CN114451062A

CN114451062A - Communication method and device

Info

Publication number: CN114451062A
Application number: CN201980100641.5A
Authority: CN
Inventors: 王瑞; 孙慧明; 胡星星
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2022-05-06
Also published as: WO2021062677A1

Abstract

The application provides a communication method and a communication device, which are applied to the technical field of wireless communication. The communication method comprises the following steps: when the first radio link fails, the RLC bearer is controlled by the first radio link to switch the main path of the separated bearer to a second RLC bearer; and switching the main path to the first RLC bearer when the RRC connection is reestablished. According to the method and the device, after the terminal fails in MCG quick recovery, the terminal automatically or in an MN-assisted mode switches the main path to MCG RLC bearing, so that the terminal side configuration is aligned with the base station side configuration, and therefore the RRC message of the SRB1 can be separated in the RRC reestablishment process normally to be received and sent, the RRC reestablishment process is completed, the normal double-connection communication of the terminal is maintained, and the communication quality is improved.

Description

Communication method and device

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a communication method and apparatus.

Background

In Dual Connectivity (DC), a terminal may simultaneously acquire a communication service from a master node (master MN) and a Secondary Node (SN). The bearer established between the terminal and the MN is referred to as a Master Cell Group (MCG) bearer, and the bearer established between the terminal and the SN is referred to as a Secondary Cell Group (SCG) bearer. When the terminal detects that the MCG bearer can not carry out data transmission, the MCG link fails, and the terminal can send MCG failure information to the MN through the SCG bearer, so that MCG quick recovery is carried out. In order to be able to send an MCG failure message to the MN through the SCG bearer, a terminal not configured with repetition (duplicate) transmission needs to switch a primary path (primary path) from the MCG RLC bearer to the SCG RLC bearer.

However, the MCG fast recovery procedure also fails, and the terminal needs to re-establish a Radio Resource Control (RRC) connection. Since the main path has been switched to SCG RLC bearer before, if the terminal reestablishes the RRC connection, it may cause failure in RRC reestablishment.

Disclosure of Invention

The embodiment of the application provides a communication method and a communication device, which are used for completing an RRC reestablishment process when an MCG rapid recovery fails.

In a first aspect, the present application provides a communication method for a terminal supporting dual connectivity, where the terminal has a first radio link with a first base station and a second radio link with a second base station, and the terminal is configured to separate bearers, the method includes:

when the first radio link fails, switching the main path of the separated bearer from a first Radio Link Control (RLC) bearer to a second RLC bearer, wherein the separated bearer comprises the first RLC bearer and the second RLC bearer, the first RLC bearer corresponds to the first radio link, and the second RLC bearer corresponds to the second radio link; and when the RRC connection is reestablished, switching the main path to the first RLC bearer.

According to the method and the device, after the terminal fails in MCG quick recovery, the terminal automatically or in an MN-assisted mode switches the main path to MCG RLC bearing, so that the terminal side configuration is aligned with the base station side configuration, and therefore the RRC message of the SRB1 can be separated in the RRC reestablishment process normally to be received and sent, the RRC reestablishment process is completed, the normal double-connection communication of the terminal is maintained, and the communication quality is improved.

In another possible implementation, the switching the primary path to the first RLC bearer while RRC connection reestablishment is performed includes:

judging whether the main path of the separated load is the second RLC load; and when the main path is the second RLC bearing, switching the main path to the first RLC bearing.

For different terminals, when detecting the MCG link failure, some terminals perform MCG fast recovery and then perform RRC connection reestablishment, and some terminals perform RRC connection reestablishment directly. Therefore, for different terminals, when RRC connection reestablishment is performed, it is necessary to detect whether the current main path is MCG RLC bearer or SCG RLC bearer.

In another possible implementation, the method further comprises: and when the RRC reconfiguration message or the RRC release message of the first base station is not received within the preset time, determining that the first radio link fails to recover, and reestablishing the RRC connection. Therefore, the terminal is prevented from waiting for the MN to perform MCG fast recovery indefinitely, and the reaction time of the terminal is shortened.

In another possible implementation, the method further comprises: in the process of recovering from the failure of the first radio link, when the second radio link fails, determining that the recovery of the first radio link fails, and performing the RRC connection reestablishment. Therefore, the RRC connection is reestablished without waiting for overtime, thereby further shortening the reaction time of the terminal.

In another possible implementation, the method further comprises: sending the first link recovery failure cause value to the first base station, where the first link recovery failure cause value is used to trigger the first base station to generate indication information indicating that the main path is switched to the first RLC bearer; and receiving the indication information from the first base station, and switching the main path to the first RLC bearing.

If the terminal cannot actively switch the main path to the MCG RLC bearer, a new re-establishment cause value of "MCG fast recovery failure" may be added in the re-establishment request message initiating the RRC connection to the first base station, so that the first base station configures, for the terminal, the indication information for separating the main path of the SRB1 into the MCG RLC bearer, to assist the terminal in switching the main path.

In a second aspect, the present application provides a communication method, performed by a first base station, comprising:

transmitting first request information to a second base station; the first request information is used for requesting whether the second base station supports the first base station to perform first radio link failure recovery through a Signaling Radio Bearer (SRB) between the second base station and a terminal, wherein the first radio link is a radio link between the first base station and the terminal; receiving first feedback information from the second base station in response to the first request information; and indicating the terminal to recover the first radio link failure through the SRB according to the first feedback information.

In the embodiment of the application, when the MN requests the SN to support MCG fast recovery through SRB3, after inquiring whether the SN supports MCG fast recovery, the MN requests the terminal to configure a bearer for MCG fast recovery through SRB3, thereby avoiding the problem in the prior art that service interruption time is too long due to the fact that the SN does not support MCG fast recovery when the MN requests the terminal to configure a bearer for MCG fast recovery through SRB 3.

In another possible implementation, before sending the first request message to the second base station, the method includes: sending query information to the second base station, wherein the query information is used for querying whether the second base station supports the SRB; receiving response information from the second base station; the response information is used for indicating that the second base station supports the SRB.

In the embodiment of the present application, when the MN requests the SN to support MCG fast recovery through SRB3, before querying whether the SN supports MCG fast recovery, it is further required to query whether the SN supports SRB3, so as to avoid the problem of too long service interruption time.

In another possible implementation, the method further comprises: sending second request information to the second base station; the second request information is used for requesting whether to release the resource for the first radio link failure recovery through the SRB; receiving second feedback information from the second base station in response to the second request information; requesting the terminal to release the configuration of the first radio link failure recovery through the SRB in the second base station.

According to the embodiment of the application, after the MN completes the flow of MCG fast recovery through the SRB3, the previous configuration of the SN and the terminal is cancelled, so that the resource occupation of the SN and the terminal is avoided.

In a third aspect, the present application provides a communication method, performed by a second base station, including:

receiving first request information sent by a first base station, where the first request information is used to request whether the second base station supports the first base station to perform first radio link failure recovery through a Signaling Radio Bearer (SRB) between the second base station and a terminal, and the first radio link is a radio link between the first base station and the terminal; and sending first feedback information to the first base station, wherein the first feedback information is used for triggering the first base station to indicate the terminal to recover the first radio link failure through the SRB.

In another possible implementation, the receiving the first request information sent by the first base station includes: receiving query information sent by the first base station, where the query information is used to query whether the second base station supports the SRB; sending response information to the first base station; the response information is used for indicating that the second base station supports the SRB.

In another possible implementation, the method further comprises: receiving second request information sent by the first base station; the second request information is used for requesting whether to release the resource for the first radio link failure recovery through the SRB; sending second feedback information to the first base station; the second feedback information is used to trigger the first base station to request the terminal to release the configuration for performing the first radio link failure recovery through the SRB in the second base station.

In a fourth aspect, an embodiment of the present application provides a communication apparatus having a function of implementing a behavior of a terminal in the communication method shown in the first aspect above. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more units or means (means) corresponding to the functions described above.

In one possible design, the apparatus includes a processor configured to enable the apparatus to perform the corresponding functions of the terminal in the communication method shown above. The apparatus may also include a memory, which may be coupled to the processor, that retains program instructions and data necessary for the apparatus. Optionally, the apparatus further comprises a transceiver configured to support communication between the apparatus and a network element such as a relay device, an access network device, or the like. Wherein the transceiver may be a separate receiver, a separate transmitter, or a transceiver integrating transceiving functions.

In one possible implementation, the communication device may be a terminal or a component usable for a terminal, such as a chip or a system of chips or a circuit.

In a fifth aspect, an embodiment of the present application provides a communication apparatus, where the apparatus has a function of implementing a behavior of a first base station in the resource allocation method for recovering bearer recovery shown in the second aspect above. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more units or means (means) corresponding to the above functions.

