but are not limited thereto.

[0249] In some embodiments, the communication method involved in this disclosure may include at least one of steps S2101 to S2105. For example, step S2101 may be implemented as an independent embodiment, step S2102 may be implemented as an independent embodiment, step S2101+S2102 may be implemented as an independent embodiment, step S2103 may be implemented as an independent embodiment, steps S2101 to S2103 may be implemented as independent embodiments, step S2104 may be implemented as an independent embodiment, steps S2103+S2104 may be implemented as an independent embodiment, step S2105 may be implemented as an independent embodiment, and steps S2101 to S2105 may be implemented as independent embodiments, but are not limited thereto.

[0250] In some embodiments, steps S2101 to S2105 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0251] In some embodiments, the execution order of steps S2101 to S2105 is not limited.

[0252] In the above embodiments, support for multiple transmission receiver points (TRP) is implemented, reducing the latency of performing LTM, especially CLTM.

[0253] Figure 3A is a flowchart illustrating a communication method according to an embodiment of the present disclosure. As shown in Figure 3A, the present disclosure relates to a communication method that can be executed by a terminal 101, and the method includes:

[0254] Step S3101: Obtain the first MAC CE.

[0255] In some embodiments, the first MAC CE can be used to configure the TA corresponding to the CLTM.

[0256] In some embodiments, optional implementations of step S3101 can be found in optional implementations of step S2101 in FIG2 and other related parts in the embodiments involved in FIG2, which will not be repeated here.

[0257] In some embodiments, terminal 101 receives a first MAC CE sent by network device 102, but is not limited thereto. Terminal 101 may also receive a first MAC CE sent by other entities, such as relay devices or other devices, in which case step S3101 may be omitted.

[0258] In some embodiments, terminal 101 obtains the first MAC CE as defined by the protocol, in which case step S3101 is omitted.

[0259] In some embodiments, terminal 101 obtains the first MAC CE from the upper layer(s), in which case step S3101 is omitted.

[0260] In some embodiments, the terminal 101 performs processing to obtain the first MAC CE, in which step S3101 is omitted.

[0261] In some embodiments, the terminal 101 autonomously implements the function indicated by the first MAC CE, or the above function is default or default, in which case step S3101 is omitted.

[0262] Step S3102: Maintain the TA corresponding to CLTM.

[0263] In some embodiments, optional implementations of step S3101 can be found in optional implementations of step S2102 in FIG2 and other related parts in the embodiments involved in FIG2, which will not be repeated here.

[0264] In some embodiments, steps S3101 to S3102 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0265] In some embodiments, the execution order of steps S3101 to S3102 is not limited.

[0266] In the above embodiments, support for multiple transmission receiver points (TRP) is implemented, reducing the latency of performing LTM, especially CLTM.

[0267] Figure 3B is a flowchart illustrating a communication method according to an embodiment of the present disclosure. As shown in Figure 3B, the present disclosure relates to a communication method that can be executed by a network device 102, and the method includes:

[0268] Step S3201: Send the first MAC CE.

[0269] In some embodiments, the first MAC CE can be used to configure the TA corresponding to the CLTM.

[0270] In some embodiments, network device 102 sends a first MAC CE to terminal 101.

[0271] In some embodiments, terminal 101 receives a first MAC CE.

[0272] In some embodiments, optional implementations of step S3201 can be found in optional implementations of step S2101 in FIG2 and other related parts in the embodiments involved in FIG2, which will not be repeated here.

[0273] In the above embodiments, the network device can send a first MAC CE to the terminal, and the terminal maintains the TA corresponding to CLTM, thereby supporting multiple transmit receiver points (TRP) and reducing the latency of executing LTM, especially CLTM.

[0274] The above process is further illustrated with examples below.

[0275] In this disclosure, the present invention proposes a method for acquiring and maintaining CLTM TAs, clarifying the method by which network devices indicate multiple TAs for candidate cells when supporting the coexistence of multi TRP (multi TA, also known as 2TA) and CLTM. Furthermore, it clarifies the definition method for related terminal capabilities for the maintenance of multiple CLTM TAs. Subsequently, terminals will be uniformly described using the term "User Equipment (UE)".

[0276] In this embodiment of the disclosure, the CLTM TA MAC CE contains the TCI state ID corresponding to the TA carried, which is used to indicate the TA corresponding to this TCI state or contains indication information, which is used to indicate whether this TA corresponds to TA#1 or TA#2 of this candidate cell.

