WO2018024212A1

WO2018024212A1 - Cell handover method and apparatus

Info

Publication number: WO2018024212A1
Application number: PCT/CN2017/095644
Authority: WO
Inventors: 吴昱民
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-08-03
Filing date: 2017-08-02
Publication date: 2018-02-08
Also published as: CN107690163A

Abstract

Embodiments of the present invention provide a cell handover method and apparatus. The method comprises: receiving a configuration message for instructing to perform cell handover; keeping a connection to a source cell according to the configuration message and performing synchronization with a target cell in a case in which synchronization with the target cell is not obtained; and in a predetermined trigger condition, disconnecting the connection from the source cell and accessing the target cell. By means of the embodiments of the present invention, the problem that user equipment is disconnected from a source base station excessively early or late is resolved, that is, disconnecting a connection from the source base station excessively early may cause long data interrupt time, and disconnecting the connection from the source base station excessively late may cause more radio link failures, so that disconnection from the source base station is more accurately and appropriately, data interrupt is alleviated, radio link failures are avoided, and further, the effects of alleviating data interrupt and avoiding radio link failures are achieved.

Description

Cell switching method and device

Technical field

The present invention relates to the field of communications, and in particular, to a cell handover method and apparatus.

Background technique

The Dual Connectivity (DC) function is introduced in the Long Term Evolution (LTE) system. The DC includes two cell groups: the primary cell group (MCG) and the secondary cell. Secondary Cell Group (SCG for short). The MCG includes one primary cell PCell or additionally includes one or more secondary cells SCell (corresponding to Scell), the SCG includes one Primary Secondary Cell (PSCell) or additionally includes one or more secondary cells (Secondary Cell) , referred to as Scell). The base station that manages the MCG is called a master base station (Master eNB, abbreviated as MeNB), and the base station that manages the SCG is called a secondary base station (Secondary eNB, abbreviated as SeNB).

As shown in FIG. 1 , the bearer architecture of the SCG bearer: the user equipment (User Equipment, UE for short) has independent bearers in the MeNB and the SeNB, and the UE is independent on each evolved Node B (B Evolved Node, eNB for short). Packet Data Convergence Protocol (PDCP) entity. The uplink and downlink bearer data of the same bearer are not simultaneously transmitted to the MeNB and the SeNB for transmission. Figure 2 shows the split bearer split bearer architecture:

The connection of the UE on the MeNB may have independent bearers. The connection of the UE to the SeNB is to transmit a part of the data carried by the same Evolved Packet System (EPS) on the MeNB to the SeNB, and the Evolved Packet System (EPS) carries the PDCP. The entity is still on the MeNB, and the SeNB has an independent Radio Link Control (RLC) entity.

Introduction to the mobility process: The mobility process of the UE mainly includes the following three types: single-connection handover, SeNB/SCG change under dual connectivity, and dual-connection handover. Single connection switching: UE only and one The source base station is connected. At this time, the UE receives the handover command sent by the base station (that is, the RRCConnectionReconfiguration message includes the mobilityControlInfo information element), and the behavior of the UE mainly includes the following three phases:

Phase 1: Downlink synchronization and configuration application: Stop radio link problem detection (ie stop and/or disable timer t310/t312); start timer for handover failure detection (ie t304); stop reporting of UE auxiliary information ( Stopping the reporting of the Sidelink UEInformation message by stopping t307); performing downlink synchronization with the target primary cell (Primary Cell, Pcell for short); for a specific type of UE (such as Bandwidth reduced Low complexity (BL) UE or The UE in the coverage enhancement (CE) needs to obtain the master information block (MIB) of the target PCell; and reset the medium access control (MAC) entity of the UE; Rebuilding all the radio bearers (Radio Bearers, RBs for short), and re-establishing the RLC entities of all the RBs; deactivating the Scell; using the new UE ID (ie, the Cell Radio Network Temporary Identifier, C-RNTI) If the full configuration fullConfig is configured, this performs the corresponding fullConfig configuration process; the deletion during the execution of the switch Configure and apply the new configuration process; set the RRC ConnectionReconfigurationComplete message to complete the RRCConnectionReconfigurationComplete message, including: Radio Link Failure (RLF) information availability indication, multimedia broadcast multicast service (Multimedia Broadcast and The Multicast Service (abbreviated as MBSFN) records the measurement information available indication, records the measurement information available indication, and the connection establishment failure information available indication; sends the RRCConnectionReconfigurationComplete to the underlying entity.

Phase 2: Uplink synchronization: The MAC layer entity of the UE initiates a random access procedure to the target cell. For the contention-based random access procedure, after the UE resolves the competition (ie, receives msg4), the random access succeeds, for non-competitive After the random access procedure UE receives the feedback from the network side (that is, receives msg2), the random access succeeds.

Phase 3: Processing after successful access: After the MAC layer successfully completes the random access procedure, the UE performs the following behavior: stopping the handover failure detection (ie, stopping the timer T304). According to whether the UE obtains the system frame number (SFN) of the PCell, The steps use the corresponding configuration. Including: the channel quality indicator (CQI)/Scheduling Request (SR)/Sounding Reference Signal (SRS) configuration is not required before the SFN of the PCell is obtained. The UE knows the part of the SFN of the target PCell; after acquiring the SFN of the PCell, the configuration of the SFN of the UE target PCell needs to be known in the measurement and radio resource configuration (such as measurement interval, periodic CQI reporting, SR configuration, SRS configuration).

Report relevant auxiliary information. Including: for the UE configured with the IDC and the power preference report, the In-Device Coexistence (IDC) reporting and the UE auxiliary information (including the power preference related information) may be initiated; if the target PCell broadcasts the system information block ( The system information block (referred to as SIB15), the UE may report the MBMS interest message; if the target PCell broadcasts the SIB18, the UE may report the device-to-device (Device to Device, D2D) communication-related message content; if the target PCell broadcasts the SIB19, the UE may Report the D2D discovery related message content.

SeNB/SCG change: The UE is configured with a DC. At this time, the UE receives the SCG change command (SeNB/SCG change) sent by the primary base station (ie, the radio resource control connection reconfiguration RRCConnectionReconfiguration message includes the mobile control information secondary cell group mobilityControlInfoSCG information element). The behavior of the UE is as follows:

Phase 1: Downlink synchronization and configuration application: reset SCG MAC; rebuild PDCP entity and SCG RLC entity for SCG DRB; perform PDCP data recovery and rebuild SCG RLC entity for split DRB; change to SCG DRB for MCG DRB Rebuilding the PDCP entity and the MCG RLC entity; for the SCG SCell (except the PSCell), setting the deactivation state; updating the SCG/SeNB related key and security algorithm according to the configuration; applying the SCG's exclusive radio resource configuration; The configured SCG/Split DRB is reconfigured according to the configuration information. According to the configuration, the SCell is released from the SCG. The PSCell is added and modified according to the configuration. The SCell is added and modified according to the configuration. The underlying entity is configured. SCG DRB or split DRB SCG transmission, resume its SCG transmission; stop wireless link problem detection (ie stop and/or disable timer T313); initiate SCG change failure detection (ie start timer T307); PSCell is synchronized.