In one possible design, the apparatus includes a processor configured to enable the apparatus to perform corresponding functions of the access network device in the communication method shown above. The apparatus may also include a memory, which may be coupled to the processor, that retains program instructions and data necessary for the apparatus.

In one possible implementation, the resource allocation means for recovering bearer recovery may be the first base station, or a component available to the base station, such as a chip or a system of chips or a circuit.

Optionally, the apparatus further includes a transceiver, which may be configured to support communication between the access network device and the terminal, and send information or instructions related to the communication method to the terminal. The transceiver may be a stand-alone receiver, a stand-alone transmitter, or a transceiver integrating transceiving functionality.

In a sixth aspect, an embodiment of the present application provides a communication system, including a first base station serving as a primary node, and a second base station serving as a secondary node. Optionally, the communication system may further include a terminal, and the terminal may access the first base station and the second base station simultaneously.

According to a seventh aspect, an embodiment of the present application provides a computer-readable storage medium, having stored therein instructions, which, when executed on a computer, cause the computer to perform the method of any one of the above aspects.

In an eighth aspect, embodiments of the present application provide a computer program product comprising instructions that, when executed on a computer, cause the computer to perform the method of any of the above aspects.

Drawings

The drawings that accompany the detailed description can be briefly described as follows.

Fig. 1 is a schematic diagram of a communication system 100 according to an embodiment of the present application;

fig. 2(a) is a schematic diagram of a dual connection scenario provided in an embodiment of the present application;

fig. 2(b) is a schematic diagram of a dual connection scenario provided in an embodiment of the present application;

fig. 2(c) is a schematic diagram of an LTE-NR dual connectivity scenario provided in an embodiment of the present application;

fig. 2(d) is a schematic diagram of an LTE-NR dual connectivity scenario provided in an embodiment of the present application;

fig. 3(a) is a schematic diagram of a first dual-connection wireless protocol architecture according to an embodiment of the present application;

fig. 3(b) is a schematic diagram of a second dual-connection wireless protocol architecture provided in the embodiment of the present application;

fig. 4 is a flowchart of a communication method according to an embodiment of the present application;

fig. 5 is a flowchart of a communication method according to an embodiment of the present application;

fig. 6 is a flowchart of a communication method according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a terminal according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a base station according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

Fig. 1 is a schematic diagram of a communication system 100 according to an embodiment of the present application. As shown in fig. 1, terminal 130 supports DC, and access network device 110 and access network device 120 together provide data transmission service for terminal 130, where access network device 110 is an MN and access network device 110 is an SN. The MN110 and a Core Network (CN) 140 have a control plane connection or a user plane connection; the SN120 may or may not have a user plane connection with the core network 140, where the user plane connection is represented by S1-U and the control plane connection is represented by S1-C. It is understood that the user plane connection of the MN110 to the core network 140 and the user plane connection of the SN120 to the core network 140 may exist simultaneously or only one of them may exist. When the SN120 and the core network 140 do not have a user plane connection, data of the terminal 130 may be shunted to the SN120 by the MN110 in a Packet Data Convergence Protocol (PDCP) layer. When the MN110 and the core network 140 do not have a user plane connection, data of the terminal 130 can be shunted to the MN110 by the SN120 at the PDCP layer. The above MN may also be referred to as a primary base station or primary access network device, and the SN may also be referred to as a secondary base station or secondary access network device.

In the present application, terminal 130 may be any of a variety of devices that provide voice and/or data connectivity to a user, such as a handheld device having wireless connection capability or a processing device connected to a wireless modem. A terminal may communicate with a core network via an access network, such as a Radio Access Network (RAN), and may exchange voice and/or data with the RAN. The terminal may refer to a User Equipment (UE), a wireless terminal, a mobile terminal, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile), a remote station (remote station), an Access Point (AP), a remote terminal (remote terminal), an access terminal (access terminal), a user terminal (user terminal), a user agent (user agent), a user equipment (user device), or the like. For example, mobile phones (or so-called "cellular" phones), computers with mobile terminals, portable, pocket, hand-held, computer-included or vehicle-mounted mobile devices, smart wearable devices, and the like may be included. For example, devices such as Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), smartbands, smartwatches, and the like. Also included are constrained devices, such as devices that consume less power, or devices that have limited storage capabilities, or devices that have limited computing capabilities, etc. Examples of information sensing devices include bar codes, Radio Frequency Identification (RFID), sensors, Global Positioning Systems (GPS), laser scanners, and the like. Furthermore, the terminal 130 may also be a drone device. In the embodiments of the present application, a chip applied to the above-described apparatus may also be referred to as a terminal.

The communication system in the present application may be a Long Term Evolution (LTE) wireless communication system, or a fifth generation (5G) mobile communication system such as a New Radio (NR) system, or other Next Generation (NG) communication systems, and the present application is not limited thereto.

In this application, the

access network devices

110 and 120 may be base stations defined by the third generation partnership project (3 GPP). For example, the base station device may be a base station device in an LTE system, that is, an evolved NodeB (eNB/eNodeB); the network side device may also be an access network side device in the NR system, and includes a gNB, a transmission point (TRP), and the like. The Access network device 110 or the Access network device 120 may be composed of a Centralized Unit (CU) and a Distributed Unit (DU), where the CU may also be referred to as a Control Unit (CU), a Protocol layer of the base station may be split by using a structure of CU-DU, functions of a part of the Protocol layer are centrally controlled by the CU, functions of the remaining part or all of the Protocol layer are distributed in the DU, and the DU is centrally controlled by the CU, for example, a Radio Resource Control (RRC), a Service Data Adaptation Protocol (SDAP), and a Packet Data Convergence Protocol (Packet Convergence Protocol, PDCP) layer may be deployed in the CU, and the remaining Radio Link Control (RLC), a medium Access Control (Access, MAC) layer, and a Physical layer (Physical Control) are deployed in the Physical Control. The CU and DU are connected via an F1 interface. The CU represents the gNB connected to the core network via the NG interface. Alternatively, the CU may also adopt a structure in which a control plane (control plane) entity and a User Plane (UP) entity are separated, and one control plane entity manages a plurality of user plane entities. In one example, a gNB can have one gNB-CU-CP, multiple gNB-CU-UP and multiple gNB-DUs. One gNB-CU-CP interfaces with multiple gNB-CU-UP via E1, one gNB-CU-CP may interface with multiple gNB-DUs via F1-C, and one gNB-DU may interface with multiple gNB-CU-UP via F1-U.

In addition, when the Core Network of the eNB accessing the NR is referred to as a Next Generation Core (NGC) or a 5G Core Network (5 GC), the LTE eNB may also be referred to as an LTE eNB. Specifically, the LTE eNB is an LTE base station device that evolves on the basis of the LTE eNB, and may be directly connected to the 5G CN, and the LTE eNB also belongs to a base station device in the NR. The access network device 101 or the access network device 102 may also be a Wireless Terminal (WT), such as an Access Point (AP) or an Access Controller (AC), or other network devices having a capability of communicating with a terminal and a core network, such as a relay device, a vehicle-mounted device, an intelligent wearable device, and the like.

The Dual Connectivity may be implemented between access network devices of the same standard, as shown in fig. 2(a), which is a schematic diagram of an NR-NR Dual Connectivity (NR-DC) network of a 5G core network. In the NR-based networking scenario, both the MN110 and the SN120 are NR gnbs, and an Xn interface exists between the MN110 and the SN 120. An NG interface exists between the MN110 and the NGC, at least a control plane connection exists, and a user plane connection also exists; there is an NG-U interface between the SNs 120 and 5GC, i.e. there can only be a user plane connection. The NGC may include functional entities such as a core access and mobility management function (AMF) network element and a User Plane Function (UPF) network element.

Dual connectivity may also be implemented between heterogeneous access network devices, which may be referred to as Multi-RAT DC (MR-DC), where MN and SN employ different Radio Access Technologies (RATs). A multi-RAT DC (MR-DC) architecture supports multiple bearer types, different types of bearers can be distinguished by using MN or SN as an anchor point through a Packet Data Convergence Protocol (PDCP) layer, and bearer types can be switched. For example, dual connectivity can be realized in a scenario of LTE and NR joint networking, so that a terminal can obtain radio resources from LTE and NR air interfaces at the same time to perform data transmission, thereby obtaining a gain of a transmission rate. LTE and NR dual connectivity may include the following three architectures, which are described below in conjunction with fig. 2(b), fig. 2(c), and fig. 2(d), respectively.

