WO2022104751A1

WO2022104751A1 - Method and apparatus for wireless communication apparatus, storage medium, and chip system

Info

Publication number: WO2022104751A1
Application number: PCT/CN2020/130659
Authority: WO
Inventors: 文露涛; 罗小烽
Original assignee: 华为技术有限公司
Priority date: 2020-11-20
Filing date: 2020-11-20
Publication date: 2022-05-27
Also published as: CN114830731A

Abstract

Disclosed in the present application are a method and apparatus for a wireless communication apparatus, a storage medium, and a chip system, for use in enabling a wireless communication apparatus to fall back from a 5G system to a 2G or 3G communication system to complete a service, and then return to the 5G system. The method comprises: a wireless communication apparatus initiating a voice service in a first cell of a 5G communication system; performing the voice service on a second cell of a 2G or 3G communication system; sending a first message on the second cell, the first message being used for indicating the end of the voice service; receiving a second message on the second cell, the second message being used for instructing the wireless communication apparatus to redirect to a third cell of a 4G communication system; and after receiving the second message, searching for a cell of the 5G communication system before attempting to access the third cell, and when a suitable 5G cell is found, attempting to access the 5G cell. In this way, a terminal device can return to a first communication system more quickly.

Description

Method, device, storage medium and chip system for wireless communication device

technical field

The present application relates to the field of mobile communication technologies, and in particular, to a method, a device, a storage medium and a chip system for a wireless communication device.

Background technique

Circuit Switched Fallback (CSFB) is a temporary solution for making calls on LTE before Long Term Evolution (LTE) supports IP Multimedia Subsystem (IMS). The specific implementation process is as follows:

When a terminal device residing on LTE has a voice calling or being called, after sending an Extended Service Request message to the LTE network, the LTE network sends a redirection message to redirect the terminal device residing on LTE. To the second generation (The Second Generation, 2G) communication system or the third generation (The Third Generation, 3G) communication system, in order to conduct a voice session (ie, CS voice session) in the circuit switched (Circuit Switch, CS) domain. Among them, the voice session initiated in the coverage area of the LTE network and then conducted through the CSFB may be referred to as a CSFB CS voice session. When the CSFB CS voice session ends, the 2G or 3G communication network uses the Fast Return scheme specified in the 3GPP standard to issue a Channel Release message. The Channel Release message carries the frequency points in the LTE communication system. Guide the terminal equipment to return to the LTE communication network at the fastest speed.

With the development of 5G communication technology, more and more terminal devices are connected to the 5G communication system. However, the current 5G communication systems in some regions may not support interoperability with the traditional circuited switched (CS) domain. In this case, when the terminal device residing in the 5G system has a voice session service, the terminal device may need to fall back to LTE through redirection for voice service. However, if the fallen LTE communication system cannot provide the voice session service, the terminal device needs to fall back to the 2G or 3G communication system to perform the voice session service. When the terminal equipment falls back from the NR communication system to the 2G or 3G communication system and completes the voice session service, how to return to the NR communication system? There is an urgent need to resolve this issue.

SUMMARY OF THE INVENTION

The present application provides a method, a device, a storage medium and a chip system for a wireless communication device, which are used to optimize the communication performance when the wireless communication device supports multiple communication systems.

In a first aspect, an embodiment of the present application provides a method for a wireless communication device, in which the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the second communication system. After receiving the second message, before attempting to access the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is found, the cell of the first communication system is attempted to be accessed.

In this way, when the wireless communication device falls back from the first communication system to the third communication system to perform the voice service and ends the voice service on the third communication system, although the network device instructs the terminal device to redirect to the second communication system through the second message However, after receiving the second message, the wireless communication system does not directly attempt to access the cell of the second communication system, but first attempts to access the cell of the first communication system. Compared with the solution in which the wireless communication apparatus first accesses the cell of the second communication system and then accesses the cell of the first communication system after receiving the second message, this solution can make the terminal device return to the first communication system more quickly.

It should be understood that, in the solutions provided by the embodiments of the present application, the wireless communication device may be a wireless communication device, or may be a part of a device in the wireless communication device, such as an integrated circuit product such as a system chip or a communication chip. The wireless communication device may be a computer device that supports wireless communication functionality.

Specifically, the wireless communication device may be a terminal such as a smart phone, or may be a wireless access network device such as a base station. A system-on-chip may also be referred to as a system on chip (system on chip, SoC), or simply referred to as a SoC chip. The communication chip may include a baseband processing chip and a radio frequency processing chip. Baseband processing chips are also sometimes referred to as modems or baseband chips. The radio frequency processing chip is also sometimes referred to as a radio frequency transceiver (transceiver) or radio frequency chip. In physical implementation, some or all of the communication chips may be integrated inside the SoC chip. For example, the baseband processing chip is integrated in the SoC chip, and the radio frequency processing chip is not integrated with the SoC chip.

In a possible implementation manner, the standard priority of the first communication system is higher than that of the second communication system, and the standard priority of the second communication system is higher than that of the third communication system. The priority of the standard of the communication system may be preset.

In a possible implementation manner, the first communication system is a 5G communication system, the second communication system is a 4G communication system, and the third communication system is a 2G communication system or a 3G communication system. Based on this embodiment, the method provided by the first aspect may also include the following content: initiating a voice service in a first cell, where the first cell is a cell of a 5G communication system; and performing a voice service in a second cell, where the second cell is 2G A cell of a communication system or a 3G communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the 4G communication system. After receiving the second message, before attempting to access the third cell, search for a cell in the 5G communication system, and try to access the 5G cell when a suitable 5G cell is found.

In a possible implementation manner, the wireless communication device may be the calling party or the called party. When the wireless communication device is the calling party, the wireless communication device may send the data on the first cell based on a trigger of a user operation. The session invitation message is used to initiate a voice service. When the wireless communication device is the called party, the wireless communication device may receive a paging message on the first cell, where the paging message is used to indicate to the wireless communication device that another wireless communication device initiates a voice service to the wireless communication device.

When the wireless communication device cannot perform the voice service on the first communication system, it can fall back to the third communication system by means of an instruction of the network device, or can fall back to the third communication system autonomously. For example, the wireless communication device may receive an air interface message from the network device after initiating the voice service in the first cell and before continuing the voice service in the second cell, where the air interface message is used to instruct the wireless communication device to access the second cell. For another example, after the wireless communication device initiates the voice service in the first cell, and before the voice service is performed in the second cell, the method further includes: accessing the second cell based on a method of actively changing cells.

In a possible implementation manner, when the wireless communication apparatus searches for a cell of the first communication system, it may search for the first cell. In a possible implementation, when the first cell is unavailable, a historical cell of the first communication system is searched. In this way, it is possible to return to the cell or historical cell where the wireless communication device resided before initiating the voice service more quickly.

In a possible implementation manner, when the wireless communication device attempts to access the cell of the first communication system, a connection establishment request may be sent on the cell of the first communication system, and the connection establishment request is used to request to establish a connection with the first communication system. Wireless connection of cells of a communication system. In this way, after the wireless communication device successfully accesses the cell of the first communication system, a service can be performed in the cell of the first communication system, such as a data service or a voice service.

In a possible implementation manner, after the access to the cell of the first communication system fails, an attempt is made to access the third cell. In this way, a wireless communication device that cannot access the first communication system can be made to access the second communication system, so as to perform services, such as data services or voice services.

In a possible implementation manner, the first message is a call hang-up message, and the second message is a connection release message. In this way, it can be more compatible with the existing technology.

In a second aspect, an embodiment of the present application provides a method for a wireless communication device, in which the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the second communication system. After receiving the second message, try to access the third cell. When a radio connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

Different from the method provided in the first aspect, after receiving the second message, the wireless communication apparatus performs an action based on the response to the second message: searching for a cell of the first communication system. In the method provided in the second aspect, after receiving the second message, the wireless communication device performs an action based on the response to the second message: attempt to access the third cell. And when the wireless connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

In this way, when the terminal device falls back to the second communication system, it can search the frequency point of the first communication system after receiving the wireless connection release message. In a possible implementation, the terminal device falls back to the second communication system. Then, the frequency point of the first communication system is searched after entering the idle state. Compared with the solution in which the terminal device performs cell replacement only when the signal quality of the currently camped cell is found to be poor, the speed at which the terminal device returns to the first communication system can be accelerated.

In a possible implementation manner, the first communication system is a 5G communication system, the second communication system is a 4G communication system, and the third communication system is a 2G communication system or a 3G communication system. Based on this embodiment, the method provided in the second aspect may also include the following content: initiating a voice service in a first cell, where the first cell is a cell of a 5G communication system; and performing a voice service in a second cell, where the second cell is 2G A cell of a communication system or a 3G communication system; a first message is sent on the second cell, and the first message is used to indicate the end of the voice service; a second message is received on the second cell, and the second message is used to instruct the wireless communication device to restart. Directed to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the 4G communication system; after receiving the second message, try to access the third cell; receive on the third cell When the wireless connection release message arrives, the cell of the 5G communication system is searched, and when a suitable 5G cell is found, it attempts to access the 5G cell.

In a possible implementation manner, the wireless communication device may be the calling party or the called party. When the wireless communication device is the calling party, the wireless communication device may send the data on the first cell based on a trigger of a user operation. The session invitation message is used to initiate a voice service. When the wireless communication device is the called party, the wireless communication device may

A paging message is received on the first cell, and the paging message is used to instruct the wireless communication device to initiate a voice service. It can also be understood that the paging message is used to indicate that the wireless communication device has other wireless communication devices that initiate a voice service to it.

In a third aspect, an embodiment of the present application provides a method for a wireless communication device, in which the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A third message is received on the second cell, where the third message is used to instruct the wireless communication device to redirect to the fourth cell, the third message includes information of the fourth cell, and the fourth cell is a cell of the first communication system. After receiving the third message, try to access the fourth cell. In this way, the wireless communication device can be redirected to the cell of the first communication system based on the third message, thereby improving the speed at which the wireless communication device returns to the first communication system.

In a possible implementation manner, when the third message includes the information of the fourth cell, the third message may further include the information of the third cell. In this way, when the terminal device fails to access the cell of the first communication system, it can try to access the third cell according to the third message.

In a possible implementation manner, the wireless communication device may be the calling party or the called party. When the wireless communication device is the calling party, the wireless communication device may send the data on the first cell based on a trigger of a user operation. The session invitation message is used to initiate a voice service. When the wireless communication device is the called party, the wireless communication device may receive a paging message on the first cell, where the paging message is used to instruct the wireless communication device to initiate a voice service. It can also be understood that the paging message is used to indicate that the wireless communication device has other wireless communication devices that initiate a voice service to it.

In a possible implementation manner, when the wireless communication apparatus attempts to access the fourth cell, it may search for a frequency point of the first cell; when the first cell is available, it may access the first cell. The information of the fourth cell is the frequency of the first cell. Further, in a possible implementation manner, the wireless communication apparatus may send a connection establishment request on the first cell, where the connection establishment request is used to request to establish a wireless connection with the first cell. In a possible implementation manner, after the access to the first cell of the first communication system is successful, a service is performed in the first cell of the first communication system, such as a data service or a voice service.

In yet another possible implementation, when the first cell is unavailable, a historical cell of the first communication system is searched. In a possible implementation manner, after searching for a suitable cell of the first communication system, a connection establishment request is sent on the cell of the first communication system, where the connection establishment request is used to request to establish a connection with the cell of the first communication system wireless connection. In a possible implementation manner, after the access to the cell of the first communication system is successful, a service is performed in the cell of the first communication system, such as a data service or a voice service.

In a possible implementation manner, the first message is a call hang-up message, and the third message is a connection release message. In this way, it can be more compatible with the existing technology.

Corresponding to any communication method from the first aspect to the third aspect, the present application further provides a communication device. The communication apparatus may be any device on the sending end or device on the receiving end that performs data transmission in a wireless manner. For example, a communication chip, a wireless communication device, or a network device (such as a base station, etc.). During the communication process, the device on the sending end and the device on the receiving end are relative. In some communication processes, the communication device can be used as the above-mentioned network device or a communication chip that can be used in the network device; in some communication processes, the communication device can be used as the above-mentioned wireless communication device or a communication chip that can be used in the wireless communication device.

In a fourth aspect, a wireless communication apparatus is provided, including a communication unit and a processing unit, so as to execute any one of the implementation manners of any one of the communication methods of the first aspect to the third aspect. The communication unit is used to perform functions related to transmission and reception. Optionally, the communication unit includes a receiving unit and a sending unit. In one design, the wireless communication device is a communication chip, the processing unit may be one or more processors or processor cores, and the communication unit may be an input/output circuit or port of the communication chip.

In another design, the communication unit may be a transmitter and receiver, or the communication unit may be a transmitter and receiver.