Phase 2: Uplink synchronization

Start the random access procedure for the target PSCell. The random access procedure is the same as the uplink synchronization procedure described above.

Phase 3: Processing after successful access: After the MAC layer successfully completes the random access procedure, the UE performs the following actions: Stops the SCG change failure detection (ie, stops the timer T307); and steps according to whether the UE acquires the SFN of the PSCell. Use the corresponding configuration. The method includes: before acquiring the SFN of the PSCell, adopting a part of the CQI/SR/SRS configuration that does not require the UE to know the SFN of the target PCell; after acquiring the SFN of the PSCell, adopting measurement and radio resource configuration (such as periodic CQI reporting, SR configuration) In the SRS configuration, it is necessary to know the configuration of the SFN of the UE target PCell.

Dual-connection handover: The UE is configured with a DC. At this time, the UE receives the handover command sent by the primary base station and requests to reserve the SCG of the UE (that is, the RRCConnectionReconfiguration message includes the mobilityControlInfo and the mobilityControlInfoSCG information element). The behavior of the UE is as follows:

Phase 1: Downlink synchronization and configuration application: "Phase 1: Downlink synchronization and configuration application" in the same connection handover. For the SCG part configuration, use the same phase of the SCG change "Phase 1: Downlink synchronization and configuration application" ".

Phase 2: Uplink synchronization: This uplink synchronization includes uplink synchronization with PCell ("2nd phase: uplink synchronization" in the same connection handover) and uplink synchronization with PSCell (same phase 2: uplink in the same SCG change) Synchronize"). The uplink synchronization process is performed independently for the PCell and the PSCell.

Phase 3: Processing after successful access: The "processing after successful access" includes: processing after successful PCell access ("Phase 3: processing after successful access" in the same connection switching) and Processing after successful PSCell access (same as "Process 3 after successful access" in the SCG change). The processing after the PCell is successfully accessed and the processing after the PSCell is successfully accessed are separate processing processes.

FullConfig configuration process: After receiving the information of the fullConfig configured on the network side, the behavior of the UE is as follows: clear/release the dedicated wireless configuration of the UE, except: C-RNTI of the MCG, Security configuration of the MCG, PDCP/RLC/logical channel configuration of the RB, logged measurement configuration. For the handover process (ie receiving mobilityControlInfo), all general-purpose wireless configurations are released/cleared, and the default values specified by the protocol are used for the error detection function (T310/T311/N310/N311). For the non-handover process, the default values specified by the protocol are used for the error detection function (T301/T310/T311/N310/N311). The default physical channel configuration is adopted; the default semi-persistent scheduling (SPS) configuration is adopted; the default MAC configuration is adopted; and the signaling radio bearer (Signaling Radio Bearer, SRB for short) adopts the default specified by the protocol. Configuration. If the RRC configuration includes an Evolved Packet System (EPS) bearer ID (ie, eps-BearerIdentity), the data radio bearer (DRB) corresponding to the current EPS bearer ID of the UE is released. , but keep the EPS bearer ID. If the current EPS bearer ID of the UE is not included in the Radio Resource Control (RRC) configuration, the DRB is released.

Deleting the old configuration and applying the new configuration process during the handover process: After receiving the handover command, the UE performs the following actions for deleting the old configuration and applying the new configuration: corresponding to each entity of the UE according to the universal and dedicated radio resource configuration Configuration; update the security key and security algorithm of the UE according to the security configuration; perform the addition/modification/deletion of the SCell according to the configuration; perform the reconfiguration of the SCG according to the SCG configuration; adopt the configured SIB1; perform the measurement configuration process related to the handover Perform measurement according to the measurement configuration in the handover command; delete the unavailable measurement ID; delete the proximity indication measurement related to the Closed Subscriber Group (CSG); apply other types of configurations according to the configuration in the handover command, including : proximity indication measurement configuration, obtaining location information configuration, IDC reporting configuration, power preference reporting configuration; applying D2D related configuration according to the configuration in the switching command; applying a wireless local area network (Wireless Local Area Network, WLAN for short) according to the configuration in the switching command ) data offload related configuration; release LTE and WLA LTE-WLAN aggregation (LTE-WLAN Aggregation, abbreviated as LWA) and LTE and WLAN are LTE-WLAN Radio Level Integration with IPsec Tunnel (LTE-WLAN) LWIP) related configuration; apply WLAN service transfer according to the configuration in the handover command Related configuration; apply LWA and LWIP related configuration according to the configuration in the switch command.

After the handover-related command is received, the UE performs the following actions on the configuration related to the handover: the periodic measurement reporting is deleted; for the inter-frequency handover, the measurement target is the handover target frequency, and the source is associated with the source. The measurement ID of the frequency point is re-associated to the target frequency point, and the measurement ID associated with the target frequency point is re-associated to the source frequency point. For other cases, delete the measurement related to the source frequency point; delete all measurement reporting configurations; stop the periodic reporting timer and the system information acquisition timer (ie, T321); release the measurement interval;

A method of switching between the source and target cell connections. As shown in FIG. 3, it is a flow chart of signaling handover: since the current LTE system adopts a handover method in which a source cell is disconnected first, and then a connection is established in a target cell (ie, break-before-make, which is established after the interruption first) ). The transmission and reception of business data will be interrupted. Therefore, the 3GPP discussion group provides a new scheme for maintaining the UE's connection between the source cell and the target cell (ie, make-before-break, first set up and then interrupt). It is used to reduce the UE side handover interruption delay. That is, the UE remains connected to the source base station after receiving the handover command, and disconnects from the source base station before or after accessing the target base station. Further, the network side may not trigger the random access procedure of the UE during the handover process, and configure the uplink transmission resource of the target cell (such as the Physical Uplink Shared Channel (PUSCH) for the UE in the handover command. The resource is transmitted so that the UE can directly send the uplink data in the target cell directly on the uplink.

The problem that the user equipment disconnects from the source base station too early or too late, that is, disconnecting the source base station too early will lead to more data interruption time, and too late disconnection from the source base station will lead to more The wireless link fails, and no effective solution has been proposed in the related art.

Summary of the invention

The embodiment of the present invention provides a cell handover method and apparatus, so as to at least solve the problem that the user equipment disconnects from the source base station too early or too late in the related art, that is, disconnecting the source base station too early may result in more Data interruption time, disconnecting the source base station too late will cause more wireless links to fail.

According to an embodiment of the present invention, a cell handover method is provided, including: receiving And a configuration message indicating that the cell handover is performed; maintaining a connection with the source cell according to the configuration message, and synchronizing with the target cell if the synchronization with the target cell is not obtained; and disconnecting the source cell with a predetermined trigger condition Connected and accesses the target cell.

According to another embodiment of the present invention, a cell switching apparatus is provided, including: a receiving module, configured to receive a configuration message for indicating cell handover; and a processing module configured to maintain a source cell according to the configuration message Connecting and synchronizing with the target cell without obtaining synchronization with the target cell; the disconnecting module is configured to disconnect the source cell and access the target cell under a predetermined trigger condition.