Please refer to fig. 2(b), which is a schematic diagram of an LTE-NR Dual Connectivity (E-UTRA-NR Dual Connectivity, EN-DC) network. As shown in fig. 2(b), LTE eNB is MN and NR gbb is SN. There is an X2 interface between LTE eNB and NR gbb. An S1 interface exists between an LTE eNB and an Evolved Packet Core (EPC) of the LTE system, and there is at least control plane connection and may also be user plane connection; an S1-U interface exists between the NR gbb and the EPC, i.e. only a user plane connection is possible. As can be seen, in the scenario shown in fig. 2(b), the LTE eNB is used as an anchor point, and the LTE eNB accesses the core network of LTE.

Please refer to fig. 2(c), which is a schematic diagram of an NR-LTE Dual Connectivity (NE-DC) network. The difference from fig. 2(b) is that, taking NR gNB as an anchor point, and the NR gNB accesses to NGC, where NR gNB is used as MN, and there is an NG interface between NR gNB and NGC, and a control plane connection and a user plane connection can be established for the terminal; the LTE eNB is used as an SN, an NG-U interface exists between the LTE eNB and the NGC, and user plane connection is only established for the terminal.

Please refer to fig. 2(d), which is a schematic diagram of a LTE-NR Dual Connectivity (nen-DC) network as a 5G core network. . The LTE eNB is used as an anchor point as in fig. 2(b), and the difference is that the LTE eNB accesses the NGC. That is, the LTE eNB serves as a MN, and an NG interface exists between the LTE eNB and the NGC, which can establish a control plane connection and a user plane connection for the terminal; and the NR gNB is used as the SN, and has an NG-U interface with the NGC, and only establishes user plane connection for the terminal.

In the above four scenarios, the SN and the core network may not establish a user plane connection, but transmit Data through the MN, for example, in a downlink direction, Data of the terminal first arrives at the MN, and the MN shunts the Data of the terminal to the SN on the PDCP layer, where the form of the shunted Data is, for example, a PDCP Protocol Data Unit (PDU). When there is no user plane connection between the MN and the core network and the SN is connected to the core network by the user plane, the data of the terminal may also be transmitted from the core network to the SN, and shunted to the MN by the SN, which is not described in detail.

In dual connectivity, the DRB and SRB established by the terminal and the access network side may be provided by the MN or the SN independently, or may be provided by both the MN and the SN. The bearer provided by the MN is called MCG bearer, wherein the MCG comprises at least one MN-managed cell for providing air interface transmission resources for the terminal; the bearer provided by the SN is referred to as an SCG bearer, where the SCG includes at least one SN-managed cell for providing air interface transmission resources for the terminal. Further, the bearer provided by both the MN and the SN is called a split bearer (split bearer).

When there is only one cell in the MCG, the cell is a primary cell (PCell) of the terminal. When there is only one cell in the SCG, the cell is a primary secondary cell (PSCell) of the terminal. The PCell and the PSCell may be collectively referred to as a special cell (scell). When there are multiple cells in each of the MCG or SCG, the cells other than the SpCell may be referred to as secondary cells (scells). At this time, the SCell and the SpCell in each cell group perform Carrier Aggregation (CA) to provide transmission resources for the terminal together. The PSCell belongs to a cell of the SCG, and the terminal is instructed to perform random access or initial PUSCH transmission. An SCell is a cell operating on a secondary carrier, and may be configured to provide additional radio resources once an RRC connection is established.

Fig. 3(a) and fig. 3(b) are schematic diagrams of wireless protocol architectures of dual connectivity provided by an embodiment of the present application, respectively. As shown in fig. 3(a) and 3(b), when the bearer is provided only by the MN, i.e., the data flow is only from the core network to the MN, the bearer is an MCG bearer (bearer). When the bearer is provided by the SN only, i.e. the data flow is from the core network to the SN only, the bearer is an SCG bearer. When the bearer is provided by both MN and SN, i.e. the data flow is split at either MN or SN, the bearer is a split bearer (MCG split bearer), for the sake of distinction, split at MN may be referred to as MCG split bearer (as in fig. 3(a)), and split at SN may be referred to as SCG split bearer (as in fig. 3 (b)). As can be seen from fig. 3(a) and 3(b), each bearer type has corresponding PDCP layer processing and RLC layer processing, for example, SCG bearer/SCG split bearer corresponds to SCG RLC bearer and SN terminated PDCP bearer.

Depending on whether the PDCP entity is established in the MN or SN, the bearers in the DC can be further classified into several types, including: MCG bearers terminated at MN (MN terminated MCG bearer), SCG bearers terminated at MN (MN terminated SCG bearer), split bearers terminated at MN (MN terminated split bearer), MCG bearers terminated at SN (SN terminated MCG bearer), SCG bearers terminated at SN (SN terminated SCG bearer), and split bearers terminated at SN (SN terminated split bearer), wherein for bearers terminated at MN, a PDCP entity is established at MN, and the user plane connection with the core network is terminated at MN, i.e. with MN as anchor point (anchor); for the bearer terminated at the SN, the PDCP entity is established at the SN, and the user plane connection with the core network is terminated at the SN, i.e., the SN is used as an anchor point. It can be understood that whether the bearer is terminated at the MN or the SN indicates that data transmission with the core network is performed through the MN or the SN, and as for an air interface transmission resource, the air interface transmission resource is provided by the MCG or the SCG, for example, if an MN terminated SCG bearer is used, uplink data sent by the terminal is processed through the MAC layer and the RLC layer of the SN, and then all forwarded to the PDCP layer of the MN for processing, and sent to the core network device through an interface between the MN and the core network; correspondingly, the downlink data sent by the core network is processed by the PDCP layer of the MN, then is completely transferred to the RLC layer and the MAC layer of the SN for further processing, and is sent to the terminal through the SCG. If the MN terminated split bearer is adopted, one part of uplink data sent by the terminal is sent to the MN through the MCG, the other part of the uplink data is sent to the SN through the SCG, and the two parts of data are converged to the PDCP layer of the MN for processing and are sent to the core network equipment through an interface between the MN and the core network; correspondingly, after the downlink data sent by the core network is processed by the PDCP layer of the MN, a part of the data is transferred to the SN and is sent to the terminal by the SCG, and the rest of the data is still sent to the terminal by the MN through the MCG.

And in the control plane information interaction process between the terminal and the base station, the terminal and the base station transmit signaling information through the SRB. Taking fig. 3(a) as an example, for an MN, the MN sends signaling information to the terminal through the SRB 1. When the RLC layer below the PDCP layer of the MN is separated, one part transmits signaling information to the terminal through the RLC layer of the MN, and the other part transmits signaling information to the terminal through the RLC layer of the SN, which is referred to as a separated SRB 1. For SNs, the SN sends signaling information to the terminal through SRB3, SRB3 is a signaling radio bearer established directly between the terminal and the SN.

When the terminal sends uplink data to the MN through the separation SRB1, if the terminal configuration repeat (duplicate) transmission is activated, the terminal may send the uplink data to the PDCP layer of the MN directly through an MCG bearer, or send the uplink data to the PDCP layer of the MN through an SCG bearer; if the terminal configuration repetition (duplicate) transmission is not activated, the terminal can only select one bearer from the MCG bearer and the SCG bearer for data transmission, and at this time, the bearer is referred to as a primary path. The main path is configured by the base station side, and the main path is used for the terminal to send an uplink data packet.

Fig. 4 is a flowchart of a communication method according to an embodiment of the present application. As shown in fig. 4, in order to solve the above problem, the present embodiment proposes a communication method, which may be performed by a terminal, or may be performed by a device for a terminal, such as a chip or a system-on-chip, the terminal supporting DC communication. The method comprises the following steps:

step S401, when the first radio link fails, the primary path of the split bearer is switched from the first radio link control RLC bearer to the second RLC bearer.

For convenience of the following description of the scheme, in the embodiment of the present application, the main path is taken as MCG bearer as an example. The first wireless link refers to an MCG link between the terminal and the MN, and the bearer for data transmission through the MCG link is an MCG bearer; the second wireless link refers to an SCG link between the terminal and the SN, and the bearer for data transmission through the SCG link is an SCG bearer.

The split bearer may be a split SRB1 bearer. The separate bearer comprises two RLC bearers, wherein the first RLC belongs to MCG, and the first RLC bearer is a bearer for data transmission through the first RLC and can also be represented as MCG RLC bearer; the second RLC belongs to the SCG, and the second RLC bearer is a bearer for performing data transmission through the second RLC, and may also be referred to as an SCG RLC bearer.