[0277] The CLTM TA MAC CE carrying the TCI state ID can also be used to activate the corresponding TCI State (if it has not been activated before).

[0278] During the execution of CLTM, the UE determines whether the TAT corresponding to the selected beam (TCI state) is running; or the UE determines whether the selected beam (TCI state) corresponds to TA#1 or TA#2, and determines whether the corresponding TAT is running. If it is running, RACH-less CLTM can be executed.

[0279] In this embodiment of the disclosure, the UE reports second capability information, which is used to indicate the maximum number of TAs that the UE supports maintaining. This number of TAs includes the maximum value of the sum of the number of service TAs and the number of CLTM TAs.

[0280] In addition, the UE can also report supportedNumberTAG to indicate the maximum number of service TAGs supported by the UE. (Compared to directly reporting the maximum number of CLTM TAs that the UE supports and maintains, the network device can provide the terminal with more flexible configuration of service TAs and candidate TAs based on the above two UE capabilities).

[0281] It should be noted that the following embodiments, methods, examples, and options can all be independent embodiments or implementations, or can be combined arbitrarily, and this disclosure does not limit them.

[0282] Example 1, Method 1: The CLTM TA MAC CE contains the TCI state ID corresponding to the carried TA, which is used to indicate the TA corresponding to this TCI state.

[0283] In addition, the CLTM TA MAC CE carrying the TCI state ID can also be used to activate the corresponding TCI State (if it has not been activated before).

[0284] Example 1-1: The structure of a MAC CE (e.g., referred to as LTM TAC, LTM Candidate TAC, LTM Candidate Timing Advance Command MAC CE) sent by a network device for a CLTM TA can be shown, for example, in Figures 4A, 4B, 4C, and 4D.

[0285] A CLTM TA's MAC CE indicates the associated TA value, its corresponding candidate configuration identifier (i.e., the candidate cell), and the TCI State (i.e., the beam corresponding to the candidate cell) of one or more candidate cells.

[0286] Option 1, Figure 4A indicates one TCI state, and Figure 4B indicates multiple TCI states.

[0287] The meanings of each field in MAC CE are as follows:

[0288] The candidate configuration field represents the identifier of the LTM and / or CLTM candidate cells and / or candidate configurations of the first MAC CE application, and the length of this field can be 3 bits.

[0289] The Downlink / Uplink (D / U) field indicates whether the TCI status identifier in the same octet is used for the joint TCI status, downlink TCI status, or uplink TCI status. If this field is set to 1, the TCI status identifier in the same octet is used for the joint TCI status or downlink TCI status. If this field is set to 0, the TCI status identifier in the same octet is used for the uplink TCI status.

[0290] The TCI status identifier field indicates the TCI status from the TCI status identifier (TCI StateId) in the LTM downlink or JointTCI StateToAddModList or the TCI uplink status identifier (TCI UL StateId) in the LTM uplink TCI StateToAddModList. If D / U is set to 1, a 7-bit TCI status ID, i.e., TCI StateId, is used. If D / U is set to 0, the most significant bit of the TCI status identifier is treated as a reserved bit, and the remaining 6 bits represent the TCI UL status ID. The maximum number of active TCI states is 16.

[0291] The Timing Advance Command field indicates the TA index value, which controls the timing adjustments that the MAC entity must apply when the terminal switches to a candidate cell during CLTM. The CLTM candidate cell is indicated by the latest PDCCH order before the terminal receives this MAC CE. The field is 12 bits long.

[0292] The reserved field (R) can be set to 0.

[0293] Option 2, Figure 4C indicates one TCI state, and Figure 4D indicates multiple TCI states.

[0294] The meanings of each field in MAC CE are as follows:

[0295] The candidate configuration identifier field, the timed advance command field, and the reserved field are the same as above.

[0296] The TCI status identifier (ID) field indicates and / or activates the TCI status of the target cell in CLTM (i.e., the SpCell of the candidate configuration indicated by the candidate configuration ID field). The TCI status is identified by the TCI StateId in the ltm DL or JointTCI StateToAddModList. If the value of the unified DCI StateType in the ltm TCI information of the configuration indicated by the target configuration ID field is "joint", then this field is used for the joint TCI status; otherwise, this field is used for the downlink TCI status. The field length is 7 bits.

