Cell handover method, apparatus and terminal

Abstract

The application discloses a cell switching method, device and terminal, and belongs to the technical field of communication. The cell switching method of the application embodiment comprises the following steps: a terminal receives first configuration information, the first configuration information comprises at least one of the following: information indicating a candidate cell, information indicating support for a cell fast recovery function; and the terminal performs a first operation according to the first configuration information in the case of a radio link failure or a failure to switch to a first cell, the first operation comprising at least one of the following: if configuration information of a source cell in the process of switching to the first cell is saved, performing cell fast recovery for a second cell; if key change or packet data convergence protocol (PDCP) reestablishment needs to be performed in the process of switching to the second cell, performing cell fast recovery for the second cell; and if key change or PDCP reestablishment is not performed in the process of switching to the first cell, performing cell fast recovery for the second cell.

Description

Technical Field

[0001] This application belongs to the field of communication technology, specifically relating to a cell handover method, apparatus and terminal. Background Technology

[0002] In related technologies, when the network-side equipment is configured with a fast recovery function for the terminal, if the terminal selects a pre-configured handover candidate cell in the event of a handover failure or radio link failure (RLF), the terminal can perform a handover to replace radio resource control (RRC) reconstruction, thereby achieving the purpose of quickly restoring the connection.

[0003] After a handover failure or RLF (Recurrent Link Failure), the terminal will perform Packet Data Convergence Protocol (PDCP) reconstruction and Radio Link Control (RLC) reconstruction. During this process, the protocol state variables and cached data packets of the PDCP and RLC entities will be reset or cleared, making it difficult for the terminal to recover quickly in certain scenarios. In related technologies, directly attempting a rapid recovery after a handover failure or RLF can lead to a higher probability of network connection failure. Summary of the Invention

[0004] This application provides a cell handover method, apparatus, and terminal that can solve the problem of a high probability of terminal network connection failure.

[0005] Firstly, a cell handover method is provided, executed by a terminal, the method comprising:

[0006] The terminal receives first configuration information, which includes at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0007] In the event of a wireless link failure or a failure to hand over to the first cell, the terminal performs a first operation based on the first configuration information. The first operation includes at least one of the following:

[0008] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0009] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0010] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0011] The first cell or the second cell is one of the candidate cells.

[0012] Secondly, a cell handover device is provided, comprising:

[0013] A receiving module is configured to receive first configuration information, the first configuration information including at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0014] The processing module is configured to perform a first operation based on the first configuration information in the event of a radio link failure or a failure to handover to the first cell, wherein the first operation includes at least one of the following:

[0015] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0016] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0017] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0018] The first cell or the second cell is one of the candidate cells.

[0019] Thirdly, a cell handover apparatus is provided, the apparatus being configured to perform the steps of the method described in the first aspect.

[0020] Fourthly, 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.

[0021] Fifthly, a terminal is provided, including a processor and a communication interface, wherein,

[0022] A communication interface is used to receive first configuration information, the first configuration information including at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0023] The processor is configured to perform a first operation based on the first configuration information in the event of a radio link failure or a failure to handover to the first cell, the first operation including at least one of the following:

[0024] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0025] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0026] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0027] The first cell or the second cell is one of the candidate cells.

[0028] In a sixth aspect, 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.

[0029] A seventh aspect provides a wireless communication system, comprising: a terminal and a network-side device, wherein the terminal can be used to perform the steps of the method described in the first aspect.

[0030] Eighthly, a chip is provided, the chip including a processor and a communication interface coupled to the processor, the processor being used to run programs or instructions to implement the steps of the method as described in the first aspect.

[0031] In a ninth 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 method as described in the first aspect.

[0032] In this embodiment, the terminal, based on the first configuration information, performs a first operation in the event of a wireless link failure or a failure to handover to the first cell. The first operation includes: if the configuration information of the source cell during the handover to the first cell is stored, then performing fast cell recovery for the second cell, thereby enabling the terminal to quickly recover using the stored source cell configuration information, reducing the probability of network connection failure; or, the first operation includes: if a key change or PDCP reconstruction is required during the handover to the second cell, then performing fast cell recovery for the second cell; and / or, if no key change or PDCP reconstruction is performed during the handover to the first cell, then performing fast cell recovery for the second cell. Thus, by limiting the conditions for the terminal to perform fast recovery, the terminal can decide whether the scenario meets the requirements for fast recovery, thereby reducing the probability of network connection failure. Attached Figure Description

[0033] Figure 1 This is a block diagram of a wireless communication system applicable to embodiments of this application;

[0034] Figure 2a This is an architecture diagram of a CU-DU in related technologies;

[0035] Figure 2b This is one of the schematic diagrams of cell handover in related technologies;

[0036] Figure 2c This is the second schematic diagram of a cell handover process in related technologies;

[0037] Figure 2d This is the third illustration of a cell handover process in related technologies;

[0038] Figure 3 This is a flowchart of a cell handover process in related technologies;

[0039] Figure 4 This is one of the flowcharts of a cell handover method provided in the embodiments of this application;

[0040] Figure 5 This is a second flowchart of a cell handover method provided in the embodiments of this application;

[0041] Figure 6 This is the third flowchart of a cell handover method provided in the embodiments of this application;

[0042] Figure 7 This is a schematic diagram of the structure of a cell handover device provided in an embodiment of this application;

[0043] Figure 8 This is a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0044] Figure 9 This is a schematic diagram of the structure of a terminal provided in an embodiment of this application. Detailed Implementation

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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 in the systems and radio technologies mentioned above, as well as in 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) communication systems.

[0049] Figure 1This diagram illustrates a block diagram of a wireless communication system applicable to embodiments 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 devices (home appliances with wireless communication capabilities, such as refrigerators, televisions, washing machines, or furniture), game consoles, personal computers (PCs), ATMs, or self-service machines, etc. Wearable devices include: smartwatches, smart bracelets, smart earphones, 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, Transmission and Reception Point (TRP), and Non-Terrestrial Network (NTN) equipment (such as satellite or high altitude platform). 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 any specific technical term. 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.

[0050] 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 (such as 6G), it is also within the scope of protection of this application.

[0051] 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).