When the terminal detects that the MCG bearer cannot perform data transmission, the MCG link is indicated to be failed, at the moment, the terminal sends an MCG failure message to the MN to inform the MN that the current MCG link fails, the MN can switch the MN to reestablish the MCG link to perform data transmission after receiving the MCG failure message, or the MN sends an RRC connection release message after receiving the MCG failure message, and the UE enters an RRC IDLE state (RRC _ IDLE state) or an RRC INACTIVE state (RRC _ INACTIVE state). The MCG link failure may be a Radio Link Failure (RLF) or the like.

In the process that the terminal sends the MCG failure message to the MN, the terminal autonomously switches the main path of the separated load bearing from the MCG RLC load bearing to the SCG RLC load bearing because the main path failure is detected, and sends the MCG failure message to the MN through the SCG load bearing to carry out MCG load bearing fast recovery. However, the MN also fails to perform the MCG fast recovery (MCG fast recovery), and the terminal performs the RRC connection reestablishment.

In a possible implementation manner, in the process of fast MCG recovery by the MN, the terminal starts timing when sending an MCG failure message. If the terminal does not receive the feedback messages such as the RRC reconfiguration message, the RRC release message and the like sent by the MN within the specified time, the terminal defaults that the MN fails to perform the MCG fast recovery, and at the moment, the terminal performs the reestablishment of the RRC connection. Therefore, the terminal is prevented from waiting for the MN to perform MCG fast recovery indefinitely, and the reaction time of the terminal is shortened. Of course, if the terminal receives the RRC reconfiguration message or the RRC release message sent by the MN within the specified time, which indicates that the MN performs the MCG fast recovery successfully, the terminal does not need to perform the RRC connection re-establishment. The prescribed time may be implemented by a preset timer (timer).

In a possible implementation manner, in the process of fast MCG recovery by the MN, when the terminal detects that the SCG bearer cannot perform data transmission, it indicates that the SCG link fails, and at this time, the terminal cannot send an MCG failure message to the MN. In this case, the MN cannot receive the MCG failure message, and thus cannot perform MCG fast recovery. Therefore, when the terminal detects that the SCG bearer cannot perform data transmission, the terminal immediately performs RRC connection reestablishment. Therefore, the RRC connection is reestablished without waiting for overtime, thereby further shortening the reaction time of the terminal.

Step S403, when RRC connection reestablishment is performed, the main path is switched to the first RLC bearer.

In the process of reestablishing the RRC connection by the terminal, since the main path has been switched to the SCG RLC bearer to send the MCG failure information before, if the terminal does not switch the main path to the MCG RLC bearer when reestablishing the RRC connection, the terminal cannot send and receive the RRC message through the SRB 1. Therefore, when the terminal reestablishes the RRC connection, the main path needs to be switched to the MCG RLC bearer.

Optionally, for an implementation manner that the terminal switches the main path to the MCG RLC bearer, the main path may be actively switched to the MCG RLC bearer when the terminal reestablishes the RRC connection.

In one possible implementation manner, after step S401, the method further includes:

step S402, judging whether the main path of the separated load is the second RLC load.

When the terminal determines that the current main path is the SCG RLC bearer, step S403 is executed;

and when the terminal judges that the current main path is the MCG RLC bearing, the main path does not need to be switched.

For different terminals, when detecting the MCG link failure, some terminals perform MCG fast recovery and then perform RRC connection re-establishment, and some terminals directly perform RRC connection re-establishment. Therefore, for different terminals, when RRC connection reestablishment is performed, it is necessary to detect whether the current main path is MCG RLC bearer or SCG RLC bearer. If the current main path is detected to be MCG RLC bearing, the terminal does not need to switch the main path; and if the current main path is detected to be the SCG RLC bearer, the terminal needs to switch the main path to the MCG RLC bearer.

In one possible implementation, the terminal may be assisted by the network side (e.g., MN) to switch the primary path. In this embodiment, after step S403, the method further includes:

step S404, sending the first link recovery failure cause value to the first base station.

The first base station is a MN, and the first link failure recovery message is a quick recovery failure message that can be an MCG. When a terminal initiates a reestablishment request of RRC connection to the MN, the terminal adds a reestablishment reason value (reestablishment cause) of 'MCG quick recovery failure' in a reestablishment request message 'MCG quick recovery failure message', and then sends the reestablishment reason value (reestablishment cause) to the MN.

For the MN, after receiving the reestablishment request message with the reestablishment reason being "MCG fast recovery failed", the MN determines that the terminal has switched the main path of the split SRB1 to the SCG RLC bearer because of MCG fast recovery. Therefore, in order to send and receive the RRC message through the SRB1 after the terminal completes the reestablishment of the RRC connection, the MN adds an indication information in the RRC reestablishment message for indicating the UE to reconfigure the main path of the split SRB1 as an MCG RLC bearer.

Step S405, receiving indication information from the first base station, and switching the main path to the first RLC bearer.

When MN sends rebuild message to terminal, it sends indication information to terminal, and terminal switches main path to MCG RLC load according to indication information.

Optionally, in an embodiment of the present application, the method further includes step S406, sending and/or receiving an RRC message through the first radio link.

It is understood that the communication method described in the embodiment of the present application can be used in various dual connection scenarios, for example, EN-DC, NR DC, NGEN-DC, NE-DC, and the like, and the present application is not limited herein.

In the process of RRC connection reestablishment of the terminal, for various DC scenes, the essence of triggering RRC reestablishment by the terminal is to reestablish the PDCP layer, and in the process, only certain variables and stored data packets are operated, and the security configuration is updated, the main path is not operated, if the MCG rapid recovery failure is performed on the terminal, the main path is not switched to MCG RLC bearing, so that the configuration of the terminal side and the MN side is not aligned when the terminal and the MN perform RRC reestablishment, and the RRC reestablishment process cannot be completed.

Therefore, after the terminal fails to perform MCG fast recovery, the terminal automatically or in an MN assisted mode switches the main path to MCG RLC bearing, so that the terminal side configuration is aligned with the base station side configuration, and therefore the receiving and sending of the RRC message of the SRB1 can be separated in the RRC reestablishment process normally, the RRC reestablishment process is completed, the normal dual-connection communication of the terminal is maintained, and the communication quality is improved.

Optionally, in an embodiment of the present application, for an RRC reestablishment procedure in other situations, that is, the RRC reestablishment procedure includes a trigger cause of MCG failure recovery and other failure cases (failure cases), for example, Radio Link Failure (RLF), reconfiguration failure, handover failure (HO) failure, integrity protection check failure, and the like, if a current main path of a terminal is SCG, where a main path of the terminal may be configured as SCG for a network, or the terminal autonomously switches the main path to SCG, the UE autonomously switches the main path to MCG. Or the UE may also delete the morenthanone rlc configuration, where the morenthanone rlc configuration includes the settings of the primary path.

In the MCG fast recovery process, when the terminal sends uplink data to the MN through the separation SRB1, and when the terminal detects that the MCG bearer cannot perform data transmission, if the SN configures the SRB3, the terminal may also perform MCG fast recovery through the SRB 3.

Fig. 5 is a flowchart of a communication method according to an embodiment of the present application. As shown in fig. 5, the present embodiment provides a communication method, which is performed by a first base station or a device, such as a chip or a chip system, for the first base station. The method comprises the following steps:

step S503, sending the first request information to the second base station.

The method for bearer recovery provided by the present application may be based on the scheme described in fig. 4. In the following, the first base station is MN, and the second base station is SN.

Wherein, the first request information is used for requesting whether the SN supports MCG fast recovery between the MN and the terminal through the SRB 3.

Step S504, receiving first feedback information from the second base station in response to the first request information.

The first feedback information means that the SN feeds back to the MN whether the MN supports MCG fast recovery between the MN and the terminal through the SRB3 according to the first request information. Or, the first feedback information is used to indicate whether the SN accommodates/supports MCG fast recovery through SRB 3. SRB3 may refer to an SRB established directly between a SN and a terminal.

Step S505, according to the first feedback information, instructs the terminal to perform recovery of the first radio link failure through the SRB 3.

The indicating of the terminal to perform the recovery of the first radio link failure through the SRB3 may include sending, to the terminal, configurations of the second base station to perform MCG fast recovery through the SRB3, where the configurations may include timer (timer) information.

After the MN receives the first feedback information, if the first feedback information indicates that the SN does not support the MCG fast recovery between the MN and the terminal through the SRB3, at this time, the MN either carries out the MCG fast recovery through the separated SRB1 or triggers the terminal to carry out RRC connection reestablishment; if the first feedback information indicates that the SN supports MCG fast recovery between the MN and the terminal through the SRB3, the MN sends related configuration of the SRB3 of the SN to the terminal for MCG fast recovery. Alternatively, the relevant configuration of the SRB3 of the SN may be determined in whole or in part by the MN.

