CN115707046A

CN115707046A - Cell access method, communication device and network equipment

Info

Publication number: CN115707046A
Application number: CN202110892132.XA
Authority: CN
Inventors: 郑午阳; 胡星星
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-08-04
Filing date: 2021-08-04
Publication date: 2023-02-17
Also published as: WO2023011266A1

Abstract

The embodiment of the application discloses a method for accessing a cell, a communication device and network equipment, wherein the method is used for accessing a terminal into a target cell and comprises the following steps: the method comprises the steps of sending indication information corresponding to second communication configuration to first network equipment based on the first communication configuration, receiving first confirmation information sent by the first network equipment, and sending an access notification message to the first network equipment based on the second communication configuration; or sending an access notification message to the first network device based on the first communication configuration, receiving second acknowledgement information sent by the first network device, and communicating with the first network device based on a second communication configuration. By adopting the embodiment of the application, the terminal can match the communication configuration used by the cell access with the communication configuration of the network side, and the reliability of signaling and data transmission is improved.

Description

Cell access method, communication device and network equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method, a communications apparatus, and a network device for accessing a cell.

Background

In a wireless communication system, due to the influence of factors such as mobility of a terminal or a change in a cell channel environment, a terminal may access a new cell, for example, switch from a source cell to a target cell, or add a primary secondary cell (PSCell) as a target cell, so as to obtain better data transmission quality.

Since the first communication configuration used by the terminal side is updated to the second communication configuration corresponding to the target cell during the process of accessing the target cell, but the base station (which may be a master base station or a source base station in different scenarios) accessed by the terminal before accessing the target cell still communicates with the terminal using the first communication configuration, this may cause errors in information, such as signaling and data, transmitted between the master base station or the source base station and the terminal during the process of accessing the target cell by the terminal.

Disclosure of Invention

The technical problem to be solved in the embodiments of the present application is to provide a method, a communication device, and a network device for accessing a cell, so as to solve a problem that information transmission is wrong when a terminal performs cell access.

In a first aspect, an embodiment of the present application provides a method for accessing a cell, where the method is used for a terminal to access a target cell, and the method includes:

the method comprises the steps that indication information corresponding to second communication configuration is sent to first network equipment based on the first communication configuration, first confirmation information sent by the first network equipment is received, and an access notification message is sent to the first network equipment based on the second communication configuration;

by adopting the mode, when the first network equipment uses the first communication configuration, the terminal also uses the first communication configuration to send the indication information to inform the first network equipment of the cell to be accessed, so that the first network equipment can determine the second communication configuration matched with the target cell, and in the subsequent process of cell access, the terminal and the first network equipment can both use the second communication configuration to communicate, thereby avoiding the problem of information transmission error caused by mismatching of the communication configurations of the terminal and the first network equipment, improving the reliability of information transmission between the terminal and the first network equipment, and improving the efficiency of cell access and the working efficiency of the whole system.

Or, an access notification message is sent to the first network device based on the first communication configuration, second acknowledgement information sent by the first network device is received, and communication with the first network device is performed based on a second communication configuration.

In this way, after determining to access the target cell, the terminal does not immediately use the second communication configuration corresponding to the target cell to send the access notification message, but when the first network device uses the first communication configuration, the terminal also uses the first communication configuration to send the access notification message, and after receiving the second confirmation information sent by the first network device, the terminal again uses the second communication configuration to communicate with the first network device, and at this time, the first network device also starts to use the second communication configuration after receiving the access notification message. Therefore, the problem that information transmission is wrong due to the fact that the communication configuration of the terminal and the first network equipment is not matched when the access notification message is sent is solved, the reliability of information transmission between the terminal and the first network equipment is improved, and the cell access efficiency and the working efficiency of the whole system are improved.

In a possible implementation manner, the second communication configuration is obtained by updating the first communication configuration.

In one possible implementation, the first communication configuration and the second communication configuration include at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

In a possible implementation manner, the first network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first and second communication configurations are a master cell group, MCG, configuration; the access notification message is a Radio Resource Control (RRC) reconfiguration completion message;

the indication information corresponding to the second communication configuration is used for indicating the target primary and secondary cells switched by the terminal;

the indication information includes at least one of: the identifier of the target primary and secondary cell, the identifier of the MCG configuration information corresponding to the target primary and secondary cell, or the preamble corresponding to the target primary and secondary cell.

In the above scenario, the terminal notifies the target cell to which the main base station is to be handed over, so that the main base station can update the currently used first communication configuration to the second communication configuration, and can successfully receive the RRC reconfiguration message sent by the terminal based on the second communication configuration, thereby ensuring that the configuration used by the terminal and the configuration used by the main base station are matched.

In a possible implementation manner, when the terminal is handed over to the target cell based on a dual activation protocol stack DAPS in combination with a conditional handover CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the terminal is decreased;

the second communication configuration is used for adjusting the uplink transmission power of the terminal.

Optionally, the second communication configuration further includes parameters related to adjusting a Modulation and Coding Scheme (MCS) and a number of layers of a multiple-input multiple-output (MIMO) of the terminal.

In the above scenario, the terminal may notify the first network device of the decrease of the uplink and downlink transmission power through the indication information, so that the first network device may adjust the uplink and downlink transmission power of the terminal, and ensure normal transmission of data.

In a possible implementation manner, the first network device is a master base station, the terminal is connected to the master base station and at least one secondary base station, a first secondary base station in the at least one secondary base station triggers the terminal to switch to the target cell, and the target cell is a cell managed by the target secondary base station; the first communication configuration and the second communication configuration are Master Cell Group (MCG) configurations;

the indication information corresponding to the second communication configuration is used for indicating a target cell switched by the terminal;

the indication information is as follows: an identifier of the target cell or an identifier of an MCG configuration corresponding to the target cell.

Optionally, the MCG configuration identification may include, but is not limited to: the identifier of the target cell, the identifier of the MCG configuration information corresponding to the target cell, or the preamble corresponding to the target cell.

In the above scenario, the terminal indicates the target cell to be switched, so that the main base station can update the currently used first communication configuration to the second communication configuration, and can successfully receive the RRC reconfiguration message sent by the terminal based on the second communication configuration, thereby ensuring that the terminal matches the configuration used by the main base station.

In a possible implementation manner, in a process that the terminal determines that the handover to the target cell is completed to the terminal, the terminal sends, to the first network device, key indication information, where the key indication information is used to instruct the first network device to perform data decryption by using a key in a first communication configuration or using a key in a second communication configuration.

Through the key indication information, the terminal and the first network device can still normally transmit data in a time period with unmatched configuration.

In a possible implementation manner, the key indication information is included in a data packet sent by the terminal to the first network device;

or, the key indication information is sent to the first network device through mac ce or PDCP control information.

In one possible implementation, the MAC CE or PDCP control information indicates a key used by the terminal and a packet number encrypted using the key;

or, the MAC CE or PDCP control information indicates a key used by the terminal and a preset time period for encrypting a data packet using the key.

In a second aspect, an embodiment of the present application provides a method for accessing a cell, where the method is used for a terminal to access a target cell, and the method includes:

the method comprises the steps that a first network device receives indication information sent by a terminal based on a first communication configuration, the indication information corresponds to a second communication configuration, first confirmation information is sent to the terminal, and an access notification message sent by the terminal based on the second communication configuration is received;

or, the first network device receives an access notification message sent by the terminal based on the first communication configuration, and sends second confirmation information to the terminal, where the second confirmation information is used to trigger the terminal to communicate with the first network device based on the second communication configuration.

a key for encrypting and decrypting data;

a frequency band in which information is transmitted;

maximum transmission power when transmitting information.

In a possible implementation manner, the first network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first communication configuration and the second communication configuration are in an MCG configuration; the access notification message is an RRC reconfiguration completion message;

the indication information corresponding to the second communication configuration is used for indicating a target primary and secondary cell switched by the terminal;

In a possible implementation manner, when the terminal is handed over to the target cell based on DAPS in combination with CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the terminal is decreased;

the indication information corresponding to the second communication configuration is used for indicating the target cell switched by the terminal;

In a possible implementation manner, in a process that the terminal determines to handover to the target cell until the terminal completes handover to the target cell, the first network device sends key indication information to the terminal, where the key indication information is used to instruct the terminal to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

In a possible implementation manner, the key indication information is included in a data packet sent by the first network device to the terminal;

or, the key indication information is sent to the terminal through MAC CE or PDCP control information.

In one possible implementation, the MAC CE or PDCP control information indicates a key used by the first network device and a data packet number encrypted using the key;

or, the MAC CE or PDCP control information indicates a key used by the first network device and a preset time period for encrypting a data packet using the key.

In a third aspect, an embodiment of the present application provides a communication apparatus, which may include:

a sending unit, configured to send, to a first network device, indication information corresponding to a second communication configuration based on a first communication configuration, a receiving unit, configured to receive first acknowledgement information sent by the first network device, where the sending unit is further configured to send, to the first network device, an access notification message based on the second communication configuration;

or, the sending unit is configured to send an access notification message to the first network device based on the first communication configuration, the receiving unit is further configured to receive second acknowledgement information sent by the first network device, and the sending unit and the receiving unit are further configured to communicate with the first network device based on a second communication configuration.

a key for encrypting and decrypting data;

a frequency band in which information is transmitted;

maximum transmission power when transmitting information.