According to still another embodiment of the present invention, a storage medium is also provided. The storage medium is arranged to store program code for performing the above steps.

With the embodiment of the present invention, the user equipment UE disconnects from the source cell and accesses the target cell under the predetermined trigger condition when the user equipment UE is connected to the source cell, so that the user equipment and the source base station can be resolved. The problem of opening too early or too late, that is, disconnecting the source base station too early will lead to more data interruption time, and too late disconnection from the source base station will cause more wireless link failures, reaching more Accurate and reasonable interruption with the source base station, reducing the implementation of data interruption, and avoiding the failure of the wireless link.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is an architectural diagram of a SCG bearer in the related art;

2 is an architectural diagram of a Split bearer in the related art;

3 is a flow chart of handover signaling in the related art;

4 is a block diagram showing the hardware structure of a mobile terminal in a cell handover method according to an embodiment of the present invention;

Figure 5 is a flow chart of a method in accordance with an embodiment of the present invention;

6 is a schematic diagram of a single connection handover according to an embodiment of the present invention;

7 is a flow diagram of dual connectivity switching in accordance with an embodiment of the present invention;

FIG. 8 is a structural block diagram of a cell switching apparatus according to an embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It is to be understood that the terms "first", "second" and the like in the specification and claims of the present invention are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

The method embodiments provided by the embodiments of the present application may be implemented in a mobile terminal, a computer terminal, or the like. 4 is a block diagram of a hardware structure of a mobile terminal according to a cell handover method according to an embodiment of the present invention. As shown in FIG. 4, mobile terminal 40 may include one or more (only one of which is shown in FIG. 4) processor 402 (processor 402 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA. ), a memory 404 configured to store data, and a transmission device 406 configured as a communication function. It will be understood by those skilled in the art that the structure shown in FIG. 4 is merely illustrative and does not limit the structure of the above electronic device. For example, the mobile terminal 40 may also include more or fewer components than those shown in FIG. 4, or have a different configuration than that shown in FIG.

The memory 404 can be configured as a software program and a module for storing application software, such as a program instruction/module corresponding to the cell switching method in the embodiment of the present invention, and the processor 402 executes each by executing a software program and a module stored in the memory 404. A functional application and data processing, that is, the above method is implemented. Memory 404 can include high speed random access memory and can also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid state memory. In some examples, memory 404 can further include memory remotely located relative to processor 402, which can be connected to mobile terminal 40 over a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Transmission device 406 is arranged to receive or transmit data via a network. The above network The body instance may include a wireless network provided by a communication provider of the mobile terminal 40. In one example, the transmission device 406 includes a Network Interface Controller (NIC) that can be connected to other network devices through a base station to communicate with the Internet. In one example, the transmission device 406 can be a Radio Frequency (RF) module configured to communicate with the Internet wirelessly.

In this embodiment, a cell switching method is performed on the mobile terminal, and FIG. 5 is a flowchart of a method according to an embodiment of the present invention. As shown in FIG. 5, the process includes the following steps:

Step S502, receiving a configuration message for indicating that cell handover is performed;

Step S504, maintaining a connection with the source cell according to the configuration message, and synchronizing with the target cell without obtaining synchronization with the target cell;

Step S506, disconnecting the source cell and accessing the target cell under a predetermined trigger condition.

Through the above steps, since the user equipment UE disconnects from the source cell and accesses the target cell under the predetermined trigger condition while maintaining the connection with the source cell, it can be resolved that the user equipment disconnects from the source base station too early or The problem of too late, that is, disconnecting the source base station too early will lead to more data interruption time, and too late disconnection from the source base station will lead to more wireless link failures, achieving more accurate and reasonable. Interruption with the source base station reduces the implementation of data interruption and also avoids the occurrence of radio link failure.

Optionally, the execution body of the foregoing steps may be a terminal, but is not limited thereto.

In an optional embodiment, the predetermined triggering condition may include at least one of: completing downlink synchronization with the target cell; completing a k-th subframe of a protocol agreed upon by downlink synchronization with the target cell, determining that the source is to be disconnected a connection of a cell, where the above k is a value agreed upon by the protocol; determining, in the kth subframe before the first transmittable uplink physical random access channel PRACH resource of the target cell, disconnecting the source cell, where k is a value agreed upon by the protocol; the kth subframe before the first transmittable uplink transmission resource of the target cell determines that the connection of the source cell is to be disconnected, wherein k is a value agreed upon by the protocol; disconnection and source Connection of the cell group MCG.

In an optional embodiment, when the configuration message includes a handover command for indicating cell handover, maintaining a connection with the source cell according to the handover command and performing downlink synchronization with the target cell includes at least one of the following operations. Starting the handover failure detection process; stopping the reporting of the auxiliary information, wherein the auxiliary information includes at least one of: device-to-device D2D auxiliary information, device-type coexistence IDC auxiliary information, power preference information, multimedia broadcast multicast service MBMS interest information And performing downlink synchronization with the target primary cell; acquiring the primary information block MIB of the target primary cell; acquiring the random access configuration of the target primary cell; and acquiring the configuration of the uplink sending resource of the target primary cell. In this embodiment, the handover failure detection process is started, which may be a timer that triggers the handover failure detection, that is, t304. The reporting of the stop assistance information includes: stopping the reporting of the Siledlink UEInformation message by triggering t307, stopping the reporting of the IDC auxiliary information; stopping the power The reporting of the preference information; the reporting of the MBMS interest information is stopped; the MIB of the target Pcell needs to be acquired for a specific type of UE (such as a BL UE or a UE in CE); and the configuration of the uplink transmission resource of the target primary cell is acquired, where the uplink transmission resource It can be a PUSCH resource. The configuration of the random access configuration and the downlink sending resource may be carried in the configuration message.

In an optional embodiment, when the configuration message includes a handover command for indicating a cell handover, disconnecting the connection with the source cell includes at least one of: stopping wireless link problem detection; resetting the user equipment. a media access control MAC entity of the UE; re-establishing a packet data convergence protocol PDCP entity of all radio bearers RB; reestablishing radio link control RLC entities of all radio bearers RB; deactivating the secondary cell; adopting a new terminal identifier; When fullConfig is configured, the corresponding full configuration configuration process is executed; the old configuration and the application new configuration process are performed during the handover process; the RRCConnectionReconfigurationComplete message is set to complete the radio resource control connection reconfiguration; and the RRCConnectionReconfigurationComplete message is sent to the radio resource control connection reconfiguration. The underlying entity. In this embodiment, stopping the radio link problem detection, that is, stopping and/or not starting the timer t310/t312; adopting a new terminal identifier (UE ID), that is, a Cell Radio Network Temporary Identifier (C-RNIT); The related content in the RRCConnectionReconfigurationComplete message includes: an RLF information available indication, an MBSFN recording measurement information available indication, and a recording measurement information available indication. Connection establishment failure information available indication.