Optionally, in an embodiment of the present application, before step S503, that is, before the MN performs MCG fast recovery through SRB3, the MN may determine whether the SN supports signaling to the terminal through SRB 3. The method further comprises the following steps:

step S501, sending query information to the second base station.

The query information may also be referred to as request information. The query information sent by the MN to the SN is used to query whether the SN supports SRB 3. Sending the query message is a prerequisite for whether the SN supports MCG fast recovery for the MN.

Accordingly, the SN receives the query information and sends a response message responding to the query information to the MN.

Step S502, receiving response information sent by the second base station.

After the MN receives the response information, if the SN does not support the SRB3, the SN is indicated to be incapable of carrying out signaling transmission with the terminal, namely the SN does not support the MN to carry out MCG quick recovery; if the query result is that the SN supports SRB3, steps S503-S505 are performed.

In the embodiment of the application, when the MN requests the SN to support MCG fast restoration through SRB3, it is queried whether the SN supports SRB3 and whether MCG fast restoration through SRB3 is supported, and then a resource for requesting the terminal to configure the SN to perform MCG fast restoration through SRB3 is performed, so as to avoid the problem of too long service interruption time caused by finding that the SN does not support MCG fast restoration through SRB3 after the MN requests the terminal to configure the SN to perform MCG fast restoration through SRB3 in order to bear the load, thereby fast restoring service transmission and improving communication quality.

Optionally, in an embodiment of the present application, after the MN performs MCG fast recovery through the SRB3, the method further includes:

step S506, sending the second request information to the second base station.

Wherein the second request information is for requesting the SN to release the resource for MCG fast recovery through SRB 3.

Accordingly, the SN receives the request information, and transmits second feedback information in response to the request information to the MN.

After the MN succeeds in MCG fast restoration through SRB3 or fails in MCG fast restoration, in order to avoid that the process always occupies the resources of the terminal, the MN needs to let the terminal release the configured resources for MCG fast restoration through SRB 3.

Step S507, receiving second feedback information from the second base station in response to the second request information.

Step S508, the terminal is requested to release the configuration for the first radio link failure recovery by the SRB 3.

After the MN receives the feedback information sent by the SN, if the feedback information indicates that the SN releases/cancels the configuration of MCG quick recovery through the SRB3, the MN requests the terminal to release/cancel the corresponding configuration in the SN; if the feedback information indicates that the SN does not release/cancel the configuration for MCG fast restoration through the SRB3, the MN does not request the terminal to release/cancel the configuration for MCG fast restoration.

According to the embodiment of the application, after the MN completes the flow of MCG fast recovery through the SRB3, the previous configuration of the terminal is cancelled, so that the occupation of resources of the terminal is avoided.

Fig. 6 is a flowchart of a communication method according to an embodiment of the present application. As shown in fig. 6, the present embodiment provides a communication method, which is performed by a second base station or a device for the second base station, such as a chip or a chip system. The method comprises the following steps:

step S601, receiving query information sent by the first base station.

Wherein the query information is used to query whether the SN supports SRB 3.

Step S602, sending response information to the first base station.

The response information may be that the SN does not support SRB3, indicating that the SN cannot perform signaling information transmission with the terminal; SRB3 may also be supported for the SN to indicate that the SN is capable of signaling information to and from the terminal.

Step S603, receiving the first request information sent by the first base station.

The first request information is used for requesting whether the SN supports SRB3 for MCG fast recovery.

Step S604, sending first feedback information responding to the first request information to the first base station.

The first feedback information is used for triggering the MN to instruct the terminal to perform the configuration of fast recovery of the MCG through the SRB 3.

Step S605 receives the second request message sent by the first base station.

Wherein the second request information is used for requesting whether the SN releases the resource for MCG fast recovery through SRB 3.

Step S606, sending the second feedback information to the first base station.

Wherein, the second feedback information is used to trigger the MN to instruct the terminal to perform MCG fast recovery through SRB 3.

In the embodiment of the application, when the SN receives the MN request to support the MCG fast recovery through SRB3, after inquiring whether the SN supports SRB3 and whether the SN supports the MCG fast recovery through SRB3, the SN is told to the MN, and then the MN requests the terminal to configure the resource for the SN to perform the MCG fast recovery through SRB3, so that the MCG fast recovery through SRB3 is realized.

Examples of a communication method and a method of communication provided by the present application are described above in detail. It is to be understood that the communication device includes hardware structures and/or software modules for performing the respective functions in order to realize the above functions. Those of skill in the art would readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The communication device may be divided into functional units according to the above method examples, for example, each function may be divided into each functional unit, or two or more functions may be integrated into one processing unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. It should be noted that the division of the units in the present application is schematic, and is only one division of logic functions, and there may be another division manner in actual implementation.

For example, the communication device 700 shown in fig. 7 includes a transceiver 701 and a processing unit 702.

In an embodiment of the present application, the communication apparatus 700 is configured to support a terminal device to implement a function of a terminal in a communication method provided in an embodiment of the present application, for example, the processing unit 702 may be configured to switch a primary path of a split bearer from a first radio link control RLC bearer to a second RLC bearer when a first radio link fails; and switching the main path to the first RLC bearer when RRC connection reestablishment is performed. The first wireless link refers to an MCG link between the terminal and the MN, and the bearer for data transmission through the MCG link is an MCG bearer; the second wireless link refers to an SCG link between the terminal and the SN, and the bearer for data transmission through the SCG link is an SCG bearer. The transceiving unit 701 is used for data/signaling transmission between the terminal and other communication devices, for example, other terminals or access network devices.

The terminal may obtain that the MCG link fails through detection, and then initiate an MCG fast recovery process, and when the MCG fast recovery is unsuccessful, the terminal further performs an RRC reestablishment process, and for detailed description of the series of processes, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiment shown in fig. 4, which are not described again.

In a possible implementation manner, the processing unit 702 is configured to determine that the MCG fails to recover and perform RRC connection reestablishment when the RRC reconfiguration message or the RRC release message of the MN is not received within a preset time. For a specific way of determining how to fail to quickly recover the MCG within the preset time, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiment shown in fig. 4, which are not described in detail.

In one possible implementation manner, the processing unit 702 is further configured to determine that the MCG fast recovery fails and perform RRC connection re-establishment when the SCG bearer fails during the MCG fast recovery. For a specific way of how to determine the SCG bearer failure, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiment shown in fig. 4, which are not described in detail.

In one possible implementation manner, the processing unit 702 is configured to determine whether the primary path of the split bearer is the second RLC bearer. When the processing unit 702 determines that the current main path is an SCG RLC bearer, the main path is switched to an MCG RLC bearer; when the processing unit 702 determines that the current primary path is the MCG RLC bearer, it indicates that the primary path does not need to be switched.

In one possible implementation, the processing unit 702 transceiver unit 701 is configured to send the first link recovery failure cause value to the first base station.

Wherein, the first base station is MN, and the first link recovery failure message may be an MCG quick recovery failure message.

For a specific description of the first link failure cause value, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiment shown in fig. 4, which are not described in detail.

The transceiver unit 701 is further configured to receive indication information from the first base station, and switch the primary path to the first RLC bearer.

In one possible implementation, the processing unit 702 is configured to control the transceiving unit 701 to transmit and/or receive an RRC message through the first radio link.

For a detailed description of operations executed by each functional unit of the communication apparatus 700, for example, reference may be made to behaviors of a terminal in an embodiment of a communication method provided in the present application, for example, relevant contents in the embodiment shown in fig. 4, which are not described in detail.

In another embodiment of the present application, in terms of hardware implementation, the functions of the processing unit 702 may be executed by a processor, and the functions of the transceiver unit 701 may be executed by a transceiver (transmitter/receiver) and/or a communication interface, where the processing unit 702 may be embedded in a processor of the terminal or independent from the processor of the terminal in a hardware form, or may be stored in a memory of the terminal or the base station in a software form, so that the processor may invoke to execute operations corresponding to the above functional units.

The device provided by the embodiment of the application automatically or through MN assistance mode switches the main path to MCG RLC bearing after the terminal has failed in MCG fast recovery, so that the terminal side configuration is aligned with the base station side configuration, and the receiving and sending of the RRC message of the SRB1 separated in the RRC reestablishment process can be normally carried out, thereby completing the RRC reestablishment process, maintaining the normal dual-connection communication of the terminal and improving the communication quality.

For example, the communication apparatus 800 shown in fig. 8 includes a transceiver 801 and a processing unit 802.