[0052] For ease of understanding, the following explains some aspects of the embodiments of this application:

[0053] 1. Centralized Unit (CU) - Distributed Unit (DU) Architecture

[0054] The NR access network splits the gNB into a central unit (gNB-CU) and distributed units (gNB-DU), which are connected via the F1 interface. The architecture diagram of the CU-DU is shown below. Figure 2a As shown.

[0055] One gNB contains only one CU, contains one or more DUs, and one DU contains one or more cells.

[0056] CU includes the Packet Data Convergence Protocol (PDCP) and above the protocol stack, while DU includes the protocol stack below the PDCP layer (such as Radio Link Control (RLC), Medium Access Control (MAC), and Physical Layer (PHY)).

[0057] In the control plane, the CU includes Radio Resource Control (RRC) and the PDCP of the control plane (PDCP-C);

[0058] On the user plane, the CU includes the Service Data Adaptation Protocol (SDAP) and the user plane PDCP (PDCP-U).

[0059] (1) Switching between Intra-CU and Intra-DU

[0060] This refers to the UE handing over between different cells within the same DU under the same CU, such as... Figure 2b As shown:

[0061] Figure 2b In this scenario, when a UE switches from cell 1 to cell 2 of DU1, the PDCP and RLC entities on the UE side are unaffected because the physical locations of the entities at each layer on the base station side remain unchanged. However, because the cell serving the UE has changed, the UE's MAC layer needs to be reset.

[0062] (2) Intra-CU, Inter-DU handover

[0063] That is, the UE switches between cells of different DUs under the same CU, such as Figure 2c As shown;

[0064] Figure 2c When a UE switches from a cell in DU1 to a cell in DU2, the MAC entity changes due to the changes in the RLC and MAC entities on the base station side. Therefore, the UE's RLC layer needs to be rebuilt, the MAC layer needs to be reset, and the PDCP layer needs to perform data recovery under AM bearer. Data packets that have not been fully transmitted are retransmitted in the PDCP layer.

[0065] (3) Inter-CU handover

[0066] That is, the UE switches between different CUs (i.e., different gNBs), such as Figure 2d As shown;

[0067] Figure 2d During the handover, the UE switches from DU1 of CU1 to DU2 of CU2. Therefore, the RLC layer needs to be rebuilt, the MAC layer needs to be reset, and key changes and PDCP reconstruction are required when switching across CUs.

[0068] 2. Layer 1 / Layer 2 Triggered Mobility (L1 / L2-triggered mobility, LTM)

[0069] To reduce handover latency, such as Figure 3 As shown, related technologies introduce LTM, where the network pre-configures multiple candidate cells for the UE. The DU, based on the Layer 1 measurement results reported by the UE, uses L1 / L2 signaling to instruct the UE to hand over to a suitable candidate cell. In one related technology, LTM only supports LTM handover within the same CU. In another related technology, LTM handover across CUs is supported.

[0070] 3. Conditional LTM (CLTM)

[0071] The relevant technology supports CLTM, which allows the UE to independently evaluate the handover execution conditions configured by the network. When the conditions are met, the UE hands over to the target cell. By avoiding the latency caused by measurement reporting and the network issuing handover commands, the robustness of the handover is improved. CLTM supports configuring handover execution conditions based on L1 or Layer 3 (L3) measurements.

[0072] 4. Conditional Handover (CHO)

[0073] Similar to CLTM, in order to prevent the UE from being unable to receive the handover command related messages from the source node after the channel conditions of the source cell deteriorate, thus causing handover failure, a conditional handover procedure is introduced in related technologies. CHO only supports handover execution conditions based on L3 measurement.

[0074] 5. Fast recovery

[0075] Intra-CU LTM, CHO, and CLTM all support fast recovery. That is, when the network is configured with fast recovery, in the event of a handover failure or radio link failure (RLF), if the UE selects a pre-configured handover candidate cell, the UE can perform a handover instead of RRC reconstruction, thereby achieving the purpose of fast connection recovery.

[0076] The following description, in conjunction with the accompanying drawings, details the cell handover method, apparatus, and related equipment provided in this application through some embodiments and application scenarios.

[0077] See Figure 4 , Figure 4 This is a flowchart of a cell handover method provided in an embodiment of this application, such as... Figure 4 As shown, the cell handover method includes the following steps:

[0078] Step 101: The terminal receives first configuration information, which includes at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0079] Step 102: Based on the first configuration information, in the event of a wireless link failure or failure to handover to the first cell, the terminal performs a first operation, the first operation including at least one of the following:

[0080] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0081] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0082] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0083] The first cell or the second cell is one of the candidate cells.

[0084] The configuration information of the source cell may include the configuration information of the PDCP entity of the source cell, the configuration information of the RLC entity of the source cell, and / or the configuration information of other protocol stack entities of the source cell; etc., which are not limited in this embodiment.

[0085] In addition, the configuration information of the source cell can be understood or replaced with the configuration information of the source master cell or source master cell group, such as the PDCP and / or RLC configuration of the source master cell or source master cell group.

[0086] In one embodiment, the cell fast recovery function can refer to the fact that after a cell handover failure or RLF occurs, if the RRC reconstruction target cell selected by the terminal is a configured candidate cell, the terminal can perform a handover instead of reconstruction to achieve fast recovery.

[0087] It should be noted that "community rapid recovery" can also be replaced with "rapid recovery".

[0088] In addition, performing fast cell recovery for the second cell can be replaced by performing fast recovery on the second cell.

[0089] It should be noted that when the first configuration information includes information indicating candidate cells, it can be understood that the network-side device configures handover candidate cells for the terminal. The candidate cells can be understood as or replaced with handover candidate cells.

[0090] Furthermore, the first configuration information can be sent via one or more signaling signals, and this embodiment does not limit this. For example, information indicating candidate cells or information indicating support for cell fast recovery function can be sent via the same signaling signal or via different signaling signals.

[0091] In one embodiment, the method further includes:

[0092] The terminal selects a cell, and the cell selected by the terminal is a second cell, which is a candidate cell configured for the terminal by the network-side device.

[0093] For example, before performing fast cell recovery for the second cell, the method further includes: the terminal selecting a cell, wherein the cell selected by the terminal is the second cell, and the second cell is a handover candidate cell configured by the network-side device for the terminal.