In a possible implementation manner, the first network device is a master base station, and the target cell is a target primary and secondary cell to be switched of the communication apparatus or a newly added target primary and secondary cell to be accessed; the first and second communication configurations are a master cell group, MCG, configuration; the access notification message is a Radio Resource Control (RRC) reconfiguration completion message;

the indication information corresponding to the second communication configuration is used for indicating a target primary cell and a target secondary cell switched by the communication device;

In a possible implementation manner, when the communication apparatus is handed over to the target cell based on a dual activation protocol stack DAPS in combination with a conditional handover CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the communication apparatus is decreased;

the second communication configuration is used for adjusting the uplink transmission power of the communication device.

In a possible implementation manner, the first network device is a master base station, the communication apparatus connects the master base station and at least one secondary base station, a first secondary base station in the at least one secondary base station triggers the communication apparatus to switch to the target cell, and the target cell is a cell managed by the target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

the indication information corresponding to the second communication configuration is used for indicating a target cell switched by the communication device;

In a possible implementation manner, in a process that the communication apparatus determines that the handover to the target cell is completed to the communication apparatus, the communication apparatus sends, to the first network device, key indication information for instructing the first network device to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

In a possible implementation manner, the key indication information is included in a data packet sent by the communication apparatus to the first network device;

or, the key indication information is sent to the first network device through a medium access control protocol control element MAC CE or packet data convergence protocol PDCP control information.

In one possible implementation, the MAC CE or PDCP control information indicates a key used by the communication device and a packet number encrypted using the key;

alternatively, the MAC CE or PDCP control information indicates a key used by the communication apparatus and a preset time period for ciphering a data packet using the key.

In one possible implementation, the communication device is a terminal.

In a fourth aspect, an embodiment of the present application provides a network device, which may include:

the terminal comprises a receiving unit, a sending unit and a receiving unit, wherein the receiving unit is used for receiving indication information sent by the terminal based on first communication configuration, the indication information corresponds to second communication configuration, the sending unit is used for sending first confirmation information to the terminal, and the receiving unit is also used for receiving an access notification message sent by the terminal based on the second communication configuration;

or, the receiving unit is configured to receive an access notification message sent by the terminal based on the first communication configuration, and the sending unit is configured to send second acknowledgement information to the terminal, where the second acknowledgement information is used to trigger the terminal to communicate with the network device based on the second communication configuration.

a key for encrypting and decrypting data;

a frequency band in which information is transmitted;

maximum transmission power when transmitting information.

In a possible implementation manner, the network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first communication configuration and the second communication configuration are in an MCG configuration; the access notification message is an RRC reconfiguration completion message;

In a possible implementation manner, when the terminal is handed over to the target cell based on DAPS in combination with CHO, the indication information corresponding to the second communication configuration is used to notify the network device that the uplink transmission power of the terminal is decreased;

In a possible implementation manner, the network device is a master base station, the terminal is connected to the master base station and at least one secondary base station, a first secondary base station in the at least one secondary base station triggers the terminal to switch to the target cell, and the target cell is a cell managed by the target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

the indication information is as follows: an identity of the target cell or an identity of an MCG configuration corresponding to the target cell.

In a possible implementation manner, in a process that the terminal determines to handover to the target cell until the terminal completes handover to the target cell, the sending unit is further configured to send, to the terminal, key indication information, where the key indication information is used to instruct the terminal to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

In a possible implementation manner, the key indication information is included in a data packet sent by the network device to the terminal;

In one possible implementation, the MAC CE or PDCP control information indicates a key used by the network device and a packet number encrypted using the key;

or the MAC CE or PDCP control information indicates a key used by the network device and a preset time period for encrypting a data packet using the key.

In a fifth aspect, an apparatus is provided. The apparatus provided by the present application has the functionality to implement the behavior of the terminal or network device in the above-mentioned method aspect, which comprises means (means) for performing the steps or functions described in the above-mentioned method aspect. The steps or functions may be implemented by software, or by hardware (e.g., a circuit), or by a combination of hardware and software.

In one possible design, the apparatus includes one or more processors and a communication unit. The one or more processors are configured to support the apparatus to perform the corresponding functions of the terminal in the above method. For example, whether to access a cell is determined, the instruction transmitting unit transmits instruction information corresponding to the second communication configuration to the network device based on the first communication configuration, and the like. The communication unit comprises a sending unit and a receiving unit, and is used for supporting the device to communicate with other equipment and realizing sending and/or receiving functions. For example, the indication information is sent to the first network device, the first acknowledgement information sent by the first network device is received, the access notification message is sent to the first network device, and the like.

Optionally, the apparatus may also include one or more memories for coupling with the processor that hold the necessary program instructions and/or data for the apparatus. The one or more memories may be integrated with the processor or may be separate from the processor. The present application is not limited.

The apparatus may be a smart terminal or a wearable device, and the communication unit may be a transceiver or a transceiver circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The device may also be a communication chip. The communication unit may be an input/output circuit or an interface of the communication chip.

In another possible design, the apparatus includes a transceiver, a processor, and a memory. The processor is configured to control the transceiver or the input/output circuit to transceive signals, the memory is configured to store a computer program, and the processor is configured to execute the computer program in the memory, such that the apparatus performs the method performed by the terminal in the first aspect or any one of the possible implementations of the first aspect.

In one possible design, the apparatus includes one or more processors and a communication unit. The one or more processors are configured to enable the apparatus to perform the corresponding functions of the first network device in the above method. For example, when receiving the instruction information transmitted from the terminal, the instruction transmitting unit transmits the first acknowledgement information and the like to the terminal. The communication unit is used for supporting the device to communicate with other equipment and realizing receiving and/or sending functions. For example, the indication information sent by the terminal is received, the first confirmation information is sent to the terminal, and the access notification message sent by the terminal is received.

Optionally, the apparatus may further comprise one or more memories for coupling with the processor, which stores program instructions and/or data necessary for the apparatus. The one or more memories may be integral with the processor or separate from the processor. The present application is not limited.

The apparatus may be a base station, a master base station, a gNB, a TRP, or the like, and the communication unit may be a transceiver, or a transceiver circuit. Optionally, the transceiver may also be an input/output circuit or interface.

In another possible design, the apparatus includes a transceiver, a processor, and a memory. The processor is configured to control the transceiver or the input/output circuit to transceive signals, the memory is configured to store a computer program, and the processor is configured to execute the computer program in the memory, so that the apparatus performs the method performed by the first network device in any one of the possible implementations of the second aspect or the second aspect.

In a sixth aspect, a system is provided, which includes the terminal and the first network device.

In a seventh aspect, a computer-readable storage medium is provided for storing a computer program comprising instructions for performing the method of the first aspect or any one of the possible implementations of the first aspect.

In an eighth aspect, there is provided a computer-readable storage medium for storing a computer program comprising instructions for performing the method of the second aspect or any one of the possible implementations of the second aspect.

In a ninth aspect, there is provided a computer program product comprising: computer program code for causing a computer to perform the method of the first aspect or any of the possible implementations of the first aspect when the computer program code runs on a computer.

In a tenth aspect, there is provided a computer program product comprising: computer program code for causing a computer to perform the method of any of the above second aspects and possible implementations of the second aspect when said computer program code is run on a computer.

In an eleventh aspect, there is provided a chip comprising one or more processing circuits, wherein the one or more processing circuits are configured to implement the method of the first aspect or any one of the possible implementations of the first aspect.

In a twelfth aspect, a chip is provided, which includes one or more processing circuits, wherein the one or more processing circuits are configured to implement the method in any one of the possible implementations of the second aspect and the second aspect.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the background art of the present application, the drawings required to be used in the embodiments or the background art of the present application will be described below.

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

fig. 2 is a flowchart illustrating a method for accessing a cell according to an embodiment of the present application;

fig. 3 is a flowchart illustrating another method for allocating resources according to an embodiment of the present application;

fig. 4 is a flowchart illustrating a method for accessing a cell in a CPAC scenario according to an embodiment of the present application;

fig. 5 is a schematic flowchart of a method for accessing a cell in a CPAC scenario according to an embodiment of the present application;

fig. 6 is a schematic flowchart of a method for accessing a cell in a scenario where DAPS is combined with CHO according to an embodiment of the present disclosure;

fig. 7 is a flowchart illustrating a method for accessing a cell triggered by a secondary base station in a multi-connection scenario according to an embodiment of the present application;

fig. 8 is a flowchart illustrating a method for accessing a cell in a CPAC scenario according to an embodiment of the present application;

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

fig. 10 is a schematic diagram of another communication device according to an embodiment of the present disclosure;

fig. 11 is a schematic composition diagram of a network device according to an embodiment of the present application;

fig. 12 is a schematic composition diagram of another network device according to an embodiment of the present application.

Detailed Description

Embodiments of the present application are described below with reference to the drawings in the embodiments of the present application.