In an embodiment of the present application, the communication apparatus 800 is configured to support a base station to implement a function of a first base station in a communication method provided in an embodiment of the present application, for example, the transceiver unit 801 is configured to send first request information to a second base station; the transceiving unit 801 is further configured to receive first feedback information from the second base station in response to the first request information; the processing unit 802 is configured to request the terminal to configure a resource for the second base station to perform the first radio link failure recovery through the SRB 3. Wherein, the first base station may be MN of the terminal during DC communication, and the second base station may be SN of the terminal during DC communication.

Wherein, the first request information is used for requesting whether the SN supports the result of MCG fast recovery between the MN and the terminal through the SRB 3. The first feedback information means that the SN feeds back to the MN whether the MN supports MCG fast recovery between the MN and the terminal through the SRB 3. Or, the first feedback information is used to indicate whether the SN accommodates/supports MCG fast recovery through SRB 3. For how to implement a specific implementation manner of how the terminal performs MCG fast recovery through SRB3, reference may be made to some embodiments of the method in this application, for example, related contents in the embodiment shown in fig. 5, which are not described in detail.

In one possible implementation, the transceiver unit 801 is configured to send query information to the second base station; the transceiving unit 801 is further configured to receive response information sent by the second base station in response to the query information. The query information may also be referred to as request information. The query information sent by the MN to the SN is used to query whether the SN supports SRB 3. For a specific implementation manner how to implement how to query whether SN supports SRB3, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiment shown in fig. 5, which are not described in detail.

In one possible implementation manner, after the MN performs MCG fast recovery through SRB3, the transceiver unit 801 is configured to send the second request message to the second base station; the transceiving unit 801 is further configured to receive second feedback information from the second base station in response to the second request information; the processing unit 802 is configured to request the terminal to release the configuration for the first radio link failure recovery via the SRB 3. For how to implement a specific implementation manner of requesting the terminal to release the resource for MCG fast recovery through SRB3, reference may be made to some embodiments of the method in this application, for example, relevant contents in the embodiment shown in fig. 5, which are not described in detail herein.

In another embodiment of the present application, the communication apparatus 800 is configured to support a base station to implement the function of a second base station in the communication method provided in the embodiment of the present application, for example, the transceiver unit 801 is configured to receive first request information sent by a first base station; the transceiving unit 801 is further configured to send first feedback information to the first base station. Wherein, the second base station may be an SN of the terminal during the DC communication.

The first request information is used for requesting whether the SN supports SRB3 for MCG fast recovery, and the first feedback information is used for triggering the MN to instruct the terminal to perform resources for MCG fast recovery through SRB 3. For how to implement a specific implementation manner of whether the SN supports MCG fast recovery through SRB3, reference may be made to some embodiments of the method of the present application, for example, relevant contents in the embodiments shown in fig. 5 to 6, which are not described in detail.

In one possible implementation manner, the transceiver unit 801 is configured to receive query information sent by a first base station; the transceiving unit 801 is further configured to send response information to the first base station. The query information is used for querying whether the SN supports SRB3, and the response information may be that the SN does not support SRB3, which indicates that the SN cannot transmit signaling information with the terminal; SRB3 may also be supported for the SN to indicate that the SN is capable of signaling information to and from the terminal. For a specific implementation manner of how to implement how to query whether SRB3 is supported by SN, reference may be made to related contents in some embodiments of the method of the present application, for example, the embodiments shown in fig. 5 to 6, which are not described in detail.

In one possible implementation manner, the transceiver unit 801 is configured to receive second request information sent by the first base station; the transceiving unit 801 is further configured to send second feedback information to the first base station. The second request information is used for requesting whether the SN releases the resource for fast recovery of MCG through SRB3, and the second feedback information is used for triggering the MN to instruct the terminal to release the configuration for fast recovery of MCG through SRB 3. For a specific implementation manner how to implement how to determine whether to release the resource for performing the MCG fast recovery through the SRB3, reference may be made to some embodiments of the method of the present application, for example, related contents in the embodiments shown in fig. 5 to 6, which are not described in detail.

For a detailed description of operations executed by each functional unit of the communication apparatus 800, for example, reference may be made to behaviors of access network devices (primary nodes/secondary nodes) in the embodiments of the communication method provided in the present application, for example, relevant contents in the embodiments shown in fig. 5 to fig. 6, which are not described again.

In another embodiment of the present application, in terms of hardware implementation, the functions of the processing unit 802 may be executed by a processor, and the functions of the transceiver unit 801 may be executed by a transceiver (transmitter/receiver) and/or a communication interface, where the processing unit 802 may be embedded in a processor of the terminal or independent from the processor of the terminal in a hardware form, or may be stored in a memory of the terminal or the base station in a software form, so that the processor may invoke the operations corresponding to the above respective functional units.

In the embodiment of the application, when the MN requests the SN to support MCG fast restoration through SRB3, it is queried whether the SN supports SRB3 and whether MCG fast restoration through SRB3 is supported, and then a resource for requesting the terminal to configure the SN to perform MCG fast restoration through SRB3 is performed, so as to avoid the problem of too long service interruption time caused by finding that the SN does not support MCG fast restoration through SRB3 after the MN requests the terminal to configure the SN to perform MCG fast restoration through SRB3 in the prior art.

Fig. 9 shows a schematic structural diagram of a communication device 900 provided in the present application. The communication apparatus 900 may be used to implement the communication method and the communication method described in the above method embodiments. The communication device 800 may be a chip, a terminal, a base station or other wireless communication device, etc.

Communications apparatus 900 includes one or more processors 901, and the one or more processors 901 can enable communications apparatus 700 to implement the communications methods performed by a terminal (UE) described in embodiments herein, such as the methods performed by the terminal in the embodiment shown in fig. 4; alternatively, the one or more processors 901 may support the communication device 800 to implement the communication method performed by the base station in the embodiments of the present application, for example, the method performed by the base station (the first base station or the second base station) in the embodiments shown in fig. 5 to 6.

The processor 901 may be a general purpose processor or a special purpose processor. For example, the processor 901 may include a Central Processing Unit (CPU) and/or a baseband processor. Where the baseband processor may be configured to process communication data (e.g., the first message described above), the CPU may be configured to implement corresponding control and processing functions, execute software programs, and process data of the software programs.

Further, the communication apparatus 900 may further include a transceiver 905 for implementing input (reception) and output (transmission) of signals.

For example, the communication apparatus 900 may be a chip, and the transceiver 905 may be an input and/or output circuit of the chip, or the transceiver 905 may be an interface circuit of the chip, and the chip may be a component of a UE or a base station or other wireless communication device.

Also for example, communications apparatus 900 can be a UE or a base station. The transceiver unit 905 may include a transceiver or a radio frequency chip. The transceiving unit 905 may further comprise a communication interface.

Optionally, the communication apparatus 900 may further include an antenna 906, which may be used to support the transceiver 905 to implement the transceiving function of the communication apparatus 900.

Optionally, the communication device 900 may include one or more memories 902, on which programs (also instructions or codes) 903 are stored, and the programs 903 may be executed by the processor 901, so that the processor 901 performs the methods described in the above method embodiments. Optionally, data may also be stored in the memory 902. Alternatively, the processor 901 may also read data (e.g., predefined information) stored in the memory 902, which may be stored at the same memory address as the program 903, or which may be stored at a different memory address from the program 903.

The processor 901 and the memory 902 may be provided separately or integrated together, for example, on a single board or a System On Chip (SOC).

In one possible design, the communication apparatus 900 is a terminal or a chip available for a terminal, the terminal has a function of DC communication, and the processor 901 is configured to switch the main path of the split bearer from the first radio link control RLC bearer to the second RLC bearer when the first radio link fails; and switching the main path to the first RLC bearer when the RRC connection is reestablished. The terminal has a first radio link with the first base station and a second radio link with the second base station, and is configured to separate bearers, where the separate bearers include a first RLC bearer corresponding to the first radio link and a second RLC bearer corresponding to the second radio link.

In one possible design, the communication device 900 is a base station, which may act as a master node in DC communications, or a chip that may be used for access network equipment. For example, the transceiver 905 is configured to send a first request message to a second base station to request whether the base station supports MCG fast recovery through an SRB between the second base station and a terminal; and receiving first feedback information from a second base station in response to the first request information; processor 901 is configured to request the terminal to perform MCG fast recovery through SRB3 according to the first feedback information. Wherein the second base station is a secondary node in DC communication.

The base station may serve as a secondary node in DC communication, for example, the transceiving unit 905 is configured to receive first request information sent by the first base station, and determine whether to support MCG fast recovery by the first base station through SRB 3; and is further configured to send first feedback information to the first base station. Wherein the first base station is a master node in DC communication.