[0094] In one implementation, if no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell, which can be any candidate cell selected by the terminal. That is, if the terminal fails to handover to the first cell, and if no key change or PDCP reconstruction is performed during the handover, the terminal selects a cell. If the selected cell is any handover candidate cell, then fast recovery is performed.

[0095] In one implementation, the terminal performing a first operation may include:

[0096] The terminal executes the first operation according to the first rule;

[0097] The first rule includes at least one of the following:

[0098] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0099] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0100] The first cell or the second cell is one of the candidate cells.

[0101] In one implementation, if a radio link failure or handover to the first cell fails, and the terminal has already performed a key change or PDCP reconstruction during the handover to the first cell, the terminal selects a cell according to a preset priority rule. This preset priority rule allows the terminal to preferentially select cells that require key changes or PDCP reconstruction. For example, the preset priority rule includes: cells requiring key changes or PDCP reconstruction have a higher priority than cells that do not require key changes or PDCP reconstruction.

[0102] In one implementation, the candidate cells indicated by the information indicating candidate cells in the first configuration information may include inter-CU cells and / or intra-CU cells.

[0103] In one implementation, the candidate cells indicated by the information indicating candidate cells in the first configuration information may include inter-CU cells and intra-CU cells. Among the candidate cells indicated by the information indicating candidate cells, there are at least two inter-CU cells and at least two intra-CU cells.

[0104] Compared to related technologies where terminals can only be configured with inter-CU cells or intra-CU cells, the first configuration information allows terminals to be configured with both inter-CU and intra-CU cells as candidate cells simultaneously. This increases the types of candidate cells that the terminal can be configured with, enriches the handover scenarios for the terminal, and thus improves the probability of the terminal successfully connecting to the network.

[0105] It should be noted that the cell handover may include L3 handover (Handover, HO), CHO, LTM or other cell-changing handover methods triggered by network-side equipment.

[0106] Furthermore, the candidate cells indicated by the candidate cell information in the first configuration information can be candidate cells for L3 handover, CHO, LTM, or other changed cell handovers. Candidate cells for different types of handovers can be shared; for example, L3 handover or CHO can use LTM candidate cells for fast recovery.

[0107] In one implementation, during L3 handover or CHO, the terminal performs a first operation based on the first configuration information in the event of a radio link failure or failure to handover to the first cell. Compared to related technologies where L3 handover or CHO terminals can only be configured with inter-CU cells, the first configuration information allows the terminal to be configured with both inter-CU and intra-CU cells as candidate cells simultaneously, increasing the types of candidate cells that the terminal can be configured with.

[0108] In this embodiment of the application, the terminal performs a first operation based on the first configuration information in the event of a wireless link failure or a failure to hand over to the first cell. The first operation includes: if the configuration information of the source cell during the handover to the first cell is saved, then performing a fast cell recovery for the second cell, so that the terminal can use the saved configuration information of the source cell to perform a fast recovery, thereby reducing the probability of the terminal failing to connect to the network.

[0109] In this embodiment, the terminal performs a first operation based on the first configuration information in the event of a wireless link failure or a failure to handover to the first cell. The first operation includes: if a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then performing fast cell recovery for the second cell; and / or, if a key change or PDCP reconstruction is not performed during the handover to the first cell, then performing fast cell recovery for the second cell. In this way, by limiting the conditions for the terminal to perform fast recovery, the terminal can decide whether the scenario meets the requirements for performing fast recovery, thereby reducing the probability of the terminal failing to connect to the network.

[0110] Optionally, it also includes:

[0111] In the event of a radio link failure or a failure to handover to the first cell, a second operation is performed, the second operation including at least one of the following:

[0112] If the configuration information of the source cell is not saved during the handover to the first cell, then Radio Resource Control (RRC) reconstruction is performed.

[0113] If key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed.

[0114] In this implementation, if a radio link failure or handover to the first cell fails, and the configuration information of the source cell during the handover to the first cell is not saved, an RRC reconstruction is performed; thus, the access cell can be reconstructed via RRC when the terminal has not saved the configuration information of the source cell during the handover to the first cell.

[0115] In this implementation, if a wireless link failure or handover to the first cell fails, and if key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed. In this way, by having the terminal decide whether it meets the scenario for performing RRC reconstruction, the probability of the terminal failing to connect to the network can be reduced.

[0116] Optionally, it also includes:

[0117] During the process of switching to the first cell, the terminal saves the configuration information of the source cell.

[0118] In this embodiment, the configuration information of the source cell is saved during the cell handover process. The saved configuration information can be used to restore the configuration in the event of a cell handover failure. As a result, the terminal can use the saved configuration information of the source cell to quickly restore the cell, thereby reducing the probability of the terminal failing to connect to the network.

[0119] Optionally, if the configuration information of the source cell during the handover to the first cell is stored, then after performing fast cell recovery for the second cell, the method further includes:

[0120] The terminal releases the configuration information of the source cell.

[0121] In one implementation, when cell fast recovery is performed for the second cell and the handover to the second cell is successful, the terminal releases the saved configuration information of the source cell.

[0122] In one implementation, if the terminal successfully performs cell fast recovery for the second cell, the terminal releases the configuration information of the source cell; if the terminal fails to perform cell fast recovery for the second cell, the information is saved until the fast recovery is successful.

[0123] In this embodiment, after performing cell fast recovery for the second cell, the terminal releases the configuration information of the source cell, thereby reducing the terminal's memory overhead.

[0124] Optionally, if a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then a fast cell recovery is performed for the second cell, including:

[0125] If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and a key change or PDCP reconstruction is required during the handover process to the second cell, then cell fast recovery is performed for the second cell.

[0126] In this embodiment, if the terminal has already performed a key change or PDCP reconstruction during the handover to the first cell, and if a key change or PDCP reconstruction is required during the handover to the second cell, then cell fast recovery is performed for the second cell. In this way, by limiting the conditions for the terminal to perform fast recovery, the terminal can decide whether the scenario meets the requirements for performing fast recovery, thereby reducing the probability of the terminal failing to connect to the network.

[0127] Optionally, if key change or PDCP reconstruction is not required during the handover to the second cell, then performing RRC reconstruction includes:

[0128] If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and if a key change or PDCP reconstruction is not required during the handover process to the second cell, then an RRC reconstruction is performed.

