Communication method, device and computer readable storage medium

Abstract

The embodiments of the present application provide a communication method, device and computer-readable storage medium, which relate to the field of communication technology. The method includes: a terminal device falls back from a first communication network to a second communication network to initiate a voice call, and when the voice call ends and the redirection to the first cell fails, a registration request is sent to the second communication network; wherein the network standards of the first communication network and the second communication network are different, and the first cell is a cell under the first communication network. The embodiments of the present application can prevent the terminal device from being unable to receive paging, which helps to improve the call connection rate of the terminal device.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method, device and computer-readable storage medium. Background Art

[0002] Currently, some communication networks cannot directly carry out voice call services, such as the 5th generation mobile communication technology (5G) network.

[0003] When a terminal device initiates a call on a 5G network, the terminal device can use a fallback mechanism, such as the evolved packet system fall back (EPSFB) mechanism, to fall back to a communication network that can carry out voice call services, such as falling back to the 4th generation mobile communication technology (4G) network, and then use the 4G network to make a voice call. Usually, after the voice call ends, the terminal device will first release its radio resource control (RRC) connection with the 4G network, and then access the 5G network through redirection.

[0004] However, if the redirection fails, the terminal device will not be able to receive the page. Summary of the invention

[0005] The embodiments of the present application provide a communication method, a device, and a computer-readable storage medium, which are applied to the field of communication technology and can prevent a terminal device from being unable to receive a paging call.

[0006] In a first aspect, an embodiment of the present application provides a communication method, the method comprising:

[0007] Initiate a voice call from a first communication network to a second communication network, where the first communication network and the second communication network have different network standards;

[0008] When the voice call ends and redirection to the first cell fails, a registration request is sent to the second communication network; the first cell is a cell under the first communication network.

[0009] In a possible embodiment, sending a registration request to the second communication network includes:

[0010] A location update request is sent to a core network element of the second communication network, where the location update request is used to request the core network element to update location information of the terminal device.

[0011] In a possible embodiment, the location update request includes a tracking area update (TAU) request, and the TAU request includes the location information of the terminal device.

[0012] In a possible embodiment, the location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0013] In a possible embodiment, the TAU request includes a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0014] In a possible embodiment, when the value of the first field is a first value, the first field is used to trigger the core network element and the network device to synchronize the location information of the terminal device; the network device belongs to the second communication network.

[0015] In a possible embodiment, the method further includes:

[0016] When successfully registered with the second communication network, paging from the core network element is received.

[0017] In a second aspect, an embodiment of the present application provides a communication method, the method comprising:

[0018] Receiving a registration request for a second communication network sent from a terminal device when a voice call ends and redirection to a first cell fails; the voice call is a voice call initiated by the terminal device from the first communication network to the second communication network, the first cell is a cell under the first communication network, and the network standards of the first communication network and the second communication network are different;

[0019] Update the registration information of the terminal device.

[0020] In a possible embodiment, the registration request includes a location update request; and updating the registration information of the terminal device includes:

[0021] The location information of the terminal device is updated based on the location update request.

[0022] In a possible embodiment, the location update request includes a TAU request, and the TAU request includes the location information of the terminal device.

[0023] In a possible embodiment, the location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0024] In a possible embodiment, the TAU request includes a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0025] In a possible embodiment, the method further includes:

[0026] When the value of the first field is the first value, the location information of the terminal device is synchronized with a network device; the network device belongs to the second communication network.

[0027] In a possible embodiment, the method further includes:

[0028] In the case that there is a voice call request initiated to the terminal device, paging is initiated to the terminal device.

[0029] In a third aspect, an embodiment of the present application provides a terminal device, including: a processor and a memory;

[0030] The memory stores computer-executable instructions;

[0031] The processor executes the computer-executable instructions stored in the memory, so that the terminal device executes the communication method provided in the first aspect.

[0032] In a fourth aspect, an embodiment of the present application provides a core network device, including: a processor and a memory;

[0033] The memory stores computer-executable instructions;

[0034] The processor executes the computer execution instructions stored in the memory, so that the core network device executes the communication method provided in the second aspect.

[0035] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the communication method provided in the first aspect is implemented; or the communication method provided in the second aspect is implemented.

[0036] In a sixth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed, enables a computer to execute the communication method provided in the first aspect; or execute the communication method provided in the second aspect.