Optionally, the wireless communication apparatus further includes various modules that can be used to execute any one of the implementation manners of any one of the communication methods of the first aspect to the third aspect.

In a fifth aspect, a wireless communication device is provided, including a processor and a memory. Optionally, it also includes a transceiver, the memory is used to store a computer program or instruction, the processor is used to call and run the computer program or instruction from the memory, and when the processor executes the computer program or instruction in the memory, make the computer program or instruction in the memory. The wireless communication apparatus executes any one of the implementations of any one of the communication methods of the first aspect to the third aspect.

Optionally, there are one or more processors and one or more memories.

Optionally, the memory may be integrated with the processor, or the memory may be provided separately from the processor.

Optionally, the transceiver may include a transmitter (transmitter) and a receiver (receiver).

In a sixth aspect, a wireless communication apparatus is provided, including a processor. The processor, coupled to the memory, is operable to perform the method of any one of the first to third aspects, and any one of the possible implementations of the first to third aspects. Optionally, the wireless communication device further includes a memory. Optionally, the wireless communication device further includes a communication interface, and the processor is coupled to the communication interface.

In an implementation manner, when the wireless communication apparatus is a wireless communication device, the communication interface may be a transceiver, or an input/output interface. Optionally, the transceiver may be a transceiver circuit. Alternatively, the input/output interface may be an input/output circuit.

In yet another implementation, when the wireless communication device is a chip or a chip system, the communication interface may be an input/output interface, an interface circuit, an output circuit, an input circuit, a pin or a related circuit on the chip or a chip system Wait. A processor may also be embodied as a processing circuit or a logic circuit.

In a seventh aspect, a system is provided, which includes the above-mentioned wireless communication apparatus and network equipment.

In an eighth aspect, a computer program product is provided. The computer program product includes: a computer program (also referred to as code, or instruction), which, when the computer program is executed, enables the computer to execute any one of the above-mentioned first aspects. The method in the manner, or causing the computer to execute the method in any one of the implementation manners of the first aspect to the third aspect.

In a ninth aspect, a computer-readable storage medium is provided, and the computer-readable medium stores a computer program (also referred to as code, or instruction), when it runs on a computer, so that the computer executes any one of the above-mentioned first aspects. The method in one possible implementation manner, or causing the computer to execute the method in any one of the implementation manners of the first aspect to the third aspect.

In a tenth aspect, a system-on-chip is provided, and the system-on-chip may include a processor. The processor, coupled to the memory, is operable to perform the method of any one of the first to third aspects, and any one of the possible implementations of any of the first to third aspects. Optionally, the chip system further includes a memory. Memory, used to store computer programs (also called code, or instructions). A processor for invoking and running a computer program from a memory, so that a device on which the chip system is installed performs any one of the first to third aspects, and any one of the first to third aspects is possible method in the implementation.

In an eleventh aspect, a wireless communication device is provided, comprising: an interface circuit and a processing circuit. The interface circuits may include input circuits and output circuits. The processing circuit is configured to receive the signal through the input circuit and transmit the signal through the output circuit, so that the method of any one of the first to third aspects and any one of possible implementations of the first to third aspects is implemented.

In a specific implementation process, the above-mentioned processing device may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a flip-flop, and various logic circuits. The input signal received by the input circuit may be received and input by, for example, but not limited to, a receiver, the signal output by the output circuit may be, for example, but not limited to, output to and transmitted by a transmitter, and the input circuit and output The circuit can be the same circuit that acts as an input circuit and an output circuit at different times. The embodiments of the present application do not limit the specific implementation manners of the processor and various circuits.

In an implementation manner, when the wireless communication apparatus is a wireless communication device, the wireless communication device may be a terminal such as a smart phone, or may be a wireless access network device such as a base station. The interface circuit may be a radio frequency processing chip in the wireless communication device, and the processing circuit may be a baseband processing chip in the wireless communication device.

In yet another implementation manner, the wireless communication apparatus may be a part of a wireless communication device, such as an integrated circuit product such as a system chip or a communication chip. The interface circuit may be an input/output interface, an interface circuit, an output circuit, an input circuit, a pin or a related circuit, etc. on the chip or the chip system. The processing circuit may be a logic circuit on the chip.

Description of drawings

FIG. 1 is a schematic diagram of the architecture of a communication system provided by an embodiment of the present application;

FIG. 2a is a schematic flowchart of a method for a wireless communication device according to an embodiment of the present application;

FIG. 2b is a schematic flowchart of another method for a wireless communication device provided by an embodiment of the present application;

3a is a flowchart of a method for initiating a voice service when the wireless communication device provided by the embodiment of the present application is a calling party;

3b is a flowchart of a method for initiating a voice service when the wireless communication device provided by the embodiment of the application is the called party;

3c is a schematic flowchart of a method for a wireless communication device to fall back from a first communication system to a third communication system according to an embodiment of the present application;

FIG. 3d is a schematic flowchart of the above-mentioned method from steps S205 to S207 according to an embodiment of the present application;

FIG. 4a is a schematic flowchart of a method for a wireless communication device according to an embodiment of the present application;

FIG. 4b is a schematic flowchart of a method of step S405 provided by an embodiment of the present application;

5a is a schematic flowchart of a method for a wireless communication device provided by an embodiment of the present application;

FIG. 5b is a schematic flowchart of a method of step S505 provided by an embodiment of the present application;

FIG. 6a is a schematic structural diagram of a communication device according to an embodiment of the present application;

FIG. 6b is a schematic structural diagram of a communication device provided by an embodiment of the present application;

FIG. 7 is a schematic structural diagram of another communication apparatus provided by an embodiment of the present application;

FIG. 8 is a schematic structural diagram of another communication device provided by an embodiment of the present application;

FIG. 9 is a schematic structural diagram of another communication apparatus provided by an embodiment of the present application.

Detailed ways

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

The embodiments of the present application may be applied to a wireless communication system. The wireless communication system may comply with the wireless communication standard of the third generation partnership project (3GPP), or may comply with other wireless communication standards, such as the 802 of the Institute of Electrical and Electronics Engineers (IEEE). series (such as 802.11, 802.15, or 802.20) of wireless communication standards.

The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), General Packet Radio Service (General Packet Radio Service) packet radio service, GPRS), GSM Enhanced Data rates for GSM Evolution (EDGE), Transitional Standard 95 Code Division Multiple Access (Interim Standard 95CDMA, IS-95CDMA), Wideband Code Division Multiple Access (Wideband Code Division Multiple Access) Access, WCDMA), CDMA2000, Time Division Synchronous Code Division Multiple Access (TD-SCDMA), LTE, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access, WiMAX) communication systems, as well as 5G communication systems and future communication systems, etc. Among them, LTE includes time division duplex LTE (LTETDD, or TD-LTE) and frequency division duplex LTE (LTE FDD).

Among them, the two systems of TD-SCDMA and WCDMA are the Universal Mobile Telecommunication System (UMTS) of 3G mobile phone technology. UMTS is promulgated by the standardization organization 3GPP (The 3rd Generation Partnership Project, the third generation partnership project). . The network structure of UMTS can be divided into UMTS Terrestrial Radio Access Network (UMTS Terrestrial Radio Access Network, UTRAN) and core network (Core Network, CN). In the UTRAN architecture, the radio access network (Radio Access Network, RAN) is divided into multiple radio network subsystems (Radio Network Subsystem, RNS), each RNS includes a radio network controller (Radio Network Controller, RNC) and One or more Node Bs (base stations). The RNC is responsible for allocating, reconfiguring and releasing the radio resources in the RNS. The Node B is a node with wireless transceiver function, which supports the air interface with the wireless terminal equipment within the cell range and provides services for the cell. The Node B and RNC communicate through the Iub interface, and the RNCs can be interconnected through an interface including a direct physical connection or a virtual network using any suitable transport network.

Unless otherwise specified, the 2G communication system usually includes GSM, CDMA, GPRS, EDGE and IS-95CDMA. 3G communication systems usually include TD-SCDMA, WCDMA, and upgrades of CDMA2000 and CDMA2000. The 4G communication system includes LTE. The 5G communication system includes NR. At present, the terminal equipment can also support multiple communication systems, and then can realize roaming in multiple communication systems.

The embodiments of the present application relate to a first communication system, a second communication system, and a third communication system. Wherein, the standard priority of the first communication system is higher than that of the second communication system, and the standard priority of the second communication system is higher than that of the third communication system. In the embodiments of this application, the first communication system is a 5G communication system, the second communication system is a 4G communication system, and the third communication system is a 2G communication system or a 3G communication system. The priority of the standard of a communication system in this embodiment of the present application may be preset. For example, the priority of the standard of the 5G communication system is higher than that of the standard of the 4G communication system, and the priority of the standard of the 4G communication system is higher than that of the standard of the 4G communication system. The priority of the standard of the 3G communication system, the priority of the standard of the 3G communication system is higher than the priority of the standard of the 2G communication system.

Those skilled in the art know that the first communication system, the second communication system, and the third communication system may also be other communication systems. For example, the first communication system may also be a future communication system with a higher standard than 5G, such as the future 6G , 7G, etc., the second communication system may be a 5G communication system, and the third communication system may be a 4G communication system.

A communication system usually includes access network equipment and core network equipment. Among them, the access network (radio access network, RAN) equipment: mainly responsible for the radio resource management, quality of service (quality of service, QoS) management, data compression and encryption functions on the air interface side. The access network equipment may include various forms of base stations, such as: a macro base station, a micro base station (also referred to as a small cell), a relay station, an access point, and the like.

Core network equipment is used to provide user connections, manage users, and carry services. For example, the establishment of user connection includes functions such as mobility management (mobile management, MM) and paging (paging). User management includes user description, QoS, and security (corresponding security measures provided by the authentication center include security management of mobile services and security processing of external network access). Bearer connections include external public switched telephone networks (PSTN), external circuit data networks and packet data networks, the Internet, and the like.

FIG. 1 exemplarily shows a schematic diagram of the architecture of a communication system provided by an embodiment of the present application. As shown in FIG. 1 , the communication system may include one or more terminal devices, such as the terminal device 100 shown in FIG. 1 and the Terminal device 104 . The wireless communication apparatus mentioned in the embodiments of this application may be a terminal device, or a chip provided in the terminal device.

The terminal device in this embodiment of the present application includes a device that provides voice and/or data connectivity to a user, and may include, for example, a handheld device with a wireless connection function, or a processing device connected to a wireless modem. The terminal equipment may communicate with the core network via a radio access network (RAN), and exchange voice and/or data with the RAN. The terminal equipment may include user equipment (UE), wireless terminal equipment, mobile terminal equipment, device-to-device (D2D) terminal equipment, V2X terminal equipment, machine-to-machine/machine-type communication ( machine-to-machine/machine-type communications, M2M/MTC) terminal equipment, Internet of things (IoT) terminal equipment, subscriber unit (subscriber unit), subscriber station (subscriber station), mobile station (mobile station) , remote station (remote station), access point (access point, AP), remote terminal equipment (remote terminal), access terminal equipment (access terminal), user terminal equipment (user terminal), user agent (user agent), or user device, etc. For example, these may include mobile telephones (or "cellular" telephones), computers with mobile terminal equipment, portable, pocket-sized, hand-held, computer-embedded mobile devices, and the like. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (personal digital assistants), PDA), etc. Also includes constrained devices, such as devices with lower power consumption, or devices with limited storage capacity, or devices with limited computing power, etc. For example, it includes information sensing devices such as barcodes, radio frequency identification (RFID), sensors, global positioning system (GPS), and laser scanners.

User information is stored in the terminal device. The subscriber information may include an IMSI, which may be stored in a subscriber identity module (SIM) card of the terminal device. The terminal device can use the user information as an identity to initiate a call to other terminal devices through various voice solutions, and perform audio and video communication after the other terminal device accepts the call. For example, in FIG. 1 , the terminal device 100 may initiate a call to the terminal device 104 , and the terminal device 104 may also initiate a call to the terminal device 100 .

As shown in FIG. 1, the communication system architecture may include a 5G communication system 103. The 5G communication system 103 includes: 5G access network equipment 101 and 5G core network (5G core network, 5GC) equipment 102. The 5G access network equipment 101 is connected to to the 5GC facility 102 .

The 5G access network device 101 may be a next generation NodeB (gNB). As shown in FIG. 1 , the gNB can be connected to the terminal device 100 and communicate with the terminal device 100 using a new radio (NR) access technology, that is, the gNB and the terminal device 100 communicate through an NR link .

The network elements in the 5GC equipment are functional virtual units, which may include but are not limited to: units for access and mobility management functions (access and mobility management functions, AMF), units for session management functions (session management functions) , SMF), network elements for unified data management (unified data management, UDM), etc.