[0129] In this embodiment, if the terminal has already performed a key change or PDCP reconstruction during the handover to the first cell, and if the handover to the second cell does not require a key change or PDCP reconstruction, then an RRC reconstruction is performed. In this way, by limiting the terminal to the condition that it cannot perform fast recovery and can only perform RRC reconstruction, the terminal can decide whether it meets the scenario that it cannot perform fast recovery and can only perform RRC reconstruction, thereby reducing the probability of the terminal failing to connect to the network.

[0130] Optionally, the method further includes:

[0131] In the event of a wireless link failure or failure to hand over to the first cell, if the terminal has performed a key change or PDCP reconstruction during the handover to the first cell, the terminal will select a cell according to a preset priority rule.

[0132] The preset priority rules include:

[0133] Cells that require key changes or PDCP reconstruction have a higher priority than cells that do not require key changes or PDCP reconstruction.

[0134] In this embodiment, if a wireless link failure or handover to the first cell fails, and the terminal has already performed a key change or PDCP reconstruction during the handover to the first cell, the terminal selects a cell according to a preset priority rule; thus, the terminal can preferentially select a cell suitable for fast recovery, thereby achieving the purpose of fast connection recovery.

[0135] Optionally, the method further includes:

[0136] The terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first information.

[0137] The first information includes at least one of the following:

[0138] The association identifier of the source cell and the association identifier of the target cell;

[0139] Whether the switching command includes information for key changes;

[0140] The first indication information is used to indicate whether a key change or PDCP reconstruction needs to be performed.

[0141] The source cell's association identifier can also be described as an identifier associated with the source cell, and the target cell's association identifier can also be described as an identifier associated with the target cell.

[0142] The information used for key change can be parameters used to derive (or deduce) the key. The information used for key change may include: next-hop chain counter (NCC) or parameters used to determine NCC, etc., which are not limited in this application embodiment.

[0143] In one implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first information, including at least one of the following:

[0144] If the switching command does not carry information for key change, the terminal determines that it does not need to perform key change or PDCP reconstruction;

[0145] When the switching command carries information for key change, the terminal determines that a key change or PDCP reconstruction needs to be performed.

[0146] In one implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on first information, including:

[0147] The terminal receives the first indication information sent by the network-side device;

[0148] The terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first instruction information.

[0149] In one implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first indication information, including at least one of the following:

[0150] If the first indication information indicates that a key change or PDCP reconstruction is not required, the terminal determines that a key change or PDCP reconstruction is not required.

[0151] When the first indication information indicates that a key change or PDCP reconstruction needs to be performed, the terminal determines that a key change or PDCP reconstruction needs to be performed.

[0152] In this implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on the association identifier of the source cell and the association identifier of the target cell. This determination can be made without additional signaling overhead, thereby reducing signaling overhead.

[0153] In this implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on whether the handover command carries information for key change. This determination can be achieved without additional signaling overhead, thus reducing signaling overhead.

[0154] In this embodiment, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first instruction information, so that the terminal can quickly determine whether a key change or PDCP reconstruction needs to be performed based on the first instruction information.

[0155] Optionally, the information used for key changes includes the next-hop link count (NCC).

[0156] In this implementation, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on whether the handover command carries an NCC (Network Control Center). This determination can be made without additional signaling overhead, thus reducing signaling overhead.

[0157] Optionally, the terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first information, including at least one of the following:

[0158] If the association identifier of the source cell matches the association identifier of the target cell, the terminal determines that it does not need to perform a key change or PDCP reconstruction.

[0159] If the association identifier of the source cell does not match the association identifier of the target cell, the terminal determines that a key change or PDCP reconstruction needs to be performed.

[0160] The mismatch between the association identifier of the source cell and the association identifier of the target cell can mean that the association identifier of the source cell and the association identifier of the target cell do not meet the preset matching conditions. For example, the mismatch between the association identifier of the source cell and the association identifier of the target cell can mean that the association identifier of the source cell and the association identifier of the target cell are not equal.

[0161] In addition, matching the association identifier of the source cell with the association identifier of the target cell can mean that the association identifier of the source cell and the association identifier of the target cell meet preset matching conditions. For example, matching the association identifier of the source cell and the association identifier of the target cell can mean that the association identifier of the source cell and the association identifier of the target cell are equal.

[0162] In this embodiment, the matching of the association identifier of the source cell and the association identifier of the target cell can indicate that the source cell and the target cell belong to the same CU or base station, and the mismatch between the association identifier of the source cell and the association identifier of the target cell can indicate that the source cell and the target cell belong to different CUs or base stations, thereby enabling a more accurate determination of whether a key change or PDCP reconstruction needs to be performed.

[0163] Optionally, the method further includes:

[0164] If the configuration information of the source cell during the handover to the first cell is saved, the terminal uses the saved configuration information to restore the configuration.

[0165] The terminal uses the saved configuration information to restore the configuration, which can be understood or replaced as the terminal restoring to the configuration used in the source primary cell or source primary cell group.

[0166] In addition, the configuration recovery in the event of cell handover failure may refer to applying the saved configuration information in the event of cell handover failure.

[0167] It should be noted that configuration recovery in the event of a cell handover failure can restore the terminal's serving cell configuration to the configuration information of the source cell.

[0168] In one embodiment, the method further includes:

[0169] The terminal selects a cell. If the cell selected by the terminal is a handover candidate cell configured for the terminal by the network-side device, the terminal performs fast recovery.

[0170] For example, after the terminal restores its configuration using the saved configuration information, the terminal performs cell selection.

[0171] In this embodiment, in the event of a cell handover failure, the terminal uses the saved configuration information to restore the configuration, which avoids the problem that the terminal cannot fall back to the source cell configuration after a handover failure. This allows the terminal to perform a fast recovery on any candidate cell, thereby increasing the probability of the terminal successfully connecting to the network.

[0172] Optionally, the configuration information of the source cell includes at least one of the following:

[0173] Configuration information of the PDCP entity of the source cell;

[0174] The configuration information of the Radio Link Control (RLC) entity of the source cell.