In an optional embodiment, when the foregoing configuration message includes a handover command for indicating a cell handover, after disconnecting the connection with the source cell, the method further includes: initiating a random access procedure to the target primary cell. And/or, initiating uplink data transmission according to the configured uplink transmission resource of the target primary cell.

In an optional embodiment, after determining to successfully access the target primary cell, the method further includes at least one of: stopping handover failure detection; determining whether to acquire the system frame number SFN of the target cell, and determining the result according to the determination Use corresponding measurement and / or radio resource configuration; report auxiliary information. In this embodiment, the handover failure detection is stopped, that is, the timer t304 is stopped; the system frame number SFN of the target cell is obtained, and after the SFN of the PCell is acquired, measurement and radio resource configuration (such as measurement interval, periodic CQI reporting) are adopted. In the SR configuration, the SRS configuration, the configuration of the SFN of the UE target PCell needs to be known; the reporting of the auxiliary information includes: for the UE configured with the IDC and the power preference report, the IDC reporting and the UE auxiliary information (including the power preference related information) may be initiated. If the target PCell broadcasts the SIB15, the UE may report the MBMS interest message; if the target PCell broadcasts the SIB18, the UE may report the D2D communication related message content; if the target PCell broadcasts the SIB19, the UE may report the D2D discovery related message content.

In an optional embodiment, determining that the condition for successfully accessing the target primary cell includes at least one of: a random access with the target primary cell succeeding; and starting to send the first uplink data on the target primary cell; Receiving a first successful receiving indication from the network side, where the first successful receiving indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary cell; in the target primary cell The kth subframe before the first transmittable uplink transmission resource determines that the connection of the source cell is to be disconnected, wherein the above k is a value agreed upon by the protocol; the handover completion message is started to be sent on the target primary cell; and the network side is received. The second successful receiving indication, wherein the second successful receiving indication is used to indicate that the network side successfully receives the handover complete message sent on the target primary cell; and the first transmittable complete message in the target primary cell The kth subframe before the frame determines that the connection of the source cell is to be disconnected; and receives an uplink resource release indication from the network side; Successful access to an indication from the network side.

In an optional embodiment, when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, maintaining the connection with the source SCG cell according to the SCG change command and performing the foregoing SCG cell with the target SCG cell. The synchronization includes at least one of: acquiring a random access configuration of the target primary secondary cell; acquiring a configuration of the uplink transmission resource of the target primary secondary cell; performing downlink synchronization with the target primary secondary cell; and starting the SCG change failure detection process. In this embodiment, the SCG change failure detection process is started, that is, the timer t307 is started; and the configuration of the uplink transmission resource of the target primary secondary cell is obtained, where the uplink transmission resource may be a PUSCH resource; and the startup SCG change failure detection process may be started. Timer t307.

In an optional embodiment, when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, disconnecting the connection with the source cell includes at least one of: resetting the media connection of the SCG. Incoming control MAC entity; for the data radio bearer DRB of the SCG, rebuilding the packet data convergence protocol PDCP entity and the radio link control RLC entity of the SCG; for the segmented DRB, performing the PDCP data recovery and reestablishing the radio link control RLC entity of the SCG; The data radio bearer DRB of the primary cell group MCG is configured to be changed to the DRB of the SCG, and the radio link control RLC entity of the PDCP entity and the MCG is reconstructed; for the secondary cell SCell of the SCG, the deactivated state is set; the key of the SCG is updated and Security algorithm; apply the SCG's dedicated radio resource configuration; reconfigure according to the SCG or split data radio bearer Split DRB information that the user equipment UE has configured; perform the release of the secondary cell SCell of the SCG; perform the addition and modification of the primary secondary cell PSCell Configuring the underlying entity; for the suspended radio SCB of the SCG or the SCG transmission of the split data radio bearer Split DRB, SCG repeat the above transmission; SCG stop detection of a radio link problem. In the present embodiment, the detection of stopping the wireless link problem may be to stop and/or not start the timer t313.

In an optional embodiment, when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, after disconnecting the connection with the source cell and accessing the target cell, the foregoing method further The method includes: initiating a random access procedure to the target primary secondary cell; and/or transmitting uplink data according to the configured uplink sending resource of the target primary secondary cell.

In an optional embodiment, after determining to successfully access the target primary secondary cell, the method further includes at least one of: stopping SCG change failure detection; determining whether to obtain The system frame number SFN of the target primary secondary cell is used, and corresponding measurement and/or radio resource configuration is adopted according to the determination result. In this embodiment, stopping the SCG change failure detection, that is, stopping the timer t307; determining whether to acquire the system frame number SFN of the target primary secondary cell, and adopting the corresponding measurement and/or radio resource configuration according to the determination result includes: acquiring the PSCell Before the SFN, the part of the CQI/SR/SRS configuration that does not require the UE to know the SFN of the target PCell is used. After the SFN of the PSCell is acquired, the measurement and radio resource configuration (such as periodic CQI reporting, SR configuration, SRS configuration) are used. It is necessary to know the configuration of the SFN of the UE target PCell.

In an optional embodiment, the condition for determining to successfully access the target primary secondary cell includes at least one of: a random access with the target primary secondary cell succeeding; and starting to send the first one on the target primary secondary cell Uplink data; receiving a third successful reception indication from the network side, where the third successful reception indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary secondary cell; An uplink resource release indication from the network side; receiving a successful access indication from the network side; determining, in the kth subframe before the first transmittable uplink resource of the target primary secondary cell, to disconnect the source cell, where The above k is the value agreed by the agreement.

The following describes the specific embodiments:

Specific Embodiment 1: Single-connection switching to maintain source connection:

The behavior of a single-connected UE after receiving a handover command is shown in Figure 6.

Step 1: The UE maintains a connection with the source base station cell (including the PCell and the SCell) and synchronizes with the target cell. The UE needs to perform the following actions in the process:

Initiating handover failure detection (ie, starting timer t304);

Stopping the reporting of the UE auxiliary information includes: stopping the reporting of the D2D auxiliary information (ie, the Sidelink UEInformation message) by stopping t307; stopping the reporting of the IDC auxiliary information (ie, the InDeviceCoexIndication message); stopping the reporting of the power preference information (ie, the UEAssistanceInformation message); and stopping the MBMS interest message ( That is, the MBMSInterestIndication message is reported;

Downlink synchronization with the target PCell;

For a specific type of UE (such as BL UE or UE in CE), it is required to acquire the MIB of the target PCell;

Obtain a random access configuration of the target cell PCell in the configuration message.

Step 2: After satisfying the connection of the release source cell, the UE starts to release the source cell and starts to access the target cell.

The conditions for releasing the connection of the source cell include (the next k value can be "0"):

Successfully completing downlink synchronization with the target cell PCell;

The kth subframe after successfully completing the downlink synchronization with the target cell PCell determines that the connection of the source cell is to be disconnected, where k is a protocol-scheduled value;

Determining that the connection of the source cell is to be disconnected in the kth subframe before the first transmittable uplink PRACH resource of the target cell PCell, where k is a value agreed upon by the protocol;

The behavior of releasing the source cell connection includes:

Stop wireless link problem detection (ie stop and/or disable timer t310/t312).