[0037] In the seventh aspect, the present application provides a chip or a chip system, which includes at least one processor and a communication interface, the communication interface and the at least one processor are interconnected through a line, and the at least one processor is used to run a computer program or instruction to execute the method described in the first aspect or any possible embodiment of the first aspect; or, the at least one processor is used to run a computer program or instruction to execute the method described in the second aspect or any possible embodiment of the second aspect. Among them, the communication interface in the chip can be an input / output interface, a pin or a circuit, etc.

[0038] In a possible implementation, the chip or chip system described above further includes at least one memory, in which instructions are stored. The memory may be a storage unit inside the chip, such as a register, a cache, etc., or a storage unit of the chip (such as a read-only memory, a random access memory, etc.).

[0039] In the communication method, device, and computer-readable storage medium provided by the embodiments of the present application, the terminal device falls back from the first communication network to the second communication network to initiate a voice call, and when the voice call ends and the redirection to the first cell fails, the terminal device sends a registration request to the second communication network. In the above scheme, when the terminal device fails to redirect to the first cell, by re-sending the registration request to the second communication network, the terminal device can be prevented from failing to receive paging, which helps to improve the call connection rate of the terminal device. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of a communication system architecture provided in an embodiment of the present application;

[0041] Figure 2 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 1 ;

[0042] Figure 3 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 2 ;

[0043] Figure 4 A schematic diagram of a communication method provided in an embodiment of the present application;

[0044] Figure 5 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 3 ;

[0045] Figure 6 A schematic diagram of the steps of another communication method provided in an embodiment of the present application;

[0046] Figure 7 A schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0048] In the embodiments of the present application, words such as "first" and "second" are used to distinguish between identical or similar items with substantially identical functions and effects. For example, the first indication information and the second indication information are only used to distinguish between different indication information, and do not limit their order. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0049] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, a--c, bc, or abc, where a, b, and c can be single or multiple.

[0050] In order to clearly describe the technical solutions of the embodiments of the present application, some of the terms and technologies involved in the embodiments of the present application are briefly introduced below:

[0051] 1. TAU request: Tracking area update request. When a terminal device moves from one tracking area (TA) to another, it must re-register its location in the new TA to notify the network to change the location information of the terminal device it stores. TAU helps the network understand the current location of the terminal device so that it can provide services and process communication requests more accurately.

[0052] 2. S criterion: A basic condition for evaluating whether a terminal device should stay in the current cell. It is based on the measurement and evaluation results of the cell's wireless signal by the terminal device. Only when the quality of the wireless signal provided by the cell meets the requirements of the S criterion, the terminal device may select the cell as the resident cell. The terminal device will measure the cell regularly and evaluate whether the S criterion is met based on the measurement results. If it is met, the terminal device may select the cell as the current resident cell; if it is not met, the terminal device may try to search for other cells that meet the S criterion and perform cell selection and reselection.

[0053] 3. EPSFB mechanism: Evolved Packet System Fallback Mechanism, refers to the mechanism in which, when the 5G network does not have the voice over new radio (VoNR) function, the voice service falls back from the 5G network to the 4G network, relying on the voice over long-term evolution (VoLTE) function to ensure the continuity of the voice service.

[0054] 4. Redirection: It is a guidance mechanism for terminal devices on the network side, which is used to guide terminal devices to switch from one radio access technology (RAT) or cell to another RAT or cell. Redirection usually occurs when a terminal device attempts to access the network or communicate. Due to some reasons (such as congestion in the current cell, unsupported frequency band, etc.), the current serving cell or network cannot provide satisfactory service to the terminal device. At this time, the network side will send a redirection instruction to the terminal device to guide the terminal device to switch to another more suitable cell or network.

[0055] 5. Core network element: According to the protocol, it is the network element that performs core switching or call routing functions. The functions of the core network element are mainly to provide user connection, user management and service bearing, and to provide an interface to the external network as a bearer network. The establishment of user connection includes mobility management, call management, switching / routing, recording notification (combined with intelligent network services to complete the connection relationship with intelligent network peripheral devices) and other functions.

[0056] 6. Terminal equipment:

[0057] The terminal device of the embodiment of the present application may include a handheld device, a vehicle-mounted device, etc. with a wireless communication function. For example, some terminal devices include: mobile phones, tablet computers, PDAs, laptop computers, mobile internet devices (MID), wearable devices, VR devices, AR devices, wireless terminals in industrial control, wireless terminals in self driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication functions, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, terminal devices in 5G networks, or terminal devices in future evolved public land mobile communication networks (PLMNs), etc., and the embodiments of the present application are not limited to this.