[0175] Optionally, the configuration information of the PDCP entity of the source cell includes at least one of the following:

[0176] The values ​​of the state variables of the PDCP entity of the source cell;

[0177] The runtime of the entity timer of the PDCP entity of the source cell;

[0178] The source cell is used to transmit security configuration information;

[0179] The source cell's PDCP entity has stored data in the transmit buffer and receive buffer;

[0180] The source cell is used to transmit compression protocol-related information;

[0181] And / or,

[0182] The configuration information of the RLC entity of the source cell includes at least one of the following:

[0183] The values ​​of the state variables of the RLC entity of the source cell;

[0184] The runtime of the entity timer of the RLC entity of the source cell;

[0185] The source cell's RLC entity has stored data in the transmit buffer and receive buffer.

[0186] The security configuration information may include security algorithms, keys, and NCC, etc. This embodiment does not limit this; any security-related configuration information used for transmission can be used as the security configuration information.

[0187] Optionally, the compression protocol-related information includes at least one of the following:

[0188] The states and variables related to the Robust header compression protocol (ROHC);

[0189] Ethernet Header Compression (EHC) protocol related states and variables;

[0190] Information about the Uplink Data Compression (UDC) protocol compression buffer.

[0191] Optionally, during the handover to the first cell, the terminal saves the configuration information of the source cell, including at least one of the following:

[0192] If the terminal needs to perform a key change or PDCP reconstruction during the handover to the first cell, the terminal saves the configuration information of the PDCP entity and the RLC entity of the source cell.

[0193] If the terminal needs to perform RLC reconstruction during the handover to the first cell, the terminal saves the configuration information of the RLC entity of the source cell.

[0194] In this embodiment, when the terminal needs to perform key change or PDCP reconstruction during the handover to the first cell, the terminal saves the configuration information of the PDCP entity and RLC entity of the source cell. Thus, in the event of a cell handover failure, the terminal can apply the saved configuration information of the PDCP entity and RLC entity of the source cell to perform configuration recovery. This avoids the problem that the terminal cannot fall back to the configuration of the source cell after a handover failure, and enables the terminal to perform fast recovery on any candidate cell, thereby increasing the probability of the terminal successfully connecting to the network.

[0195] In this embodiment, when the terminal needs to perform RLC reconstruction during the handover to the first cell, the terminal saves the configuration information of the RLC entity of the source cell. In the event of a cell handover failure, the terminal can apply the saved configuration information of the RLC entity of the source cell to perform configuration recovery. This avoids the problem that the terminal cannot fall back to the configuration of the source cell after a handover failure, and enables the terminal to perform fast recovery on any candidate cell, thereby increasing the probability of the terminal successfully connecting to the network.

[0196] Optionally, performing fast recovery includes: performing cell handover using the first configuration information.

[0197] Optionally, the first cell is a handover candidate cell configured by the network-side equipment for the terminal; and / or,

[0198] The second cell is a handover candidate cell configured by the network-side equipment for the terminal.

[0199] It should be noted that CHO only supports fast recovery to an inter-CU CHO candidate cell; LTM only supports recovery to an intra-CU LTM candidate cell after an intra-CU LTM handover failure or RLF, and does not support LTM fast recovery after L3 handover or CHO. After a handover failure or RLF, the terminal needs to fall back to the source cell's configuration before performing fast recovery. If an inter-CU handover was performed, PDCP and RLC reconstruction will be performed during the handover process. During this time, the protocol state variables and cached data packets of the PDCP and RLC entities will be reset or cleared, making it impossible to fall back to the original PDCP and RLC configuration state after a handover failure. In this case, if the target cell for fast recovery is an inter-CU cell, the terminal will perform PDCP and RLC reconstruction again. Therefore, even if it cannot fall back to the source cell configuration, it will not affect recovery to the target cell. However, if the target cell for fast recovery is an intra-CU cell, successful recovery cannot be achieved without a successful fallback. For simplicity, related technologies do not support LTM fast recovery after L3 switching or CHO switching failures in either intra-CU or inter-CU.

[0200] Related technologies do not support performing intra-CU LTM fast recovery after network-initiated L3 handover and CHO. Furthermore, since it's impossible to revert back to the source cell configuration after an inter-CU handover failure, these technologies cannot support fast recovery to an intra-CU candidate cell after an inter-CU handover failure. In this application's embodiment, in the case of intra-CU handover failure or RLF, either intra-CU or inter-CU fast recovery can be performed. In the case of inter-CU handover failure, only inter-CU fast recovery can be performed; alternatively, during inter-CU handover, the terminal saves the current PDCP and RLC configuration of the source cell. This application's embodiment solves the problems of not being able to perform intra-CU LTM fast recovery after L3 handover and CHO, and the inability to fast recover to an intra-CU candidate cell after an inter-CU handover failure.

[0201] The following examples will provide further explanation:

[0202] Example 1:

[0203] In this example, the terminal determines whether a fast recovery can be performed after a handover failure based on the first rule.

[0204] like Figure 5 As shown, the cell handover method includes the following process:

[0205] Step (1): The network-side device (or referred to as the network) configures at least one candidate cell for the terminal (such as UE) for handover, and the network-side device is configured with a fast recovery function. The fast recovery function means that after a cell handover failure or RLF occurs, if the RRC reconstruction target cell selected by the terminal is the configured candidate cell, the terminal can perform a handover instead of reconstruction.

[0206] Step (2): The terminal performs a cell handover, which fails (this can be considered the first handover). The terminal selects a cell and, according to the first rule, determines whether it can perform fast recovery (i.e., perform a handover, which can be considered the second handover) on the selected cell.

[0207] The first rule includes at least one of the following:

[0208] a. If the terminal needs to perform a key change or PDCP reconstruction when switching to the selected cell, the terminal can perform fast recovery on the selected cell; otherwise, the terminal can only perform RRC reconstruction on the selected cell and cannot perform fast recovery.

[0209] b. If the terminal does not perform key change or PDCP reconstruction during the first handover, the terminal can perform fast recovery on any candidate cell selected after the handover failure;

[0210] c. If the terminal performs a key change or PDCP reconstruction during the first handover, then fast recovery can be performed only when a key change or PDCP reconstruction is required during handover to the selected cell; alternatively, in this case, the terminal prioritizes selecting candidate cells that require a key change or PDCP reconstruction during handover when selecting cells, so as to perform fast recovery.