In the 5G communication system, a multimedia subsystem (Internet Protocol Multimedia subsystem, IMS) based on a network protocol can be provided. The IMS is used to manage the IP data packets packaged into multimedia data such as voice and video, distinguish the signaling part and the multimedia data part of these IP data packets, and transmit the IP data packets between the terminal device 100 and the called end of the call. Multimedia data part, so as to provide audio and video services for the terminal device 100. The IMS may mainly include a call session control function (call session control function, CSCF) and a home subscriber server (home subscriber server, HSS). CSCF is used to control signaling, authentication, and cooperation with other network entities to control the session during multimedia call sessions. HSS is used to manage user data.

After the 5G communication system deploys IMS, the 5G communication system can support VoNR voice services. VoNR means that the call data is carried by the 5G communication system 103 during the call. The terminal device 100 calling the terminal device 104 through VoNR means that the terminal device 100 requests to communicate the control plane signaling (IMS signaling) and user plane data involved in the call process between the terminal device 100 and the terminal device 104 through the 5G communication system 103 and the IMS 300. (IMS traffic) are packaged as IP packets and transmitted. In this case, both the service data and the voice data involved in the terminal device 100 are transmitted in the form of IP data packets.

As shown in FIG. 1 , the communication system architecture may further include a 4G communication system 113. The 4G communication system 113 includes: a 4G access network device 111 and a 4G core network (evolved packet core, EPC) 112. The 4G access network device 111 Connect to EPC device 112 .

The 4G access network device 111 may be an evolved base station (evolved Node B, eNB). As shown in FIG. 1 , the terminal device 100 may be located within the signal coverage of the 4G access network device 111 . The terminal device 100 may be connected to the 4G access network device 111 and communicate with the 4G access network device 111 through an LTE link.

The EPC device 112 mainly includes the following network elements: a mobility management entity (MME), a serving gateway (SGW), a packet data network gateway (PGW), a home subscriber server (home subscriber server, HSS) and application server, etc. The main functions of the MME include access control, mobility management, attach and detach, session management (eg, bearer establishment, modification, and release), and so on. The SGW is mainly used for routing and forwarding of data packets. The main functions of the PGW include user-based packet filtering, lawful interception, and IP address allocation. The HSS is used to store user subscription information, user subscription data, and location information of mobile users.

After the 4G communication system deploys the IMS, the 4G communication system can support the VoLTE voice service. VoLTE means that call data is carried by the 4G communication system 113 during a call. The terminal equipment calls the terminal equipment 104 through VoLTE means that the terminal equipment 100 requests to communicate the control plane signaling (IMS signaling) and the user plane data ( IMS traffic) are packaged as IP packets and transmitted. In this case, both the service data and the voice data involved in the terminal device 100 are transmitted in the form of IP data packets.

As shown in FIG. 1 , the communication system architecture may further include a 2G/3G communication system 123 . The 2G/3G communication system 123 may include: a 2G/3G access network device 121 and a 2G/3G core network device 122 . 2G/3G in the embodiments of this application refers to 2G and/or 3G, wherein the 2G communication system includes 2G core network equipment and 2G access network equipment, and the 3G communication system includes 3G core network equipment and 3G access network equipment.

The 2G access network equipment can be a base transceiver station (base transceiver station, BTS) and a base station controller (base station controller, BSC). A 3G access network device may be a Node B (NodeB) or a base station or a radio network controller (RNC). The 2G/3G core network device 122 may be a mobile switching center (Mobile Switching Center, MSC), a base station controller (base station controller, BSC), and the like.

The terminal device 100 can be connected to the 2G/3G access network device 121, and communicate with the 2G/3G access network device 121 through a global system for mobile communications (GSM), a universal mobile telecommunications system) and other links to communicate with each other.

The 2G/3G core network device 122 includes a CS domain, and the 2G/3G communication system 123 can provide audio and video services on the CS session, that is, the 2G/3G communication system 123 supports a voice solution based on the CS domain. The voice solution based on the CS domain refers to establishing an exclusive channel between two or more terminal devices through the traditional CS domain, and using this channel for audio and video communication. The CS (Circuit Switch) service involved in the embodiments of the present application means a circuit switching service. CSs are resources allocated exclusively by different users. CS services mainly include some voice services, such as 12.2K voice services, 64K video telephony services, and so on. For example, taking the voice service as an example, the exclusive channel is not released until the end of the call for other users to use.

In a wireless communication system, a network device (such as a base station) can provide communication coverage for a specific geographic area through an integrated or external antenna device. One or more wireless communication devices located within the communication coverage of the network device can access the network device. A network device can manage one or more cells. Each cell has an identification, which is also called a cell identity (cell ID). From the perspective of radio resources, a cell is a combination of downlink radio resources and paired uplink radio resources (optional).

The wireless communication device and network equipment should know the predefined configuration of the wireless communication system, including the radio access technology (RAT) supported by the system and the wireless resource configuration specified by the system, such as the basic configuration of the radio frequency band and carrier . A carrier is a frequency range that conforms to system regulations. This frequency range can be determined by the center frequency of the carrier (referred to as the carrier frequency) and the bandwidth of the carrier. These system predefined configurations may be part of the standard protocols of the wireless communication system, or determined through interaction between wireless communication devices and network equipment. The content of the relevant standard protocol may be pre-stored in the memory of the wireless communication device and the network device, or embodied as a hardware circuit or software code of the wireless communication device and the network device.

In the wireless communication system, the wireless communication device and the network device support one or more of the same RATs, such as 5G NR, 4G LTE, or RATs of future evolution systems. Specifically, the wireless communication device and the network device use the same air interface parameters, coding scheme, modulation scheme, etc., and communicate with each other based on the wireless resources specified by the system.

In an embodiment of the present application, after the call initiated by the terminal device 100 to the terminal device 104 using 5G VoNR fails (for example, the current 5G cell does not support VoNR), the terminal device can use VoLTE to initiate a call to the terminal device 104 again, If the call fails (for example, the current 4G cell does not support VoLTE), the service (eg, voice service) needs to be implemented again through the circuit domain of the 2G or 3G communication system. After the service ends, how to return to the 5G cell is a problem to be solved in the embodiment of the present application.

In the following embodiments of the present application, a call refers to a process in which one terminal device initiates a voice call request to another terminal device. One terminal device that initiates a call is the calling end, and another terminal device that receives the call is the called end. After the called end accepts the call, the calling end and the called end can talk, that is, data such as voice can be transmitted between the calling end and the called end, so as to provide multimedia services such as voice and video for users at both ends. In the process of calling and talking, the calling end and the called end can use the International Mobile Subscriber Identification Number (IMSI) as the identity.

In the embodiment of the present application, the voice scheme involved when the terminal device initiates a call may include, but is not limited to: VoNR, IMS-based voice on long term evolution (voice on long term evolution, VoLTE), CS domain-based voice scheme, and so on. Subsequent embodiments will describe the specific implementation process of the above voice solution in detail, which will not be repeated here.

It can be understood that, in the communication system shown in FIG. 1 , the functions and interfaces of each network element are only exemplary, and not all functions of each network element are required when applied to the embodiments of the present application.

In the embodiments of this application, a certain network element (for example: A network element) receives information from another network element (for example: B network element), which may mean that A network element directly receives information from B network element, or It means that the A network element receives information from the B network element via other network elements (for example, the C network element). When network element A receives information from network element B via network element C, network element C can transparently transmit the information, or process the information, such as carrying the information in different messages for transmission or filtering the information. , only the filtered information is sent to NE A. Similarly, in the embodiments of this application, the sending of information by network element A to network element B may refer to network element A sending information directly to network element B, or it may refer to network element A sending information to network element B via other network elements (for example, network element C element) to send information to network element B.

In the embodiments of the present application, the term "system" may be interchanged with "network". The system architecture described in the embodiments of the present application is to more clearly describe the technical solutions of the embodiments of the present application, and does not constitute a limitation on the technical solutions provided by the embodiments of the present application. , the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

Based on the above content, Fig. 2a exemplarily shows a schematic flowchart of a method for a wireless communication device provided by an embodiment of the present application. The wireless communication apparatus in this embodiment of the present application may be a chip or a terminal device (for example, it may be the terminal device 100 in FIG. 1 above). The chip may be a baseband chip, a communication system chip, or a group of chips including a baseband chip and a radio frequency chip. As shown in Figure 2a, the method includes:

Step S201, the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a first communication system;

Step S202, the wireless communication device performs a voice service on a second cell, and the second cell is a cell of a third communication system;

Step S203, the wireless communication device sends a first message on the second cell, where the first message is used to indicate the end of the voice service;

Step S204, the wireless communication device receives a second message on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is the third cell. 2. The cell of the communication system;

Step S205, after receiving the second message, the wireless communication device searches for a cell of the first communication system before attempting to access the third cell, and attempts to access the first communication system when a suitable cell of the first communication system is found system area.

In step S205, "searching for a suitable cell of the first communication system" may also be understood as searching for a cell of the first communication system that satisfies a preset condition. The preset conditions may include various situations, for example, the signal strength of the cell of the first communication system may be greater than a preset signal strength threshold, etc. These preset conditions may refer to relevant standard protocols, such as relevant technical specifications of 3GPP.

It can be seen from the related content of steps S201 to S205 that when the wireless communication device falls back from the first communication system to the third communication system to perform the voice service, and after the voice service ends on the third communication system, although the network device The second message indicates that the terminal device is redirected to the second communication system, but the wireless communication system does not directly attempt to access the cell of the second communication system after receiving the second message, but first attempts to access the cell of the first communication system. community. Compared with the solution in which the wireless communication device first accesses the cell of the second communication system and then accesses the cell of the first communication system after receiving the second message, the solution shown in FIG. 2a can make the terminal device return to the first communication system more quickly. a communication system.

In a possible implementation manner, after step S205, it further includes at least one of step S206 and step S207:

Step S206, after the wireless communication apparatus successfully accesses the cell of the first communication system, the wireless communication apparatus performs data service in the cell of the first communication system. In this case, the cell under the 4G communication system can no longer be searched, that is, no attempt is made to access the third cell.

In step S206, after the wireless communication device successfully accesses the cell of the first communication system, the cell of the first communication system may perform voice service in addition to data service.

Step S207, the wireless communication device attempts to access the third cell after the access to the cell of the first communication system fails.

It can be seen from steps S206 and S207 that when the wireless communication device falls back from the first communication system to the third communication system to perform the voice service, and ends the voice service on the third communication system, it first attempts to access the first communication system If the cell is successful, the data service or voice service is performed in the first communication system, and if it fails, it is redirected to the second communication system according to the second message. Compared with the solution in which the wireless communication device first accesses the cell of the second communication system and then accesses the cell of the first communication system after receiving the second message, the solution shown in FIG. 2a can make the terminal device return to the first communication system more quickly. a communication system.

In a possible implementation manner, the standard priority of the first communication system is higher than that of the second communication system, and the standard priority of the second communication system is higher than that of the third communication system.

In the embodiments of the present application, the first communication system is a 5G communication system, the second communication system is a 4G communication system, and the third communication system is a 2G communication system or a 3G communication system as an example for description. In this case, Fig. 2b exemplarily shows a schematic flowchart of another method for a wireless communication device provided by an embodiment of the present application. As shown in Fig. 2b, the method includes:

Step S211, the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a 5G communication system;

Step S212, the wireless communication device performs a voice service on a second cell, and the second cell is a cell of a 2G communication system or a 3G communication system;

Step S213, the wireless communication device sends a first message on the second cell, where the first message is used to indicate the end of the voice service;

Step S214, the wireless communication device receives a second message on the second cell, the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is 4G a cell of a communication system;

Step S215, after receiving the second message, the wireless communication device searches for a cell of the 5G communication system before attempting to access the third cell, and attempts to access the 5G cell when a suitable 5G cell is found.

In a possible implementation manner, after step S215, it further includes at least one of steps S216 and S217:

Step S216, after the wireless communication device successfully accesses the 5G cell, performs data service in the 5G cell.

In step S216, after the wireless communication device successfully accesses the 5G cell, it can perform other services in the 5G cell, such as voice services, etc. If the 5G cell does not support voice services, it can fall back to other communication systems to continue voice services. .

Step S217, after the wireless communication device fails to access the 5G cell, it attempts to access the third cell.

It can be seen from the related content of Figure 2b that when the wireless communication device falls back from the 5G communication system to the 2G communication system or the 3G communication system to perform the voice service, and after the voice service ends, although the network device instructs the terminal device to redirect to the 4G communication system However, the wireless communication system does not directly try to access the cell of the 4G communication system, but first tries to access the cell of the 5G communication system. Compared with the solution in which the wireless communication device first accesses the cell of the 4G communication system and then accesses the cell of the 5G communication system, the solution shown in FIG. 2a can make the terminal device return to the 5G communication system more quickly.

In the above-mentioned step S201, the wireless communication device initiates a voice service in the first cell. Specifically, the wireless communication device may be the calling party or the called party.