[0297] The UL TCI State ID field indicates and / or activates the uplink TCI state of the target LTM cell (i.e., the SpCell of the candidate configuration indicated by the Candidate Configuration ID field). The UL TCI state is identified by the TCI UL StateId in the specified ltm UL TCI StateToAddModList. If the unifiedTCI StateType value in the ltm TCI information of the configuration indicated by the Target Configuration ID field is separate, the octet containing this field (i.e., this field and two reserved bits in the same octet) is included. The field length is 6 bits.

[0298] Example 1-2: After the UE receives the MAC CE that sent the CLTM TA in Example 1-1, how does it maintain the TA of the CLTM Candidate?

[0299] Option 1: The UE maintains a TA for each candidate cell separately.

[0300] The UE receives the MAC CE of CLTM TA sent by the network side, stores the TA value indicated in this MAC CE and one or more corresponding beam / TCI states (e.g., stores the corresponding TCI state ID and / or UL TCI state ID), and starts or restarts the TA timer (CLTM TAT) corresponding to the candidate cell indicated in this MAC CE.

[0301] Option 2: The UE maintains TA separately for different beams of different candidate cells.

[0302] The UE receives the MAC CE of the CLTM TA sent by the network side, stores the TA value indicated in this MAC CE, and starts or restarts the TA timer (CLTM TAT) corresponding to one or more beams (TCI State) indicated in this MAC CE. This TAT ​​is per TCI state.

[0303] Examples 1-3: The UE can activate the CLTM candidate cell TCI state based on the TCI state indicated in CLTM TA MAC CE.

[0304] Example 1: When receiving a CLTM TA MAC CE carrying the TCI state, if the UE has not previously activated this TCI state, the UE performs Candidate Cell TCI States Activation to activate this TCI state.

[0305] Example 2: Upon receiving a CLTM TA MAC CE carrying the TCI state, the UE deactivates the TCI states of all other activated candidate cells except those indicated in this MAC CE.

[0306] Example 3: Upon receiving a CLTM TA MAC CE carrying the TCI state, the UE deactivates other activated TCI states of the candidate cell indicated in this MAC CE, besides the TCI state indicated in this MAC CE.

[0307] Examples 1-4: During the execution of CLTM, the UE determines whether RACH-less CLTM can be executed based on the TA of the maintained CLTM candidate cells.

[0308] The UE evaluates the CLTM execution conditions, determines the beams that meet the conditions (or the beams corresponding to cells that meet the conditions), determines the CLTM target cell, and then selects a beam to access based on specific criteria or terminal implementation (the method of beam selection is not constrained in this invention).

[0309] For example (corresponding to Option 1 in Embodiments 1-2), if the CLTM TAT corresponding to the CLTM target cell is running and the selected beam is included in the beams associated with this CLTM TAT, then RACH-less CLTM can be performed.

[0310] For example (corresponding to Option 2 in Embodiments 1-2), if the CLTM TAT corresponding to this beam (TCI state ID) is running, RACH-less CLTM can be executed.

[0311] Method 2: The CLTM TA MAC CE includes indication information (e.g., the TI field) corresponding to the carried TA, which is used to indicate whether the TA information corresponds to the tag-id or tag2-id.

[0312] When the UE receives this CLTM TA MAC CE, it stores the corresponding TA and the corresponding TA indication information, and initiates the relevant CLTM TAT. When the UE executes CLTM, the UE determines whether the TA corresponding to this beam is the TA of tag-id or tag2-id based on the tag-Id-ptr indicated in the TCI state corresponding to the selected beam, and then evaluates whether the relevant TA is valid, thereby determining whether to execute RACH-less CLTM.

[0313] The structure of the MAC CE for sending CLTM TA in Method 2 can be as shown in Figure 4E.

[0314] The candidate configuration identifier field, the timed advance command field, and the reserved field are the same as above.

[0315] If two TAGs are configured for a CLTM candidate cell (i.e., the candidate configuration SpCell indicated by the candidate configuration ID field), then the TA Indicate (TI) field indicates one of the two TAGs for which LTM TAC is applied. If the CLTM candidate cell is not configured with two TAGs, then the R bit is present.

[0316] In different situations, different values ​​of the indicator information can identify different situations.