[0211] Optionally, the method for determining whether a key change or PDCP reconstruction is required during cell handover includes, but is not limited to, at least one of the following:

[0212] The terminal implicitly determines whether a key change or PDCP reconstruction is required during cell handover based on the first identifier configured for cell A and the second identifier configured for cell B by the network-side equipment. For example, when the first identifier of cell A and the second identifier of cell B are equal, the terminal does not perform a key change or PDCP reconstruction when performing a handover from cell A to cell B; otherwise, a key change or PDCP reconstruction is required.

[0213] The terminal determines whether a key change or PDCP reconstruction is required during handover based on whether the network-side device carries relevant information for key change in the handover command. For example, if the handover command sent by the source cell (cell A) to cell B carries the next hop link count (NCC), it is determined that a key change or PDCP reconstruction is required.

[0214] The terminal determines whether a key change or PDCP reconstruction is required during cell handover based on instructions from the network-side equipment. For example, the network-side equipment may directly instruct the terminal whether a key change or PDCP reconstruction is required when handing over from cell A to cell B.

[0215] The cell handover includes L3 HO, CHO, LTM or other cell change handover methods triggered by network-side devices.

[0216] In this example, after a handover failure, the terminal determines whether fast recovery can be performed based on the first rule, which solves the problem that fast recovery cannot be performed after L3 HO or CHO in related technologies. The terminal determines whether fast recovery can be performed on the selected cell based on whether a key change or PDCP reconstruction was performed at the time of the handover failure, thus supporting fast recovery in some scenarios and expanding the scope of fast recovery application.

[0217] Example 2:

[0218] In this example, the terminal saves the PDCP and / or RLC configuration of the source cell when performing a handover.

[0219] like Figure 6 As shown, the cell handover method includes the following process:

[0220] Step (1) is the same as step (1) in Example 1;

[0221] Step (2): The terminal saves the PDCP and / or RLC configuration of the source primary cell or source primary cell group and performs cell handover. The PDCP and / or RLC configuration of the source primary cell or source primary cell group includes at least one of the following:

[0222] The values ​​of PDCP and / or RLC entity state variables;

[0223] Runtime of PDCP and / or RLC physical timers;

[0224] Security configurations, such as security algorithms, keys, and NCC (Neural Control Center) settings;

[0225] Data already stored in the transmit and receive buffers by the PDCP and / or RLC entities;

[0226] Compression protocol-related states, variables, and buffers, such as: ROHC protocol-related states and variables; EHC protocol-related states and variables; and / or, UDC protocol compression buffer.

[0227] Optionally, the PDCP and / or RLC configuration of the source primary cell or source primary cell group is saved only when the terminal needs to perform a key change or PDCP reconstruction when switching to the target cell;

[0228] Optionally, the RLC configuration of the source primary cell or source primary cell group is saved only when the terminal needs to perform RLC reconstruction when switching to the target cell;

[0229] Step (3): If the terminal fails to switch over, restore the configuration used when it was in the source cell or source cell group, that is, restore the configuration based on the configuration saved in step (2).

[0230] Step (4): The terminal performs cell selection. If the selected cell is a candidate cell, fast recovery is performed.

[0231] In this example, when performing a handover, the terminal saves the PDCP and / or RLC configuration of the source cell for use when falling back to the source cell configuration after a handover failure. By saving the PDCP and / or RLC configuration of the source cell or source primary cell group before the handover, the problem of not being able to fall back to the source cell configuration after a handover failure is avoided, allowing the terminal to perform fast recovery on any candidate cell.

[0232] This application expands the use cases for fast recovery, supporting LTM fast recovery of intra-CU after L3 HO or CHO, and also supporting fast recovery to intra-CU candidate cells after inter-CU handover failure.

[0233] The cell handover method provided in this application can be executed by a cell handover device. This application uses the example of a cell handover device executing the cell handover method to illustrate the cell handover apparatus provided in this application.

[0234] This application provides a cell handover device. As an example, the cell handover device can be a communication device or a component within 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.

[0235] The cell handover 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.

[0236] For details, see Figure 7 When the cell handover device is a terminal or a component within a terminal, the cell handover device 200 includes:

[0237] The receiving module 201 is configured to receive first configuration information, the first configuration information including at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0238] Processing module 202 is configured to perform a first operation based on the first configuration information in the event of a radio link failure or a failure to handover to the first cell, wherein the first operation includes at least one of the following:

[0239] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0240] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0241] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0242] The first cell or the second cell is one of the candidate cells.

[0243] Optionally, the processing module is further configured to:

[0244] In the event of a radio link failure or a failure to handover to the first cell, a second operation is performed, the second operation including at least one of the following:

[0245] If the configuration information of the source cell is not saved during the handover to the first cell, then Radio Resource Control (RRC) reconstruction is performed.

[0246] If key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed.

[0247] Optionally, the processing module is further configured to:

[0248] During the handover to the first cell, the configuration information of the source cell is saved.

[0249] Optionally, the processing module is further configured to:

[0250] Release the configuration information of the source cell.

[0251] Optionally, the processing module is specifically used for:

[0252] If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and a key change or PDCP reconstruction is required during the handover process to the second cell, then cell fast recovery is performed for the second cell.

[0253] Optionally, the processing module is specifically used for:

[0254] If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and if a key change or PDCP reconstruction is not required during the handover process to the second cell, then an RRC reconstruction is performed.

[0255] Optionally, the processing module is further configured to:

[0256] In the event of a wireless link failure or failure to hand over to the first cell, if the terminal has performed a key change or PDCP reconstruction during the handover to the first cell, cell selection shall be performed according to a preset priority rule.

[0257] The preset priority rules include:

[0258] Cells that require key changes or PDCP reconstruction have a higher priority than cells that do not require key changes or PDCP reconstruction.

[0259] Optionally, the processing module is further configured to:

[0260] Determine whether a key change or PDCP reconstruction is needed based on the first piece of information;

[0261] The first information includes at least one of the following:

[0262] The association identifier of the source cell and the association identifier of the target cell;

[0263] Whether the switching command includes information for key changes;

[0264] The first indication information is used to indicate whether a key change or PDCP reconstruction needs to be performed.