In a possible implementation, the wireless communication device may be the calling party. In this case, the wireless communication device may send a session invitation message on the first cell based on a trigger of a user operation, and the session invitation message is used to initiate a voice call business.

Fig. 3a exemplarily shows a flowchart of a method for initiating a voice service when the wireless communication device is the calling party. In FIG. 3a , the wireless communication device is the terminal device 100 in FIG. 1 , and the wireless communication device initiates a voice call to other wireless communication devices (such as the terminal device 104 ) as an example for illustration.

S300, the terminal device 100 resides in a cell under the 5G communication system.

S301, the terminal device 100 receives a user operation for triggering step S302.

S302, the terminal device 100 initiates a session invitation message to the IMS.

The session invitation message in this embodiment of the present application may be IMS_SIP_OUTGOING (sip_invite). The session invitation message is used to initiate a voice service.

S303, the terminal device 100 sends a service request to the network device under the 5G communication system.

The network device under the 5G communication system may be the access network device or the core network device under the 5G communication system, for example, the 5GC mentioned in the foregoing content.

The service request in this embodiment of the present application may be a service request (voice call). The service request is used to request the network equipment of the 5G communication system to provide VoNR services.

S304, the terminal device 100 sends a radio resource control (Radio Resource Control, RRC) connection establishment request to the network device under the 5G communication system.

The RRC connection establishment request in the embodiment of the present application may be a connection establishment request RRC setup request. In a possible implementation, the RRC connection establishment request under NR may also be written as RRC NR connection request. Among them, NR is the abbreviation of New Radio (New Radio, NR).

S305 , after receiving the RRC connection establishment request, the network device under the 5G communication system sends an RRC connection establishment response to the terminal device 100 .

The RRC connection establishment response in this embodiment of the present application may be the connection establishment RRC setup. In a possible implementation manner, the RRC connection setup response under NR may also be written as RRC NR connection setup.

S306, the terminal device 100 sends an RRC connection establishment completion message to the network device under the 5G communication system.

The RRC connection establishment complete message in the embodiment of the present application may be RRC setup complete. In a possible implementation, the RRC connection setup complete message under NR can also be written as RRC NR connection setup complete.

S307 , the network device under the 5G communication system sends a service acceptance message to the terminal device 100 .

The service accept message in this embodiment of the present application may be service accept.

S301 to S307 in FIG. 3a above exemplarily show the process of initiating a voice call through VoNR by the terminal device 100 as the calling party.

In a possible implementation, the wireless communication apparatus may be the called party. In this case, other wireless communication apparatuses (eg, terminal equipment 104 ) initiate a call to the wireless communication apparatus (eg, terminal equipment 100 ), and other wireless communication apparatuses (eg, terminal equipment 100 ) initiate a call. After the device (eg, terminal device 104) initiates a session invitation, the network device sends a paging message to the wireless communication device, and the wireless communication device receives the paging message on the first cell, where the paging message is used to instruct the wireless communication device to initiate a voice service. It can also be understood that the paging message is used to indicate that the wireless communication device has other wireless communication devices that initiate a voice service to it.

Fig. 3b exemplarily shows a flowchart of a method for initiating a voice service when the wireless communication device is the called party. In FIG. 3 b , the wireless communication device is the terminal device 100 in FIG. 1 , and other wireless communication devices (such as the terminal device 104 ) initiate a voice call to the terminal device 100 as an example for illustration.

S311, the terminal device 100 receives a paging message from a network device under the 5G communication system.

The paging message in this embodiment of the present application may be RRC (paging (voice call)).

S312, the terminal device 100 sends a service request to the network device under the 5G communication system.

S313, the terminal device 100 sends a radio resource control (Radio Resource Control, RRC) connection establishment request to the network device under the 5G communication system.

For a related description of the RRC connection establishment request in the embodiment of the present application, reference may be made to the description of the foregoing content, and details are not repeated here.

S314 , after receiving the RRC connection establishment request, the network device under the 5G communication system sends an RRC connection establishment response to the terminal device 100 .

For a related description of the RRC connection establishment response in this embodiment of the present application, reference may be made to the description of the foregoing content, and details are not repeated here.

S315, the terminal device 100 sends an RRC connection establishment completion message to the network device under the 5G communication system.

For a related description of the RRC connection establishment complete message in the embodiment of the present application, reference may be made to the description of the foregoing content, and details are not repeated here.

S316 , the network device under the 5G communication system sends a service acceptance message to the terminal device 100 .

S311 to S316 in the above FIG. 3b exemplarily show the process of initiating a voice call through VoNR by the terminal device 100 as the called party.

In the above step S202, the wireless communication device falls back from the first communication system to the third communication system to perform the voice service. There are many ways for the wireless communication device to fall back from the first communication system to the third communication system, such as the way a1 and the way a2.

Manner a1: The wireless communication device first falls back from the first communication system to the second communication system, and then falls back from the second communication system to the third communication system.

In the manner a2, the wireless communication device falls back from the first communication system to the third communication system.

That is to say, in the manner a2, the wireless communication device no longer first falls back from the first communication system to the second communication system, and then falls back from the second communication system to the third communication system. Rather, it falls directly from the first communication system to the third communication system.

In the above manners a1 and a2, there are various manners for the wireless communication device to fall back from one communication system to another communication system, for example, the following manners b1 and b2.

In the mode b1, the wireless communication device falls back from one communication system to another communication system based on the mode of actively changing cells.

For example, when the wireless communication device fails to initiate a voice service in the first communication system, it can search for the second communication system through a public land mobile network (Public Land Mobile Network, PLMN) selection process, a cell selection process, or a cell reselection process, etc. frequency on the second communication system, thereby attempting to access the frequency on the second communication system. After the voice service fails to be initiated on the second communication system, the frequency point on the third communication system can be searched through the PLMN selection process, the cell selection process or the cell reselection process, etc., so as to try to access the third communication system. Frequency.

For another example, after the wireless communication device fails to initiate a voice service in the first communication system, it can search for a frequency point on the third communication system through the PLMN selection process, the cell selection process or the cell reselection process, etc., so as to try to access the third communication system. Frequency points on the communication system.

In a possible implementation manner, the wireless communication apparatus falls back from the first communication system to the third communication system based on the way of actively changing cells. Specifically, after the wireless communication device initiates the voice service in the first cell and before the voice service is continued in the second cell, the wireless communication device may access the second cell based on the method of actively changing cells.

In a possible implementation manner, the wireless communication device finds that the voice service fails to be initiated, and actively selects a cell with a lower standard to access, so as to perform the voice service again.

In manner b2, the wireless communication apparatus falls back from one communication system to another communication system according to the instruction of the network device.

In a possible implementation manner, the wireless communication apparatus falls back from the first communication system to the third communication system according to the instruction of the network device. In a possible implementation manner, after the first cell initiates the voice service and before the second cell performs the voice service, the method further includes: the wireless communication device receives an air interface message from the base station, where the air interface message is used to instruct the wireless communication device Access the second cell.

It can be seen that the main difference between the mode b1 and the mode b2 is that in the mode a1, the wireless communication device actively switches to the cell of the communication system of the lower standard, so as to perform the voice service again. In the mode a2, the network device judges that the voice service has failed to be initiated, and instructs the wireless communication device to switch to a cell of a communication system of a lower standard, so as to perform the voice service again.

When the wireless communication device needs to first fall back from the first communication system to the second communication system, and then fall back from the second communication system to the third communication system, that is, the solution mentioned in the above solution a1, in this case, there are the following Several possible situations:

The first communication system falls back from the first communication system to the second communication system based on the way of actively changing cells, and then falls back from the second communication system to the third communication system based on the way of actively changing cells;

The first communication system falls back from the first communication system to the second communication system according to the instruction of the network equipment, and then falls back from the second communication system to the third communication system according to the instruction of the network equipment;

The first communication system falls back from the first communication system to the second communication system based on the way of actively changing cells, and then falls back from the second communication system to the third communication system according to the instruction of the network device;

The first communication system falls back from the first communication system to the second communication system according to the instruction of the network device, and then falls back from the second communication system to the third communication system based on the way of actively changing cells.

FIG. 3c exemplarily shows a schematic flowchart of a method for a wireless communication apparatus to fall back from a first communication system to a third communication system. In FIG. 3c, the above-mentioned manner a1 and manner b2 are applied for presentation. The steps of FIG. 3c may be combined with the steps of FIG. 3a or FIG. 3b. For example, step S321 may be performed after step S307, or step S321 may be performed after step S316.

In a possible implementation manner, the wireless communication apparatus may fall back from the 5G communication system to the 4G communication system by means of Handover (handover), Redirection (redirection), etc. according to the instruction of the network device. Among them, the EPS Fallback based on the Redirection method falls back. After the terminal falls back to the 4G communication system, it needs to read the 4G side system message, and then establish the VoLTE service. If there is data service before the EPS Fallback, the bearer can also be re-established on the LTE side to Restoring data services. For the process of falling back from the 5G communication system to the 4G communication system, reference may be made to steps S321 to S328 involved in FIG. 3c below.

As shown in Figure 3c, the method includes:

S321, the network device under the 5G communication system recognizes that the VoNR call is not supported, and triggers step S322, so as to redirect to the cell under the 4G communication system.

S322 , the network device under the 5G communication system sends a switching instruction to the terminal device 100 .

In the embodiment of the present application, the handover instruction in S322 may be a mobility from NR command, an RRC connection release message, or an RRC Connection Release message.

The network device under the 5G communication system may carry the frequency point of the target LTE, multiple target cell IDs, system messages of the target cell, and the like in the handover instruction in S322. In a possible implementation manner, the frequency point of the third cell in the embodiment of the present application is also carried in the handover instruction in S322. The switching instruction in S322 instructs the terminal device 100 to perform redirection, and can initiate the S1 terminal device context release process. In another possible implementation manner, the handover instruction may also contain information about other cells under the 4G communication system except the third cell, and the cell may be on the same frequency as the third cell or on a different frequency.

In a possible implementation manner, the information of the cell carried in the handover instruction may be information such as the frequency point of the cell.

S323, the terminal device 100 receives the system message sent by the network device under the 4G communication system.

In this embodiment of the present application, the system message in S323 may be system information. For example, system messages may be received by receiving broadcast messages.

In the embodiment of the present application, the system message may include the frequency of the resident cell, the frequency band, the Public Land Mobile Network (PLMN), the physical cell identification (Identification, ID), the bandwidth, the discontinuous reception (discontinuous Reception) , DRX) cycle and other information.

S324, the terminal device 100 sends a tracking area update (Tracking Area Update, TAU) request to the network device under the 4G communication system.

S325, the network device under the 4G communication system sends a TAU acceptance to the terminal device 100.

In this embodiment of the present application, the TAU accept in S325 may also be a TAU accept message or a TAU accept.

S326, the terminal device 100 completes sending the TAU to the network device under the 4G communication system.

In this embodiment of the present application, the TAU complete in S326 may also be a TAU complete message or a TAU complete.

S327, the terminal device 100 sends a bearer establishment request to the network device under the 4G communication system.

In this embodiment of the present application, the bearer establishment request in S327 may be activatededicatedepsbearercontextrequest.

S328 , the network device under the 4G communication system sends a bearer establishment acceptance to the terminal device 100 .

In this embodiment of the present application, the bearer establishment acceptance in S328 may be Bearer context accept.

S329, the IMS fails to send the service to the terminal device 100.

In the embodiment of the present application, the IMS in S329 indicates through signaling that the voice service call fails, indicating that the service is unavailable. Service failure can be sip/2.0 503 service unavailable, possibly, the message can be a sip message request rejected because the service is unavailable.

After receiving the service failure sent by the IMS through S329, the terminal device 100 can switch to the CS domain to try to perform the voice service. The signaling sent in step S330 is used to trigger redirection.

S330, the terminal device 100 sends an extended service request to the network device under the 4G communication system.

In this embodiment of the present application, the extended service request in S330 may be an Extended Service Request, which may be a NAS message. Through step S330, a network device (for example, an MME) under the 4G communication system may be notified to initiate a CS domain service.

The above steps S322 to S330 can show the process of the terminal device 100 falling back from the 5G communication system to the 4G communication system to perform the voice service. After receiving S329, the terminal device 100 determines that the voice service cannot be performed in the 4G communication system, then Step S331 is triggered through S330 to redirect to a cell under the 2G or 3G communication system.

S331 , the network device under the 4G communication system switches the instruction to the terminal device 100 .

In a possible implementation manner, through the above step S330, the terminal device 100 notifies the network device (eg, MME) under the 4G communication system to initiate the CS domain service, and further, the network device (eg, the MME) under the 4G communication system. A network device (such as an eNodeB) under the 4G communication system can be instructed to trigger the CSFB process through the S1-AP Request message. Optionally, if the MME supports the location area identity (Location Area Identity, LAI) feature, it simultaneously delivers the LAI to the eNodeB. The eNodeB can decide whether to start blind handover according to the terminal device capability, configuration parameters and algorithm strategy.