For a detailed description of operations performed by the communication apparatus 900 in the above various possible designs, reference may be made to behaviors of a terminal in the embodiment of the communication method or a base station (a primary node/a secondary node) in the embodiment of the communication method provided in the present application, for example, related contents in the embodiments shown in fig. 4 to fig. 6, which are not described in detail.

It should be understood that the steps of the above-described method embodiments may be performed by logic circuits in the form of hardware or instructions in the form of software in the processor 901. The processor 801 may be a CPU, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic device, such as a discrete gate, a transistor logic device, or a discrete hardware component.

As shown in fig. 10, terminal 1000 can include a processor, memory, control circuitry, antenna, and input-output devices. The processor is mainly used for processing communication protocols and communication data and controlling the whole terminal. For example, the processor generates a first message and then transmits the first message through the control circuit and the antenna. The memory is mainly used for storing programs and data, such as communication protocols and the above configuration information. The control circuit is mainly used for converting baseband signals and radio frequency signals and processing the radio frequency signals. The control circuit and the antenna together, which may also be called a transceiver, are mainly used for transceiving radio frequency signals in the form of electromagnetic waves. The input/output device is, for example, a touch screen, a display screen, or a keyboard, and is mainly used for receiving data input by a user and outputting data to the user.

The processor can read the program in the memory, interpret and execute the instructions contained in the program, and process the data in the program. When information needs to be sent through the antenna, the processor carries out baseband processing on the information to be sent and then outputs baseband signals to the radio frequency circuit, the radio frequency circuit carries out radio frequency processing on the baseband signals to obtain radio frequency signals, and the radio frequency signals are sent out in an electromagnetic wave mode through the antenna. When an electromagnetic wave (i.e., a radio frequency signal) carrying information reaches a terminal, a radio frequency circuit receives the radio frequency signal through an antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to a processor, and the processor converts the baseband signal into information and processes the information.

Those skilled in the art will appreciate that fig. 10 shows only one memory and one processor for ease of illustration. In an actual terminal, there may be multiple processors and multiple memories. The memory may also be referred to as a storage medium or a storage device, and the present application is not limited thereto.

As an alternative implementation, the processor in fig. 10 may integrate functions of a baseband processor and a CPU, and those skilled in the art will understand that the baseband processor and the CPU may also be independent processors, and are interconnected through a bus or the like. Those skilled in the art will appreciate that the terminal may include a plurality of baseband processors to accommodate different network formats, may include a plurality of CPUs to enhance its processing capability, and various components of the terminal may be connected through various buses. The baseband processor may also be referred to as a baseband processing circuit or baseband processing chip. The CPU may also be referred to as a central processing circuit or a central processing chip. The function of processing the communication protocol and the communication data may be built in the processor, or may be stored in the memory in the form of a program, and the processor executes the program in the memory to realize the baseband processing function.

In this application, an antenna and a control circuit with transceiving functions can be regarded as a transceiving unit 1001 of the terminal 1000, which is used for supporting a receiving function in the terminal implementation method embodiment, or for supporting a transmitting function in the terminal implementation method embodiment. A processor having processing functionality is considered to be processing unit 1002 of terminal 1000. As shown in fig. 10, terminal 1000 includes a transceiving unit 1001 and a processing unit 1002. A transceiver unit may also be referred to as a transceiver, a transceiving device, etc. Alternatively, a device used for implementing a receiving function in the transceiving unit 1001 may be regarded as a receiving unit, and a device used for implementing a transmitting function in the transceiving unit 1001 may be regarded as a transmitting unit, that is, the transceiving unit 1001 includes a receiving unit and a transmitting unit, the receiving unit may also be referred to as a receiver, an input port, a receiving circuit, and the like, and the transmitting unit may be referred to as a transmitter, a transmitting circuit, and the like.

The processor 1002 may be configured to execute the program stored in the memory to control the transceiver unit 1001 to receive and/or transmit signals, so as to implement the functions of the terminal in the above-described method embodiments. As an implementation manner, the function of the transceiving unit 1001 may be considered to be implemented by a transceiving circuit or a transceiving dedicated chip.

Wherein the processor 1002 may perform the functions of the processing unit 702 in the communication apparatus 700 shown in fig. 7 or the processor 901 in the communication apparatus 900 shown in fig. 9; the transceiver unit 1001 may execute the functions of the transceiver unit 701 in the communication device 700 or the transceiver unit 905 in the communication device 900 shown in fig. 7, which is not described in detail.

In a case that the communication apparatus 800 is a base station, fig. 11 is a schematic structural diagram of a base station according to an embodiment of the present application. As shown in fig. 11, the base station can be applied to the system shown in fig. 1, and performs the function of the access network device in the above method embodiment, and the base station has the function of serving as a primary node or a secondary node in DC communication. Base station 1100 may include one or more DUs 1101 and one or more CUs 1102. The DU1101 may include at least one antenna 11011, at least one radio frequency unit 11012, at least one processor 11013, and at least one memory 11014. The DU1101 portion is mainly used for transceiving radio frequency signals, converting radio frequency signals and baseband signals, and partially processing baseband. CU1102 may include at least one processor 11022 and at least one memory 11021. CU1102 and DU1101 may communicate via interfaces, wherein a Control Plane (Control Plane) interface may be Fs-C, such as F1-C, and a User Plane (User Plane) interface may be Fs-U, such as F1-U.

The CU1102 section is mainly used for performing baseband processing, controlling a base station, and the like. The DU1101 and CU1102 may be physically located together or physically located separately, i.e. distributed base stations. The CU1102 is a control center of the base station, which may also be referred to as a processing unit, and is mainly used to perform baseband processing functions. For example, the CU1102 may be configured to control the base station to perform the operation procedure related to the network device in the above method embodiment.

Specifically, the baseband processing on the CU and the DU may be divided according to protocol layers of the wireless network, for example, functions of a Packet Data Convergence Protocol (PDCP) layer and protocol layers above the PDCP layer are set in the CU, and functions of protocol layers below the PDCP layer, for example, functions of a Radio Link Control (RLC) layer and a Medium Access Control (MAC) layer, are set in the DU. For another example, a CU implements Radio Resource Control (RRC) and Packet Data Convergence Protocol (PDCP) functions, and a DU implements Radio Link Control (RLC), Medium Access Control (MAC) and Physical (PHY) functions.

Further, base station 1100 may optionally include one or more radio frequency units (RUs), one or more DUs, and one or more CUs. Wherein, the DU may include at least one processor 11013 and at least one memory 11014, the RU may include at least one antenna 11011 and at least one radio frequency unit 11012, and the CU may include at least one processor 11022 and at least one memory 11021.

In an example, the CU1102 may be formed by one or more boards, where the multiple boards may jointly support a radio access network with a single access indication (e.g., a 5G network), or may respectively support radio access networks with different access schemes (e.g., an LTE network, a 5G network, or other networks). The memory 11021 and the processor 11022 may serve one or more boards. That is, the memory and processor may be provided separately on each board. Multiple boards may share the same memory and processor. In addition, each single board can be provided with necessary circuits. The DU1101 may be formed by one or more boards, where the boards may jointly support a radio access network with a single access instruction (e.g., a 5G network), and may also respectively support radio access networks with different access schemes (e.g., an LTE network, a 5G network, or other networks). The memory 11014 and the processor 11013 may serve one or more boards. That is, the memory and processor may be provided separately on each board. Multiple boards may share the same memory and processor. In addition, each single board can be provided with necessary circuits.

Wherein the DU and CU may together perform the function of the processor 802 in the communication apparatus 800 shown in fig. 8 or the function of the processor 901 in the communication apparatus 900 shown in fig. 9; the transceiver unit 1001 may perform the functions of the transceiver unit 801 in the communication device 800 shown in fig. 8 or the functions of the transceiver unit 905 in the communication device 900, which are not described in detail herein.

The application also provides a communication system, which comprises a first base station and a second base station, wherein the first base station can be used as a main node, and the second base station can be used as an auxiliary node.

Optionally, the communication system further includes a terminal, and the terminal may access the first base station and the second base station simultaneously. For the functions of each device in the communication system, reference may be made to the related descriptions of other embodiments of the present application, which are not described in detail.

It is clear to those skilled in the art that the descriptions of the embodiments provided in the present application may be referred to each other, and for convenience and brevity of description, for example, the functions and steps of the apparatuses and the devices provided in the embodiments of the present application may be referred to the relevant description of the method embodiments of the present application, and the method embodiments and the apparatus embodiments may be referred to, combined or cited as each other.

