Cell handover method and apparatus, transmission failure processing method and apparatus, and terminal

Abstract

The present application relates to the technical field of communications, and discloses a cell handover method and apparatus, a transmission failure processing method and apparatus, and a terminal. The cell handover method in embodiments of the present application comprises: when a first condition is satisfied, a terminal determines that a RACH-less cell handover is in progress. The first condition comprises at least one of the following: at a first moment when a trigger condition LTM is executed, a TA timer corresponding to a target cell is running or has not expired, or there is an available configured grant resource; when the trigger condition LTM is executed, the terminal is configured with a configured grant resource, or there is a configured grant resource associated with a target reference signal or beam selected by the terminal, or the terminal is configured with a configured grant resource related to RACH-less operation; within a first time length after the trigger condition LTM is executed, there is an available configured grant resource; and on the first available configured grant resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not expired.

Description

Cell handover methods, transmission failure handling methods, devices and terminals

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510385237.4, filed in China on March 28, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of communication technology, specifically relating to a cell handover method, a transmission failure handling method, an apparatus, and a terminal. Background Technology

[0004] To reduce handover latency, current technologies introduce Layer 1 or Layer 2 Triggered Mobility (LTM), where the Distributed Unit (DU) instructs the terminal to hand over to a suitable candidate cell based on the Layer 1 measurement results reported by the terminal using Layer 1 or Layer 2 signaling.

[0005] In related technologies, LTM-based handover includes two cell handover methods: Random Access Channel-based (RACH-based) and Random Access Channel-less (RACH-less). However, these technologies do not provide instructions on how the terminal should select the cell handover method. Summary of the Invention

[0006] This application provides a cell handover method, a transmission failure handling method, an apparatus, and a terminal, which can solve the problem that there is no relevant solution in the related art to instruct the terminal on how to select the cell handover mode.

[0007] Firstly, a cell handover method is provided, the method comprising:

[0008] If a first condition is met, the terminal considers that a cell handover without a random access channel (RACH-less) is in progress; wherein the first condition includes at least one of the following:

[0009] At the first moment of the execution of Mobility LTM triggered by Layer 1 or Layer 2, the Time Advance (TA) timer corresponding to the target cell is running or has not timed out;

[0010] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources;

[0011] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0012] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less;

[0013] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0014] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources;

[0015] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0016] Secondly, a method for handling transmission failures is provided, the method further comprising:

[0017] If the second condition is met, the terminal performs the first action; the second condition includes: the uplink transmission performed by the terminal on the target configuration authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out.

[0018] The first action includes at least one of the following:

[0019] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0020] Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

[0021] Thirdly, a cell handover device is provided, the device comprising:

[0022] A first processing module is configured to consider a cell handover without a random access channel (RACH-less) to be in progress if a first condition is met; wherein the first condition includes at least one of the following:

[0023] At the first moment of LTM triggering, the timing advance timer (TA) for the target cell is either running or has not timed out.

[0024] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources;

[0025] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0026] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less;

[0027] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0028] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources;

[0029] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0030] Fourthly, a transmission failure handling apparatus is provided, the apparatus comprising:

[0031] The sixth processing module is used to execute the first action when the second condition is met; the second condition includes: the uplink transmission performed by the terminal on the target configuration authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out;

[0032] The first action includes at least one of the following:

[0033] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0034] Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

[0035] Fifthly, a cell handover apparatus or transmission failure handling apparatus is provided, the apparatus being configured to perform the steps of the method described in the first aspect, or to implement the steps of the method described in the second aspect.

[0036] In a sixth aspect, a terminal is provided, the terminal including a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the method as described in the first aspect, or implementing the steps of the method as described in the second aspect.

[0037] In a seventh aspect, a terminal is provided, including a processor and a communication interface, wherein the processor is configured to consider a cell handover without a random access channel (RACH-less) to be in progress when a first condition is met; wherein the first condition includes at least one of the following:

[0038] At the first moment of the execution of Mobility LTM triggered by Layer 1 or Layer 2, the Time Advance (TA) timer corresponding to the target cell is running or has not timed out;

[0039] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources;

[0040] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0041] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less;

[0042] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0043] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources;

[0044] On the first available configuration grant resource after the LTM trigger condition is executed, the TA timer corresponding to the target cell is running or has not timed out. Alternatively, the processor is configured to have the terminal perform the first action if a second condition is met; the second condition includes: the uplink transmission performed by the terminal on the target configuration grant resource fails, or the retransmission timer of the target grant resource times out, or the timer of the target grant resource times out.

[0045] The first action includes at least one of the following:

[0046] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0047] Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

[0048] Eighthly, a readable storage medium is provided, on which a program or instructions are stored, which, when executed by a processor, implement the steps of the method described in the first aspect, or implement the steps of the method described in the second aspect.

[0049] In a ninth aspect, a chip is provided, the chip including a processor and a communication interface coupled to the processor, the processor being configured to run a program or instructions to implement the steps of the method as described in the first aspect, or to implement the steps of the method as described in the second aspect.

[0050] In a tenth aspect, a computer program / program product is provided, the computer program / program product being stored in a storage medium, the computer program / program product being executed by at least one processor to implement the steps of the method as described in the first aspect, or to implement the steps of the method as described in the second aspect.