[0317] Example 1: Indication information 0 indicates TA#1 corresponding to the candidate cell, and indication information 1 indicates TA#2 corresponding to the candidate cell.

[0318] Setting the TI field to 0 indicates the tag-Id of the CLTM candidate cell, and setting it to 1 indicates the tag2-Id.

[0319] Example 2: Indication information 0 indicates that the candidate cell corresponds to TA#2, and indication information 1 indicates that the candidate cell corresponds to TA#1.

[0320] The TI field is set to 0 to indicate the tag2-Id of the CLTM candidate cell, and set to 1 to indicate the tag-Id.

[0321] Example 3: Based on the second indication information in the candidate cell configuration of the RRC layer, determine the meaning of different fields in the indication information in this MAC CE. If the second indication information is true, then indication information 0 indicates TA#2 corresponding to the candidate cell, and indication information 1 indicates TA#1 corresponding to the candidate cell; otherwise, indication information 0 indicates TA#1 corresponding to the candidate cell, and indication information 1 indicates TA#2 corresponding to the candidate cell.

[0322] If the candidate configuration ID field indicates that the candidate configuration sets tag2-Id to true, then a field set to 0 represents tag2-Id, and a field set to 1 represents the tag-Id of the SpCell. Otherwise, a field set to 0 represents tag-Id, and a field set to 1 indicates the tag2-Id of the SpCell.

[0323] Example 2-2: After the UE receives the MAC CE that sent the CLTM TA in Example 2-1, how does it maintain the TA of the CLTM Candidate?

[0324] Option 1: The UE maintains a TA for each candidate cell separately.

[0325] The UE receives the MAC CE of the CLTM TA sent by the network side, stores the TA value indicated in this MAC CE and the corresponding indication information (TI), and starts or restarts the TA timer (CLTM TAT) corresponding to the candidate cell indicated in this MAC CE.

[0326] Option 2: The UE maintains TA for TA#1 and TA#2 of different candidate cells respectively.

[0327] The UE receives the MAC CE of the CLTM TA sent by the network side, stores the TA value indicated in this MAC CE, and starts or restarts the TA timer (CLTM TAT) corresponding to TA#1 or TA#2 of the Candidate Config ID indicated in this MAC CE. One candidate cell can correspond to 2 TATs, and TA#1 and TA#2 each correspond to 2 TATs.

[0328] Examples 1-3: During the execution of CLTM, the UE determines whether RACH-less CLTM can be executed based on the TA of the maintained CLTM candidate cells.

[0329] The UE evaluates the CLTM execution conditions, determines the beams that meet the conditions (or the beams corresponding to cells that meet the conditions), determines the CLTM target cell, and then selects a beam to access based on specific criteria or terminal implementation (the method of beam selection is not constrained in this invention).

[0330] When the UE performs CLTM, the UE determines whether the TA corresponding to this beam is the TA of tag-id (TA#1) or the TA of tag2-id (TA#2) based on the tag-Id-ptr indicated in the TCI state corresponding to the selected beam.

[0331] For example, (corresponding to Option 1 in embodiment 2-2), if the selected beam corresponds to TA#1, if the CLTM TAT corresponding to the CLTM target cell is running, and the TI associated with this CLTM TAT indicates TA#1, then RACH-less CLTM can be executed.

[0332] For example (corresponding to Option 2-2 in embodiment 2), if the selected beam corresponds to TA#1, and if the CLTM TAT corresponding to TA#1 of this candidate cell is running, then RACH-less CLTM can be executed.

[0333] In some embodiments, the above process may correspond to steps S2101 to S2104 in FIG2, and the specific process will not be described in detail here.

[0334] Example 1 of Example 3: The UE reports first capability information, which is used to indicate the maximum number of CLTM TAs that the UE supports maintaining.

[0335] This UE capability information can be any one or more of the following: per band, per band combination, and per UE.

[0336] Example 2: The UE reports second capability information, which is used to indicate the maximum number of TAs that the UE supports maintaining. This number of TAs includes the number of service TAs and the number of CLTM TAs.

[0337] This UE capability information can be any one or more of per Band, per Band Combination, and per UE.

[0338] In addition, the UE can also report third capability information, such as supportedNumberTAG, to indicate the maximum number of service TAGs supported by the UE (compared to Example 1, the network device can configure service TAGs and candidate TAGs for the UE more flexibly based on the above two UE capabilities).