The terms "including" and "having," and any variations thereof, in the description and claims of this application and the drawings described above, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Fig. 1 is a schematic diagram of a communication system according to an embodiment of the present disclosure. Among other things, a terminal 10, a first network device 20, and an optional second network device 30 may be included.

The terminal 10 is a device with a wireless transceiving function, and the terminal device can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.). The terminal may be a mobile phone (mobile phone), a tablet computer (pad), a computer device with a wireless transceiving function, a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal device in industrial control (industrial control), a wireless terminal device in self driving (self driving), a wireless terminal device in remote medical treatment (remote medical), a wireless terminal device in smart grid (smart grid), a wireless terminal device in transportation safety (transportation safety), a wireless terminal device in smart city (smart city), a wireless terminal device in smart home (smart home), and may further include a User Equipment (UE), and the like.

The first network device 20 and the second network device 30 are both network devices, and the network devices are devices in a wireless network, for example, radio Access Network (RAN) nodes that access terminal devices to the wireless network. Currently, some examples of RAN nodes are: the base station includes a gNB, a Transmission Reception Point (TRP), an evolved Node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a Base Band Unit (BBU), or a wireless fidelity (Wifi) Access Point (AP), an Integrated Access and Backhaul (IAB), etc. In one network configuration, a network device may include a Centralized Unit (CU) node, or a Distributed Unit (DU) node, or a RAN device including a CU node and a DU node. In one network architecture, the centralized unit CU nodes can be divided into a control plane (CU-CP) and a user plane (CU-UP). The CU-CP is responsible for Control plane functions, and mainly includes Radio Resource Control (RRC) and Packet Data Convergence Protocol-Control plane (PDCP-C). The PDCP-C is mainly responsible for encryption and decryption of control plane data, integrity protection, data transmission and the like. The CU-UP is responsible for user plane functions, and mainly includes a Service Data Adaptation Protocol (SDAP) and a Packet Data Convergence Protocol-user plane (PDCP-C). Wherein the SDAP is mainly responsible for processing data of a core network and mapping flow to a bearer. The PDCP-U is mainly responsible for encryption and decryption of a data plane, integrity protection, header compression, serial number maintenance, data transmission and the like. Wherein the CU-CP and CU-UP are connected via the E1 interface. The CU-CP represents the CU connected to the core network via the Ng interface. Via F1-C (control plane) and DU connections. The CU-UP is connected via F1-U (user plane) and DU. Of course, there is also a possible implementation where PDCP-C is also in CU-UP.

In the embodiment of the present application, the terminal 10 may access another cell due to a change in location or a change in channel quality of an originally accessed cell. The present application relates to different procedures for a terminal to access a cell in different communication scenarios, and will be described below.

In a Multi-Radio-dual-connection (MR-DC) scenario, a terminal may communicate with multiple base stations, where the multiple base stations include a master base station (MN) and an activated secondary base Station (SN), and a control plane connection is established between the master base station and a core network; and the data plane connection can be established between the main base station and the core network and/or between the auxiliary base station and the core network. The communication systems of the primary base station and the secondary base station may be the same or different, for example, the primary base station is an eNB and the secondary base station is a gNB, or both the primary base station and the secondary base station are a gNB. MR-DC may be referred to simply as DC. DC may also be understood as belonging to a type of multi-connection (MC) in the context of which a terminal may access a main base station and at least one secondary base station, that is, in addition to the above-mentioned DC context, a terminal may access a main base station and two or more secondary base stations.

In a DC scenario, the primary base station manages one primary cell and the secondary base station manages one primary and secondary cell. When the terminal needs to switch the primary and secondary cells or access to a new primary and secondary cell, a conditional primary and secondary cell (PSCell) addition and change (CPAC) process may be triggered, so as to achieve the purpose that the terminal accesses to the new primary and secondary cell. The network side (such as a main base station or a secondary base station) configures a plurality of candidate pscells in advance, the network side notifies the terminal of the configuration of the candidate pscells and the corresponding increasing or changing conditions of each candidate PSCell, and then when the terminal judges that the conditions are met, the terminal directly accesses the candidate pscells meeting the conditions. By adopting the CPAC, it is not necessary to send a new PSCell configuration to the terminal after the terminal reports the measurement report, so that it is possible to shorten the time delay required for increasing or changing the PSCell, and in addition, for a scenario where the secondary base station touches the PCell to change, it is avoided that the measurement report cannot be reported and a reconfiguration message cannot be sent through a Signaling Radio Bearer (SRB) 3 when the signal quality of the PSCell changes rapidly, so that the robustness of PSCell change is improved.

In the MC scenario, a terminal may connect to a main base station and at least two secondary base stations, a network side (e.g., the main base station or the secondary base stations) may configure multiple candidate secondary base stations, and send the candidate secondary base stations to the terminal through the main base station, but the terminal does not determine whether to trigger a change of the secondary base station but waits for indication information of the network side, and when the terminal receives a request from the network side to access or switch to a candidate secondary base station, the main base station or the secondary base station may trigger the terminal to access or switch the secondary base station to implement access or switch of a target cell. The change of the auxiliary base station comprises the addition and the switching of the auxiliary base station, the addition of the auxiliary base station indicates that the terminal accesses a new auxiliary base station, and after the access, the number of the base stations accessed by the terminal is increased by 1; the switching of the secondary base stations means that the terminal is switched from one secondary base station to another secondary base station, and the number of base stations accessed by the terminal is not changed after the switching.

In the switching process in a single connection scene, a switching mode of a Dual Active Protocol Stack (DAPS for short) is provided, and the requirement of 0ms mobile interrupt delay can be met (the uplink and the downlink are required to be interrupted for 0ms or close to 0 ms). The switching mode comprises the following steps: after the source cell sends the switching message to the terminal, the data can be forwarded with the target cell. In the switching process, the data transmission between the source cell and the terminal is not interrupted, and the target cell and the source cell can both send downlink data to the terminal, so that the interruption time of the data transmission is shortened. After the terminal finishes the access in the target cell and before receiving a release message which is sent by the target cell and used for releasing the connection between the terminal and the source cell, the terminal continues to perform data transmission (including uplink and/or downlink data transmission) with the source cell; and when the terminal receives a release message which is sent by the target cell and used for releasing the connection between the terminal and the source cell, the terminal releases the connection between the terminal and the source cell. The target cell sends a switching success message to inform the completion of the switching of the source cell; and after receiving the switching success message, the source cell stops the uplink/downlink data transmission between the source cell and the terminal and sends the last data transmission serial number to the target cell.

In addition, in a Conditional Handover (CHO) process, when a source link quality is good, a source cell sends CHO configuration information to a terminal, where the CHO configuration information may include a CHO trigger condition and information of one or more candidate cells, where the information of the candidate cells may include a Cell Global Identifier (CGI) of the candidate cell, or a Physical Cell Identifier (PCI) of the candidate cell and frequency information corresponding to the candidate cell. After receiving the CHO configuration information, the terminal judges whether the candidate cell meets the CHO triggering condition according to the CHO configuration information, and takes a certain candidate cell meeting the CHO triggering condition as a target cell. Then, the terminal performs a random access process with the determined target cell, and when the random access is successfully completed, the terminal sends an RRC message (such as an RRC reconfiguration complete message) to the target cell to notify the target cell of the completion of conditional handover. The triggering of the CHO is terminal dependent and the source cell is unaware between the CHO initiating the handover to the handover success.

By combining the above DAPS and CHO, the terminal can implement cell handover with low or even zero delay according to the triggering condition configured by CHO.

Referring to fig. 1, for example, in a scenario where the terminal 10 originally accesses a cell managed by the first network device 20, in combination with a CHO, when a trigger condition of the CHO is satisfied, the terminal may switch to a cell managed by the second network device 30 or switch to another cell managed by the first network device 20 according to the trigger condition; for another example, in a DC scenario, the first network device 20 is a primary base station, the second network device 30 may be a newly added secondary base station or a secondary base station to which the terminal has currently accessed, and when a CPAC trigger condition is met, the terminal may access a primary and secondary cell managed by the newly added second network device 20 or be switched to another secondary base station, such as a primary and secondary cell managed by a third network device (not shown in fig. 1); for another example, in the MC scenario, when the second network device 20 serves as a secondary base station to instruct the terminal 10 to perform cell handover, the terminal 10 may handover to a cell managed by another secondary base station, such as a third network device (not shown in fig. 1), or access a cell managed by another newly added secondary base station, such as the third network device. However, in these procedures, there may be a problem that the communication configuration between the terminal 10 and the first network device 20 is not matched, resulting in an error in information transmission therebetween. Therefore, a method is needed to improve the reliability of information transmission. The method for accessing the cell will be described in detail below.

Referring to fig. 2, fig. 2 is a flowchart illustrating a method for accessing a cell according to an embodiment of the present application, where the method may be executed by a terminal or a device for the terminal, such as a chip, and the method is described as being executed by the terminal.

The method comprises the following steps:

s201, the terminal determines an access target cell.