[0051] In this embodiment of the application, when the terminal triggers the execution of conditional LTM, it determines whether a RACH-less cell handover is in progress based on a first condition. This allows the terminal to correctly determine whether RACH-less is used during the execution of conditional LTM, enabling the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process. It also avoids the problem that the terminal still uses RACH-less when it cannot use it, thus causing the handover failure. Attached Figure Description

[0052] Figure 1 shows a block diagram of a wireless communication system that can be applied to an embodiment of this application;

[0053] Figure 2 is a schematic diagram of the steps of the cell handover method provided in the embodiment of this application;

[0054] Figure 3 is a schematic diagram of the steps of the transmission failure handling method provided in the embodiment of this application;

[0055] Figure 4 shows a schematic diagram of the cell handover device provided in an embodiment of this application;

[0056] Figure 5 shows a schematic diagram of the transmission failure handling device provided in an embodiment of this application;

[0057] Figure 6 shows a schematic diagram of the structure of the communication device provided in an embodiment of this application;

[0058] Figure 7 shows a schematic diagram of the structure of the terminal provided in the embodiment of this application. Detailed Implementation

[0059] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0060] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, not limited in number; for example, the first object can be one or more. Furthermore, "or" in this application indicates at least one of the connected objects. For example, the scope of protection for "A or B" covers at least three scenarios: Scenario 1: including A but not B; Scenario 2: including B but not A; Scenario 3: including both A and B. In addition, the terms "A and / or B," "at least one of A and B," and "at least one of A or B" also cover at least the above three scenarios. The character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0061] The term "instruction" in this application can be either a direct instruction (or explicit instruction) or an indirect instruction (or implicit instruction). A direct instruction can be understood as the sender explicitly informing the receiver of specific information, the required operation, or the requested result in the instruction sent. An indirect instruction can be understood as the receiver determining the corresponding information based on the instruction sent by the sender, or making a judgment and determining the required operation or requested result based on the judgment result.

[0062] It is worth noting that the technologies described in this application are not limited to Long Term Evolution (LTE) / LTE-Advanced (LTE-A) systems, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency-Division Multiple Access (SC-FDMA), or other systems. The terms "system" and "network" in this application are often used interchangeably, and the described technologies can be used with the systems and radio technologies mentioned above, as well as with other systems and radio technologies. The following description describes New Radio (NR) systems for illustrative purposes, and the term NR is used in most of the following description; however, these technologies can also be applied to systems other than NR systems, such as 6th generation (6G) radio systems. th Generation 6G communication system.

[0063] Figure 1 shows a block diagram of a wireless communication system applicable to an embodiment of this application. The wireless communication system includes a terminal 11 and a network-side device 12. The terminal 11 can also be referred to as User Equipment (UE), and can be a mobile phone, tablet computer, laptop computer, notebook computer, personal digital assistant (PDA), handheld computer, netbook, ultra-mobile personal computer (UMPC), mobile internet device (MID), augmented reality (AR), virtual reality (VR) device, robot, wearable device, flight vehicle, vehicle user equipment (VUE), shipboard equipment, pedestrian user equipment (PUE), smart home (home devices with wireless communication capabilities, such as refrigerators, televisions, washing machines, or furniture), game console, personal computer (PC), ATM, or self-service machine, etc. Wearable devices include: smartwatches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart chains, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. Among these, in-vehicle devices can also be referred to as in-vehicle terminals, in-vehicle controllers, in-vehicle modules, in-vehicle components, in-vehicle chips, or in-vehicle units, etc. It should be noted that the specific type of terminal 11 is not limited in this application embodiment. Network-side equipment 12 may include access network equipment or core network equipment, wherein access network equipment may also be referred to as Radio Access Network (RAN) equipment, radio access network function, or radio access network unit. Access network equipment may include base stations, Wireless Local Area Network (WLAN) access points (APs), or Wireless Fidelity (WiFi) nodes, etc.Among them, base stations can be referred to as Node B (NB), Evolved Node B (eNB), Next Generation Node B (gNB), New Radio Node B (NR Node B), Access Point, Relay Base Station (RBS), Serving Base Station (SBS), Base Transceiver Station (BTS), Radio Base Station, Radio Transceiver, Basic Service Set (BSS), Extended Service Set (ESS), Home Node B (HNB), Home Evolved Node B, Transmit / Receive Point (TRP), Non-Terrestrial Network (NTN) equipment (such as satellite or high altitude platform stations). The term "base station" can be any suitable term in the field, such as "station" or any other appropriate term in the relevant field, as long as the same technical effect is achieved. The term "base station" is not limited to specific technical terms. It should be noted that the embodiments of this application only use the base station in the NR system as an example for introduction, and do not limit the specific type of base station.

[0064] Core network equipment, also known as core network nodes, core network functions, or core network elements, includes, but is not limited to, at least one of the following: Mobility Management Entity (MME), Access and Mobility Management Function (AMF), Session Management Function (SMF), User Plane Function (UPF), Policy Control Function (PCF), Policy and Charging Rules Function (PCRF), Edge Application Server Discovery Function (EASDF), Unified Data Management (UDM), Unified Data Repository (UDR), Home Subscriber Server (HSS), Centralized network configuration (CNC), Network Repository Function (NRF), Network Exposure Function (NEF), Local NEF (L-NEF), and Binding Support. Functions include BSF, Application Function (AF), Location Management Function (LMF), Gateway Mobile Location Centre (GMLC), Network Data Analytics Function (NWDAF), and Non-Terrestrial Network (NTN) equipment (such as satellite or high altitude platform station).It should be noted that the embodiments of this application only use the core network equipment in the NR system as an example for introduction, and do not limit the specific type of core network equipment. If the name of the core network equipment mentioned in the embodiments of this application changes in subsequent protocol versions (e.g., 6G), it is also within the scope of protection of this application.

[0065] Optionally, the core network equipment can be implemented by one or more functional modules in a single device, or by multiple devices working together; this application does not specifically limit this. It is understood that the aforementioned functional modules can be network elements in hardware devices, software functional modules running on dedicated hardware, or virtualized functional modules instantiated on a platform (e.g., a cloud platform).

[0066] The cell handover method or transmission failure handling method provided in this application will be described in detail below with reference to the accompanying drawings and through some embodiments and application scenarios.

[0067] In related technologies, in order to reduce the problem of excessive measurement reporting caused by periodic or semi-continuous reporting in traditional LTM, Conditional LTM (CLTM) is introduced. That is, by pre-defining execution events, when the event is met, the terminal does not perform measurement reporting, but directly performs LTM, that is, performs cell or beam handover process.

[0068] In Conditional LTM, an early uplink and downlink synchronization process also exists. The network sends a Physical Downlink Control Channel (PDCCH) command to the terminal, which then sends a preamble to the indicated candidate cell. After the entire process is completed, the network sends the Timing Advance (TA) to the terminal via the Media Access Control Control Element (MAC CE). The TA corresponds to a specific candidate cell. The terminal can obtain the TAs of multiple cells in advance. Once the terminal obtains the TA, it starts the corresponding TA timer. During the TA timer's operation, the TA of that cell is considered valid.