Reset the MAC entity of the UE;

Rebuilding PDCP entities of all RBs;

Rebuilding RLC entities of all RBs;

Deactivate the Scell;

Adopt a new UE ID (ie C-RNTI);

If fullConfig is configured, this performs the corresponding fullConfig configuration process;

Perform the process of deleting the old configuration and applying the new configuration process during the switching process;

Setting related content in the RRCConnectionReconfigurationComplete message, including: an RLF information available indication, an MBSFN record measurement information available indication, a record measurement information available indication, and a connection establishment failure information available indication;

Send RRCConnectionReconfigurationComplete to the underlying entity.

Step 3: The UE initiates a random access procedure to the target cell PCell.

Step 4: After the random access of the UE is successful, the UE performs the following actions:

Stop switching failure detection (ie stop timer T304);

According to whether the UE acquires the SFN of the PCell, the corresponding configuration is adopted in steps. The method includes: before acquiring the SFN of the PCell, adopting a part of the CQI/SR/SRS configuration that does not require the UE to know the SFN of the target PCell; after acquiring the SFN of the PCell, adopting measurement and radio resource configuration (such as measurement interval, periodic CQI reporting) , SR configuration, SRS configuration) need to know the configuration of the SFN of the UE target PCell;

Report relevant auxiliary information. Including: for the UE configured with the IDC and the power preference report, the IDC (ie, the InDeviceCoexIndication message) report and the UE auxiliary information (including the power preference related information) (ie, the UEAssistanceInformation message) may be initiated. If the target PCell broadcasts the SIB15, the UE may report the MBMS. The interest message (ie, the MBMSInterestIndication message); if the target PCell broadcasts the SIB18, the UE may report the D2D communication related message content (ie, the Sidelink UEInformation message); if the target PCell broadcasts the SIB19, the UE may report the D2D discovery related message content (ie, the Sidelink UEInformation message).

Specific Embodiment 2: Maintaining SCG/SeNB changes in source connections.

The specific process stages of this specific embodiment are the same as those of the specific embodiment 1.

Step 1: After receiving the SCG change command, the UE maintains the connection with the source SCG cell and synchronizes with the target SCG cell, and the UE performs the following actions:

Obtaining a random access configuration of the target cell PSCell in the configuration message;

Downlink synchronization with the target PSCell;

The detection of the failure of the SCG change is initiated (ie, the timer T307 is started).

Step 2: The UE disconnects from the source SCG cell and accesses the target cell PSCell on the premise that the UE is disconnected from the source SCG.

The conditions for disconnecting from the source SCG include:

Successfully completing downlink synchronization with the target cell PSCell;

The kth subframe after successfully completing the downlink synchronization with the target cell PSCell determines that the connection of the source cell is to be disconnected, where k is a protocol-scheduled value;

The kth subframe before the first transmittable uplink PRACH resource of the target cell PSCell determines to disconnect the source cell, where k is a protocol-agreed value;

The behavior of the UE disconnecting from the source cell includes:

Reset the SCG MAC;

Rebuilding the PDCP entity and the SCG RLC entity for the SCG DRB;

For split DRB, performing PDCP data recovery and reconstructing the SCG RLC entity;

For the MCG DRB to be configured to be changed to the SCG DRB, the PDCP entity and the MCG RLC entity are reconstructed;

For SCG SCell (except PSCell), set to deactivated state;

Update the SCG/SeNB related key and security algorithm according to the configuration;

Apply SCG's proprietary radio resource configuration;

Reconfiguring the SCG/Split DRB configured by the current UE according to the configuration information;

Perform SCELL release of the SCG according to the configuration;

According to the configuration, perform the addition and modification of the PSCell;

Perform SCell addition and modification of the SCG according to the configuration;

Configuring the underlying entity;

Resume the SCG transmission for the SCG transmission of the suspended SCG DRB or split DRB;

Stop wireless link problem detection (ie stop and/or disable timer T313).

Step 3: The UE initiates a random access procedure to the target cell PSCell.

Step 4: After the random access procedure initiated by the UE to the target cell PSCell is successful, the UE performs The following behavior:

Stop SCG change failure detection (ie stop timer T307).

According to whether the UE acquires the SFN of the PSCell, the corresponding configuration is adopted in steps. The method includes: before acquiring the SFN of the PSCell, adopting a part of the CQI/SR/SRS configuration that does not require the UE to know the SFN of the target PCell; after acquiring the SFN of the PSCell, adopting measurement and radio resource configuration (such as periodic CQI reporting, SR configuration) In the SRS configuration, it is necessary to know the configuration of the SFN of the UE target PCell.

Specific Embodiment 3: Maintaining dual connectivity switching of source connections.

FIG. 7 is a flowchart of dual-connection handover according to a specific embodiment of the present invention. Step 1: The UE receives a handover command and a SCG change command, and both network-side commands indicate that the connection with the source cell needs to be maintained. Then the UE performs the synchronization process with the target PCell, that is, the target PSCell, in parallel. The behavior after the UE receives the handover command (as shown in FIG. 6 ) is the same as the step 1 in the specific embodiment 1. After the UE receives the SCG change command, the behavior of the UE is the same as step 1 in the specific embodiment 2 .

Step 2.1: The behavior of the UE disconnecting from the source MCG and accessing the target PCell is the same as step 2 in the specific embodiment 1.

Step 2.2: The behavior of the UE disconnecting from the source SCG and accessing the target PSCell is the same as step 2 in Embodiment 2. The difference is that the trigger condition for the UE to disconnect from the source SCG cell additionally includes “the UE disconnects from the source MCG cell”.

Step 3.1: Same as step 3 in the specific embodiment 1.

Step 3.2: Same as Step 3 in Specific Example 2.

Step 4.1: Same as step 4 in Specific Example 1.

Step 4.2: Same as step 4 in Specific Example 2.

Specific Embodiment 4: Single connection switching without triggering a random access procedure

The processing flow phase of the UE of this specific embodiment is the same as that of the specific embodiment 1. The difference is that the UE is connected. The received handover command indicates that the random access procedure is not initiated in the target cell PCell. Instead, the uplink transmission PUSCH resource of the target cell PCell is configured in the handover command, and is used for the UE to send uplink data.

Step 1: Same as Step 1 of Specific Example 1. The difference is that the UE does not need to "acquire the random access configuration of the target cell PCell in the configuration message.", instead, the UE needs to "acquire the configuration of the uplink transmission resource of the allocated target cell PCell in the configuration message, where the uplink The sending resource can be a PUSCH resource."

Step 2: Same as Step 2 of Specific Example 1. The difference is that the condition for the UE to release the source cell connection does not include "determining the connection to disconnect the source cell in the kth subframe before the first transmittable uplink PRACH resource of the target cell PCell, where k is the agreed value of the protocol" The condition of the substitution is that "the kth subframe before the first transmittable uplink transmission resource of the target cell PCell determines the connection to disconnect the source cell, where k is the value agreed upon by the protocol".

Step 3: The UE initiates uplink data transmission according to the configured uplink sending resource of the target cell PCell.