[0339] Example 3: The UE reports fourth capability information, which is used to indicate whether the candidate cells of CLTM support multiple TAs (2TAs) and / or the maximum number of candidate cells of CLTM that support 2TAs.

[0340] In some embodiments, the above process may correspond to steps S2105 to S2108 in FIG2, and the specific process will not be described in detail here.

[0341] This disclosure also proposes an apparatus (also referred to as a communication device, etc.) for implementing any of the above methods. For example, an apparatus is proposed that includes units or modules for implementing the steps performed by the terminal in any of the above methods. Furthermore, another apparatus is proposed that includes units or modules for implementing the steps performed by a network device (e.g., an access network device, a core network functional node, a core network device, etc.) in any of the above methods.

[0342] It should be understood that the division of units or modules in the above device is only a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, the units or modules in the device can be implemented by a processor calling software: for example, the device includes a processor connected to a memory containing instructions. The processor calls the instructions stored in the memory to implement any of the above methods or to implement the functions of the units or modules in the above device. The processor can be, for example, a general-purpose processor, such as a Central Processing Unit (CPU) or a microprocessor, and the memory can be internal or external to the device. Alternatively, the units or modules in the device can be implemented in the form of hardware circuits. The functionality of some or all of the units or modules can be achieved through the design of these hardware circuits, which can be understood as one or more processors. For example, in one implementation, the hardware circuit is an application-specific integrated circuit (ASIC). The functionality of some or all of the units or modules is achieved through the design of the logical relationships between the components within the circuit. In another implementation, the hardware circuit can be implemented using a programmable logic device (PLD). Taking a field-programmable gate array (FPGA) as an example, it can include a large number of logic gates. The connection relationships between the logic gates are configured through configuration files, thereby achieving the functionality of some or all of the units or modules. All units or modules of the above device can be implemented entirely through processor-called software, entirely through hardware circuits, or partially through processor-called software with the remaining parts implemented through hardware circuits.

[0343] In this embodiment, the processor is a circuit with signal processing capabilities. In one implementation, the processor can be a circuit with instruction read and execute capabilities, such as a Central Processing Unit (CPU), a microprocessor, a graphics processing unit (GPU) (which can be understood as a microprocessor), or a digital signal processor (DSP). In another implementation, the processor can implement certain functions through the logical relationships of hardware circuits. The logical relationships of the aforementioned hardware circuits are fixed or reconfigurable. For example, the processor is a hardware circuit implemented using an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as an FPGA. In a reconfigurable hardware circuit, the process of the processor loading a configuration document and configuring the hardware circuit can be understood as the process of the processor loading instructions to implement the functions of some or all of the above units or modules. Furthermore, it can also be a hardware circuit designed for artificial intelligence, which can be understood as an ASIC, such as a Neural Network Processing Unit (NPU), a Tensor Processing Unit (TPU), or a Deep Learning Processing Unit (DPU).

[0344] Figure 5A is a schematic diagram of the structure of a terminal according to an embodiment of this disclosure. The terminal 5100 is used to execute any of the above methods. In some embodiments, as shown in Figure 5A, the terminal 5100 may include at least one of a transceiver module 5101 and a processing module 5102.

[0345] In some embodiments, the transceiver module 5101 is used to receive a first media access control unit (MAC CE) sent by a network device, wherein the first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by condition layer 1 or layer 2.

[0346] In some embodiments, the processing module 5102 is used to maintain the TA corresponding to the CLTM based on the first MAC CE.

[0347] Optionally, the transceiver module 5101 is used to perform at least one of the communication steps such as receiving and / or sending performed by the terminal 5100 in any of the above methods (e.g., steps S2101, S2105, S2106, S2107, S2108, but not limited thereto), which will not be elaborated here.

[0348] Optionally, the processing module 5102 is used to execute at least one of the other steps (such as step S2102, step S2103, step S2104, but not limited thereto) executed by the terminal 5100 in any of the above methods, which will not be elaborated here.

[0349] Figure 5B is a schematic diagram of the structure of a network device according to an embodiment of this disclosure. The network device 5200 is used to perform any of the above methods. In some embodiments, as shown in Figure 5B, the network device 5200 may include a transceiver module 5201.