[0069] The terminal will evaluate based on the configuration of Conditional LTM. When the candidate cell or beam meets the conditions, Conditional LTM will be triggered. At this time, if the terminal believes that it has a valid TA, it can perform RACH-less to access the target cell.

[0070] As shown in Figure 2, this application embodiment provides a cell handover method, the method including:

[0071] Step 201: If the first condition is met, the terminal considers the RACH-less LTM cell switch to be ongoing.

[0072] In one implementation, "the terminal believes that RACH-less cell handover is in progress" can be understood as: the terminal starts the RACH-less cell handover process.

[0073] The first condition includes at least one of the following:

[0074] At the first moment of LTM triggering, the timing advance timer (TA) for the target cell is either running or has not timed out.

[0075] When the trigger condition LTM is executed, the terminal is configured with a Configured Grant (CG) resource;

[0076] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0077] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less, such as cg-RRC-Configuration (configuration authorization RRC configuration);

[0078] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0079] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources; for example, the first time period may include Xms or X time slots; in one implementation, the first time period may be the setting duration of the TA timer corresponding to the target cell.

[0080] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0081] Optionally, the target cell mentioned above is the cell corresponding to the target reference signal or beam selected by the terminal when the trigger condition LTM is executed.

[0082] In one implementation, "available configuration authorization resources" can be understood as configuration authorization resources associated with the target beam selected by the terminal. For example, if a configuration authorization resource exists, but it is not associated with the target beam selected by the terminal, but is associated with another beam, then the configuration authorization resource is considered unavailable.

[0083] In this embodiment of the application, when the terminal triggers the execution of conditional LTM, it determines whether a RACH-less cell handover is in progress based on a first condition. This allows the terminal to correctly determine when to use RACH-less during the execution of conditional LTM, enabling the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process. It also avoids the problem of the terminal using RACH-less when it cannot use it, which would lead to handover failure.

[0084] In an optional embodiment of this application, the method further includes:

[0085] If available configuration grant resources exist at the first moment of the execution of the LTM trigger condition, the start time of the RACH-less cell handover is determined to be the first moment. This embodiment can also be understood as follows: if available configuration grant resources exist at the first moment of the execution of the LTM trigger condition, the terminal considers that the RACH-less cell handover is in progress or has started on the configuration grant resources corresponding to the first moment.

[0086] In another optional embodiment of this application, the method further includes:

[0087] If no available configuration grant resource exists at the first moment when LTM execution is triggered, and the TA timer corresponding to the target cell at the time domain location of the first available configuration grant resource after the first moment has not expired, the start time of the RACH-less cell handover is determined to be the time corresponding to the first available configuration grant resource after the first moment. This embodiment can also be understood as follows: If no available configuration grant resource exists at the first moment when LTM execution is triggered, and the TA timer corresponding to the target cell at the time domain location of the first available configuration grant resource after the first moment has not expired, the terminal considers RACH-less cell handover to be in progress or to have started on the first available configuration grant resource after the first moment.

[0088] Optionally, if the TA timer corresponding to the target cell at the time-domain location of the first available configuration authorization resource after the first time point expires, the method further includes:

[0089] The terminal either performs a RACH-based cell handover at the first moment or considers the RACH-less process to have failed.

[0090] or,

[0091] The terminal performs a RACH-based cell handover or considers the RACH-less process to have failed after the TA timer expires.

[0092] As an optional embodiment, if the terminal considers the RACH-less process to have failed, the method further includes:

[0093] The terminal performs a fast recovery process, and / or the terminal performs an RRC connection re-establishment process.

[0094] In one implementation, after the terminal determines that the RACH-less process has failed, it directly executes the fast recovery process, or directly executes the RRC connection re-establishment process, or first attempts the fast recovery process, and if the recovery fails, executes the RRC connection re-establishment process.

[0095] The fast recovery process refers to the process where the terminal performs a cell reselection when the conditional LTM fails. If the selected cell is one of the candidate cells for conditional LTM, the terminal triggers the conditional LTM execution process again.

[0096] In summary, in this embodiment of the application, when the terminal triggers the execution of conditional LTM, it determines whether a RACH-less cell handover is in progress based on a first condition. This allows the terminal to correctly determine whether RACH-less is used during the execution of conditional LTM, enabling the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process. Furthermore, the terminal can determine the start time of the RACH-less cell handover based on whether the TA timer at the time domain location of the configured authorized resources has expired. This allows the terminal to correctly determine when to start the RACH-less process during the execution of conditional LTM, thereby increasing the handover success rate.

[0097] To more clearly describe the cell handover method provided in the embodiments of this application, two examples are given below.

[0098] Example 1

[0099] Step 1: The base station sends conditional LTM configuration to the terminal;

[0100] Step 2: The terminal performs a conditional LTM configuration assessment;

[0101] Step 3: The base station sends a PDCCH command (order) to the terminal. The terminal sends a preamble to the candidate cell. The candidate cell sends the TA to the source cell. The source cell sends the TA to the terminal. After receiving the TA, the terminal starts the first TA timer associated with the candidate cell.

[0102] Step 4: Terminal evaluation condition LTM, at least one beam satisfies the event triggering condition;

[0103] Step 5: The terminal triggers conditional LTM execution, selecting the first beam as the target beam.

[0104] Step 6: Based on the remaining duration of the first TA timer associated with the target cell (the candidate cell where the target beam is located) and the location of the next or most recent available configuration authorization resource, the terminal determines whether the first TA timer will time out when the next or most recent available configuration authorization resource arrives.

[0105] Step 7a: If the terminal determines that the first TA timer has not expired, the terminal executes the RACH-less procedure (consider the RACH-less LTM cell switch to be ongoing).

[0106] Step 7b: If the terminal determines that a timeout has occurred, the terminal performs one of the following actions:

[0107] If the RACH-less process fails, execute a fast recovery or reconstruction process.

[0108] Perform a RACH-based process;

[0109] Among them, steps 7a and 7b are two cases, and only one of them can be satisfied.