Step 4: Same as Step 4 of Specific Example 1. The difference is that the conditions for successful access between the UE and the target cell PCell are:

The UE starts to send the first uplink data in the target cell PCell;

Receiving, by the UE, a successful reception indication from the network side of the first uplink data sent by the target cell PCell;

The UE determines, in the kth subframe before the first transmittable uplink transmission resource of the target cell PCell, that the connection of the source cell is to be disconnected, where k is a value agreed by the protocol;

The UE starts to send a handover complete message in the target cell PCell;

Receiving, by the UE, a successful reception indication from the network side of the handover complete message sent by the target cell PCell;

The UE determines to disconnect the source cell in the kth subframe before the first transmittable handover complete message subframe of the target cell PCell, where k is a protocol-scheduled value;

Receiving, by the UE, an uplink resource release indication on the network side;

The UE receives a successful access indication on the network side.

Embodiment 5: SCG/SeNB change that does not trigger a random access procedure

The processing flow phase of the UE of this specific embodiment is the same as that of the specific embodiment 2. The difference is that the SCG change command received by the UE indicates that the random access procedure is not initiated in the target cell PSCell. Instead, the uplink transmission PUSCH resource of the target cell PSCell is configured in the SCG change command, and is used for the UE to send uplink data.

Step 1: Same as Step 1 of Specific Example 2. The difference is that the UE does not need to "acquire the random access configuration of the target cell PSCell in the configuration message", instead, the UE needs to "acquire the configuration of the uplink transmission resource of the allocated target cell PSCell in the configuration message, where the uplink transmission Resources can be PUSCH resources."

Step 2: Same as Step 2 of Specific Example 2. The difference is that the condition for the UE to release the source cell connection does not include "determining the connection to disconnect the source cell in the kth subframe before the first transmittable uplink PRACH resource of the target cell PSCell, where k is the agreed value of the protocol" The condition of the substitution is that "the kth subframe before the first transmittable uplink transmission resource of the target cell PSCell determines the connection to disconnect the source cell, where k is the value agreed upon by the protocol".

Step 3: The UE initiates uplink data transmission according to the configured uplink sending resource of the target cell PSCell.

Step 4: Same as Step 4 of Specific Example 2. The difference is that the conditions for successful access between the UE and the target cell PSCell are:

The UE starts to send the first uplink data in the target cell PSCell;

Receiving, by the UE, a successful reception indication from the network side of the first uplink data sent by the target cell PSCell;

The UE receives a successful access indication on the network side;

The UE determines to disconnect the source cell in the kth subframe before the first transmittable uplink transmission resource of the target cell PSCell, where k is a protocol agreed value;

Embodiment 6: Dual connection handover that does not trigger a random access procedure.

Step 1: The UE receives the handover command and the SCG change command, and both network side commands indicate that the connection with the source cell needs to be maintained. Then the UE performs the synchronization process with the target PCell, that is, the target PSCell, in parallel. The behavior of the UE after receiving the handover command (as shown in FIG. 6 ) is the same as the step 1 in the specific embodiment 4, and the behavior of the UE after receiving the SCG change command is the same as step 1 in the specific embodiment 5.

Step 2.1: The behavior of the UE disconnecting from the source MCG and accessing the target PCell is the same as step 2 in the specific embodiment 4.

Step 2.2: The behavior of the UE disconnecting from the source SCG and accessing the target PSCell is the same as step 2 in the specific embodiment 5. The difference is that the trigger condition for the UE to disconnect from the source SCG cell additionally includes “the UE disconnects from the source MCG cell”.

Step 3.1: Same as Step 3 in Specific Example 4.

Step 3.2: Same as step 3 in the specific embodiment 5.

Step 4.1: Same as step 4 in Specific Example 4.

Step 4.2: Same as step 4 in Specific Example 5.

Specific Embodiment 7: Single connection handover that does not trigger a random access procedure and maintains a source connection. Same as Embodiment 1.

Embodiment 8: SCG/SeNB changes that do not trigger a random access procedure and maintain source connections. Same as Embodiment 2.

Embodiment 9: Dual connection handover that does not trigger a random access procedure and maintains a source connection. Same as Embodiment 3.

Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware, but in many cases, the former is A better implementation. Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a storage medium (such as ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a cell phone, a computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

In the embodiment, a cell switching device is also provided, which is used to implement the foregoing embodiments and preferred embodiments, and details are not described herein. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

FIG. 8 is a structural block diagram of a cell switching apparatus according to an embodiment of the present invention. As shown in FIG. 8, the apparatus includes: a receiving module 82, a processing module 84, and a disconnecting module 86. The following describes the device:

The receiving module 82 is configured to receive a configuration message for indicating cell handover, and the processing module 84 is connected to the receiving module 82, configured to maintain a connection with the source cell according to the configuration message, and not obtain synchronization with the target cell. The synchronization with the target cell is performed; the disconnecting module 86 is connected to the processing module 84, and is configured to disconnect the source cell and access the target cell under a predetermined trigger condition.

In an optional embodiment, the predetermined triggering condition includes at least one of: completing downlink synchronization with the target cell; completing a k-th subframe of a protocol agreed upon by downlink synchronization with the target cell, determining to disconnect the source cell Connection, where k is a value agreed by the protocol; the first uplink physical random access channel PRACH that can be sent in the target cell The kth subframe before the source determines that the connection of the source cell is to be disconnected, wherein the above k is a value agreed upon by the protocol; the kth subframe before the first transmittable uplink transmission resource of the target cell determines that the source cell is to be disconnected Connection, where k is a value agreed upon by the protocol; disconnection from the source primary cell group MCG.

In an optional embodiment, the processing module 84 may perform the following steps: maintaining the connection with the source cell according to the foregoing switching command, and performing downlink synchronization with the target cell, including: starting a handover failure detection process; and stopping reporting of the auxiliary information, The auxiliary information includes at least one of the following: device-to-device D2D auxiliary information, device-type coexistence IDC auxiliary information, power preference information, multimedia broadcast multicast service MBMS interest information, downlink synchronization with a target primary cell, and acquisition of a target primary cell. The primary information block MIB; acquires the random access configuration of the target primary cell; and acquires the configuration of the uplink transmission resource of the target primary cell.

In an optional embodiment, the disconnecting module 86 may disconnect the foregoing source cell by at least one of: stopping the wireless link problem detection; and resetting the media access control MAC entity of the user equipment UE; Rebuilding the packet data convergence protocol PDCP entity of all radio bearers RB; reestablishing the radio link control RLC entity of all radio bearers RB; deactivating the secondary cell; adopting a new terminal identifier; performing full configuration when full configuration fullConfig is configured The fullConfig configuration process; performing the deletion process to delete the old configuration and applying the new configuration process; setting the radio resource control connection reconfiguration to complete the RRCConnectionReconfigurationComplete message; and transmitting the radio resource control connection reconfiguration complete RRCConnectionReconfigurationComplete message to the underlying entity.