[0350] In some embodiments, the transceiver module 5201 is used to send a first media access control unit (MAC CE) to the terminal, wherein the first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by condition layer 1 and layer 2; wherein the first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

[0351] Optionally, the transceiver module 5201 is used to perform at least one of the communication steps such as receiving and / or sending performed by the network device 5200 in any of the above methods (e.g., steps S2101, S2105, S2106, S2107, S2108, but not limited thereto), which will not be elaborated here.

[0352] In some embodiments, the transceiver module may include a transmitting module and / or a receiving module, which may be separate or integrated. Optionally, the transceiver module may be interchangeable with a transceiver.

[0353] In some embodiments, the processing module may be a single module or may include multiple sub-modules. Optionally, the multiple sub-modules may each perform all or part of the steps required by the processing module. Optionally, the processing module may be interchangeable with a processor, and the transceiver module may be interchangeable with a transceiver.

[0354] Figure 6A is a schematic diagram of the structure of the communication device 6100 proposed in an embodiment of this disclosure. The communication device 6100 can be a network device (e.g., access network device, core network device, etc.), a terminal (e.g., user equipment, etc.), a chip, chip system, or processor that supports the network device in implementing any of the above methods, or a chip, chip system, or processor that supports the terminal in implementing any of the above methods. The communication device 6100 can be used to implement the methods described in the above method embodiments; for details, please refer to the descriptions in the above method embodiments.

[0355] As shown in Figure 6A, the communication device 6100 is used to execute any of the above methods. In some embodiments, the communication device 6100 includes one or more processors 6101. The processor 6101 may be a general-purpose processor or a special-purpose processor, such as a baseband processor or a central processing unit. The baseband processor may be used to process communication protocols and communication data, and the central processing unit may be used to control communication devices (e.g., base stations, baseband chips, terminal devices, terminal device chips, DUs or CUs, etc.), execute programs, and process program data. Optionally, the communication device 6100 is used to execute any of the above methods. Optionally, one or more processors 6101 are used to invoke instructions to cause the communication device 6100 to execute any of the above methods.

[0356] In some embodiments, the communication device 6100 further includes one or more transceivers 6102. When the communication device 6100 includes one or more transceivers 6102, the transceiver 6102 performs at least one of the communication steps such as sending and / or receiving in the above method (e.g., steps S2101, S2105, S2106, S2107, S2108, but not limited thereto), and the processor 6101 performs at least one of other steps (e.g., steps S2102, S2103, S2104, but not limited thereto). In optional embodiments, the transceiver may include a receiver and / or a transmitter, which may be separate or integrated. Optionally, the terms transceiver, transceiver unit, transceiver, transceiver circuit, interface circuit, interface, etc., can be used interchangeably; the terms transmitter, transmitting unit, transmitter, transmitting circuit, etc., can be used interchangeably; the terms receiver, receiving unit, receiver, receiving circuit, etc., can be used interchangeably.

[0357] In some embodiments, the communication device 6100 further includes one or more memories 6103 for storing data and / or instructions. Optionally, one or more processors 6101 are used to invoke instructions stored in the memory 6103 to cause the communication device 6100 to perform any of the above methods. Optionally, all or part of the memory 6103 may also be located outside the communication device 6100. In an optional embodiment, the communication device 6100 may include one or more interface circuits 6104. Optionally, the interface circuit 6104 is connected to the memory 6103 and can be used to receive data and / or instructions from the memory 6103 or other devices, and can be used to send data and / or instructions to the memory 6103 or other devices. For example, the interface circuit 6104 can read data and / or instructions stored in the memory 6103 and send the data and / or instructions to the processor 6101.

[0358] The communication device 6100 described in the above embodiments may be a network device or a terminal, but the scope of the communication device 6100 described in this disclosure is not limited thereto, and the structure of the communication device 6100 may not be limited by FIG. 6A. The communication device may be a standalone device or a part of a larger device. For example, the communication device may be: (1) a standalone integrated circuit IC, or chip, or chip system or subsystem; (2) a collection of one or more ICs, optionally, the IC collection may also include storage components for storing data, programs and / or instructions; (3) an ASIC, such as a modem; (4) a module that can be embedded in other devices; (5) a receiver, terminal device, smart terminal device, cellular phone, wireless device, handheld device, mobile unit, vehicle device, network device, cloud device, artificial intelligence device, etc.; (6) others, etc.