[0110] Example 2

[0111] Step 1: The base station sends conditional LTM configuration to the terminal;

[0112] Step 2: The terminal performs a conditional LTM configuration assessment;

[0113] Step 3: The base station sends a PDCCH command (order) to the terminal. The terminal sends a preamble to the candidate cell. The candidate cell sends the TA to the source cell. The source cell sends the TA to the terminal. After receiving the TA, the terminal starts the first TA timer associated with the candidate cell.

[0114] Step 4: Terminal evaluation condition LTM, at least one beam satisfies the event triggering condition;

[0115] Step 5: The terminal triggers conditional LTM execution, selecting the first beam as the target beam.

[0116] Step 6: The terminal determines whether the first TA timer associated with the target cell (the candidate cell where the target beam is located) has expired. If it has not expired, the terminal considers that the RACH-less process is in progress.

[0117] Step 7: After the terminal waits for the next or most recent available configuration authorization resource, it checks again whether the first TA timer has timed out. If it has not timed out, the terminal considers the RACH-less process to be in progress. If it has timed out, the terminal considers the RACH-less process to have failed and performs a fast recovery or reconstruction process.

[0118] In this embodiment, when the terminal triggers the execution of Conditional LTM, it determines whether a RACH-less cell handover is in progress based on a first condition. This allows the terminal to correctly determine whether RACH-less is used during the execution of Conditional LTM, enabling the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process. Furthermore, the terminal can determine the start time of the RACH-less cell handover based on whether the TA timer at the time domain location of the configured authorized resources has expired. This allows the terminal to correctly determine when to start the RACH-less process during the execution of Conditional LTM, thereby increasing the handover success rate.

[0119] As shown in Figure 3, this application embodiment also provides a transmission failure handling method, the method further comprising:

[0120] Step 301: If the second condition is met, the terminal performs the first action; the second condition includes: the uplink transmission performed by the terminal on the target configuration grant resource fails, or the retransmission timer of the target grant resource (such as the configuration grant RRC retransmission timer, cg-RRC-RetransmissionTimer) times out, or the timer of the target grant resource times out (such as the configuration grant timer, configuredGrantTimer); optionally, meeting the second condition can be understood as the terminal determining that a CG transmission failure has occurred on the target configuration grant resource.

[0121] The first behavior includes at least one of the following:

[0122] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0123] Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

[0124] Optionally, the value of N can be determined by network configuration, pre-agreed terms, or protocol agreement.

[0125] For example, when N equals 1, the first action includes: performing an uplink transfer on one configuration authorization resource following the target configuration authorization resource.

[0126] Optionally, if the network side is configured to allow conditional LTM attempts, the first action includes: performing uplink transmissions on N configuration authorized resources following the target configuration authorized resource.

[0127] In some embodiments, if the first uplink transmission of the authorized resource fails, and if the network side is configured to allow CLTM attempts, the UE will attempt at most one more time. If it still fails, then RACH-less is considered to have failed.

[0128] In one implementation, the uplink transmission includes at least one of the following: uplink transmission related to cell handover without RACH, uplink transmission related to conditional LTM, uplink transmission related to conditional handover (CHO), and uplink transmission related to conditional primary / secondary cell addition or change (CPAC).

[0129] In another implementation, the above-mentioned configuration authorization resources (which can be the target configuration authorization resource or the above N configuration authorization resources) can be used for at least one of the following uplink transmissions: uplink transmissions related to cell handover without RACH, uplink transmissions related to conditional LTM, uplink transmissions related to conditional handover (CHO), and uplink transmissions related to conditional primary / secondary cell addition or change (CPAC).

[0130] In some embodiments, if the uplink transmission performed on the target configuration authorized resource is an uplink transmission corresponding to Conditional LTM, before step 301, the method further includes: if a first condition is met, the terminal considers the RACH-less LTM cell switch to be ongoing.

[0131] The first condition includes at least one of the following:

[0132] At the first moment of LTM triggering, the timing advance timer (TA) for the target cell is either running or has not timed out.

[0133] When the trigger condition LTM is executed, the terminal is configured with a Configured Grant (CG) resource;

[0134] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0135] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less, such as cg-RRC-Configuration (configuration authorization RRC configuration);

[0136] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0137] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources; for example, the first time period may include Xms or X time slots; in one implementation, the first time period may be the setting duration of the TA timer corresponding to the target cell.

[0138] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0139] In this embodiment of the application, when the terminal determines that a CG transmission failure has occurred on the target configuration authorized CG resource, the terminal performs the first action, thereby enabling the retransmission of uplink transmissions related to the RACH-less process, allowing the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process; or, if the RACH-less process fails, it performs a fast recovery or reconstruction process or changes to a RACH-based cell handover process to improve the cell handover success rate.

[0140] In at least one embodiment of this application, performing the first operation includes:

[0141] If the TA timer at the time domain position of N configuration authorization resources following the target configuration authorization resource times out, the first operation is performed.

[0142] In one implementation, before the terminal performs the first operation, it needs to determine whether the TA timer at the time domain position of the N configuration authorization resources after the target configuration authorization resource has timed out; if it has timed out, the first operation is performed.

[0143] In another implementation, the terminal directly executes the first operation.

[0144] It should be noted that the specific content of the first operation can be determined by the base station configuration or based on a pre-agreed agreement. For example, the base station may configure the first operation to perform fast recovery or reconstruction (in which case the terminal considers the RACH-less process to have failed); another example is that the first operation may be pre-agreed to perform RACH-based cell handover.

[0145] In at least one optional embodiment of this application, performing uplink transmission on N configuration authorization resources following the target configuration authorization resource includes:

[0146] If the TA timer at the time domain position of N configuration authorized resources following the target configuration authorized resource does not time out, uplink transmission is performed on the N configuration authorized resources.

[0147] In one implementation, before the terminal performs an upload transmission on the N configuration authorized resources, it needs to determine whether the TA timer at the time domain position of the N configuration authorized resources after the target configuration authorized resource has expired; if it has not expired, then the uplink transmission is performed on the N configuration authorized resources after the target configuration authorized resource.

[0148] In another implementation, the terminal directly performs uplink transmission on N configuration authorization resources following the target configuration authorization resource.