In the several embodiments provided in the present application, the disclosed system, apparatus and method may be implemented in other ways. For example, some features of the method embodiments described above may be omitted, or not performed. The above-described embodiments of the apparatus are merely exemplary, the division of the unit is only one logical function division, and there may be other division ways in actual implementation, and a plurality of units or components may be combined or integrated into another system. In addition, the coupling between the units or the coupling between the components may be direct coupling or indirect coupling, and the coupling includes electrical, mechanical or other connections.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the processes do not mean the execution sequence, and the execution sequence of the processes should be determined by the functions and the inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application. In addition, in the embodiments of the present application, a terminal and/or a network device may perform some or all of the steps in the embodiments of the present application, and these steps or operations are merely examples, and the embodiments of the present application may also perform other operations or variations of various operations. Further, the various steps may be performed in a different order presented in the embodiments of the application, and not all operations in the embodiments of the application may be performed.

Claims

A method of communication for a terminal supporting dual connectivity, the terminal having a first radio link with a first base station and a second radio link with a second base station, the terminal being configured to separate bearers, the method comprising:

when the first radio link fails, switching the main path of the separated bearer from a first Radio Link Control (RLC) bearer to a second RLC bearer, wherein the separated bearer comprises the first RLC bearer and the second RLC bearer, the first RLC bearer corresponds to the first radio link, and the second RLC bearer corresponds to the second radio link;

and when the RRC connection is reestablished, switching the main path to the first RLC bearer.
The method according to claim 1, wherein the switching the primary path to the first RLC bearer when RRC connection re-establishment is performed comprises:

judging whether the main path of the separated load is the second RLC load;

and when the main path is the second RLC bearing, switching the main path to the first RLC bearing.
The method of claim 1, further comprising:

and when the RRC reconfiguration message or the RRC release message of the first base station is not received within the preset time, determining that the first radio link fails to recover, and reestablishing the RRC connection.
The method of claim 1, further comprising:

in the process of recovering from the failure of the first radio link, when the second radio link fails, determining that the recovery of the first radio link fails, and performing the RRC connection reestablishment.
The method according to any one of claims 1-4, further comprising:

sending the first link recovery failure cause value to the first base station, where the first link recovery failure cause value is used to trigger the first base station to generate indication information indicating that the main path is switched to the first RLC bearer;

and receiving the indication information from the first base station, and switching the main path to the first RLC bearing.
A method of communication, the method performed by a first base station, comprising:

sending first request information to a second base station; the first request information is used for requesting whether the second base station supports the first base station to perform first radio link failure recovery through a Signaling Radio Bearer (SRB) between the second base station and a terminal, wherein the first radio link is a radio link between the first base station and the terminal;

receiving first feedback information from the second base station in response to the first request information;

and indicating the terminal to recover the first radio link failure through the SRB according to the first feedback information.
The method of claim 6, wherein before sending the first request message to the second base station, the method comprises:

sending query information to the second base station, wherein the query information is used for querying whether the second base station supports the SRB;

receiving response information from the second base station; the response information is used for indicating that the second base station supports the SRB.
The method of claim 6, further comprising:

sending second request information to the second base station; the second request information is used for requesting whether to release the resource for the first radio link failure recovery through the SRB;

receiving second feedback information from the second base station in response to the second request information;

requesting the terminal to release the configuration of the first radio link failure recovery through the SRB in the second base station.
A method of communication, the method performed by a second base station, comprising:

receiving first request information sent by a first base station, where the first request information is used to request whether the second base station supports the first base station to perform first radio link failure recovery through a Signaling Radio Bearer (SRB) between the second base station and a terminal, and the first radio link is a radio link between the first base station and the terminal;

and sending first feedback information to the first base station, wherein the first feedback information is used for triggering the first base station to indicate the terminal to recover the first radio link failure through the SRB.
The method of claim 9, wherein receiving the first request message sent by the first base station comprises:

receiving query information sent by the first base station, where the query information is used to query whether the second base station supports the SRB;

sending response information to the first base station; the response information is used for indicating that the second base station supports the SRB.
The method of claim 9, further comprising:

receiving second request information sent by the first base station; the second request information is used for requesting whether to release the resource for performing the first radio link failure recovery through the SRB;

sending second feedback information to the first base station; the second feedback information is used to trigger the first base station to request the terminal to release the configuration of the first radio link failure recovery through the SRB in the second base station.
A communications apparatus for a terminal supporting dual connectivity, the terminal having a first radio link with a first base station and a second radio link with a second base station, the terminal being configured to separate bearers, the apparatus comprising:

a processing unit, configured to switch a main path of the split bearer from a first radio link control, RLC, bearer to a second RLC bearer when the first radio link fails, where the split bearer includes the first RLC bearer and the second RLC bearer, the first RLC bearer corresponds to the first radio link, and the second RLC bearer corresponds to the second radio link; and

and when the RRC connection is reestablished, switching the main path to the first RLC bearer.
The apparatus of claim 12,

the processing unit is configured to determine whether the main path of the split bearer is the second RLC bearer; and when the main path is the second RLC bearer, switching the main path to the first RLC bearer.
The apparatus of claim 12,

the processing unit is configured to determine that the first radio link fails to recover and perform RRC connection reestablishment when the RRC reconfiguration message or the RRC release message of the first base station is not received within a preset time.
The apparatus according to any of claims 12-14, wherein the processing unit is further configured to determine that the first radio link fails to recover and perform the RRC connection re-establishment when the second radio link fails in a process of recovering from the first radio link failure.
The apparatus according to any one of claims 12-15, further comprising: a receiving and sending unit for receiving and sending the data,

the transceiver unit is configured to send the first link recovery failure cause value to the first base station, where the first link recovery failure cause value is used to trigger the first base station to generate indication information indicating that the main path is switched to the first RLC bearer; and

and receiving the indication information from the first base station, and switching the main path to the first RLC bearing.
A communications apparatus, for use with a first base station, the apparatus comprising:

a transceiving unit, configured to send first request information to a second base station; the first request information is used for requesting whether the second base station supports the first base station to perform first radio link failure recovery through a Signaling Radio Bearer (SRB) between the second base station and a terminal, wherein the first radio link is a radio link between the first base station and the terminal;

the transceiver unit is further configured to receive first feedback information from the second base station in response to the first request information;

and the processing unit is used for indicating the terminal to recover the first radio link failure through the SRB according to the first feedback information.
The apparatus of claim 17,

the transceiver unit is further configured to send query information to the second base station, where the query information is used to query whether the second base station supports the SRB; and

receiving response information from the second base station; the response information is used for indicating that the second base station supports the SRB.
The apparatus of claim 17,

the transceiver unit is further configured to send second request information to the second base station; the second request information is used for requesting whether to release the resource for the first radio link failure recovery through the SRB;

the transceiver unit is further configured to receive second feedback information from the second base station in response to the second request information;

the processing unit is further configured to request the terminal to release the configuration of the first radio link failure recovery through the SRB in the second base station.
A communications apparatus, for a second base station, the apparatus comprising:

a transceiver unit, configured to receive first request information sent by a first base station, where the first request information is used to request whether the second base station supports the first base station to perform first radio link failure recovery through a signaling radio bearer SRB between the second base station and a terminal, where the first radio link is a radio link between the first base station and the terminal;

the transceiver unit is further configured to send first feedback information to the first base station, where the first feedback information is used to trigger the first base station to instruct the terminal to perform recovery of the first radio link failure through the SRB.
The apparatus of claim 20,

the transceiver unit is further configured to receive query information sent by the first base station, where the query information is used to query whether the second base station supports the SRB;

the transceiver unit is further configured to send response information to the first base station; the response information is used for indicating that the second base station supports the SRB.
The apparatus of claim 20,

the transceiver unit is further configured to receive request information sent by the first base station; the request information is used for requesting whether to release the resource for the first radio link failure recovery through the SRB;

the transceiver unit is further configured to send second feedback information to the first base station; the second feedback information is used for triggering the first base station to request the terminal to release the configuration of the first radio link failure recovery through the SRB in the second base station.
A communications apparatus comprising at least one processor configured to execute instructions stored in a memory to cause a terminal to perform the method of any of claims 1-5.
A communications apparatus comprising at least one processor configured to execute instructions stored in a memory to cause a base station to perform the method of any of claims 6-8 or claims 9-11.
A terminal device for performing the method of any one of claims 1-5.
A base station for performing the method of any of claims 6-8 or claims 9-11.
A computer storage medium having instructions stored thereon, which when executed on a computer, cause the computer to perform the method of any one of claims 1-11.
A computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of any of claims 1-11.
A communication system comprising a first base station and a second base station, wherein the first base station is used as a primary node of a terminal, the second base station is used as a secondary node of the terminal, the first base station is used for executing the method according to any one of claims 6-8, and the second base station is used for executing the method according to any one of claims 9-11.