[0359] Figure 6B is a schematic diagram of the structure of chip 6200 according to an embodiment of this disclosure. For cases where the communication device 6100 can be a chip or a chip system, please refer to the schematic diagram of chip 6200 shown in Figure 6B, but it is not limited thereto.

[0360] Chip 6200 includes one or more processors 6201. Chip 6200 is used to perform any of the methods described above.

[0361] In some embodiments, chip 6200 further includes one or more interface circuits 6202. Optionally, terms such as interface circuit, interface, and transceiver pin can be used interchangeably. In some embodiments, chip 6200 further includes one or more memories 6203 for storing data and / or instructions. Optionally, all or part of the memories 6203 may be located outside of chip 6200. Optionally, interface circuit 6202 is connected to memory 6203, and interface circuit 6202 can be used to receive data and / or instructions from memory 6203 or other devices, and interface circuit 6202 can be used to send data and / or instructions to memory 6203 or other devices. For example, interface circuit 6202 can read data and / or instructions stored in memory 6203 and send the data and / or instructions to processor 6201.

[0362] In some embodiments, the interface circuit 6202 performs at least one of the communication steps such as sending and / or receiving in the above-described method (e.g., steps S2101, S2105, S2106, S2107, and S2108, but not limited thereto). The interface circuit 6202 performing the communication steps such as sending and / or receiving in the above-described method refers, for example, to the interface circuit 6202 performing data and / or instruction interaction between the processor 6201, the chip 6200, the memory 6203, or the transceiver device. In some embodiments, the processor 6201 performs at least one of other steps (e.g., steps S2102, S2103, and S2104, but not limited thereto).

[0363] The modules and / or devices described in the various embodiments, such as virtual devices, physical devices, and chips, can be combined or separated arbitrarily as needed. Optionally, some or all steps can also be performed collaboratively by multiple modules and / or devices, which is not limited here.

[0364] This disclosure also proposes a storage medium storing instructions that, when executed on a communication device, cause the communication device to perform any of the above methods. Optionally, the storage medium is an electronic storage medium. Optionally, the storage medium is a computer-readable storage medium, but not limited thereto; it may also be a storage medium readable by other devices. Optionally, the storage medium may be a non-transitory storage medium, but not limited thereto; it may also be a temporary storage medium.

[0365] This disclosure also proposes a program product, including a program and / or instructions, which, when executed by a communication device, cause the communication device to perform any of the above methods. Optionally, the program product is a computer program product. Optionally, the program product is stored on the storage medium.

[0366] This disclosure also proposes a computer program that, when run on a computer, causes the computer to perform any of the above methods.

[0367] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0368] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A communication method, characterized in that, The method is executed by a terminal, and the method includes: The network device receives a first media access control unit (MAC CE) sent by the network device. The first MAC CE is used to configure the timing advance (TA) corresponding to the mobility CLTM triggered by condition layer 1 and layer 2. Based on the first MAC CE, maintain the TA corresponding to CLTM.

2. The method according to claim 1, characterized in that, The first MAC CE includes first information, which indicates at least one of the following: Each TA corresponds to a Transmission Configuration Indicator (TCI) status identifier; The scheduled advance grouping TAG to which TA belongs.

3. The method according to claim 2, characterized in that, When the bit value of the first information is a first value, the TA belongs to the first TAG; and / or If the bit value of the first information is the second value, then the TA belongs to the second TAG.

4. The method according to claim 3, characterized in that, The method further includes: The network device receives second information, which is used to determine the first value and / or the second value.

5. The method according to any one of claims 1-4, characterized in that, The TA corresponding to the maintenance CLTM includes at least one of the following: Maintain the TA corresponding to CLTM for each candidate cell; Maintain the corresponding TA for CLTM for each candidate cell's different beams; Maintain the different TAs corresponding to CLTM in each candidate cell.

6. The method according to any one of claims 1-5, characterized in that, The method further includes at least one of the following: Based on the first MAC CE, activate the first TCI state; Based on the first MAC CE, the second TCI state is deactivated. The second TCI state is different from the first TCI state and belongs to any candidate cell. Wherein, the first TCI state is the TCI state activated by the first MAC CE indication.

7. The method according to any one of claims 1-6, characterized in that, The method further includes: Based on the TA corresponding to the maintained CLTM, the execution of the first type of CLTM is determined, and the first type of CLTM does not require triggering a random access procedure.