[0149] As an optional embodiment, the method further includes:

[0150] At the moment when the second condition is met, determine whether the TA timer at the time domain position of the N configuration authorization resources after the target configuration authorization resource has timed out;

[0151] or,

[0152] At the time domain positions of N configuration authorized resources following the target configuration authorized resource, determine whether the TA timer at the time domain position of the N configuration authorized resources has timed out.

[0153] In other words, in this embodiment of the application, the terminal can directly execute the first action after the second condition is met, or the terminal can determine whether the TA timer at the time domain location of the N configuration authorized resources has timed out after the second condition is met, and execute the corresponding first action according to the determination result.

[0154] In at least one embodiment of this application, performing the first operation includes:

[0155] At the moment when the second condition is met, the first operation is executed;

[0156] or,

[0157] The first operation is performed at the time-domain location of N configuration authorization resources following the target configuration authorization resource.

[0158] In this embodiment, when the first action includes performing the first operation, the terminal immediately performs the first operation when it determines that the second condition is met; or the terminal performs the first operation at the time domain position of N configuration authorization resources after determining that the second condition is met.

[0159] Continuing with the previous example, if the first line includes: performing uplink transmissions on N configuration authorization resources following the target configuration authorization resource, the method further includes:

[0160] If an uplink transmission fails on N configuration authorized resources following the target configuration authorized resource, the terminal performs the first operation;

[0161] or,

[0162] If an uplink transmission fails on N configuration authorized resources following the target configuration authorized resource, the terminal performs the first action.

[0163] In one implementation, this application embodiment allows uplink retransmission after multiple configuration grant transmission failures. That is, if uplink transmission still fails on N configuration grant resources, the terminal continues to perform a first action, which includes: continuing uplink transmission on N configuration grant resources after the configuration grant resource where the transmission failure occurred; and / or performing a first operation, which includes: considering the RACH-less process as failed, or performing RACH-based cell handover.

[0164] In another implementation, this application embodiment allows uplink retransmission at most once after a configuration authorization transmission failure. That is, if the uplink transmission on a configuration authorization resource still fails, the terminal directly performs the first operation.

[0165] Alternatively, the implementation method described above can be indicated by base station configuration or determined based on a pre-agreed agreement. That is, the terminal decides how many uplink retransmissions to perform based on base station configuration or a pre-agreed agreement.

[0166] As an optional embodiment, if the terminal considers the RACH-less process to have failed, the method further includes:

[0167] The terminal performs a fast recovery process, and / or the terminal performs an RRC connection re-establishment process.

[0168] In one implementation, after the terminal determines that the RACH-less process has failed, it directly executes the fast recovery process, or directly executes the RRC connection re-establishment process, or first attempts the fast recovery process, and if the recovery fails, executes the RRC connection re-establishment process.

[0169] The fast recovery process refers to the process where the terminal performs a cell reselection when the conditional LTM fails. If the selected cell is one of the candidate cells for conditional LTM, the terminal triggers the conditional LTM execution process again.

[0170] In summary, in the embodiments of this application, when the terminal determines that a CG transmission failure has occurred on the target configuration authorized CG resource, the terminal executes the first action, thereby enabling the retransmission of uplink transmissions related to the RACH-less process, allowing the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process; or, if the RACH-less process fails, it executes a fast recovery or reconstruction process or changes to a RACH-based cell handover process to improve the cell handover success rate.

[0171] To more clearly describe the cell handover method provided in the embodiments of this application, two examples are given below.

[0172] Example 1

[0173] Step 1: The base station sends conditional LTM configuration to the terminal;

[0174] Step 2: The terminal performs a conditional LTM configuration assessment;

[0175] Step 3: The base station sends a PDCCH command (order) to the terminal. The terminal sends a preamble to the candidate cell. The candidate cell sends the TA to the source cell. The source cell sends the TA to the terminal. After receiving the TA, the terminal starts the first TA timer associated with the candidate cell.

[0176] Step 4: Terminal evaluation condition LTM, at least one beam satisfies the event triggering condition;

[0177] Step 5: The terminal triggers conditional LTM execution, selecting the first beam as the target beam.

[0178] Step 6: The terminal determines whether the first TA timer associated with the target cell (the candidate cell where the target beam is located) has timed out. If it has not timed out, the terminal considers that the RACH-less process is in progress.

[0179] Step 7: The terminal performs uplink transmission at the configured authorized resources. If uplink transmission fails, the terminal performs at least one of the following actions:

[0180] The next configuration authorization resource still considers the RACH-less process to be in progress and continues to attempt to transfer;

[0181] In the next configuration authorization resource, it is determined whether the first TA timer has timed out. If it has timed out, the terminal performs the first operation, which includes one of the following:

[0182] If the RACH-less process fails, execute a fast recovery or reconstruction process.

[0183] It becomes a RACH-based process;

[0184] At this point, the system checks whether the first TA timer has timed out at the next configuration authorization resource. If it has timed out, the terminal executes one of the first operations.

[0185] Execute one of the first operations directly.

[0186] In this embodiment of the application, when the terminal determines that a CG transmission failure has occurred on the target configuration authorized CG resource, the terminal performs the first action, thereby enabling the retransmission of uplink transmissions related to the RACH-less process, allowing the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process; or, if the RACH-less process fails, it performs a fast recovery or reconstruction process or changes to a RACH-based cell handover process to improve the cell handover success rate.

[0187] The cell handover method or transmission failure handling method provided in this application can be executed by a cell handover device or a transmission failure handling device. This application uses the execution of the cell handover method or transmission failure handling method by a cell handover device or a transmission failure handling device as an example to illustrate the cell handover device or transmission failure handling device provided in this application.

[0188] This application provides a cell handover device or a transmission failure handling device. As an example, the cell handover device or transmission failure handling device can be a communication device or a component in a communication device, such as a chip. The communication device can be a terminal, a network-side device, or a server, etc. Exemplarily, the terminal can be, but is not limited to, the type of terminal 11 listed above, and the network-side device can be, but is not limited to, the type of network-side device 12 listed above. This application does not impose specific limitations.