[0265] Optionally, the information used for key changes includes the next-hop link count (NCC).

[0266] Optionally, the processing module is specifically used for at least one of the following:

[0267] If the association identifier of the source cell matches the association identifier of the target cell, it is determined that no key change or PDCP reconstruction is required.

[0268] If the association identifier of the source cell does not match the association identifier of the target cell, it is determined that a key change or PDCP reconstruction needs to be performed.

[0269] Optionally, the processing module is further configured to:

[0270] If the configuration information of the source cell during the handover to the first cell is saved, then the saved configuration information is used to restore the configuration.

[0271] Optionally, the configuration information of the source cell includes at least one of the following:

[0272] Configuration information of the PDCP entity of the source cell;

[0273] The configuration information of the Radio Link Control (RLC) entity of the source cell.

[0274] Optionally,

[0275] The configuration information of the PDCP entity of the source cell includes at least one of the following:

[0276] The values ​​of the state variables of the PDCP entity of the source cell;

[0277] The runtime of the entity timer of the PDCP entity of the source cell;

[0278] The source cell is used to transmit security configuration information;

[0279] The source cell's PDCP entity has stored data in the transmit buffer and receive buffer;

[0280] The source cell is used to transmit compression protocol-related information;

[0281] And / or,

[0282] The configuration information of the RLC entity of the source cell includes at least one of the following:

[0283] The values ​​of the state variables of the RLC entity of the source cell;

[0284] The runtime of the entity timer of the RLC entity of the source cell;

[0285] The source cell's RLC entity has stored data in the transmit buffer and receive buffer.

[0286] Optionally, the compression protocol-related information includes at least one of the following:

[0287] Robust header compression ROHC protocol related states and variables;

[0288] Ethernet frame header compression (EHC) protocol related states and variables;

[0289] Information about the UDC protocol compression buffer for uplink data compression.

[0290] Optionally, the processing module is specifically used for at least one of the following:

[0291] If the terminal needs to perform a key change or PDCP reconstruction during the handover to the first cell, the configuration information of the PDCP entity and the configuration information of the RLC entity of the source cell are saved.

[0292] If the terminal needs to perform RLC reconstruction during the handover to the first cell, the configuration information of the RLC entity of the source cell is saved.

[0293] Optionally, performing fast cell recovery includes: using the first configuration information to perform cell handover.

[0294] The cell handover device provided in this application embodiment can achieve... Figure 4 The various processes implemented in the method embodiments achieve the same technical effect, and will not be described again here to avoid repetition.

[0295] like Figure 8As shown, this application embodiment also provides a communication device 300, including a processor 301 and a memory 302. The memory 302 stores a program or instructions that can run on the processor 301. For example, when the communication device 300 is a terminal, when the program or instructions are executed by the processor 301, they implement the various steps of the above-described cell handover method embodiment and achieve the same technical effect.

[0296] This application embodiment 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, for example... Figure 4 The steps in the method embodiment shown are illustrated. This terminal embodiment corresponds to the above-described terminal-side method embodiment. All implementation processes and methods of the above-described method embodiments can be applied to this terminal embodiment and achieve the same technical effect. The terminal can be... Figure 7 The cell handover device shown. Specifically, Figure 9 A schematic diagram of the hardware structure of a terminal to implement an embodiment of this application.

[0297] The terminal 400 includes, but is not limited to, at least some of the following components: radio frequency unit 401, network module 402, audio output unit 403, input unit 404, sensor 405, display unit 406, user input unit 407, interface unit 408, memory 409, and processor 410.

[0298] Those skilled in the art will understand that the terminal 400 may also include a power supply (such as a battery) for supplying power to various components. The power supply may be logically connected to the processor 410 through a power management system, thereby enabling functions such as managing charging, discharging, and power consumption through the power management system. Figure 9 The terminal structure shown 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.

[0299] It should be understood that, in this embodiment, the input unit 404 may include a graphics processor 4041 and a microphone 4042. The graphics processor 4041 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 406 may include a display panel 4061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 407 includes at least one of a touch panel 4071 and other input devices 4072. The touch panel 4071 is also called a touch screen. The touch panel 4071 may include a touch detection device and a touch controller. Other input devices 4072 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.

[0300] In this embodiment, after receiving downlink data from the network-side device, the radio frequency unit 401 can transmit it to the processor 410 for processing; in addition, the radio frequency unit 401 can send uplink data to the network-side device. Typically, the radio frequency unit 401 includes, but is not limited to, antennas, amplifiers, transceivers, couplers, low-noise amplifiers, duplexers, etc.

[0301] The memory 409 can be used to store software programs or instructions, as well as various data. The memory 409 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 409 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 409 in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0302] Processor 410 may include one or more processing units; optionally, processor 410 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 410.

[0303] The radio frequency unit 401 is used to: receive first configuration information, the first configuration information including at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function;

[0304] Processor 410 is configured to: perform a first operation in the event of a radio link failure or handover to the first cell, based on the first configuration information, wherein the first operation includes at least one of the following:

[0305] If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell;

[0306] If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell.

[0307] If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell.

[0308] The first cell or the second cell is one of the candidate cells.

[0309] It is understood that the implementation process of each implementation method mentioned in this embodiment can be referred to the method embodiment. Figure 4 The relevant descriptions and the achievement of the same or corresponding technical effects will not be repeated here to avoid duplication.

[0310] 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 embodiments and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0311] 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.

[0312] 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 embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0313] 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.

[0314] 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 embodiments, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0315] 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.

[0316] 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.

[0317] 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, characterized in that, include: The terminal receives first configuration information, which includes at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function; In the event of a wireless link failure or a failure to hand over to the first cell, the terminal performs a first operation based on the first configuration information. The first operation includes at least one of the following: If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell; If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell. If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell. The first cell or the second cell is one of the candidate cells.

2. The method according to claim 1, characterized in that, Also includes: In the event of a radio link failure or a failure to hand over to the first cell, the terminal performs a second operation, which includes at least one of the following: If the configuration information of the source cell is not saved during the handover to the first cell, then Radio Resource Control (RRC) reconstruction is performed. If key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed.