In an optional embodiment, the foregoing apparatus further includes: a first initiating module and/or a first sending module, and the device is described below:

a first initiating module, configured to initiate a random access procedure to the target primary cell after disconnecting the source cell and accessing the target cell;

The first sending module is configured to initiate uplink data transmission according to the configured uplink sending resource of the target primary cell after disconnecting the source cell and accessing the target cell.

In an optional embodiment, the foregoing apparatus may further include at least one of the following: the first stop The module, the first judging module, and the reporting module are described below:

The first stopping module is configured to stop the handover failure detection after determining that the target primary cell is successfully accessed; the first determining module is configured to determine, after determining that the target primary cell is successfully accessed, whether to acquire the system frame of the target cell No. SFN, and corresponding measurement and/or radio resource configuration is adopted according to the judgment result; the reporting module is configured to report the auxiliary information after determining that the target primary cell is successfully accessed.

In an optional embodiment, the foregoing determining, by the first determining module, that the condition for successfully accessing the target primary cell includes at least one of the following: a random access with the target primary cell is successful; and the sending is started on the target primary cell. An uplink data received from the network side, wherein the first successful reception indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary cell; The kth subframe before the first transmittable uplink transmission resource of the target primary cell determines that the connection of the source cell is to be disconnected, where k is a value agreed upon by the protocol; and the handover completion message is started to be sent on the target primary cell; Receiving a second successful reception indication from the network side, where the second successful reception indication is used to indicate that the network side successfully receives the handover complete message sent on the target primary cell; the first one in the target primary cell may be The kth subframe before the handover completion message subframe is determined to disconnect the source cell; the upper side receives the network side Resource release indication; successfully received access instruction from the network side.

In an optional embodiment, the processing module 84 may maintain the connection with the source cell and perform downlink synchronization with the target cell by using at least one of the following manners: when the configuration message includes the indication for performing the secondary cell group SCG. When the SCG change command is changed, the random access configuration of the target primary secondary cell is acquired according to the SCG change command; and when the configuration message includes an SCG change command for indicating the change of the secondary cell group SCG, the SCG change command is obtained according to the SCG change command. Configuration of uplink transmission resources of the target primary secondary cell; downlink synchronization with the target primary secondary cell; initiation of SCG change failure detection processing.

In an optional embodiment, the processing module 84 may disconnect the foregoing source cell by using at least one of the following manners: when the configuration message includes indicating to perform a secondary cell group When the SCG change command of the SCG is changed, the media access control MAC entity of the SCG is reset; when the configuration message includes an SCG change command for indicating the change of the secondary cell group SCG, the data radio bearer DRB of the SCG is reconstructed. a packet data convergence protocol PDCP entity and a radio link control RLC entity of the SCG; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, performing PDCP data recovery and reconstructing the SCG for the divided DRB The radio link controls the RLC entity; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, the data radio bearer DRB for the primary cell group MCG is configured to be changed to the DRB of the SCG, and the PDCP entity is reconstructed. The wireless link control RLC entity of the MCG; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, set to a deactivated state for the secondary cell SCell of the SCG; update the SCG key and security Sexual algorithm; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, applying the dedicated radio resource of the SCG When the configuration message includes the SCG change command for indicating the change of the secondary cell group SCG, the configuration is re-configured according to the SCG or the split data radio bearer SplitDRB information that the user equipment UE has configured; when the configuration message includes When the SCG change command of the change of the secondary cell group SCG is performed, the release of the secondary cell SCell of the SCG is performed; the addition and modification of the primary secondary cell PSCell are performed; and the configuration message includes the SCG change for indicating the change of the secondary cell group SCG. When the command is configured, the underlying entity is configured; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, the SCG transmission of the data radio bearer DRB of the suspended SCG or the split data radio bearer Split DRB, The SCG transmission is resumed; when the configuration message includes an SCG change command for indicating a change of the secondary cell group SCG, the detection of the SCG radio link problem is stopped.

In an optional embodiment, the foregoing apparatus further includes: a second initiating module and/or a second sending module, and the device is described below:

a second initiating module, configured to: after disconnecting from the source cell and accessing the target cell, initiate a random access procedure to the target primary secondary cell; and/or, the second sending module is configured to be disconnected After the connection of the source cell and the access to the target cell, the uplink data transmission is initiated according to the configured uplink transmission resource of the target primary secondary cell.

In an optional embodiment, the foregoing apparatus further includes at least one of the following: a second stopping module and a second determining module, where the device is described below:

a second stopping module, configured to stop the SCG change failure detection after determining that the target primary secondary cell is successfully accessed; and the second determining module is configured to determine whether to acquire the target primary after determining to successfully access the target primary secondary cell The system frame number SFN of the secondary cell, and corresponding measurement and/or radio resource configuration is adopted according to the judgment result.

In an optional embodiment, the condition for successfully accessing the target primary secondary cell may be determined by at least one of the following conditions: random access with the target primary secondary cell is successful; and sending is started on the target primary secondary cell An uplink data received from the network side, wherein the third successful reception indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary secondary cell; Receiving an uplink resource release indication from the network side; receiving a successful access indication from the network side; determining, in the kth subframe before the first transmittable uplink resource of the target primary secondary cell, disconnecting the source cell, Where k is the value agreed upon by the protocol.

It should be noted that each of the above modules may be implemented by software or hardware. For the latter, the foregoing may be implemented by, but not limited to, the foregoing modules are all located in the same processor; or, the above modules are in any combination. The forms are located in different processors.

Embodiments of the present invention also provide a storage medium. Optionally, in the embodiment, the above storage medium may be configured to store program code for performing the above steps.

Optionally, in the embodiment, the foregoing storage medium may include, but is not limited to, a USB flash drive, a Read-Only Memory (ROM), and a Random Access Memory (RAM). A variety of media that can store program code, such as a hard disk, a disk, or an optical disk.

Optionally, in this embodiment, the processor performs the above steps according to the stored program code in the storage medium.

For example, the specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the optional embodiments, and details are not described herein again.

It will be apparent to those skilled in the art that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

As described above, the cell handover method and apparatus provided by the embodiments of the present invention have the following beneficial effects: the problem that the user equipment disconnects from the source base station too early or too late, that is, the connection with the source base station is disconnected prematurely. Lead to more data interruption time, too late disconnection with the source base station will lead to more wireless link failure, achieve more accurate and reasonable interruption with the source base station, reduce the realization of data interruption, and avoid the wireless chain Road failure occurred. In turn, the effect of reducing data interruption and avoiding the failure of the wireless link is achieved.