In this embodiment of the present application, the handover instruction in S331 may be a mobility from NR command, an RRC connection release message, or an RRC Connection Release message.

The handover instruction may carry information of cells under the 2G or 3G communication system. In a possible implementation manner, the handover instruction may carry information of the second cell, so that the terminal device 100 is redirected to the second cell.

In a possible implementation manner, the information of the second cell may be information such as frequency points of the second cell.

The handover instruction in S331 of a network device (such as an eNodeB) under the 4G communication system may carry the frequency point of the target UTRAN, multiple target cell IDs, system messages of the target cell, and so on. The frequency of the second cell in the embodiment of the present application is also carried in the handover instruction in S331. The switching instruction in S331 instructs the terminal device 100 to perform redirection, and can initiate the S1 terminal device context release process.

S332, the terminal device 100 receives the system message sent by the network device under the 2G or 3G communication system.

S333, the terminal device 100 sends a location update request to the network device under the 2G or 3G communication system.

In this embodiment of the present application, the location update request in S333 may be a location update request.

S334, the network device under the 2G or 3G communication system sends a location update acceptance to the terminal device 100.

In this embodiment of the present application, the location update request in S334 may be location update accept.

The above steps S333 and S334 can show the location update process of the CS domain under the GU under GSM and WCDMA. Optionally, the terminal device may initiate LA update, or joint RA/LA update, or both LA and RA update at the target cell. Among them, RA is the abbreviation of routing area, and LA is the abbreviation of location area.

S335, the terminal device 100 sends a CM service request to the network device under the 2G or 3G communication system.

In this embodiment of the present application, the CM service request in S335 may be a CM service request.

Through the above steps S331 to S335, the process of the terminal device 100 falling back from the 4G communication system to the 2G or 3G communication system for voice service can be shown, and the service request of the CM layer can be initiated through step S335.

The following steps S336 to S344 describe an example of the process of establishing, proceeding and hanging up a possible call process.

S336, the terminal device 100 sends the NAS call setup to the network device under the 2G or 3G communication system.

In this embodiment of the present application, the NAS call setup in S336 may be NAS CC setup.

S337, the network device under the 2G or 3G communication system sends the NAS call process to the terminal device 100.

In this embodiment of the present application, the NAS calling process in S337 may be NAS CC call proceeding.

S338, the network device under the 2G or 3G communication system sends the NAS call ringing to the terminal device 100.

In this embodiment of the present application, the NAS call ringing in S338 may be NAS CC call alerting.

S339, the network device under the 2G or 3G communication system sends the terminal device 100 the related process of the supplementary service in the NAS call process.

In the embodiment of this application, the related process of the supplementary service in the NAS call process in S339 may also be referred to as the supplementary service interaction process in the call process, which may be the NAS CC call facility, and this part of the signaling may be: the network sends a request to the terminal device Or confirm the supplementary service request, wherein the supplementary service request may be included in the message IE.

S340, the network device under the 2G or 3G communication system sends the NAS call connection to the terminal device 100.

In this embodiment of the present application, the NAS call connection in S340 may be a NAS CC call connect.

S341, the terminal device 100 sends a NAS call connection confirmation to the network device under the 2G or 3G communication system.

In this embodiment of the present application, the NAS call connection confirmation in S341 may be a NAS CC call connect ack.

S342, the terminal device 100 sends a call hang-up message to the network device under the 2G or 3G communication system after receiving the user's operation of hanging up the phone.

It can be seen from the above example that in this embodiment of the present application, the call hang-up message is used to indicate the end of the voice service.

In the embodiment of the present application, the S342 call hangup message may also be the NAS call connection disconnection, or the NAS CC disconnection.

S343, the network device under the 2G or 3G communication system sends the NAS call release to the terminal device 100.

In this embodiment of the present application, the NAS call release in S343 may be a NAS CC release.

S344, the terminal device 100 sends a NAS call release confirmation to the network device under the 2G or 3G communication system.

In this embodiment of the present application, the NAS call release confirmation in S344 may be NAS CC release complete.

S345, the network device under the 2G or 3G communication system sends a connection release message to the terminal device 100.

In the embodiment of this application, the connection release message in S345 may also be called channel release, or may be channel release (eUteranDesc).

In the above step S203 of FIG. 2a, the first message is used to indicate the end of the voice service, that is, the wireless communication device will send the first message to notify the network after receiving the voice service. In a possible implementation manner, the first message may be the call hang-up message in the foregoing step S342. In another possible implementation manner, the first message may be the NAS call release confirmation in the foregoing step S344.

In the above step S204 of FIG. 2a, the second message may carry the information of the third cell. The information of the third cell may also not be carried. In this embodiment of the present application, the information of the third cell may be information such as a frequency point of the third cell. The second message is used to instruct the wireless communication device to redirect to the third cell.

In a possible implementation manner, the second message may be the connection release message in the foregoing step S345. In a possible implementation manner, when the second message carries information such as the frequency of the third cell, the "eUtranDesc->nest->arcfn" field in the connection release message can be used to carry the frequency of the third cell. point information.

In the above step S205 of FIG. 2a, after receiving the second message, the wireless communication device searches for a cell of the first communication system before attempting to access the third cell, and when a suitable cell of the first communication system is found, An attempt is made to access a cell of the first communication system.

In a possible implementation manner, the attempt to access the cell of the first communication system includes: sending a connection establishment request on the cell of the first communication system, where the connection establishment request is used to request to establish a wireless connection with the cell of the first communication system . When the first communication system is a 5G communication system, attempting to access the cell of the first communication system includes: sending a connection establishment request on the 5G cell, where the connection establishment request is used to request to establish a wireless connection with the 5G cell.

Fig. 3d exemplarily shows a schematic flow chart of the above-mentioned method from steps S205 to S207, and Fig. 3d may be combined with the foregoing content, for example, may be combined with the content of Fig. 3c. When FIG. 3d is combined with the content of FIG. 3c, the second message can be the connection release message in the above step S345 as an example for introduction, and the step S346 can be executed after the above step S345.

The content shown in Figure 3d will be introduced below. As shown in Figure 3d, the method includes:

S346, the terminal device searches for the frequency point of the 5G communication system.

In the above step S205, after receiving the second message, the wireless communication device attempts to access the third cell.

The terminal equipment searches for cells of the first communication system, including searching for the first cell. In a possible implementation manner, the frequency point of the first cell may be searched, and the search result may include at least one of the first cell and an intra-frequency cell of the first cell. It is also possible that the search result does not include the first cell, nor does it include the same-frequency cell of the first cell, that is, the frequency point of the first cell is searched, and no cell may be found.

In a possible implementation manner, after searching for the first cell and/or an intra-frequency cell of the first cell, an attempt may be made to access a searched cell. Taking searching for the first cell and attempting to access the first cell as an example, the process of the terminal device attempting to access the first cell is schematically introduced. For example, the following steps may be included:

S3471, the terminal device 100 receives a system message from a network device under the 5G communication system.

S3472, the terminal device initiates a radio link establishment request in the first cell.

The wireless link establishment request is used to request to establish a wireless link with a network device under the 5G communication system.

S3473, the network device sends a wireless link establishment success message to the terminal device.

When the network device determines that the establishment of the wireless link is successful, a wireless link establishment success message is sent to the terminal device through step S3473. When the network device determines that the establishment of the wireless link fails, the wireless link establishment failure message is sent to the terminal device through step S3473.

S3474, the terminal device sends a wireless link establishment completion message.

After the terminal device receives the wireless link establishment success message through S3474, after the wireless link establishment is completed, it can send the wireless link establishment complete message to the network device through step S3474.

S3475, the terminal device 100 sends a registration request to the network device under the 5G communication system.

When a wireless link is established between the terminal device and the network device under the 5G communication system through steps S3471 to S3474, a registration request can be sent through step S3475.

S3476, the network device under the 5G communication system sends a registration acceptance to the terminal device 100.

When the network device under the 5G communication system determines to accept the registration request of the terminal device 100 , it returns the registration acceptance to the terminal device 100 . When the network device under the 5G communication system determines not to accept the registration request of the terminal device 100 , it does not return registration acceptance to the terminal device 100 , or may return registration failure to the terminal device 100 .

S3477, the terminal device sends the registration completion to the network device.

After the terminal device receives the registration acceptance message through step S3476, it can return the registration completion to the network device after the registration is completed, thereby completing the registration on the network device under the 5G communication system.

In this embodiment of the present application, if the registration acceptance in S3476 is used to indicate that the terminal device is successfully registered, it means that the terminal device successfully accesses the 5G cell.

In this embodiment of the present application, there are various ways to determine that the terminal equipment fails to access the 5G cell. For example, the registration acceptance in the above step S3476 may be used to indicate that the terminal equipment fails to register, which means that the terminal equipment fails to access the first cell. . It may also be that when the terminal device initiates a radio link establishment request in the first cell, the received radio link establishment failure message indicates that the terminal device connection establishment failed. fail. It may also include that, as mentioned in the foregoing content, if the frequency point of the first cell is searched and the first cell is not found, it can also be said that the terminal device fails to access the first cell.

In a possible implementation manner, if the terminal device fails to access the first cell, it means that the first cell is unavailable. If the terminal device successfully accesses the first cell, it indicates that the first cell is available.

In a possible implementation, when the first cell is unavailable, a historical cell of the first communication system is searched. In a possible implementation manner, searching for the historical cells of the first communication system includes searching for frequency points of the historical cells of the first communication system.

Assuming that the first communication system is a 5G communication system cell, with reference to FIG. 3d, in the above step S346, the terminal device may first search for the first cell. In a possible implementation manner, the frequency point of the first cell may be searched, and the search result may include the first cell and an intra-frequency cell of the first cell. In a possible implementation, when the first cell is unavailable, the historical cells of the 5G communication system are searched. In a possible implementation manner, searching for the historical cells of the 5G communication system includes searching for frequency points of the historical cells of the 5G communication system.

Through the above steps S346 to S3476, the terminal device may be connected to a cell of the 5G communication system, or may not be connected to a cell of the 5G communication system, as shown in Figure 3d, the method further includes step S351:

S351 , if the terminal device successfully accesses the cell under the 5G communication system, the terminal device can perform services under the 5G communication system.

If the terminal device fails to access the cell under the 5G communication system, the terminal device can access the 4G communication system.

In the embodiments of the present application, there may be various ways for the terminal device to access the 4G communication system, and the following will introduce the ways c1 and c2.

In the manner c1, the information of the third cell is included in the second message.

When the second message can be the connection release message in the above step S345, it can be said that the connection release message in the above S345 includes the information of the third cell, such as the frequency of the third cell and other information. In this case, the terminal device can search for the frequency point of the third cell according to the second message, so that the terminal device can quickly reselect (Fast Return) back to the 4G communication system and avoid staying in the 2G/3G communication system.

Mode c2, the information of the third cell is not included in the second message.

In this case, the terminal can try to return to 4G by itself without relying on the network. For example, the terminal device tries to return to the 4G network according to the 4G network information previously measured by the mobile phone. In a possible implementation manner, the terminal device supporting autonomous FR starts energy measurement of the LTE cell at the current location during the voice call, and obtains the cell and quality information of the 4G network at the current location. If the network-delivered measurement information (Measurement Information) message includes LTE neighbor cell information, the LTE neighbor cell delivered by the network is prioritized for energy measurement. The terminal equipment records the LTE cells that exceed a certain energy threshold during the measurement process (the threshold is configurable).

When the terminal device needs to access the 4G communication system, if the LTE frequency cell information exceeding the threshold is previously found, the information is used to initiate redirection to LTE. If no LTE cell exceeding the threshold is measured before, it still resides on the current 2G or 3G network, and then returns to the LTE or NR communication system by other means.

As shown in Figure 3d, steps S352 to S356 show a schematic flowchart of a method for the terminal device 100 to attempt to access the 4G communication system. As shown in Figure 3d, when it is determined in step S351 that the terminal device fails to access the 5G For a cell under the communication system, step S352 may be executed.

S352, the terminal device 100 receives the system message sent by the network device under the 4G communication system.

In this embodiment of the present application, the system message in S352 may be system information. For example, system messages may be received by receiving broadcast messages.

S353, the terminal device 100 sends a tracking area update (Tracking Area Update, TAU) request to the network device under the 4G communication system.

S354, the network device under the 4G communication system sends a TAU acceptance to the terminal device 100.

In the embodiment of the present application, the TAU accept in S354 may also be a TAU accept message or a TAU accept.

S355, the terminal device 100 completes sending the TAU to the network device under the 4G communication system.

In this embodiment of the present application, the TAU complete in S355 may also be a TAU complete message or a TAU complete.