Optionally, accessing the target cell includes performing cell switching in a single connection scenario, a dual connection scenario, and a multi-connection scenario, and also includes accessing a newly added cell in the current communication system in the single connection scenario, the dual connection scenario, and the multi-connection scenario, for example, in a CPAC flow in the dual connection scenario or the multi-connection scenario, the adding and switching of the PSCell are included.

Alternatively, the terminal determines that the access target cell may be sent by the first network device, such as the base station, the cell handover condition and the information of each alternative target cell to the terminal. When the terminal detects that the condition of cell switching is met, the terminal can determine a target cell to be switched to; for example, in a dual connectivity scenario, the terminal may trigger access to the target cell according to a trigger condition of the CPAC; for another example, in a scenario where DAPS is combined with CHO, the terminal may trigger access to the target cell according to a triggering condition of CHO.

Or, the first network device or another network device may instruct the terminal to perform handover, and at this time, the terminal receives handover instruction information for handover to the target cell, so as to determine to handover to the target cell. For example, in a multi-connection scenario, handover indication information may be sent by the primary base station or the secondary base station to the terminal, instructing the terminal to handover to the target cell.

S202, the terminal sends indication information corresponding to the second communication configuration to the first network equipment based on the first communication configuration.

Alternatively, the indication information may be a message or a signaling.

The indication information may indicate a target cell to which the terminal is to access, and may also indicate a communication configuration to be updated by the terminal. The correspondence relationship between the indication information and the second communication configuration may include: the indication information indicates the target cell, and the target cell adopts the second communication configuration. The first network device may determine which target cell is after receiving the indication information, and then determine the second communication configuration corresponding to the target cell. Alternatively, the correspondence between the indication information and the second communication configuration may include: the indication information indicates a communication configuration identifier, and the communication configuration identifier indicates a second communication configuration, that is, the terminal may notify the first network device which communication configuration the first network device is to update to, and the first network device determines a target cell to which the terminal is to switch and a corresponding second communication configuration according to the identifier of the communication configuration. Or, in a scenario in which the DAPS is combined with the CHO, since the terminal may have information transmission with the source cell and the target cell at the same time during the handover process, the indication information may indicate the target cell to be handed over by the terminal or notify the source cell to adjust the uplink transmit power of the terminal, and optionally, may also notify the source cell of the reduced uplink transmit power of the terminal, the MCS, or the number of MIMO layers, and the like. After receiving the indication information, the base station to which the source cell belongs can update the first communication configuration to the second communication configuration according to the indication information, and the second communication configuration is determined according to the content carried in the indication information, so that the first communication configuration and the second communication configuration have a corresponding relationship.

The first communication configuration is the communication configuration used by the terminal before the terminal determines to access the target cell, and the communication configuration is the same as the communication configuration used by the first network equipment. The first communication configuration includes one or more configuration parameters for communication between the terminal and the first network device, such as a key, a frequency band for transmitting information, a maximum transmission power when transmitting information, and the like. Optionally, scheduling related parameters such as MCS, MIMO layer number, etc. may also be included. The configuration parameter type included in the second communication configuration is similar to that of the first communication configuration, and is not described in detail.

The secret key is used for encrypting and decrypting transmitted data by the two devices; the frequency band for sending the information is used for providing frequency spectrum resources for information transmission between the terminal and the first network equipment, so that the communication between the terminal and the first network equipment is not interfered by signals of other frequency bands; the maximum transmission power when sending the information is used for adjusting the sending power of the terminal side when sending the information in an uplink way; the MCS is used for configuring a modulation and coding scheme during information transmission between the terminal and the first network equipment; the MIMO layer number is used for configuring the multiple-input multiple-output layer number during information transmission between the terminal and the first network equipment, and the frequency spectrum utilization rate is improved.

After determining to perform cell handover, the terminal generally uses a second communication configuration corresponding to the target cell immediately, where the second communication configuration is usually different from the first communication configuration, that is, the above parameters include at least one of a secret key, a frequency band of transmitted information, and a maximum transmission power when transmitting information. Resulting in a communication configuration mismatch between the terminal and the first network device. In the embodiment of the application, after determining to access the target cell, the terminal sends the indication information corresponding to the second communication configuration to the first network device by using the first communication configuration, and notifies the first network device of the target cell to be accessed by the terminal. Thus, after receiving the indication information, the first network device may determine the second communication configuration corresponding to the target cell and use the second communication configuration after receiving the indication information. Therefore, in the process of cell access, the terminal and the first network equipment both use the second communication configuration to communicate until the cell access is completed.

S203, the terminal receives the first confirmation information sent by the first network equipment.

The first acknowledgement information is used to inform the terminal that the base station has received the indication information.

The first acknowledgement information may be an acknowledgement (confirm) message or a response (response) message or an acknowledgement (ack) message, etc.

And S204, the terminal sends an access notification message to the first network equipment based on the second communication configuration.

After receiving the first acknowledgement message of the first network device, the terminal may start sending an access notification message to the first network device using the second communication configuration. At this time, since the first network device has already started the use of the second communication configuration, the first network device can normally receive the information transmitted by the terminal.

Optionally, after step S204, the terminal communicates with the first network device based on the second communication configuration.

Wherein the second communication configuration is obtained by updating the first communication configuration.

When the terminal or the second network device wants to update the first communication configuration to the second communication configuration, the second communication configuration may be directly activated and used, or parameters in the first communication configuration may be modified, for example, the maximum transmission power when sending information is modified, and then the modified parameters are activated, so as to complete the process of updating the first communication configuration to the second communication configuration.

In the embodiment of the application, when the first network device uses the first communication configuration, the terminal also uses the first communication configuration to send an indication message to notify the first network device of a cell to be accessed, so that the first network device can determine the second communication configuration matched with the target cell, in a subsequent process of cell access, the terminal and the first network device can both use the second communication configuration to carry out communication, and the problem of information transmission error caused by mismatching of the communication configurations of the terminal and the first network device is solved, the reliability of information transmission between the terminal and the first network device is improved, and the efficiency of cell access and the working efficiency of the whole system are improved.

Referring to fig. 3, fig. 3 is a schematic flowchart of another method for accessing a cell according to an embodiment of the present application; the method specifically comprises the following steps:

s301, the terminal determines an access target cell.

S302, the terminal sends an access notification message to the first network equipment based on the first communication configuration.

After determining to access the target cell, the terminal typically uses the second communication configuration corresponding to the target cell directly. While the first network device is still using the first communication configuration, resulting in a mismatch between the communication configurations of the two. In this embodiment, after determining to access the target cell, the terminal may not use the second communication configuration first, but continue to use the first communication configuration to send the access notification message to the first network device. In this way, the first network device can still receive the information transmitted by the terminal normally using the first communication configuration.

And S303, the terminal receives second confirmation information sent by the first network equipment.

The second acknowledgement information is used to inform the terminal that the first network device already knows that the terminal is to access another cell. The first network device may also begin using the second communication configuration at this time.

S304, the terminal communicates with the first network equipment based on the second communication configuration.

After receiving the second confirmation information of the first network device, the terminal may switch or update the first communication configuration currently used or directly use the second communication configuration to communicate with the first network device.

In the embodiment of the application, after determining to access the target cell, the terminal does not immediately use the second communication configuration corresponding to the target cell to send the access notification message, but when the first network device uses the first communication configuration, the terminal also uses the first communication configuration to send the access notification message, and after receiving the second confirmation information sent by the first network device, the terminal uses the second communication configuration to communicate with the first network device, and at this time, the first network device also starts to use the second communication configuration after receiving the access notification message. Therefore, the problem that information transmission is wrong due to the fact that the communication configuration of the terminal and the first network equipment is not matched when the access notification message is sent is solved, the reliability of information transmission between the terminal and the first network equipment is improved, and the cell access efficiency and the working efficiency of the whole system are improved.

On the basis of the embodiments shown in fig. 2 to fig. 3, the method for accessing a cell in the present application will be described in detail below with reference to specific scenarios from the perspective of information interaction between a terminal and a first network device through the embodiments shown in fig. 4 to fig. 8.

Please refer to fig. 4, fig. 4 is a schematic flowchart of a method for accessing a cell in a CPAC scenario according to an embodiment of the present application;

in a CPAC scenario, the first network device shown in fig. 2 is a master base station, the target cell is a target master-slave cell to which the terminal is to be switched or a newly added target master-slave cell to be accessed, the target cell is a cell managed by a slave base station, the first communication configuration and the second communication configuration are MCG configurations, and in a process of accessing the terminal to the target master-slave cell, a problem that the MCG configurations between the terminal and the master base station are not matched exists. The method for accessing a cell provided by the present application will be described below with reference to the embodiment shown in fig. 2 in a CPAC scenario. The method comprises the following steps:

s401, the primary base station sends a secondary base station addition request (SN addition request) to the first secondary base station.

S402, the main base station receives a secondary base station increase request response (SN addition request ack) sent by the first secondary base station.

And S403, the main base station sends a secondary base station adding request to the second secondary base station.

And S404, the main base station receives a secondary base station increase request response sent by the second secondary base station.