3. The method according to claim 1 or 2, characterized in that, Also includes: During the process of switching to the first cell, the terminal saves the configuration information of the source cell.

4. The method according to claim 3, characterized in that, If the configuration information of the source cell during the handover to the first cell is stored, then after performing fast cell recovery for the second cell, the method further includes: The terminal releases the configuration information of the source cell.

5. The method according to any one of claims 1-4, characterized in that, If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then a fast cell recovery is performed for the second cell, including: If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and a key change or PDCP reconstruction is required during the handover process to the second cell, then cell fast recovery is performed for the second cell.

6. The method according to claim 2, characterized in that, If key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed, including: If a key change or PDCP reconstruction has been performed during the handover process to the first cell, and if a key change or PDCP reconstruction is not required during the handover process to the second cell, then an RRC reconstruction is performed.

7. The method according to any one of claims 1-6, characterized in that, The method further includes: In the event of a wireless link failure or failure to hand over to the first cell, if the terminal has performed a key change or PDCP reconstruction during the handover to the first cell, the terminal will select a cell according to a preset priority rule. The preset priority rules include: Cells that require key changes or PDCP reconstruction have a higher priority than cells that do not require key changes or PDCP reconstruction.

8. The method according to any one of claims 1-7, characterized in that, The method further includes: The terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first information. The first information includes at least one of the following: The association identifier of the source cell and the association identifier of the target cell; Whether the switching command includes information for key changes; The first indication information is used to indicate whether a key change or PDCP reconstruction needs to be performed.

9. The method according to claim 8, characterized in that, The information used for key changes includes the next-hop link count (NCC).

10. The method according to claim 8, characterized in that, The terminal determines whether a key change or PDCP reconstruction needs to be performed based on the first information, including at least one of the following: If the association identifier of the source cell matches the association identifier of the target cell, the terminal determines that it does not need to perform a key change or PDCP reconstruction. If the association identifier of the source cell does not match the association identifier of the target cell, the terminal determines that a key change or PDCP reconstruction needs to be performed.

11. The method according to any one of claims 1-10, characterized in that, The method further includes: If the configuration information of the source cell during the handover to the first cell is saved, the terminal uses the saved configuration information to restore the configuration.

12. The method according to any one of claims 1-11, characterized in that, The configuration information of the source cell includes at least one of the following: Configuration information of the PDCP entity of the source cell; The configuration information of the Radio Link Control (RLC) entity of the source cell.

13. The method according to claim 12, characterized in that, The configuration information of the PDCP entity of the source cell includes at least one of the following: The values ​​of the state variables of the PDCP entity of the source cell; The runtime of the entity timer of the PDCP entity of the source cell; The source cell is used to transmit security configuration information; The source cell's PDCP entity has stored data in the transmit buffer and receive buffer; The source cell is used to transmit compression protocol-related information; And / or, The configuration information of the RLC entity of the source cell includes at least one of the following: The values ​​of the state variables of the RLC entity of the source cell; The runtime of the entity timer of the RLC entity of the source cell; The source cell's RLC entity has stored data in the transmit buffer and receive buffer.

14. The method according to claim 13, characterized in that, The compression protocol-related information includes at least one of the following: Robust header compression ROHC protocol related states and variables; Ethernet frame header compression (EHC) protocol related states and variables; Information about the UDC protocol compression buffer for uplink data compression.

15. The method according to claim 3, characterized in that, During the handover process to the first cell, the terminal saves the configuration information of the source cell, including at least one of the following: If the terminal needs to perform a key change or PDCP reconstruction during the handover to the first cell, the terminal saves the configuration information of the PDCP entity and the RLC entity of the source cell. If the terminal needs to perform RLC reconstruction during the handover to the first cell, the terminal saves the configuration information of the RLC entity of the source cell.

16. The method according to any one of claims 1-13, characterized in that, The process of performing rapid cell recovery includes: using the first configuration information to perform cell handover.

17. A cell handover device, characterized in that, include: A receiving module is configured to receive first configuration information, the first configuration information including at least one of the following: information indicating candidate cells, and information indicating support for cell fast recovery function; The processing module is configured to perform a first operation based on the first configuration information in the event of a radio link failure or a failure to handover to the first cell, wherein the first operation includes at least one of the following: If the configuration information of the source cell during the handover to the first cell is saved, then perform fast cell recovery for the second cell; If a key change or Packet Data Convergence Protocol (PDCP) reconstruction is required during the handover to the second cell, then cell fast recovery will be performed for the second cell. If no key change or PDCP reconstruction is performed during the handover to the first cell, then fast cell recovery is performed for the second cell. The first cell or the second cell is one of the candidate cells.

18. The apparatus according to claim 17, characterized in that, The processing module is also used for: In the event of a radio link failure or a failure to handover to the first cell, a second operation is performed, the second operation including at least one of the following: If the configuration information of the source cell is not saved during the handover to the first cell, then Radio Resource Control (RRC) reconstruction is performed. If key change or PDCP reconstruction is not required during the handover to the second cell, then RRC reconstruction is performed.

19. The apparatus according to claim 17 or 18, characterized in that, The processing module is also used for: During the handover to the first cell, the configuration information of the source cell is saved.

20. The apparatus according to any one of claims 17-19, characterized in that, The processing module is also used for: In the event of a wireless link failure or failure to hand over to the first cell, if the terminal has performed a key change or PDCP reconstruction during the handover to the first cell, the cell selection shall be performed according to the preset priority rules. The preset priority rules include: Cells that require key changes or PDCP reconstruction have a higher priority than cells that do not require key changes or PDCP reconstruction.

21. The apparatus according to any one of claims 17-20, characterized in that, The processing module is also used for: Determine whether a key change or PDCP reconstruction is needed based on the first piece of information; The first information includes at least one of the following: The association identifier of the source cell and the association identifier of the target cell; Whether the switching command includes information for key changes; The first indication information is used to indicate whether a key change or PDCP reconstruction needs to be performed.

22. A terminal, characterized in that, It includes a processor and a memory, the memory storing programs or instructions that can run on the processor, the programs or instructions being executed by the processor to implement the steps of the cell handover method as described in any one of claims 1 to 16.

23. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the cell handover method as described in any one of claims 1 to 16.

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