S356, the terminal device 100 sends an RRC connection establishment request to the network device under the 4G communication system.

In a possible implementation manner, the above step S205 may further include a judgment condition, for example, after the wireless communication device tries to access the third cell after receiving the second message, when it determines that the first preset condition is satisfied When the first communication system cell is searched, and when a suitable first communication system cell is found, try to access the first communication system cell. The first preset condition may be "whether the signal strength of the first cell recorded when the terminal device initiates a call is greater than a preset signal strength threshold". In this possible implementation, when the terminal device is the calling party, the terminal device can record the signal strength of the first cell when the call is initiated (such as sending a session invitation message). When the terminal device is the called party, the terminal device The signal strength of the first cell may be recorded when a call is initiated (eg, a paging message is received).

Based on the above content, FIG. 4a exemplarily shows a schematic flowchart of a method for a wireless communication device provided by an embodiment of the present application. As shown in Figure 4a, the method includes:

Step S401, initiating a voice service in a first cell, where the first cell is a cell of a first communication system. For this step, reference may be made to the relevant description of the foregoing step S201.

In step S402, the voice service is performed on the second cell, and the second cell is a cell of the third communication system. For this step, reference may be made to the relevant description of the foregoing step S202.

Step S403: Send a first message on the second cell, where the first message is used to indicate the end of the voice service. For this step, reference may be made to the relevant description of the foregoing step S203.

Step S404, receiving a second message on the second cell, where the second message is used to instruct the wireless communication device to redirect to a third cell, where the third cell is a cell of the second communication system. For this step, reference may be made to the relevant description of the foregoing step S204.

Step S405, after receiving the second message, try to access the third cell; when receiving the wireless connection release message on the third cell, search for the cell of the first communication system, and search for a suitable first communication system cell. When it is a cell, try to access the cell of the first communication system.

Taking the first communication system as a 5G communication system, the second communication system as a 4G communication system, and the third communication system as a 2G communication system or a 3G communication system as an example, the above step S405 can be written as:

After receiving the second message, try to access the third cell; when receiving the wireless connection release message on the third cell, search for the cell of the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell .

Different from the related content of the aforementioned FIG. 2a, in the aforementioned FIG. 2a, in step S205, after receiving the second message, the wireless communication device performs the action based on the response to the second message: to the cell of the 5G communication system. to search. However, in FIG. 4a, after receiving the second message, the wireless communication apparatus performs an action based on the response to the second message: attempt to access the third cell. And when the wireless connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

In one possible implementation, the wireless communication device searches for a cell of the first communication system in response to the wireless connection release message. In this case, the wireless connection release message may carry a 5G message. However, if there is no cell of the first communication system in the wireless connection release message, the wireless communication device will also search for a cell of the first communication system after receiving the wireless connection release message.

It can be seen from the content of FIG. 4a that after the terminal device falls back to the second communication system, after receiving the wireless connection release message, the frequency point of the first communication system can be searched. In a possible implementation, the terminal After the device falls back to the second communication system, it searches for the frequency point of the first communication system when entering the idle state. Compared with the solution in which the terminal device performs cell replacement only when the signal quality of the currently camped cell is found to be poor, the speed at which the terminal device returns to the first communication system can be accelerated.

In the above step S405, after the terminal device receives the second message, the second message may include the information of the third cell, or may not include the information of the third cell. In these two cases, for the manner in which the terminal device accesses the cell under the 4G communication system, reference may be made to the introduction of the foregoing manners c1 and c2, and details are not described herein again.

FIG. 4b is an exemplary schematic flowchart of the method of the above step S405, and FIG. 4b may be combined with the foregoing content, for example, may be combined with the content of FIG. 3c. When FIG. 4b is combined with the content of FIG. 3c, the second message may be the connection release message in the above step S345 as an example for description, and step S361 may be executed after the above step S345.

The content shown in Figure 4b will be introduced below. As shown in Figure 4b, the method includes:

S361, the terminal device 100 receives a system message sent by a network device under the 4G communication system.

S362, the terminal device 100 sends a tracking area update (Tracking Area Update, TAU) request to the network device under the 4G communication system.

S363, the network device under the 4G communication system sends a TAU acceptance to the terminal device 100.

S364, the terminal device 100 completes sending the TAU to the network device under the 4G communication system.

S365, the network device under the 4G communication system sends an RRC connection release message to the terminal device 100.

Step S3711 is triggered by the RRC connection release message in step S362.

S3711, the terminal device searches for the frequency point of the 5G communication system.

For the related introduction of the specific search in this step, please refer to the aforementioned step S346.

S3712, the terminal device 100 receives a system message from a network device under the 5G communication system. For this step, reference may be made to the relevant description of the foregoing step S3471.

S3713, the terminal device initiates a radio link establishment request in the first cell. For this step, reference may be made to the relevant description of the foregoing step S3472.

S3714, the network device sends a wireless link establishment success message to the terminal device. For this step, reference may be made to the relevant description of the foregoing step S3473.

S3715, the terminal device sends a wireless link establishment complete message. For this step, reference may be made to the relevant description of the foregoing step S3474.

S3716, the terminal device 100 sends a registration request to the network device under the 5G communication system. For this step, reference may be made to the relevant description of the foregoing step S3475.

S3717, the network device under the 5G communication system sends a registration acceptance to the terminal device 100. For this step, refer to the relevant description of the aforementioned step S3476.

S3718, the terminal device sends the registration completion to the network device. For this step, refer to the relevant description of the aforementioned step S3477.

In a possible implementation, in the above step S405, a judgment condition may also be included, for example, after receiving the second message, try to access the third cell; when it is determined that the first preset condition is satisfied, in the third When a radio connection release message is received on the cell, it searches for a cell of the first communication system, and when a suitable cell of the first communication system is found, attempts to access the cell of the first communication system. For the first preset condition, reference may be made to the description of the foregoing content, and details are not repeated here.

Based on the above content, FIG. 5a exemplarily shows a schematic flowchart of a method for a wireless communication device provided by an embodiment of the present application. As shown in Figure 5a, the method includes:

Step 501, the wireless communication device initiates a voice service in a first cell, where the first cell is a cell of a first communication system. For this step, reference may be made to the relevant description of the foregoing step S201.

Step 502, the wireless communication device performs a voice service on a second cell, which is a cell of the third communication system. For this step, reference may be made to the relevant description of the foregoing step S202.

Step 503, the wireless communication device sends a first message on the second cell, where the first message is used to indicate the end of the voice service. For this step, reference may be made to the relevant description of the foregoing step S203.

Step 504, the wireless communication apparatus receives a third message on the second cell, where the third message is used to instruct the wireless communication apparatus to redirect to a fourth cell, and the fourth cell is a cell of the first communication system.

Step 505: After receiving the third message, the wireless communication device attempts to access the fourth cell.

In a possible implementation manner, in FIG. 5a, the first communication system is a 5G communication system, the second communication system is a 4G communication system, and the third communication system is a 2G communication system or a 3G communication system.

In the embodiment of the present application, the fourth cell refers to a cell under a first communication system. The fourth cell may be the first cell, and the fourth cell may also be a cell under the first communication system other than the first cell.

Fig. 5b is an exemplary schematic flow chart of the method of the above step S505, and Fig. 5b may be combined with the foregoing content, for example, may be combined with the content of Fig. 3c. When FIG. 5b is combined with the content of FIG. 3c, the third message may be the connection release message in the above step S345 as an example for introduction, and step S3811 may be executed after the above step S345.

The content shown in Figure 5b will be introduced below. As shown in Figure 5b, the method includes:

S3811, the terminal device searches for the frequency point of the 5G communication system.

S3812, the terminal device 100 receives a system message from a network device under the 5G communication system. For this step, reference may be made to the relevant description of the foregoing step S3471.

S3813, the terminal device initiates a radio link establishment request in the first cell. For this step, reference may be made to the relevant description of the foregoing step S3472.

S3814, the network device sends a wireless link establishment success message to the terminal device. For this step, reference may be made to the relevant description of the foregoing step S3473.

S3815, the terminal device sends a wireless link establishment completion message. For this step, reference may be made to the relevant description of the foregoing step S3474.

S3816, the terminal device 100 sends a registration request to the network device under the 5G communication system. For this step, reference may be made to the relevant description of the foregoing step S3475.

S3817, the network device under the 5G communication system sends a registration acceptance to the terminal device 100. For this step, refer to the relevant description of the aforementioned step S3476.

S3818, the terminal device sends the registration completion to the network device. For this step, refer to the relevant description of the aforementioned step S3477.

In a possible implementation manner, in the foregoing step 505, after the wireless communication device receives the third message, it may be understood that the third message is a trigger message that triggers the wireless communication device to be redirected to the first communication system.

In a possible implementation manner, the third message may include the information of the fourth cell, or may not include the information of the fourth cell. When the third message includes the information of the fourth cell, the information of the fourth cell may be carried in the "nrDesc->nest->arfcn" field in the third message.

When the information of the fourth cell is included in the third message, the wireless communication device may preferentially attempt to access the fourth cell. In the above step S3811, the wireless communication device may first perform cell access according to the frequency point information included in the third message. search.

In another possible implementation manner, if the third message does not include the information of the fourth cell, in a possible implementation manner, in the above step S3811, the wireless communication device may first search for the information of the first cell. frequency point, and try to access the first cell, when the access to the first cell fails, try to search for the frequency point of the historical cell of the first communication system where the wireless communication device resides.

In another possible implementation manner, when the third message includes information of the fourth cell, and the information of the fourth cell is the frequency point of the first cell. Then, attempting to access the fourth cell includes: searching for a frequency point of the first cell, and accessing the first cell when the first cell is available. Wherein, accessing the first cell includes: sending a connection establishment request on the first cell, where the connection establishment request is used to request to establish a wireless connection with the first cell.

Further, in a possible implementation manner, after the frequency point of the first cell is searched, when the first cell is unavailable, a historical cell of the first communication system is searched. After searching the historical cells of the first communication system, the method further includes: after searching for a suitable cell of the first communication system, sending a connection establishment request on the cell of the first communication system, where the connection establishment request is used to request to establish communication with the first communication system The wireless connection of the cells of the system. After the access to the cell of the first communication system is successful, services, such as data service, voice service, etc., are performed in the cell of the first communication system. In the case that the access to the cell of the first communication system fails, an attempt to access the cell of the second communication system may be selected.

Taking the first communication system as a 5G communication system as an example, in a possible implementation manner, when the first cell is unavailable, a historical cell of the 5G communication system is searched. After searching for a suitable 5G cell, a connection establishment request is sent on the 5G cell, and the connection establishment request is used to request the establishment of a wireless connection with the 5G cell. After the 5G cell is successfully accessed, services, such as data services and voice services, are performed in the 5G cell. In the case that the access to the 5G cell fails, an attempt to access the cell under the 4G communication system can be selected.

The terms "system" and "network" in the embodiments of the present application may be used interchangeably. "At least one" means one or more, and "plurality" means two or more. "And/or", which describes the association relationship of the associated objects, indicates that there can be three kinds of relationships, for example, A and/or B, which can indicate: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A, B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one item (a) of a, b, or c can represent: a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, c may be single or multiple .

And, unless otherwise specified, ordinal numbers such as “first” and “second” mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the order, sequence, priority or importance of multiple objects degree. For example, the first cell and the second cell are only for distinguishing different cells, but do not indicate the difference in priority or importance of the two cells.

It should be noted that the names of the above-mentioned messages are only examples. With the evolution of communication technology, any of the above-mentioned messages may change their names, but no matter how the names change, as long as their meanings are the same as the meanings of the above-mentioned messages in this application , all fall within the protection scope of this application.

The foregoing mainly introduces the solution provided by the present application from the perspective of interaction between various network elements. It can be understood that, in order to realize the above-mentioned functions, each network element in the above-mentioned implementation includes corresponding hardware structures and/or software modules for executing each function. Those skilled in the art should easily realize that the present invention can be implemented in hardware or a combination of hardware and computer software in conjunction with the units and algorithm steps of each example described in the embodiments disclosed herein. Whether a function is performed by hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Skilled artisans may use different methods for implementing the described functionality for each particular application, but such implementations should not be considered beyond the scope of the present invention.

According to the foregoing method, FIG. 6a is a schematic structural diagram of a communication device provided by an embodiment of the present application. As shown in FIG. 6a, the communication device may be a wireless communication device or a network device, or may be a chip or a circuit, for example, it may be arranged in a wireless communication device. A chip or circuit of the device, for example, a chip or circuit that can be provided in a network device. The wireless communication apparatus may be the terminal device mentioned in the foregoing content, or a chip or circuit in the terminal device.

As shown in FIG. 6a, the wireless communication device may include multiple components, such as: application subsystem, memory, mass storage, baseband subsystem, radio frequency integrated circuit (RFIC) , radio frequency front end (radio frequency front end, RFFE) device, and antenna (antenna, ANT). These components may be coupled by various interconnecting buses or other electrical connections.