It should be noted that, in the scenario of multi-connection, the number of secondary base stations may be greater than one, and when the number of secondary base stations is greater than one, the primary base station may send the request in step S401 to each secondary base station and receive the response of each secondary base station. For ease of description, only two secondary base stations are shown in fig. 4.

The primary base station adds the request by transmitting a secondary base station addition request to one or more secondary base stations. The secondary base stations may be requested to acquire information of the CPAC, such as a trigger condition of the CPAC corresponding to each secondary base station, a communication configuration of the primary and secondary cells, such as an MCG configuration and an SCG configuration corresponding to the primary and secondary cells, and the like.

S405, the terminal receives an RRC Reconfiguration (RRC Reconfiguration) message transmitted by the main base station. The RRC reconfiguration message includes the trigger conditions of the CPACs corresponding to the secondary base stations and the communication configuration of the primary and secondary cells.

And S406, the terminal detects that the triggering condition of the CPAC corresponding to the first auxiliary base station is met. Thus, the terminal can determine that the target cell to be accessed is the target primary and secondary cell managed by the first secondary base station.

This step may refer to step S201 in fig. 2.

In this embodiment, the terminal switches the cell managed by the first secondary base station to be the primary and secondary cell or the target primary and secondary cell managed by the first secondary base station from the source primary and secondary cell.

And if the terminal is switched to the target main and auxiliary cells managed by the first auxiliary base station, the terminal is disconnected with the source main and auxiliary cells.

And S407, the terminal sends indication information to the main base station based on the first communication configuration.

This step may be referred to as step S202 in fig. 2.

The indication information is used for indicating the target main and auxiliary cells added by the terminal or to be switched to be main and auxiliary cells managed by the first auxiliary base station. When the terminal belongs to the added main and auxiliary cells, the first communication configuration is the MCG configuration correspondingly used by the main base station when the terminal is in a single connection state; when belonging to the handover primary and secondary cell, the first communication configuration is an MCG configuration corresponding to the source primary and secondary cell. Optionally, the first communication configuration may further include an SCG configuration, and the kind of parameters included in the SCG configuration is similar to that of the MCG, which is not described herein again.

Since the MCG configuration corresponding to the target primary and secondary cell is already known by the main base station in the process of steps S401 to S404, the main base station can determine to use the MCG configuration corresponding to the target primary and secondary cell when the terminal transmits the indication information to the main base station.

The MCG configuration may include, but is not limited to, a key for encrypting and decrypting data, a frequency band for transmitting information, a maximum transmission power when transmitting information, an MCS, a number of MIMO layers, and the like.

Optionally, the indication information includes at least one of: the identifier of the target primary and secondary cell, the identifier of the MCG configuration information corresponding to the target primary and secondary cell, or the preamble corresponding to the target primary and secondary cell.

The transmission mode of the indication information may be as follows:

the first method is as follows: the terminal may send an RRC message to the primary base station indicating that a condition triggering addition of a PSCell is satisfied and indicating which PSCell is (e.g., an identifier of the target primary and secondary cell, or an identifier of MCG configuration information corresponding to the target primary and secondary cell). Optionally, the RRC layer may also notify the PHY or MAC CE to send the indication message, which is faster in the process.

The second method comprises the following steps: the terminal may initiate a Random Access Channel (RACH) process to the master base station, and the master base station configures different preamble codes for different pscells. Then, the main base station can judge the PSCell to be switched by the terminal through the RACH resource used by the terminal to initiate RACH. It should be noted that the mapping relationship between the PSCell and the preamble may be configured for the terminal in S405, and then the terminal only needs to send a preamble to the master base station. The RACH procedure may be triggered by the MAC layer or the RRC layer, which is not limited herein.

And S408, the main base station sends first confirmation information to the terminal.

This step may refer to step S203 in fig. 2.

For example, for the first mode, the main base station may reply to the terminal with an RRC acknowledgement message, or reply with an acknowledgement message through a PHY or MAC layer. For the second mode, the primary base station may reply to the terminal with a random access response message or may also reply with an acknowledgement message. The embodiments of the present application are not limited in any way.

And S409, switching or updating the main base station into or directly using the second communication configuration. The second communication configuration is an MCG configuration corresponding to the target primary and secondary cell. Optionally, the second communication configuration may also be an SCG configuration.

And S410, the terminal is switched to or updated to or directly uses the second communication configuration.

And S411, the terminal sends an RRC reconfiguration completion message to the main base station based on the second communication configuration. This step corresponds to step S204 in fig. 2. The RRC reconfiguration complete message comprises an SNRRC reconfiguration complete message used for informing the first auxiliary base station by the terminal.

In this step, since both the terminal and the main base station use the second communication configuration at this time, there is no problem that the MCGs do not match.

And S412, the main base station sends the SNRRC reconfiguration completion message to the first auxiliary base station.

After step S412, there is no longer a problem of mismatch in MCG configuration between the main base station and the terminal in both sending and receiving signaling and data transmission.

Please refer to fig. 5, fig. 5 is a schematic flowchart of another method for accessing a cell in a CPAC scenario provided in the embodiment of the present application; in this scenario, the first network device shown in fig. 3 is a primary base station, the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed, the target cell is a cell managed by a secondary base station, and the first communication configuration and the second communication configuration are MCG configurations. In the following, the method for accessing a cell provided by the present application will be described with reference to the embodiment shown in fig. 3 in a CPAC scenario, where steps S501 to S506 are the same as steps S401 to S406 in fig. 4, and are not described herein again, and after step S506, the method further includes the following steps:

s507, the terminal keeps using a first communication configuration, and when the terminal belongs to the added main and auxiliary cells, the first communication configuration is an MCG configuration correspondingly used by the main base station when the terminal is in a single connection state; when belonging to the handover primary and secondary cell, the first communication configuration is an MCG configuration corresponding to the source primary and secondary cell. Optionally, the first communication configuration may also include an SCG configuration.

And S508, the terminal sends an RRC reconfiguration completion message to the main base station based on the first communication configuration. This step corresponds to step S302 in fig. 3. The RRC reconfiguration complete message includes a SN RRC reconfiguration complete message used by the terminal to notify the first secondary base station.

And S509, the main base station sends a SN RRC reconfiguration completion message to the first auxiliary base station to inform the first auxiliary base station that the terminal is to be accessed into the main and auxiliary cells of the first auxiliary base station.

S510, the terminal is switched to or updated to or directly uses the second communication configuration. The second communication configuration is an MCG configuration corresponding to the target primary and secondary cell. Optionally, the second communication configuration may also include an SCG configuration.

And S511, the terminal and the first auxiliary base station complete the switching of the target main and auxiliary cells.

For a specific process of switching to the primary and secondary cells, details are not repeated in this application, and for example, reference may be made to any implementation manner described in the 3GPP communication protocol.

S512, the main base station is switched to or updated to or directly uses the second communication configuration.

That is, after the terminal and the target primary and secondary cells complete the process of adding or switching the primary and secondary cells, the primary base station may update the corresponding MCG configuration according to the switched primary and secondary cells.

In another possible implementation manner, the process of step S512 may also be executed after step S508, and the embodiment of the present application is not limited in any way.

Referring to fig. 6, fig. 6 is a schematic flowchart illustrating a method for accessing a cell in a scenario where DAPS is combined with CHO according to an embodiment of the present disclosure;

in the scenario of combining DAPS with CHO, although 0ms handover of CHO can be guaranteed, since the terminal will perform data transmission with the source cell and the target cell simultaneously in the process of handing over the cells, due to the limitation of the terminal capability, the power corresponding to each cell will be reduced, which may result in the reduction of the uplink transmission capability of the terminal. Since the source cell is not aware during the handover, the source cell does not know that the terminal has reduced its transmit power, which may result in a large number of data transmission errors if the source cell also lets the terminal transmit a lot of data during this process. Therefore, in this scenario, the method for accessing a cell as described in the embodiment shown in fig. 2 or fig. 3 in this application may be used, and since a base station may manage multiple cells, a source cell and a target cell may belong to the same base station for management, or may belong to different base stations for management. The method for accessing a cell provided in the present application will be described below with reference to the embodiment shown in fig. 2 in a scenario where DAPS is combined with CHO. The method comprises the following steps:

s601, the source base station sends a handover request (HO request) to the first target base station.

S602, the first target base station sends a handover request acknowledgement (HO request ack) to the source base station.

S603, the source base station sends a switching request to the second target base station.

And S604, the second target base station sends a switching request response to the source base station.

It should be noted that the number of the target base stations may be one or more, and when the number of the target base stations is greater than one, the source base station may send the request in step S601 to each target base station and receive the response of each target base station. For convenience of description, only two target base stations are shown in fig. 6.

The source base station sends a handover request to one or more target base stations. The target base stations may be requested to acquire CHO information, such as a CHO trigger condition corresponding to each target base station, a communication configuration of the target cell, such as an uplink transmission power corresponding to the target cell.

S605, the terminal receives the configuration message of the combination of the DAPS and the CHO sent by the source base station. The configuration message includes the triggering conditions of the CHO and the communication configuration of the target cell corresponding to the target base stations.