[0058] As an example but not limitation, in the embodiments of the present application, the terminal device may also be a wearable device. Wearable devices may also be referred to as wearable smart devices, which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not only hardware devices, but also powerful functions achieved through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include full-featured, large-sized, and fully or partially independent of smartphones, such as smart watches or smart glasses, as well as devices that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various types of smart bracelets and smart jewelry for vital sign monitoring.

[0059] In addition, in the embodiments of the present application, the terminal device may also be a terminal device in an Internet of Things (IoT) system. IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, thereby realizing an intelligent network that interconnects people and machines and things.

[0060] The terminal device in the embodiments of the present application may also be referred to as: user equipment (UE), mobile station (MS), mobile terminal (MT), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication equipment, user agent or user device, etc.

[0061] In an embodiment of the present application, the electronic device or each network device includes a hardware layer, an operating system layer running on the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and a memory (also called main memory). The operating system can be any one or more computer operating systems that implement business processing through processes, such as a Linux operating system, a Unix operating system, an Android operating system, an iOS operating system, or a Windows operating system. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software.

[0062] In an embodiment of the present application, the device for implementing the function of the terminal device may be the terminal device itself; or it may be a device that can support the terminal device to implement the function, such as a chip system, which may be installed in the terminal device.

[0063] 7. Network equipment

[0064] The network device in the embodiments of the present application may refer to a public mobile communication network device, which is an interface device for a terminal device to access the Internet. It is also a form of a radio station, which refers to a radio transceiver station for transmitting information with a terminal device within a certain radio coverage area, including a base station (BS), which may also be referred to as a base station device, and is a device deployed in a radio access network (RAN) to provide wireless communication functions. For example, the equipment that provides base station functions in 2G networks includes base transceiver stations (BTS), the equipment that provides base station functions in 3G networks includes NodeB, the equipment that provides base station functions in 4G networks includes evolved nodeB (eNB), in wireless local area networks (WLAN), the equipment that provides base station functions is access point (AP), the equipment that provides base station functions in 5G NR is gNB, and the evolving nodeB (ng-eNB), wherein the gNB and the terminal equipment communicate using NR technology, the ng-eNB and the terminal equipment communicate using evolved universal terrestrial radio access (E-UTRA) technology, and both gNB and ng-eNB can be connected to the 5G core network. The network device 103 in the embodiment of the present application also includes equipment that provides base station functions in future new communication systems, etc.

[0065] In an embodiment of the present application, the device for implementing the function of the network device may be the network device itself, or may be a device that can support the network device to implement the function, such as a chip system, which may be installed in the network device.

[0066] In order to better understand the method provided in the embodiments of the present application, the communication system architecture that may be involved in the embodiments of the present application is first described below.

[0067] For example, refer to Figure 1 , Figure 1 Schematic diagram of a communication system architecture provided in an embodiment of the present application. Figure 1 As shown, the communication system 100 includes a terminal device 101 , a network device 102 and a network device 103 , and the terminal device 101 can communicate wirelessly with one of the network device 102 and the network device 103 .

[0068] In some implementations, network device 102 and network device 103 belong to communication networks of different network formats. For example, when network device 102 belongs to a 5G network, network device 103 may belong to a 4G network. Alternatively, when network device 102 belongs to a 4G network, network device 103 may belong to a 3G network or a 2G network, which is not limited in the embodiments of the present application.

[0069] In the embodiment of the present application, the wireless communication between the terminal device 101 and the network device 102 or the network device 103 may also be referred to as "communication", and the term "communication" may also be described as "data transmission", "information transmission" or "transmission". Those skilled in the art may use the technical solution provided in the embodiment of the present application for wireless communication between network devices and terminal devices, such as wireless communication between access network devices and terminal devices, and wireless communication between core network devices and terminal devices.

[0070] At present, some communication networks cannot directly carry out voice call services, such as 5G independent networking. For networks that cannot carry out voice calls, terminal devices can use a fallback mechanism, such as the EPSFB mechanism, to fall back to a network that can carry out voice calls, for example, from a 5G independent networking to a 4G network, and then use VoLTE technology in the 4G network to carry out voice calls.

[0071] The following example uses a terminal device falling back from a 5G independent network to a 4G network, and then using VoLTE technology to make a voice call in the 4G network:

[0072] Usually, after the voice call of the terminal device ends, the 4G network will first release its RRC connection with the terminal device, and then the terminal device will access the 5G network through redirection.