In Fig. 6a, ANT_1 represents the first antenna, ANT_N represents the Nth antenna, and N is a positive integer greater than 1. Tx represents the transmit path, Rx represents the receive path, and different numbers represent different paths. Each path can represent a signal processing channel. Among them, FBRx represents the feedback receiving path, PRx represents the primary receiving path, and DRx represents the diversity receiving path. HB means high frequency, LB means low frequency, both refer to the relative high and low frequency. BB stands for baseband. It should be understood that the labels and components in FIG. 6a are for illustrative purposes only, and are only used as a possible implementation manner, and the embodiments of the present application also include other implementation manners. For example, a wireless communication device may include more or fewer paths, including more or fewer components.

Wherein, the application subsystem may include one or more processors. The multiple processors may be multiple of the same type of processors, or may include a combination of multiple types of processors. In this application, the processor may be a general-purpose processor or a processor designed for a specific field. For example, the processor may be a central processing unit (CPU), a digital signal processor (DSP), or a microcontroller (MCU). The processor may also be a graphics processor (graphics processing unit, GPU), an image signal processor (image signal processing, ISP), an audio signal processor (audio signal processor, ASP), and an artificial intelligence (artificial intelligence, AI) Apply a specially designed AI processor. AI processors include, but are not limited to, neural network processing units (NPUs), tensor processing units (TPUs), and processors called AI engines.

The RF integrated circuit (including RFIC 1, and one or more optional RFIC 2) and the RF front-end device can together form the RF subsystem. According to the different receiving or transmitting paths of the signal, the radio frequency subsystem can also be divided into the radio frequency receive path (RF receive path) and the radio frequency transmit path (RF transmit path). The radio frequency receiving channel can receive the radio frequency signal through the antenna, process the radio frequency signal (such as amplifying, filtering and down-converting) to obtain the baseband signal, and transmit it to the baseband subsystem. The RF transmit channel can receive the baseband signal from the baseband subsystem, process the baseband signal (such as upconverting, amplifying and filtering) to obtain the RF signal, and finally radiate the RF signal into space through the antenna. A radio frequency integrated circuit may be referred to as a radio frequency processing chip or a radio frequency chip.

Similar to the radio frequency subsystem that mainly completes radio frequency signal processing, the baseband subsystem mainly completes the processing of baseband signals. The baseband subsystem can extract useful information or data bits from the baseband signal, or convert the information or data bits into the baseband signal to be transmitted. These information or data bits may be data representing user data or control information such as voice, text, video, etc. For example, the baseband subsystem can implement signal processing operations such as modulation and demodulation, encoding and decoding. The baseband signal processing operations are not identical for different radio access technologies, such as 5G NR and 4G LTE.

Similar to the application subsystem, the baseband subsystem may also include one or more processors. In addition, the baseband subsystem may also include one or more hardware accelerators (HACs). Hardware accelerators can be used to specifically complete some sub-functions with high processing overhead, such as data packet assembly and parsing, data packet encryption and decryption, etc. These sub-functions can also be implemented using general-purpose processors, but for performance or cost considerations, it may be more appropriate to use hardware accelerators. In the specific implementation, the hardware accelerator is mainly implemented by an application specific integrated circuit (ASIC). Of course, the hardware accelerator may also include one or more relatively simple processors, such as MCU.

The baseband subsystem may be integrated into one or more chips, which may be referred to as baseband processing chips or baseband chips. The baseband subsystem can be used as a separate chip, which can be called a modem or a modem chip. Baseband subsystems can be manufactured and sold in units of modem chips. Modem chips are also sometimes called baseband processors or mobile processors. In addition, the baseband subsystem can also be further integrated in a larger chip, manufactured and sold in a larger chip unit. This larger chip may be called a system-on-a-chip, system-on-a-chip, or system on a chip (SoC), or simply a SoC chip. The software components of the baseband subsystem can be built into the hardware components of the chip before the chip leaves the factory, or can be imported into the hardware components of the chip from other non-volatile memory after the chip leaves the factory, or can also be downloaded online through the network. and update these software components.

In addition, the wireless communication device may further include memory, such as the memory and mass storage in FIG. 6a. In addition, one or more buffers may be included in the application subsystem and the baseband subsystem, respectively. In specific implementation, memory can be divided into volatile memory (volatile memory) and non-volatile memory (non-volatile memory, NVM). Volatile memory refers to memory in which data stored inside is lost when the power supply is interrupted. At present, volatile memory is mainly random access memory (random access memory, RAM), including static random access memory (static RAM, SRAM) and dynamic random access memory (dynamic RAM, DRAM). Non-volatile memory refers to memory whose internal data will not be lost even if the power supply is interrupted. Common non-volatile memories include read only memory (ROM), optical disks, magnetic disks, and various memories based on flash memory technology. Generally speaking, memory and cache can choose volatile memory, and mass storage can choose non-volatile memory, such as flash memory.

According to the foregoing method, FIG. 6b is a schematic structural diagram of a communication device provided by an embodiment of the present application. As shown in FIG. 6b, the communication device may be a wireless communication device or a network device, or a chip or a circuit, for example, it may be arranged in a wireless communication device. A chip or circuit of the device, for example, a chip or circuit that can be provided in a network device. The wireless communication apparatus may be the terminal device mentioned in the foregoing content, or a chip or circuit in the terminal device. The communication device of FIG. 6b may be the communication device of FIG. 6a.

As shown in FIG. 6b, the communication device 1301 may include a processor 1302, and a transceiver 1303 coupled to the processor 1302. Memory 1304 may also be included.

Further, the communication device 1301 may further include a bus system, wherein the processor 1302, the memory 1304, and the transceiver 1303 may be connected through the bus system.

It should be understood that the above-mentioned processor 1302 may be a chip. For example, the processor 1302 may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), or a system on chip (SoC). It can be a central processing unit (CPU), a network processor (NP), a digital signal processing circuit (DSP), or a microcontroller (microcontroller). unit, MCU), it can also be a programmable logic device (PLD) or other integrated chips.

In the implementation process, each step of the above-mentioned method can be completed by an integrated logic circuit of hardware in the processor 1302 or an instruction in the form of software. The steps of the methods disclosed in conjunction with the embodiments of the present application may be directly embodied as being executed by a hardware processor, or executed by a combination of hardware and software modules in the processor 1302 . The software module may be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other storage media mature in the art. The storage medium is located in the memory 1304, and the processor 1302 reads the information in the memory 1304, and completes the steps of the above method in combination with its hardware.

It should be noted that the processor 1302 in this embodiment of the present application may be an integrated circuit chip, which has a signal processing capability. In the implementation process, each step of the above method embodiments may be completed by a hardware integrated logic circuit in a processor or an instruction in the form of software. The aforementioned processors may be 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 . The methods, steps, and logic block diagrams disclosed in the embodiments of this application can be implemented or executed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in conjunction with the embodiments of the present application may be directly embodied as executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other storage media mature in the art. The storage medium is located in the memory, and the processor reads the information in the memory, and completes the steps of the above method in combination with its hardware.

It can be understood that the memory 1304 in this embodiment of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically programmable Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory. Volatile memory may be random access memory (RAM), which acts as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (synchlink DRAM, SLDRAM) ) and direct memory bus random access memory (direct rambus RAM, DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but not be limited to, these and any other suitable types of memory.

When the communication device 1301 corresponds to the wireless communication device in the above method, the communication device may include a processor 1302 , a transceiver 1303 and a memory 1304 . The memory 1304 is used for storing instructions, and the processor 1302 is used for executing the instructions stored in the memory 1304, so as to realize the correlation of the wireless communication device in any one or any of the corresponding methods shown in FIG. 1 to FIG. 5a. Program.

In a possible implementation manner, the processor 1302 is configured to initiate a voice service in the first cell through the transceiver 1303, and perform the voice service in the second cell; after receiving the second message, try to access the third cell Before searching for the cell of the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell; the first cell is the cell of the 5G communication system; the second cell is the cell of the 2G communication system or the 3G communication system; The first message is sent on the second cell, and the second message is received on the second cell. The first message is used to indicate the end of the voice service; the second message is used to instruct the wireless communication device to redirect to the third cell, where the second message The message includes information of the third cell, and the third cell is a cell of the 4G communication system.

In a possible implementation manner, the wireless communication device may be the calling party or the called party. When the wireless communication device is the calling party, in a possible implementation manner, the processor 1302 is configured to transmit and receive The controller 1303 sends a session invitation message on the first cell based on the trigger of the user operation, where the session invitation message is used to initiate a voice service. In a possible implementation manner, the processor 1302 is configured to receive a paging message on the first cell through the transceiver 1303, where the paging message is used to instruct the wireless communication device to initiate a voice service. It can also be understood that the paging message is used to indicate that the wireless communication device has other wireless communication devices that initiate a voice service to it.

When the wireless communication device cannot perform the voice service on the first communication system, it can fall back to the third communication system by means of an instruction of the network device, or can fall back to the third communication system autonomously. For example, the processor 1302 is configured to receive an air interface message from the network device after the voice service is initiated in the first cell through the transceiver 1303 and before the voice service is performed in the second cell, and the air interface message is used to instruct the wireless communication device to access the second cell. community. For another example, the processor 1302 is configured to access the second cell based on a method of actively changing cells after initiating the voice service in the first cell through the transceiver 1303 and before the voice service is performed in the second cell.

In a possible implementation manner, when the wireless communication apparatus searches for a cell of the first communication system, the processor 1302 is configured to search for the first cell through the transceiver 1303 . In a possible implementation manner, the processor 1302 is configured to, through the transceiver 1303, search for historical cells of the 5G communication system when the first cell is unavailable.

In a possible implementation manner, the processor 1302 is configured to send a connection establishment request on the 5G cell through the transceiver 1303, where the connection establishment request is used to request to establish a wireless connection with the 5G cell. In this way, the processor 1302 is configured to perform services, such as data services, voice services, etc., in the 5G cell after successful access to the 5G cell through the transceiver 1303 .

In a possible implementation manner, the processor 1302 is configured to attempt to access the third cell through the transceiver 1303 after the access to the 5G cell fails.

In another possible implementation manner, the processor 1302 is configured to initiate a voice service in a first cell through the transceiver 1303, where the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the second communication system. After receiving the second message, try to access the third cell. When a radio connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

In another possible implementation manner, the processor 1302 is configured to initiate a voice service in a first cell through the transceiver 1303, where the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A third message is received on the second cell, where the third message is used to instruct the wireless communication device to redirect to the fourth cell, the third message includes information of the fourth cell, and the fourth cell is a cell of the first communication system. After receiving the third message, try to access the fourth cell. In this way, the wireless communication device can be redirected to the cell of the first communication system based on the third message, thereby improving the speed at which the wireless communication device returns to the first communication system.

For concepts related to the technical solutions provided by the embodiments of the present application involved in the communication device, for explanations, detailed descriptions, and other steps, please refer to the descriptions of the foregoing methods or other embodiments, which will not be repeated here.

According to the foregoing method, FIG. 7 is a schematic structural diagram of a communication apparatus provided by an embodiment of the present application. As shown in FIG. 7 , the communication apparatus 1401 may include a communication interface 1403 , a processor 1402 , and a memory 1404 . The communication interface 1403 is used for inputting and/or outputting information; the processor 1402 is used for executing computer programs or instructions, so that the communication device 1401 implements the method on the wireless communication device side in the above-mentioned related solutions of FIG. 1 to FIG. 5a, or enables communication The apparatus 1401 implements the method on the network device side in the above-mentioned related solutions of FIG. 1 to FIG. 5a. In this embodiment of the present application, the communication interface 1403 can implement the solution implemented by the transceiver 1303 in FIG. 6b, the processor 1402 can implement the solution implemented by the processor 1302 in FIG. 6b, and the memory 1404 can implement the memory 1304 in FIG. 6b. The implemented solution will not be repeated here.

Based on the above embodiments and the same concept, FIG. 8 is a schematic diagram of a communication apparatus provided by an embodiment of the present application. As shown in FIG. 8 , the communication apparatus 1501 may be a wireless communication apparatus or a network device, or may be a chip or a circuit, such as a Chips or circuits provided in wireless communication devices or network equipment.

The communication device may correspond to the wireless communication device in the above method. The communication apparatus may implement the steps performed by the wireless communication apparatus in any one or more of the corresponding methods shown in FIG. 1 to FIG. 5a above. The communication apparatus may include a processing unit 1502 , a communication unit 1503 and a storage unit 1504 .