S606, the terminal detects that the triggering condition of the CHO corresponding to the first target base station is met. Thus, the terminal determines that the target cell to be accessed is the target cell managed by the first target base station.

This step may refer to step S201 in fig. 2.

In this embodiment, handover is to be made to the target cell managed by the first target base station.

And S607, the terminal sends indication information to the source base station based on the first communication configuration. This step corresponds to step S203 in fig. 2. The first communication configuration is a communication configuration used when the terminal does not initiate cell switching and only has data transmission with the source base station, and includes maximum transmission power when information is transmitted, and may also include parameters related to scheduling such as MCS or MIMO layer number. The indication information is used for informing the source base station that the uplink transmission power of the terminal is reduced. Optionally, the indication information may also indicate an amplitude of uplink power reduction of the terminal or a current maximum uplink transmission power of the terminal.

And S608, the source base station sends first confirmation information to the terminal.

This step may refer to step S203 in fig. 2.

Optionally, the adjusting, by the source base station, the first communication configuration to the second communication configuration according to the indication information includes: the uplink transmit power of the terminal is adjusted according to the condition that the uplink transmit power is decreased, and optionally, the source base station may also adjust parameters related to scheduling, such as MCS, MIMO layer number, and the like, and the number of data transmissions.

If the source base station adjusts the uplink transmission power only according to the variation of the uplink transmission power of the terminal, the terminal side may not adjust the communication configuration and may transmit information according to its current capability.

And S609, in the process of switching the target cell between the terminal and the target base station, the terminal keeps connected with the source base station.

For a specific handover process, reference may be made to any implementation manner described in the existing protocol, and details are not described here.

Specifically, from the start to the completion of the handover procedure, the terminal always maintains the connection with the source base station, that is, the terminal does not disconnect from the source base station until the terminal is handed over to the target cell.

It should be noted that, in a single scenario of CHO, the source base station is not usually notified by the triggering terminal of CHO. If the source base station needs to be notified in the scenario of DAPS combined with CHO, the terminal may send the access notification message using the first communication configuration and then switch or update the first communication configuration to the second communication configuration, so that the terminal communicates with the primary base station through the second communication configuration, with reference to the method in the embodiment shown in fig. 5. And will not be described in detail herein.

Referring to fig. 7, fig. 7 is a flowchart illustrating a method for accessing a cell triggered by a secondary base station in a multi-connection scenario according to an embodiment of the present disclosure. In a multi-connection scenario, a network side (e.g., a master base station or a secondary base station) may configure multiple candidate secondary base stations, and send the multiple candidate secondary base stations to a terminal through the master base station, but the terminal does not determine whether to trigger a change of the secondary base station, but waits for indication information of the network side (e.g., the master base station or the secondary base station), and when the terminal receives an indication that the network side adds or switches to a candidate secondary base station, the terminal immediately updates the MCG configuration and the SCG configuration corresponding to the secondary base station. The switching indication information of the network side can be transmitted by the main base station or the auxiliary base station. When a first secondary base station in at least one secondary base station connected with a terminal triggers the terminal to switch to a target cell, the main base station does not know that the terminal has switched and the MCG configuration changes, so that the problem that the MCG configuration is not matched between the main base station and the terminal exists. The method for accessing a cell provided by the present application will be described below with reference to the embodiment shown in fig. 2 in a scenario where the secondary base station changes triggered by the secondary base station. The method comprises the following steps:

and S701, the main base station sends a secondary base station increasing request to the target secondary base station.

And S702, the target auxiliary base station sends an auxiliary base station increase request response to the main base station.

It should be noted that the number of the target secondary base stations may be one or more, and when the number of the target secondary base stations is greater than one, the main base station may send the request in step S701 to each target secondary base station and receive a response of each target secondary base station. For convenience of description, only one target secondary base station is shown in fig. 7.

The primary base station sends a secondary base station addition request to one or more target secondary base stations. The target secondary base stations may be requested to acquire a communication configuration of the target cell managed by each target base station, for example, a communication configuration corresponding to the target cell, such as an MCG configuration, an SCG configuration, and the like.

And S703, the terminal receives the RRC reconfiguration message sent by the main base station. The RRC reconfiguration message includes communication configurations of target cells corresponding to the target secondary base stations.

And S704, the terminal receives a switching instruction sent by the source secondary base station. Thus, the terminal may determine a target cell to access.

This step may refer to step S201 in fig. 2.

Alternatively, the handover indication may be sent by other secondary base stations.

S705, the terminal sends indication information to the main base station based on the first communication configuration.

This step may be referred to as step S202 in fig. 2.

The indication information is used for indicating the target cell switched by the terminal.

For description of the first communication configuration, reference is made to the description in the embodiment shown in fig. 4, and details are not repeated here.

And S706, the main base station sends first confirmation information to the terminal.

This step may refer to step S203 in fig. 2.

S707, the primary base station switches or updates to or directly uses the second communication configuration. The second communication configuration is an MCG configuration corresponding to the target cell. Optionally, the second communication configuration may also include an SCG configuration.

And S708, the terminal is switched to or updated to or directly uses the second communication configuration.

And S709, the terminal and the target auxiliary base station complete the switching process.

For a specific process of handover to a target secondary base station, details are not repeated in this application, and for example, reference may be made to any implementation manner described in a 3GPP communication protocol.

And S710, the terminal sends a switching success message to the main base station based on the second communication configuration. The message may be an RRC reconfiguration complete message or other messages, which is not limited in this embodiment.

It should be noted that, in a scenario of dual connectivity or multiple connectivity, if the method for accessing a cell described in conjunction with fig. 3 is required to complete cell handover, corresponding to step S302, if the terminal needs to send an access notification message to the primary base station, referring to the methods in the embodiments shown in fig. 3 and 5, the terminal first sends the access notification message using the first communication configuration, after the terminal completes handover with the target secondary base station, and after step S303 in fig. 3, the terminal switches or updates the first communication configuration to or directly uses the second communication configuration, and then the terminal communicates with the primary base station through the second communication configuration. And will not be described in detail herein.

In addition, in the user plane, since the module for packet ciphering is located at the primary base station in the terminal single-connection state, while in the terminal double-connection or multi-connection state, the module for ciphering, i.e., the PDCP entity, may change from the primary base station to the secondary base station, and vice versa. Therefore, the primary base station transmits data using the old key, but the secondary base station receives data using the new key, so that the terminal cannot normally receive data until the primary base station updates the key configuration. To solve the problem, please refer to fig. 8, where fig. 8 is a flowchart illustrating a method for cell access in a CPAC scenario according to an embodiment of the present application. The method may comprise the steps of:

s801, the terminal determines that the CPAC triggering condition is met.

S802, the terminal sends key indication information to the main base station, wherein the key indication information is used for indicating the main base station to use a key in the first communication configuration or use a key in the second communication configuration for data decryption.

Correspondingly, on the master base station side, the master base station may also send the key indication information to the terminal in the process of sending the RRC reconfiguration message to the terminal to receive the RRC reconfiguration complete message sent by the terminal.

When the terminal belongs to the added main and auxiliary cells, the first communication configuration is the MCG configuration correspondingly used by the main base station when the terminal is in a single connection state; when belonging to the handover primary and secondary cell, the first communication configuration is an MCG configuration corresponding to the source primary and secondary cell. The second communication configuration is an MCG configuration corresponding to a target primary and secondary cell.

And S803, after the terminal and the main base station both use the second communication configuration, stopping sending the key indication information.

Optionally, the key indication information is included in a data packet sent by the terminal to the first network device;

or, the key indication information is sent to the first network device through medium access MAC CE or PDCP control information.

Optionally, the MAC CE or PDCP control information indicates a key used by the terminal and a packet number encrypted using the key;

For the two modes, the sending end device (here, the uplink, the terminal is the sending end device, and the main base station is the sending end device in the downlink) needs to determine the data packet number or a preset time period for prediction, and any one of the two modes can be selected according to the prediction capability of the sending end device. Estimating the packet number requires a higher capacity, but in the case of transmission delay, using the packet number for indication can achieve a better transmission effect. The preset time period is used for indicating the lower requirement on the capability of the terminal, and the method is suitable for being used by a plurality of devices.

The key indication information may be a specific key or an identifier, for example, 0 may represent using the key in the first communication configuration, and 1 may represent using the key in the second communication configuration.

It should be noted that, the above-mentioned manner of key indication may be used in the existing CPAC procedure, or may be used in conjunction with the method for cell access in the embodiment of the present application, please refer to fig. 4 and 8, in the embodiment shown in fig. 4, for the main base station to receive uplink data, after the terminal confirms that the main base station has received the indication information and updated the MCG configuration corresponding to the candidate PSCe l, that is, step S409, because the main base station has updated the MCG configuration, the terminal has not completed updating the MCG configuration, in this process, the terminal may add the key indication information to the transmission data packet between step S409 and step S410. Since the time period in which the key of the terminal and the key of the master base station do not match is between S409 and S410 in fig. 4, the time period is relatively short, and therefore, the time period in which the key indication information is transmitted may include this time period. Alternatively, the key indication information may be transmitted through the MAC CE or PDCP control information after step S406.