Claims

A cell handover method includes:

Receiving a configuration message indicating that the cell handover is performed;

Maintaining a connection with the source cell according to the configuration message and synchronizing with the target cell without obtaining synchronization with the target cell;

Disconnecting from the source cell and accessing the target cell under predetermined trigger conditions.
The method of claim 1 wherein said predetermined triggering condition comprises at least one of:

Performing downlink synchronization with the target cell;

The kth subframe of the protocol agreed upon by the downlink synchronization with the target cell determines that the connection of the source cell is to be disconnected, where k is a value agreed upon by the protocol;

The kth subframe before the first transmittable uplink random access channel resource of the target cell determines that the connection of the source cell is to be disconnected, where k is a value agreed by the protocol;

The kth subframe before the first transmittable uplink transmission resource of the target cell determines that the connection of the source cell is to be disconnected, where k is a value agreed by the protocol;

Disconnect from the source primary cell group.
The method according to claim 1, wherein when the configuration message includes a handover command for indicating cell handover, maintaining a connection with the source cell according to the handover command and performing downlink synchronization with the target cell Includes at least one of the following:

Initiating a handover failure detection process;

And stopping the reporting of the auxiliary information, where the auxiliary information includes at least one of the following: device-to-device auxiliary information, device-type coexistence auxiliary information, power preference information, and multimedia broadcast multicast service interest information;

Perform downlink synchronization with the target primary cell;

Obtaining a main information block of the target primary cell;

Obtaining a random access configuration of the target primary cell;

Obtain the configuration of the uplink sending resource of the target primary cell.
The method of claim 1, wherein when the configuration message includes a handover command for indicating cell handover, disconnecting from the source cell includes at least one of:

Stop wireless link problem detection;

Reset the media access control entity of the user equipment;

Rebuilding all packet-aggregation protocol entities of the radio bearer;

Rebuilding all radio bearer radio link control entities;

Deactivate the secondary cell;

Adopt a new terminal identifier;

When the full configuration is configured, the corresponding full configuration configuration process is executed.

Perform the process of deleting the old configuration and applying the new configuration process during the switching process;

Set the radio resource control connection reconfiguration complete message;

The RRC connection reconfiguration complete message is sent to the underlying entity.
The method according to claim 1, wherein when the configuration message includes a handover command for indicating a cell handover, after disconnecting the connection with the source cell, the method further includes at least one of the following:

Initiating a random access procedure to the target primary cell;

The uplink data transmission is initiated according to the configured uplink sending resource of the target primary cell.
The method of claim 5, wherein after determining to successfully access the target primary cell, the method further comprises at least one of the following:

Stop switching failure detection;

Determining whether to obtain the system frame number of the target cell, and adopting corresponding measurement according to the determination result, or adopting a corresponding radio resource configuration, or adopting corresponding measurement and radio resource configuration;

Report auxiliary information.
The method of claim 6, wherein the condition for determining successful access to the target primary cell comprises at least one of the following:

The random access with the target primary cell is successful;

Starting to send the first uplink data on the target primary cell;

Receiving a first successful receiving indication from the network side, where the first successful receiving indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary cell;

The kth subframe before the first transmittable uplink transmission resource of the target primary cell determines that the connection of the source cell is to be disconnected, where k is a value agreed by the protocol;

Starting to send a handover complete message on the target primary cell;

Receiving a second successful reception indication from the network side, where the second successful reception indication is used to indicate that the network side successfully receives a handover complete message sent on the target primary cell;

Determining that the connection of the source cell is to be disconnected in the kth subframe before the first transmittable handover complete message subframe of the target primary cell;

Receiving an uplink resource release indication from the network side;

Received a successful access indication from the network side.
The method according to claim 1, wherein when the configuration message includes a secondary cell group change command for indicating a change of the secondary cell group, maintaining the primary secondary cell group cell according to the secondary cell group change command Connect and connect with the target secondary cell group cell Synchronization includes at least one of the following actions:

Obtaining a random access configuration of the target primary secondary cell;

Obtaining a configuration of an uplink sending resource of the target primary secondary cell;

Downlink synchronization with the target primary secondary cell;

The secondary cell group change failure detection process is started.
The method according to claim 1, wherein when the configuration message includes a secondary cell group change command for indicating a change of the secondary cell group, disconnecting the connection with the source secondary cell group cell includes at least one of the following:

Resetting the media access control entity of the secondary cell group;

Reestablishing a packet data convergence protocol entity and a radio link control entity of the secondary cell group for the data radio bearer of the secondary cell group;

For the split radio bearer, performing packet data convergence protocol data recovery and reestablishing the radio link control entity of the secondary cell group;

And the radio bearer of the primary cell group is configured to be changed into the radio bearer of the secondary cell group, and the packet data convergence protocol entity and the radio link control entity of the primary cell group are reconstructed;

For the secondary cell of the secondary cell group, set to a deactivated state;

Updating the secret key and security algorithm of the secondary cell group;

Apply the dedicated radio resource configuration of the secondary cell group;

Reconfiguring according to the secondary cell group or the split data radio bearer information that has been configured by the user equipment;

Performing the release of the secondary cell of the secondary cell group;

Performing addition and modification of the primary secondary cell;

Configuring the underlying entity;

Restoring the secondary cell group transmission for the data radio bearer of the suspended secondary cell group or the secondary cell group transmission of the divided data radio bearer;

The detection of the wireless link problem of the secondary cell group is stopped.
The method according to claim 1, wherein when the configuration message includes a secondary cell group change command for indicating a change of the secondary cell group, after disconnecting the connection with the source cell, the method further Includes at least one of the following:

Initiating a random access procedure to the target primary secondary cell;

The uplink data transmission is initiated according to the configured uplink sending resource of the target primary secondary cell.
The method of claim 10, wherein after determining to successfully access the target primary secondary cell, the method further comprises at least one of the following:

Stop the secondary cell group change failure detection;

Determining whether to obtain the system frame number of the target primary secondary cell, and adopting corresponding measurement according to the determination result, or adopting a corresponding radio resource configuration, or adopting corresponding measurement and radio resource configuration.
The method of claim 11, wherein the condition for determining successful access to the target primary secondary cell comprises at least one of the following:

The random access with the target primary secondary cell is successful;

Starting to send the first uplink data on the target primary secondary cell;

Receiving a third successful receiving indication from the network side, where the third successful receiving indication is used to indicate that the network side successfully receives the first uplink data sent on the target primary secondary cell;

Receiving an uplink resource release indication from the network side;

Received a successful access indication from the network side;

The kth subframe before the first transmittable uplink resource of the target primary secondary cell determines the connection to disconnect the source cell, where k is a protocol-available value.
A cell switching device includes:

a receiving module, configured to receive a configuration message used to indicate that a cell handover is performed;

a processing module, configured to maintain a connection with the source cell according to the configuration message, and synchronize with the target cell if the synchronization with the target cell is not obtained;

And disconnecting the module, configured to disconnect the source cell and access the target cell under a predetermined trigger condition.
The apparatus of claim 13, wherein the predetermined trigger condition comprises at least one of:

Performing downlink synchronization with the target cell;

Completing a k-th subframe of a protocol agreed upon by downlink synchronization with the target cell, where k is a value agreed upon by the protocol;

a kth subframe before the first transmittable uplink random access channel resource of the target cell, where the k is a protocol-assigned value;

a kth subframe before the first transmittable uplink transmission resource of the target cell, where the k is a value agreed by the protocol;

Disconnect from the source primary cell group.
A storage medium, the storage medium comprising a stored program, wherein the program is executed to perform the method of any one of claims 1 to 12.