[0189] A cell handover device or transmission failure handling device includes a receiving module, a transmitting module, and a processing module. These modules can be implemented in software or hardware. When implemented in hardware, the processing module can be implemented by a processor. For example, the processor can include general-purpose processors, special-purpose processors, etc., such as a Central Processing Unit (CPU), microprocessor, Digital Signal Processor (DSP), Artificial Intelligence (AI) processor, Graphics Processing Unit (GPU), Application Specific Integrated Circuit (ASIC), Network Processor (NP), Field Programmable Gate Array (FPGA), or other programmable logic devices, gate circuits, transistors, discrete hardware components, etc. The receiving and transmitting modules can be implemented by a communication interface, which can include one or more of the following: transceiver, pins, circuits, bus, radio frequency unit, etc.

[0190] Specifically, referring to Figure 4, when the cell handover device is a terminal or a component within a terminal, the cell handover device includes:

[0191] The first processing module 401 is configured to consider a cell handover without a random access channel (RACH-less) to be in progress if a first condition is met; wherein the first condition includes at least one of the following:

[0192] At the first moment of LTM triggering, the timing advance timer (TA) for the target cell is either running or has not timed out.

[0193] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources;

[0194] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0195] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less;

[0196] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0197] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources;

[0198] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0199] In some embodiments, the apparatus further includes:

[0200] The second processing module is used to determine the start time of the RACH-less cell handover as the first moment if there are available configuration authorization resources at the first moment of the LTM triggering condition execution.

[0201] And / or,

[0202] The third processing module is used to determine the start time of the RACH-less cell handover as the time corresponding to the first available configuration authorization resource after the first time if there is no available configuration authorization resource at the first moment of LTM execution and the TA timer of the target cell at the time domain location of the first available configuration authorization resource after the first time has not expired.

[0203] In some embodiments, the apparatus further includes:

[0204] The fourth processing module is used to perform RACH-based cell handover or consider the RACH-less process to have failed if the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first time expires.

[0205] And / or,

[0206] The fifth processing module is used to perform RACH-based cell handover or consider the RACH-less process to have failed if the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first time expires.

[0207] In some embodiments, the apparatus further includes:

[0208] The tenth processing module is used to perform a fast recovery process and / or an RRC connection re-establishment process if the terminal considers the RACH-less process to have failed.

[0209] In this embodiment, when the terminal triggers the execution of Conditional LTM, it determines whether a RACH-less cell handover is in progress based on a first condition. This allows the terminal to correctly determine whether RACH-less is used during the execution of Conditional LTM, enabling the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process. Furthermore, the terminal can determine the start time of the RACH-less cell handover based on whether the TA timer at the time domain location of the configured authorized resources has expired. This allows the terminal to correctly determine when to start the RACH-less process during the execution of Conditional LTM, thereby increasing the handover success rate.

[0210] It should be noted that the cell handover device provided in this application is a device capable of performing the above-described cell handover method. Therefore, all embodiments of the above-described cell handover method are applicable to this device and can achieve the same or similar beneficial effects, which will not be repeated here.

[0211] Specifically, referring to Figure 5, when the transmission failure handling device is a terminal or a component within a terminal, the transmission failure handling device includes:

[0212] The sixth processing module 501 is used to execute the first action when the second condition is met; the second condition includes: the uplink transmission performed by the terminal on the target configuration authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out;

[0213] The first action includes at least one of the following:

[0214] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0215] Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

[0216] In some embodiments, the triggering conditions for performing the first operation include:

[0217] The TA timer times out at the time-domain location of the N configuration authorized resources following the target configuration authorized resource.

[0218] In some embodiments, the triggering conditions for performing uplink transmissions on N configuration authorization resources following the target configuration authorization resource include:

[0219] The TA timer at the time domain location of the N configuration authorization resources following the target configuration authorization resource does not time out.

[0220] In some embodiments, when N equals 1, the first action includes performing an uplink transfer on one configuration authorization resource following the target configuration authorization resource.

[0221] In some embodiments, where the network side is configured to allow conditional LTM attempts, the first action includes: performing uplink transmissions on N configuration authorization resources following the target configuration authorization resource.

[0222] In some embodiments, the time-domain location where the first operation is performed includes:

[0223] The moment when the second condition is met;

[0224] or,

[0225] The temporal location of the N configuration authorization resources following the target configuration authorization resource.

[0226] In some embodiments, the apparatus further includes:

[0227] The seventh processing module is used to determine, at the moment when the second condition is met, whether the TA timer at the time domain position of the N configuration authorization resources after the target configuration authorization resource has timed out;

[0228] And / or,

[0229] The eighth processing module is used to determine whether the TA timer at the time domain position of the N configuration authorized resources after the target configuration authorized resource has timed out.

[0230] In some embodiments, the apparatus further includes:

[0231] The ninth processing module is configured to perform the first operation in the event that an uplink transmission fails on N configuration authorized resources following the target configuration authorized resource.

[0232] In some embodiments, the apparatus further includes:

[0233] The eleventh processing module is used to execute a fast recovery process and / or an RRC connection re-establishment process if the terminal considers the RACH-less process to have failed.

[0234] In this embodiment of the application, when the terminal determines that a CG transmission failure has occurred on the target configuration authorized CG resource, the terminal performs the first action, thereby enabling the retransmission of uplink transmissions related to the RACH-less process, allowing the terminal to reduce the latency of accessing the target cell and increase the handover success rate through the RACH-less process; or, if the RACH-less process fails, it performs a fast recovery or reconstruction process or changes to a RACH-based cell handover process to improve the cell handover success rate.

[0235] It should be noted that the transmission failure processing device provided in this application embodiment is a device capable of executing the above-described transmission failure processing method. Therefore, all embodiments of the above-described transmission failure processing method are applicable to this device and can achieve the same or similar beneficial effects, which will not be repeated here.