For the terminal to receive downlink data, the communication configurations of the terminal and the master base station are the same after step S410 in fig. 4, but after step S406 and before the master base station updates the second communication configuration in step S409, the master base station has sent some data packets, which are encrypted by using the key in the first communication configuration, so that the data packets received by the terminal are not known to be encrypted by using the key in the first communication configuration or the key in the second communication configuration. Therefore, the header of the data packet sent after the main base station updates the second communication configuration can carry a key indication message, so that the terminal knows which key to decrypt when receiving the data packets. Alternatively, the key indication information may be transmitted through the MAC CE or PDCP control information after step S406.

Of course, it is also possible to decrypt using the key of the second communication configuration with the key indication by default, and decrypt using the key of the first communication configuration without carrying the key indication.

Referring to fig. 5 and 8 together, from S510-S512 in fig. 5, that is, during the period from the terminal updating the MCG configuration to the main base station updating the MCG configuration, there is a phenomenon that the MCG between the terminal and the main base station does not match for a while, so that the key indication information can be carried in the uplink and downlink data transmission during S510-S512 in fig. 5. Since this time is longer than the time of S409-S410 in fig. 4, the gain obtained by using the key indication is larger, because if the user plane data packets sent during S510-S512 in fig. 5 are not successfully received without carrying the key indication information, air interface resources in this time are wasted.

By the key indication method in the embodiment of the application, the receiving end can successfully receive data, so that air interface resources are saved, and the efficiency and the success rate of data transmission are improved.

Referring to fig. 9, fig. 9 is a schematic diagram illustrating a communication device according to an embodiment of the present disclosure; can include the following steps:

a sending unit 100, configured to send, to a first network device, indication information corresponding to a second communication configuration based on a first communication configuration, a receiving unit 200, configured to receive first acknowledgement information sent by the first network device, where the sending unit 100 is further configured to send an access notification message to the first network device based on the second communication configuration;

or, the sending unit 100 is configured to send an access notification message to the first network device based on the first communication configuration, the receiving unit 200 is configured to receive second acknowledgement information sent by the first network device, and the sending unit 100 and the receiving unit 200 are further configured to communicate with the first network device based on a second communication configuration.

Optionally, the second communication configuration is obtained by updating the first communication configuration.

Optionally, the first communication configuration and the second communication configuration comprise at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

Optionally, the first network device is a master base station, and the target cell is a target master-slave cell to be switched by the communication apparatus or a newly added target master-slave cell to be accessed; the first and second communication configurations are a master cell group, MCG, configuration; the access notification message is a Radio Resource Control (RRC) reconfiguration completion message;

the indication information corresponding to the second communication configuration is used for indicating a target primary and secondary cell switched by the communication device;

Optionally, when the communication apparatus is handed over to the target cell based on a dual activation protocol stack DAPS in conjunction with a conditional handover CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the communication apparatus is decreased;

Optionally, the first network device is a master base station, the communication apparatus is connected to the master base station and at least one secondary base station, a first secondary base station in the at least one secondary base station triggers the communication apparatus to switch to the target cell, and the target cell is a cell managed by the target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

Optionally, in a process that the communication apparatus determines to handover to the target cell until the communication apparatus completes handover to the target cell, the communication apparatus sends, to the first network device, key indication information for instructing the first network device to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

Optionally, the key indication information is included in a data packet sent by the communication apparatus to the first network device;

Optionally, the MAC CE or PDCP control information indicates a key used by the communication device and a packet number encrypted using the key;

alternatively, the MAC CE or PDCP control information indicates a key used by the communication apparatus and a preset time period for encrypting a data packet using the key.

Optionally, the communication device is a terminal.

For the concepts, explanations, details and other steps related to the technical solutions provided in the embodiments of the present application related to the communication device, please refer to the description of the content of the terminal in the foregoing method or other embodiments, which is not described herein again.

Please refer to fig. 10, which is a schematic diagram illustrating another communication device according to an embodiment of the present disclosure; may include a processor 110, a memory 120, and a bus 130. The processor 110 and the memory 120 are connected by a bus 130, the memory 120 is used for storing instructions, and the processor 110 is used for executing the instructions stored by the memory 120 to realize the steps correspondingly executed by the terminal in fig. 2-8.

Further, the communication device may also include an input port 140 and an output port 150. Wherein the processor 110, the memory 120, the input port 140, and the output port 150 may be connected by a bus 130.

The processor 110 is configured to execute the instructions stored in the memory 120 to control the input port 140 to receive signals and control the output port 150 to send signals, so as to complete the steps performed by the communication device in the above-mentioned method. Wherein input port 140 and output port 150 may be the same or different physical entities. When they are the same physical entity, they may be collectively referred to as an input-output port. The memory 120 may be integrated in the processor 110 or may be provided separately from the processor 110.

As an implementation manner, the functions of the input port 140 and the output port 150 may be implemented by a transceiver circuit or a dedicated chip for transceiving. The processor 110 may be considered to be implemented by a dedicated processing chip, processing circuit, processor, or a general-purpose chip.

As another implementation manner, a base station provided in this embodiment of the present application may be implemented by using a general-purpose computer. Program code that implements the functionality of processor 110, input ports 140 and output ports 150 is stored in memory, and a general purpose processor implements the functionality of processor 110, input ports 140 and output ports 150 by executing the code in memory.

For the concepts, explanations, details and other steps related to the technical solutions provided in the embodiments of the present application related to the communication apparatus, please refer to the description about the terminal in the foregoing method or other embodiments, which is not described herein again.

Please refer to fig. 11, which is a schematic diagram illustrating a network device according to an embodiment of the present disclosure; can include the following steps:

a receiving unit 300, configured to receive indication information sent by a terminal based on a first communication configuration, where the indication information corresponds to a second communication configuration, a sending unit 400, configured to send first acknowledgement information to the terminal, where the receiving unit 300 is further configured to receive an access notification message sent by the terminal based on the second communication configuration;

or, the receiving unit 300 is configured to receive an access notification message sent by the terminal based on the first communication configuration, and the sending unit 400 is configured to send second acknowledgement information to the terminal, where the second acknowledgement information is used to trigger the terminal to communicate with the network device based on the second communication configuration.

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

Optionally, the network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first communication configuration and the second communication configuration are in an MCG configuration; the access notification message is an RRC reconfiguration completion message;

Optionally, when the terminal is handed over to the target cell based on DAPS in combination with CHO, the indication information corresponding to the second communication configuration is used to notify the network device that the uplink transmission power of the terminal decreases;

Optionally, the network device is a master base station, the terminal is connected to the master base station and at least one secondary base station, a first secondary base station in the at least one secondary base station triggers the terminal to switch to the target cell, and the target cell is a cell managed by a target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

Optionally, in the process that the terminal determines to handover to the target cell until the terminal completes handover to the target cell, the sending unit is further configured to send, to the terminal, key indication information, where the key indication information is used to instruct the terminal to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

Optionally, the key indication information is included in a data packet sent by the network device to the terminal;

Optionally, the MAC CE or PDCP control information indicates a key used by the network device and a packet number encrypted using the key;

or, the MAC CE or PDCP control information indicates a key used by the network device and a preset time period for encrypting a data packet using the key.

For the concepts, explanations, details and other steps related to the technical solution provided in the embodiment of the present application related to the network device, please refer to the description about the first network device in the foregoing method or other embodiments, which is not described herein again.

Please refer to fig. 12, which is a schematic diagram illustrating another network device according to an embodiment of the present disclosure; may include a processor 210, a memory 220, and a bus 230. The processor 210 and the memory 220 are connected by a bus 230, the memory 220 is used for storing instructions, and the processor 210 is used for executing the instructions stored by the memory 220 to realize the steps correspondingly executed by the first network device in fig. 2-8.

Further, the network device may also include an input port 240 and an output port 250. Wherein the processor 210, memory 220, input 240, and output 250 may be coupled by a bus 230.

The processor 210 is configured to execute the instructions stored in the memory 220 to control the input port 240 to receive signals and control the output port 250 to send signals, so as to complete the steps performed by the first network device in the above-mentioned method. Wherein the input port 240 and the output port 250 may be the same or different physical entities. When they are the same physical entity, they may be collectively referred to as an input-output port. The memory 220 may be integrated in the processor 210 or may be provided separately from the processor 210.

As an implementation manner, the functions of the input port 240 and the output port 250 may be realized by a transceiver circuit or a dedicated chip for transceiving. Processor 210 may be considered to be implemented by a dedicated processing chip, processing circuit, processor, or a general purpose chip.

As another implementation manner, a terminal provided in this embodiment of the present application may be implemented by using a general-purpose computer. Program code that implements the functions of the processor 210, the input ports 240 and the output ports 250 is stored in memory, and a general purpose processor implements the functions of the processor 210, the input ports 240 and the output ports 250 by executing the code in the memory.

For the concepts, explanations, details and other steps related to the technical solutions provided in the embodiments of the present application related to the network device, please refer to the description of the first network device in the foregoing method or other embodiments, which is not described herein again.