The communication device 1501 is the above-mentioned wireless communication device. In a possible implementation manner, the processing unit 1502 is configured to initiate a voice service in the first cell through the communication unit 1503, and perform the voice service in the second cell; After the message, before trying to access the third cell, search for the cell of the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell; the first cell is the cell of the 5G communication system; the second cell is the 2G communication system system or a cell of a 3G communication system; a first message is sent on the second cell, and a second message is received on the second cell, the first message is used to indicate the end of the voice service; the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the 4G communication system.

In another possible implementation manner, the processing unit 1502 is configured to initiate a voice service in a first cell through the communication unit 1503, where the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the second communication system. After receiving the second message, try to access the third cell. When a radio connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

In another possible implementation manner, the processing unit 1502 is configured to initiate a voice service in a first cell through the communication unit 1503, where the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A third message is received on the second cell, where the third message is used to instruct the wireless communication device to redirect to the fourth cell, the third message includes information of the fourth cell, and the fourth cell is a cell of the first communication system. After receiving the third message, try to access the fourth cell. In this way, the wireless communication device can be redirected to the cell of the first communication system based on the third message, thereby improving the speed at which the wireless communication device returns to the first communication system.

It can be understood that, the functions of each unit in the foregoing communication apparatus 1501 may refer to the implementation of the corresponding method embodiments, and details are not described herein again.

It should be understood that the division of the units of the above communication apparatus is only a division of logical functions, and may be fully or partially integrated into a physical entity in actual implementation, or may be physically separated. In this embodiment of the present application, the communication unit 1503 may be implemented by the transceiver 1303 shown in FIG. 6b, and the processing unit 1502 may be implemented by the processor 1302 shown in FIG. 6b.

Based on the above embodiments and the same concept, FIG. 9 is a schematic diagram of a communication apparatus provided by an embodiment of the present application. As shown in FIG. 9 , the communication apparatus 1601 may be a wireless communication apparatus or a network device, or may be a chip or a circuit, such as a Chips or circuits provided in wireless communication devices or network equipment.

The communication device may correspond to the wireless communication device in the above method. The communication apparatus may implement the steps performed by the wireless communication apparatus in any one or more of the corresponding methods shown in FIG. 1 to FIG. 5a above. The communication device may include processing circuit 1602 and interface circuit 1603 .

The communication device 1601 is the above-mentioned wireless communication device. In a possible implementation manner, the processing circuit 1602 initiates a voice service in the first cell through the interface circuit 1603 and performs the voice service in the second cell; after receiving the second message , before trying to access the third cell, search for the cell of the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell; the first cell is the cell of the 5G communication system; the second cell is the cell of the 2G communication system or A cell of a 3G communication system; a first message is sent on the second cell, and a second message is received on the second cell, where the first message is used to indicate the end of the voice service; the second message is used to instruct the wireless communication device to redirect to the second cell. Three cells, wherein the second message includes information of the third cell, and the third cell is a cell of the 4G communication system.

In yet another possible implementation manner, the processing circuit 1602 is configured to initiate a voice service in the first cell through the interface circuit 1603, and the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A second message is received on the second cell, where the second message is used to instruct the wireless communication device to redirect to the third cell, wherein the second message includes information of the third cell, and the third cell is a cell of the second communication system. After receiving the second message, try to access the third cell. When a radio connection release message is received on the third cell, the cell of the first communication system is searched, and when a suitable cell of the first communication system is searched, an attempt is made to access the cell of the first communication system.

In yet another possible implementation manner, the processing circuit 1602 is configured to initiate a voice service in the first cell through the interface circuit 1603, and the first cell is a cell of the first communication system. The voice service is performed on the second cell, and the second cell is a cell of the third communication system. A first message is sent on the second cell, where the first message is used to indicate the end of the voice service. A third message is received on the second cell, where the third message is used to instruct the wireless communication device to redirect to the fourth cell, the third message includes information of the fourth cell, and the fourth cell is a cell of the first communication system. After receiving the third message, try to access the fourth cell. In this way, the wireless communication device can be redirected to the cell of the first communication system based on the third message, thereby improving the speed at which the wireless communication device returns to the first communication system.

It can be understood that, the functions of each unit in the above-mentioned communication apparatus 1601 may refer to the implementation of the corresponding method embodiments, which will not be repeated here.

It should be understood that the division of the units of the above communication apparatus is only a division of logical functions, and may be fully or partially integrated into a physical entity in actual implementation, or may be physically separated. In this embodiment of the present application, the interface circuit 1603 may be implemented by the transceiver 1303 shown in FIG. 6b, and the processing circuit 1602 may be implemented by the processor 1302 shown in FIG. 6b.

According to the method provided by the embodiment of the present application, the present application also provides a computer program product, the computer program product includes: computer program code or instructions, when the computer program code or instructions are run on a computer, the computer is made to execute FIG. 1 The method of any one of the embodiments shown in FIG. 5a.

According to the method provided by the embodiments of the present application, the present application further provides a computer-readable storage medium, where the computer-readable medium stores program codes, and when the program codes are executed on a computer, the computer executes FIG. 1 to FIG. 5 a The method of any one of the illustrated embodiments.

According to the method provided by the embodiment of the present application, the present application further provides a chip system, where the chip system may include a processor. The processor is coupled to the memory and can be used to perform the method of any of the embodiments shown in Figures 1 to 5a. Optionally, the chip system further includes a memory. Memory, used to store computer programs (also called code, or instructions). The processor is used to call and run the computer program from the memory, so that the device installed with the chip system executes the method of any one of the embodiments shown in FIG. 1 to FIG. 5a.

According to the method provided by the embodiment of the present application, the present application further provides a system, which includes the aforementioned one or more wireless communication apparatuses and one or more network devices.

In the above-mentioned embodiments, it may be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented in software, it can be implemented in whole or in part in the form of a computer program product. A computer program product includes one or more computer instructions. When computer instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable device. Computer instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server, or data center over a wire (e.g. coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (eg infrared, wireless, microwave, etc.) means to transmit to another website site, computer, server or data center. A 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, or the like that includes an integration of one or more available media. Useful media may be magnetic media (eg, floppy disk, hard disk, magnetic tape), optical media (eg, high-density digital video disc (DVD)), or semiconductor media (eg, solid state disc (SSD)) )Wait.

It should be noted that a part of this patent application file contains content protected by copyright. Except for making copies of the patent files of the Patent Office or the contents of the recorded patent files, the copyright owner reserves the right to copyright.

The network equipment in each of the foregoing apparatus embodiments corresponds to the network equipment or wireless communication apparatus in the wireless communication apparatus and method embodiments, and corresponding steps are performed by corresponding modules or units. Or the step of sending, other steps except sending and receiving may be performed by a processing unit (processor). For functions of specific units, reference may be made to corresponding method embodiments. The number of processors may be one or more.

The terms "component", "module", "system" and the like are used in this specification to refer to a computer-related entity, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device may be components. One or more components may reside within a process and/or thread of execution, and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. A component may, for example, be based on a signal having one or more data packets (eg, data from two components interacting with another component between a local system, a distributed system, and/or a network, such as the Internet interacting with other systems via signals) Communicate through local and/or remote processes.

Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in connection with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware accomplish. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described systems, devices and units may refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, for example, multiple units or components may be combined or integrated. to another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.

Units described as separate components may or may not be physically separated, and components shown as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution, and the computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program codes .

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, and should cover within the scope of protection of this application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

A method for a wireless communication device, comprising:

Initiating a voice service in a first cell, where the first cell is a cell of a 5G communication system;

performing the voice service on a second cell, where the second cell is a cell of a 2G communication system or a 3G communication system;

sending a first message on the second cell, where the first message is used to indicate the end of the voice service;

A second message is received on the second cell, the second message is used to instruct the wireless communication device to redirect to a third cell, wherein the second message includes information of the third cell, so The third cell is a cell of the 4G communication system;

After receiving the second message, before attempting to access the third cell, search for a cell in the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell.
The method of claim 1, wherein:

The initiating voice service in the first cell includes:

Based on a trigger of a user operation, a session invitation message is sent on the first cell, where the session invitation message is used to initiate the voice service.
The method of claim 1, wherein:

The initiating voice service in the first cell includes:

A paging message is received on the first cell, the paging message instructing the wireless communication device to initiate the voice service.
The method according to any one of claims 1 to 3, wherein:

After the first cell initiates the voice service and before the second cell performs the voice service, the method further includes:

An air interface message from a network device is received, where the air interface message is used to instruct the wireless communication apparatus to access the second cell.
The method according to any one of claims 1 to 3, wherein:

After the first cell initiates the voice service and before the second cell performs the voice service, the method further includes:

The second cell is accessed based on the way of actively changing the cell.
The method according to any one of claims 1 to 5, wherein:

The searching for a cell of the 5G communication system includes: searching for the first cell.
The method of claim 6, wherein:

The searching for a cell of the 5G communication system further includes:

When the first cell is unavailable, a historical cell of the 5G communication system is searched.
The method according to any one of claims 1 to 7, wherein:

The attempt to access the 5G cell includes:

A connection establishment request is sent on the 5G cell, where the connection establishment request is used to request the establishment of a wireless connection with the 5G cell.
The method of any one of claims 1 to 8, further comprising:

After the access to the 5G cell is successful, the data service is performed in the 5G cell.
The method of any one of claims 1 to 9, further comprising:

After the access to the 5G cell fails, try to access the third cell.
The method according to any one of claims 1 to 10, wherein:

The first message is a call hang-up message, and the second message is a connection release message.
A wireless communication device, comprising:

A processing circuit, and an interface circuit coupled to the processing circuit, wherein the processing circuit is configured to, via the interface circuit:

Initiating a voice service in a first cell, where the first cell is a cell of a 5G communication system;

performing the voice service on a second cell, where the second cell is a cell of a 2G communication system or a 3G communication system;

sending a first message on the second cell, where the first message is used to indicate the end of the voice service;

A second message is received on the second cell, the second message is used to instruct the wireless communication device to redirect to a third cell, wherein the second message includes information of the third cell, so The third cell is a cell of the 4G communication system;

After receiving the second message, before attempting to access the third cell, search for a cell in the 5G communication system, and when a suitable 5G cell is found, try to access the 5G cell.
The wireless communication device according to claim 12, wherein the processing circuit is configured to pass the interface circuit, and is specifically configured to:

Based on a trigger of a user operation, a session invitation message is sent on the first cell, where the session invitation message is used to initiate the voice service.
The wireless communication device according to claim 12, wherein the processing circuit is configured to pass the interface circuit, and is specifically configured to:

A paging message is received on the first cell, the paging message instructing the wireless communication device to initiate the voice service.
The wireless communication device according to any one of claims 12 to 14, wherein the processing circuit is configured to pass through the interface circuit and further:

After the first cell initiates the voice service and before the second cell performs the voice service, an air interface message is received from the network device, and the air interface message is used to instruct the wireless communication device to access the wireless communication device. the second district.
The wireless communication device according to any one of claims 12 to 14, wherein the processing circuit is configured to pass through the interface circuit and further:

After the first cell initiates the voice service, and before the second cell performs the voice service, the second cell is accessed based on a method of actively changing cells.
The wireless communication device according to any one of claims 12 to 16, wherein the processing circuit is configured to pass the interface circuit, and is specifically configured to:

The first cell is searched.
The wireless communication device of claim 17, wherein the processing circuit is configured to pass through the interface circuit and further:

When the first cell is unavailable, a historical cell of the 5G communication system is searched.
The wireless communication device according to any one of claims 12 to 18, wherein the processing circuit is configured to pass the interface circuit, and is specifically configured to:

A connection establishment request is sent on the 5G cell, where the connection establishment request is used to request the establishment of a wireless connection with the 5G cell.
The wireless communication device according to any one of claims 12 to 19, wherein the processing circuit is configured to pass the interface circuit, and further:

After the access to the 5G cell is successful, the data service is performed in the 5G cell.
The wireless communication device according to any one of claims 12 to 20, wherein the processing circuit is configured to pass the interface circuit and further:

After the access to the 5G cell fails, try to access the third cell.
The wireless communication device according to any one of claims 12 to 21, wherein,

The first message is a call hang-up message, and the second message is a connection release message.
A communication device, characterized in that the device comprises a processor and a memory,

the memory for storing executable programs;

The processor is adapted to execute a computer-executable program in the memory, so that the method of any one of claims 1-11 is performed.
A communication device, characterized in that the device comprises a processor and a communication interface,

the communication interface for inputting and/or outputting information;

The processor is configured to execute a computer-executable program such that the method of any one of claims 1-11 is performed.
A computer-readable storage medium, characterized in that, the computer-readable storage medium stores a computer-executable program, and when the computer-executable program is invoked by a computer, the computer executes any one of claims 1 to 11. one of the methods described.
A chip system, characterized in that it includes:

the communication interface for inputting and/or outputting information;

The processor is used for executing the computer executable program, so that the device installed with the chip system executes the method according to any one of claims 1-11.