[0236] The cell handover device or transmission failure processing device provided in this application embodiment can implement the various processes implemented in the method embodiments of Figures 2 to 3 and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0237] As shown in Figure 6, this application embodiment also provides a communication device 600, including a processor 601 and a memory 602. The memory 602 stores a program or instructions that can run on the processor 601. For example, when the communication device 600 is a terminal, when the program or instructions are executed by the processor 601, they implement the various steps of the above-described cell handover method or transmission failure handling method embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0238] This application also provides a terminal, including a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the steps in the method embodiments shown in FIG2 or FIG3. This terminal embodiment corresponds to the above-described terminal-side method embodiments, and all implementation processes and methods of the above-described method embodiments can be applied to this terminal embodiment and can achieve the same technical effect. The terminal can be the device shown in FIG4 or FIG5. Specifically, FIG7 is a schematic diagram of the hardware structure of a terminal implementing an embodiment of this application.

[0239] The terminal 700 includes, but is not limited to, at least some of the following components: radio frequency unit 701, network module 702, audio output unit 703, input unit 704, sensor 705, display unit 706, user input unit 707, interface unit 708, memory 709, and processor 710.

[0240] Those skilled in the art will understand that the terminal 700 may also include a power supply (such as a battery) for powering various components. The power supply can be logically connected to the processor 710 through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system. The terminal structure shown in Figure 7 does not constitute a limitation on the terminal. The terminal may include more or fewer components than shown, or combine certain components, or have different component arrangements, which will not be elaborated here.

[0241] It should be understood that, in this embodiment, the input unit 704 may include a graphics processor 7041 and a microphone 7042. The graphics processor 7041 processes image data of still images or videos obtained by an image capture device (such as a camera) in video capture mode or image capture mode. The display unit 706 may include a display panel 7061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 707 includes at least one of a touch panel 7071 and other input devices 7072. The touch panel 7071 is also called a touch screen. The touch panel 7071 may include a touch detection device and a touch controller. Other input devices 7072 may include, but are not limited to, physical keyboards, function keys (such as volume control buttons, power buttons, etc.), trackballs, mice, and joysticks, which will not be described in detail here.

[0242] In this embodiment, after receiving downlink data from the network-side device, the radio frequency unit 701 can transmit it to the processor 710 for processing; in addition, the radio frequency unit 701 can send uplink data to the network-side device. Typically, the radio frequency unit 701 includes, but is not limited to, antennas, amplifiers, transceivers, couplers, low-noise amplifiers, duplexers, etc.

[0243] The memory 709 can be used to store software programs or instructions, as well as various data. The memory 709 may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory 709 may include volatile memory or non-volatile memory. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory 709 in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0244] Processor 710 may include one or more processing units; optionally, processor 710 integrates an application processor and a modem processor, wherein the application processor mainly handles operations involving the operating system, user interface, and applications, and the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into processor 710.

[0245] The processor 710 is configured to consider a RACH-less cell handover to be in progress if a first condition is met; wherein the first condition includes at least one of the following:

[0246] At the first moment of the execution of Mobility LTM triggered by Layer 1 or Layer 2, the Time Advance (TA) timer corresponding to the target cell is running or has not timed out;

[0247] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources;

[0248] When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources;

[0249] When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less;

[0250] At the first moment of the LTM trigger execution, there are available configuration authorization resources;

[0251] Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources;

[0252] On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

[0253] Alternatively, the processor 710 is further configured to perform the first action if a second condition is met; the second condition includes: the uplink transmission performed by the terminal on the target configuration authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out.

[0254] The first action includes at least one of the following:

[0255] Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1;

[0256] Perform a first operation; the first operation includes: performing fast recovery or reconstruction, or performing RACH-based cell handover.

[0257] It is understood that the implementation process of each implementation method mentioned in this embodiment can refer to the relevant description of the method embodiment and achieve the same or corresponding technical effect. To avoid repetition, it will not be described again here.

[0258] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described cell handover method or transmission failure handling method embodiments and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0259] The processor mentioned above is either the processor in the terminal described in the above embodiments or the processor in the network-side device. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk. In some examples, the readable storage medium may be a non-transient readable storage medium.

[0260] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface and the processor are coupled. The processor is used to run programs or instructions to implement the various processes of the above-described cell handover method or transmission failure handling method embodiments, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0261] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0262] This application also provides a computer program / program product, which is stored in a storage medium and executed by at least one processor to implement the various processes of the above-described cell handover method or transmission failure handling method embodiments, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0263] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0264] From the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of computer software products plus necessary general-purpose hardware platforms, and of course, they can also be implemented by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, magnetic disk, optical disk, etc.), and the computer software product includes several instructions to cause the terminal or network-side device to execute the methods described in the various embodiments of this application.

[0265] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other implementations under the guidance of this application without departing from the spirit and scope of the claims. All of these implementations are within the protection scope of this application.

Claims

1. A cell handover method, the method comprising: If the first condition is met, the terminal believes that a cell handover without a random access channel (RACH-less) is in progress; wherein the first condition includes at least one of the following: At the first moment of the execution of Mobility LTM triggered by Layer 1 or Layer 2, the Time Advance (TA) timer corresponding to the target cell is running or has not timed out; When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources; When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources; When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less; At the first moment of the LTM trigger execution, there are available configuration authorization resources; Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources; On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

2. The method according to claim 1, further comprising: If available configuration authorization resources exist at the first moment of LTM execution, the start time of the RACH-less cell handover is determined to be the first moment; or, If no available configuration authorization resource exists at the first moment when LTM execution is triggered, and if the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first moment has not expired, the start time of the RACH-less cell handover is determined to be the time corresponding to the first available configuration authorization resource after the first moment.

3. The method according to claim 2, wherein, If the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first time point expires, the method further includes: The terminal either performs a RACH-based cell handover at the first moment or considers the RACH-less process to have failed. or, The terminal performs a RACH-based cell handover or considers the RACH-less process to have failed after the TA timer expires.

4. The method according to claim 3, wherein, If the terminal considers the RACH-less process to have failed, the method further includes: The terminal performs a fast recovery process, and / or the terminal performs an RRC connection re-establishment process.

5. A method for handling transmission failures, the method comprising: If the second condition is met, the terminal performs the first action; The second condition includes: the uplink transmission performed by the terminal on the target authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out; The first action includes at least one of the following: Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1; Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

6. The method according to claim 5, wherein, The execution of the first operation includes: If the TA timer at the time domain position of N configuration authorization resources following the target configuration authorization resource times out, the first operation is performed.