8. The method according to claim 7, characterized in that, The determination of executing the first type of CLTM based on the TA corresponding to the maintained CLTM includes any of the following: When maintaining a TA corresponding to CLTM for each candidate cell, if the first TA is valid and the beam associated with the first TA includes the first beam, it is determined that the first type of CLTM will be executed, where the first TA is the TA corresponding to the target cell of CLTM. If a TA is maintained for each candidate cell in the case of maintaining a CLTM corresponding to it, and if the second TA is valid and the TAG indicated by the first information includes the second TA, then the first type of CLTM is determined to be executed. When maintaining the TA corresponding to CLTM for different beams of each candidate cell, if the second TA is valid, it is determined that the first type of CLTM will be executed, and the second TA is the TA corresponding to the first beam. If the second TA is valid, and different TAs are maintained for CLTM in each candidate cell, then the first type of CLTM is executed. Wherein, the second TA is the TA corresponding to the first beam, and the first beam is the beam that satisfies the CLTM execution conditions.

9. The method according to any one of claims 1-8, characterized in that, The method further includes: Send capability information to the network device, the capability information indicating at least one of the following: The first quantity is the maximum number of TAs corresponding to the CLTM that the terminal supports maintaining; The second quantity is the maximum number of TAs supported by the terminal; The third quantity is the maximum number of TAs corresponding to the service TAGs supported by the terminal; Does the candidate cell of the CLTM support multiple TAs? The maximum number of candidate cells for CLTM that supports multiple TAs.

10. A communication method, characterized in that, The method is performed by a network device, and the method includes: Send a first Media Access Control Unit (MAC CE) to the terminal. The first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by Conditional Layer 1 and Layer 2. The first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

11. The method according to claim 10, characterized in that, The first MAC CE includes first information, which indicates at least one of the following: Each TA corresponds to a Transmission Configuration Indicator (TCI) status identifier; The scheduled advance grouping TAG to which TA belongs.

12. The method according to claim 11, characterized in that, When the bit value of the first information is a first value, the TA belongs to the first TAG; and / or If the bit value of the first information is the second value, then the TA belongs to the second TAG.

13. The method according to claim 12, characterized in that, The method further includes: The network device receives second information, which is used to determine the first value and / or the second value.

14. The method according to any one of claims 10-13, characterized in that, The first MAC CE is used for at least one of the following: Activate the first TCI state; Deactivate the second TCI state, which is different from the first TCI state and belongs to any candidate cell. Wherein, the first TCI state is the TCI state activated by the first MAC CE indication.

15. The method according to any one of claims 10-14, characterized in that, The method further includes: Receive capability information sent by the terminal, the capability information being used to indicate at least one of the following: The first quantity is the maximum number of TAs corresponding to the CLTM supported by the terminal; The second quantity is the maximum number of TAs supported by the terminal; The third quantity is the maximum number of TAs corresponding to the service TAGs supported by the terminal; Does the candidate cell of the CLTM support multiple TAs? The maximum number of candidate cells for CLTM that supports multiple TAs.

16. A terminal, characterized in that, include: The transceiver module is configured to receive a first media access control unit (MAC CE) sent by a network device. The first MAC CE is used to configure the timing advance (TA) corresponding to the mobility CLTM triggered by conditional layer 1 or layer 2. The processing module is configured to maintain the TA corresponding to the CLTM based on the first MAC CE.

17. A network device, characterized in that, include: The transceiver module is configured to send a first media access control unit (MAC CE) to the terminal. The first MAC CE is used to configure the timing advance amount (TA) corresponding to the mobility CLTM triggered by condition layer 1 and layer 2. The first MAC CE is used by the terminal to maintain the TA corresponding to the CLTM.

18. A terminal, characterized in that, include: One or more processors; The processor is used to execute the method according to any one of claims 1-9.

19. A network device, characterized in that, include: One or more processors; The processor is used to execute the communication method according to any one of claims 10-15.

20. A communication system, characterized in that, include: A terminal configured to implement the communication method according to any one of claims 1-9; A network device configured to implement the communication method according to any one of claims 10-15.

21. A storage medium storing instructions, characterized in that, When the instruction is executed on the communication device, it causes the communication device to perform the communication method as described in any one of claims 1-9 or 10-15.

22. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program is used to implement the communication method according to any one of claims 1-12 or 10-15.

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