Those skilled in the art will appreciate that only one memory and processor are shown in fig. 10 and 12 for ease of illustration. In an actual controller, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, and the like, which is not limited in this application.

It should be understood that, in the embodiment of the present Application, the processor may be a Central Processing Unit (CPU), and the processor may also be other general-purpose processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field-Programmable Gate arrays (FPGAs) or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components, and the like.

The memory may include both read-only memory and random access memory and provides instructions and data to the processor. The portion of memory may also include non-volatile random access memory.

The bus may include a power bus, a control bus, a status signal bus, and the like, in addition to the data bus. But for clarity of illustration the various buses are labeled as buses in the figures.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software. The steps of a method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in a processor. The software modules may be located in ram, flash, rom, prom, or eprom, registers, etc. as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor. To avoid repetition, it is not described in detail here.

According to the method provided by the embodiment of the present application, the embodiment of the present application further provides a system, which includes the terminal and the first network device.

In the embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various Illustrative Logical Blocks (ILBs) and steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. 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.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., coaxial cable, fiber optic, digital subscriber line) or wirelessly (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk), among others.

The contents of the various embodiments of the present application may be mutually referred to, and if there is no special description or logic conflict, terms and/or descriptions between different embodiments have consistency and may be mutually cited, technical features in different embodiments may be combined to form a new embodiment according to inherent logic relations thereof.

It is understood that, 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 other operations or variations of various operations may also be performed in the embodiments of the present application. 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.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for accessing a cell, wherein the method is used for a terminal to access a target cell, and the method comprises:

the method comprises the steps of sending indication information corresponding to second communication configuration to first network equipment based on the first communication configuration, receiving first confirmation information sent by the first network equipment, and sending an access notification message to the first network equipment based on the second communication configuration;

or sending an access notification message to the first network device based on the first communication configuration, receiving second acknowledgement information sent by the first network device, and communicating with the first network device based on a second communication configuration.

2. The method of claim 1, wherein the second communication configuration is updated from the first communication configuration.

3. The method of claim 1, wherein the first communication configuration and the second communication configuration comprise at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

4. The method according to claim 1, wherein the first network device is a primary base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first and second communication configurations are a master cell group, MCG, configuration; the access notification message is a Radio Resource Control (RRC) reconfiguration completion message;

5. The method according to claim 1, wherein when the terminal is handed over to the target cell based on dual activation protocol stack DAPS in combination with conditional handover CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the terminal decreases;

6. The method of claim 1, wherein the first network device is a master base station, the terminal connects the master base station and at least one secondary base station, and a first secondary base station of the at least one secondary base station triggers the terminal to handover to the target cell, and the target cell is a cell managed by the target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

7. The method according to claim 4 or 6, wherein in the process that the terminal determines that the handover to the target cell is completed to the terminal, the terminal sends key indication information to the first network device, and the key indication information is used for instructing the first network device to use a key in a first communication configuration or a key in a second communication configuration for data decryption.

8. The method according to claim 7, wherein the key indication information is included in a data packet sent by the terminal to the first network device;

9. The method of claim 8,

the MAC CE or PDCP control information indicates a key used by the terminal and a data packet number encrypted by using the key;

10. A method for accessing a cell, wherein the method is used for a terminal to access a target cell, and the method comprises:

11. The method of claim 10, wherein the second communication configuration is obtained by updating the first communication configuration.

12. The method of claim 10, wherein the first communication configuration and the second communication configuration comprise at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

13. The method according to claim 10, wherein the first network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first communication configuration and the second communication configuration are in an MCG configuration; the access notification message is an RRC reconfiguration completion message;

14. The method according to claim 10, wherein when the terminal is handed over to the target cell based on DAPS in combination with CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the terminal is decreased;

15. The method of claim 10, wherein the first network device is a master base station, the terminal connects the master base station and at least one secondary base station, and a first secondary base station of the at least one secondary base station triggers the terminal to handover to the target cell, and the target cell is a cell managed by the target secondary base station; the first communication configuration and the second communication configuration are Master Cell Group (MCG) configurations;

16. The method according to claim 13 or 15, wherein in a process that the terminal determines that the handover to the target cell is completed to the terminal, the first network device sends key indication information to the terminal, and the key indication information is used for instructing the terminal to perform data decryption by using a key in a first communication configuration or using a key in a second communication configuration.

17. The method according to claim 16, wherein the key indication information is included in a data packet sent by the first network device to the terminal;

18. The method of claim 17,

the MAC CE or PDCP control information indicates a key used by the first network device and a packet number encrypted using the key;

19. A communications apparatus, comprising:

or, the sending unit is configured to send an access notification message to the first network device based on the first communication configuration, the receiving unit is configured to receive second acknowledgement information sent by the first network device, and the sending unit and the receiving unit are further configured to communicate with the first network device based on a second communication configuration.

20. The communications apparatus of claim 19, wherein the second communication configuration is updated from the first communication configuration.

21. The communications apparatus of claim 19, wherein the first communication configuration and the second communication configuration comprise at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

22. The communications apparatus as claimed in claim 19, wherein the first network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the communications apparatus or a newly added target primary and secondary cell to be accessed; the first and second communication configurations are a master cell group, MCG, configuration; the access notification message is a Radio Resource Control (RRC) reconfiguration completion message;

23. The communications apparatus according to claim 19, wherein when the communications apparatus is handed over to the target cell based on dual activation protocol stack DAPS in conjunction with conditional handover CHO, the indication information corresponding to the second communication configuration is used to notify the first network device that the uplink transmission power of the communications apparatus is decreased;

24. The communications apparatus of claim 19, wherein the first network device is a master base station, the communications apparatus connects the master base station and at least one secondary base station, a first secondary base station of the at least one secondary base station triggers the communications apparatus to handover to the target cell, and the target cell is a cell managed by a target secondary base station; the first communication configuration and the second communication configuration are Master Cell Group (MCG) configurations;

25. The communications apparatus according to claim 22 or 24, wherein in a process in which the communications apparatus determines that the handover to the target cell to the communications apparatus is completed to the target cell, the communications apparatus sends key indication information to the first network device, the key indication information being used to instruct the first network device to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

26. The communications apparatus according to claim 25, wherein the key indication information is included in a data packet transmitted by the communications apparatus to the first network device;

27. The communication device of claim 26,

the MAC CE or PDCP control information indicating a key used by the communication apparatus and a packet number encrypted using the key;

28. The communications device of claim 19, wherein the communications device is a terminal.

29. A network device, comprising:

the terminal comprises a receiving unit, a sending unit and an access notification unit, wherein the receiving unit is used for receiving indication information sent by the terminal based on first communication configuration, the indication information corresponds to second communication configuration, the sending unit is used for sending first confirmation information to the terminal, and the receiving unit is also used for receiving the access notification message sent by the terminal based on the second communication configuration;

30. The network device of claim 29, wherein the second communication configuration is updated from the first communication configuration.

31. The network device of claim 29, wherein the first communication configuration and the second communication configuration comprise at least one of:

a key for encrypting and decrypting data;

frequency band of the transmitted information;

maximum transmission power when transmitting information.

32. The network device according to claim 29, wherein the network device is a master base station, and the target cell is a target primary and secondary cell to be switched by the terminal or a newly added target primary and secondary cell to be accessed; the first communication configuration and the second communication configuration are in an MCG configuration; the access notification message is an RRC reconfiguration completion message;

33. The network device of claim 29, wherein when the terminal is handed over to the target cell based on DAPS in combination with CHO, the indication information corresponding to the second communication configuration is used to notify the network device that the uplink transmission power of the terminal decreases;

34. The network device of claim 29, wherein the network device is a master base station, the terminal connects the master base station and at least one secondary base station, a first secondary base station of the at least one secondary base station triggers the terminal to handover to the target cell, and the target cell is a cell managed by a target secondary base station; the first and second communication configurations are a master cell group, MCG, configuration;

35. The network device according to claim 32 or 34, wherein in a process that the terminal determines that the handover to the target cell is completed to the terminal, the sending unit is further configured to send, to the terminal, key indication information for instructing the terminal to perform data decryption using a key in a first communication configuration or using a key in a second communication configuration.

36. The network device of claim 35, wherein the key indication information is included in a data packet sent by the network device to the terminal;

37. The network device of claim 16,

the MAC CE or PDCP control information indicates a key used by the network equipment and a data packet number encrypted by using the key;

38. A communications apparatus, comprising:

a processor, a memory and a bus, the processor and the memory being connected by the bus, wherein the memory is configured to store a set of program codes, and the processor is configured to call the program codes stored in the memory to perform the method according to any one of claims 1-9.

39. A network device, comprising:

a processor, a memory and a bus, the processor and the memory being connected by the bus, wherein the memory is configured to store a set of program codes, and the processor is configured to call the program codes stored in the memory to perform the method according to any one of claims 10-18.

40. A computer-readable storage medium, comprising:

the computer readable storage medium has stored therein instructions which, when run on a computer, implement the method of any one of claims 1-9 or 10-18.

41. A chip comprising one or more processing circuits, wherein the one or more processing circuits are to implement the method of any one of claims 1-9 or 10-18.