7. The method according to claim 5, wherein, Performing uplink transmissions on N configuration authorization resources following the target configuration authorization resource includes: If the TA timer at the time domain position of N configuration authorized resources following the target configuration authorized resource does not time out, uplink transmission is performed on the N configuration authorized resources.

8. The method according to claim 5 or 7, wherein, When N equals 1, the first action includes: An uplink transfer is performed on one configuration authorization resource following the target configuration authorization resource.

9. The method according to claim 5, 7, or 8, wherein, If the network side is configured to allow conditional LTM attempts, the first action includes: performing uplink transmissions on N configuration authorized resources following the target configuration authorized resource.

10. The method according to claim 5 or 6, wherein, The execution of the first operation includes: At the moment when the second condition is met, the first operation is executed; or, The first operation is performed at the time-domain location of N configuration authorization resources following the target configuration authorization resource.

11. The method according to claim 6 or 7, further comprising: At the moment when the second condition is met, determine whether the TA timer at the time domain position of the N configuration authorization resources after the target configuration authorization resource has timed out; or, At the time domain positions of N configuration authorized resources following the target configuration authorized resource, determine whether the TA timer at the time domain position of the N configuration authorized resources has timed out.

12. The method according to claim 5, wherein, In the event that uplink transmissions performed on N configuration authorized resources following the target configuration authorized resource fail, the method further includes: The terminal performs the first operation; or, The terminal performs the first action.

13. The method according to any one of claims 5-12, wherein, If the terminal considers the RACH-less process to have failed, the method further includes: The terminal performs a fast recovery process, and / or the terminal performs an RRC connection re-establishment process.

14. A cell handover device, applied to a terminal, the device comprising: A first processing module is configured to consider a cell handover without a random access channel (RACH-less) to be in progress if a first condition is met; wherein the first condition includes at least one of the following: At the first moment of LTM triggering, the timing advance timer (TA) for the target cell is either running or has not timed out. When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources; When LTM is triggered, the target reference signal or beam selected by the terminal has associated configuration authorized resources; When the trigger condition LTM is executed, the terminal is configured with configuration authorization resources related to RACH-less; At the first moment of the LTM trigger execution, there are available configuration authorization resources; Within the first time period after the LTM trigger condition is executed, there are available configuration authorization resources; On the first available configuration authorization resource after the trigger condition LTM is executed, the TA timer corresponding to the target cell is running or has not timed out.

15. The apparatus of claim 14, further comprising: The second processing module is used to determine the start time of the RACH-less cell handover as the first moment if there are available configuration authorization resources at the first moment of the LTM triggering condition execution. And / or, The third processing module is used to determine the start time of the RACH-less cell handover as the time corresponding to the first available configuration authorization resource after the first time if there is no available configuration authorization resource at the first moment of LTM execution and the TA timer of the target cell at the time domain location of the first available configuration authorization resource after the first time has not expired.

16. The apparatus of claim 15, further comprising: The fourth processing module is used to perform RACH-based cell handover or consider the RACH-less process to have failed if the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first time expires. And / or, The fifth processing module is used to perform RACH-based cell handover or consider the RACH-less process to have failed if the TA timer corresponding to the target cell at the time domain location of the first available configuration authorization resource after the first time expires.

17. The apparatus of claim 16, further comprising: The tenth processing module is used to perform a fast recovery process and / or an RRC connection re-establishment process if the terminal considers the RACH-less process to have failed.

18. A transmission failure handling apparatus, the apparatus comprising: The sixth processing module is used to execute the first action if the second condition is met; The second condition includes: the uplink transmission performed by the terminal on the target authorized resource fails, or the retransmission timer of the target authorized resource times out, or the timer of the target authorized resource times out; The first action includes at least one of the following: Uplink transmission is performed on N configuration authorized resources following the target configuration authorized resource; N is an integer greater than or equal to 1; Perform a first operation; the first operation includes: deeming the RACH-less process to have failed, or performing a RACH-based cell handover.

19. The apparatus according to claim 18, wherein, The triggering conditions for executing the first operation include: The TA timer times out at the time-domain location of the N configuration authorized resources following the target configuration authorized resource.

20. The apparatus according to claim 18, wherein, The triggering conditions for performing uplink transmissions on N configuration authorization resources following the target configuration authorization resource include: The TA timer at the time domain location of the N configuration authorization resources following the target configuration authorization resource does not time out.

21. The apparatus according to claim 18 or 20, wherein, When N equals 1, the first action includes: An uplink transfer is performed on one configuration authorization resource following the target configuration authorization resource.

22. The apparatus according to claim 18, 20, or 21, wherein, If the network side is configured to allow conditional LTM attempts, the first action includes: performing uplink transmissions on N configuration authorized resources following the target configuration authorized resource.

23. The apparatus according to claim 18 or 19, wherein, The time-domain locations where the first operation is performed include: The moment when the second condition is met; or, The temporal location of the N configuration authorization resources following the target configuration authorization resource.

24. The apparatus according to claim 19 or 20, further comprising: The seventh processing module is used to determine, at the moment when the second condition is met, whether the TA timer at the time domain position of the N configuration authorization resources after the target configuration authorization resource has timed out; And / or, The eighth processing module is used to determine whether the TA timer at the time domain position of the N configuration authorized resources after the target configuration authorized resource has timed out.

25. The apparatus of claim 18, further comprising: The ninth processing module is configured to perform the first operation or the first action in the event that an uplink transmission fails on N configuration authorized resources following the target configuration authorized resource.

26. The apparatus according to any one of claims 18-25, further comprising: The eleventh processing module is used to execute a fast recovery process and / or an RRC connection re-establishment process if the terminal considers the RACH-less process to have failed.

27. A terminal, comprising a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the cell handover method as claimed in any one of claims 1 to 4, or implementing the steps of the transmission failure handling method as claimed in any one of claims 5 to 13.

28. A readable storage medium storing a program or instructions that, when executed by a processor, implement the cell handover method as described in any one of claims 1 to 4, or the steps of the transmission failure handling method as described in any one of claims 5 to 13.

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