[0073] In some implementations, the network device releases its RRC connection with the terminal device through an RRC Release message, and carries the information of the target cell under the 5G network in the RRC Release message. The terminal device needs to re-initiate the RRC connection based on the information of the target cell to access the 5G network. However, if the target cell does not meet the S criterion, the terminal device will not be able to access the 5G network. In this case, the terminal device will still stay in the 4G network, and subsequent voice calls will also be initiated by the core network element of the 4G network using the 4G network to paging the terminal device.

[0074] For example, refer to Figure 2 , Figure 2 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 1 .

[0075] exist Figure 2In one embodiment shown, the terminal device may send a registration request to the 5G network in advance. After successfully registering with the 5G network, if the terminal device needs to initiate a voice call in the 5G network, due to some reasons (such as insufficient coverage, etc.), the terminal device may fall back to the 4G network for the voice call. Specifically, the following steps may be performed:

[0076] 1. Falling back to the 4G network: The terminal device will register to the 4G network based on the Evolved Packet System fallback mechanism. This usually involves reselecting and accessing a 4G base station.

[0077] 2. VoLTE calls: Once the network successfully falls back to the 4G network, the terminal device can use VoLTE technology to make voice calls.

[0078] 3. Core network element processing: During the fallback process, the core network element will perform necessary processing to ensure the continuity of the call, which may include session transfer, resource allocation, and signaling interaction.

[0079] In some embodiments, after the voice call of the terminal device ends, the 4G network will first release the RRC connection between it and the terminal device, for example, by releasing the RRC connection between it and the terminal device through an RRC Release message, and at the same time carrying the information of the target NR cell under the 5G network in the RRC Release message.

[0080] If the target NR cell does not meet the S criterion, the terminal device will not be able to access the 5G network. In this case, the terminal device will still remain in the 4G network, and subsequent voice calls will also be initiated by the core network element of the 4G network using the 4G network to paging the above terminal device.

[0081] It is understandable that when the core network element needs to contact the terminal device (for example, there is an incoming call), the mobility management entity (MME) will send a paging request to the corresponding base station based on the last registered location information of the terminal device. After receiving the paging request, the base station will broadcast the paging message within its coverage area. These messages contain the identification information of the terminal device and other necessary control information. After receiving the paging message, the terminal device will parse the message content and take appropriate actions as needed (for example, establish a communication connection to receive an incoming call).

[0082] However, in the above implementation, there may be incompatibility between the core network elements of the 4G network and the core network elements of the 5G network, and between the 4G base station and the 5G base station. In this case, after the voice call of the terminal device ends and the 4G network releases the RRC connection between the terminal device, the 4G network may default to the terminal device successfully accessing the 5G network through redirection. As a result, the core network elements of the 4G network will no longer maintain the location information of the terminal device, and will no longer use the 4G network to initiate paging to the above-mentioned terminal device, resulting in the terminal device being unable to receive the paging.

[0083] For example, refer to Figure 3 , Figure 3 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 2 .

[0084] exist Figure 3 In one implementation shown, the terminal device can send a registration request to the 5G network in advance. After successfully registering with the 5G network, if the terminal device needs to initiate a voice call in the 5G network, due to certain reasons (such as insufficient coverage, etc.), the terminal device can fall back to the 4G network for the voice call.

[0085] After the voice call of the terminal device ends, the 4G network will first release its RRC connection with the terminal device, for example, through an RRC Release message, and carry the information of the target NR cell under the 5G network in the RRC Release message. If the target NR cell does not meet the S criterion, the terminal device will not be able to access the 5G network. In this case, the terminal device will still stay in the 4G network, but due to abnormal conditions (such as compatibility issues between devices), the core network element of the 4G network will no longer use the 4G network to initiate paging to the above-mentioned terminal device, resulting in the terminal device being unable to receive paging.

[0086] In summary, how to prevent the terminal device from failing to receive paging is a problem that needs to be solved urgently. In this regard, the embodiment of the present application proposes a communication method, in which when the terminal device falls back from the first communication network to the second communication network to initiate a voice call, when the voice call ends and the redirection to the first cell fails, the terminal device resends a registration request to the second communication network, thereby preventing the terminal device from failing to receive paging and improving the call connection rate of the terminal device.

[0087] The technical solution provided by the present application is described in detail below through specific embodiments. It should be noted that the following embodiments can exist independently or in combination with each other, and the same or similar contents will not be described repeatedly in different embodiments.

[0088] Reference Figure 4 , Figure 4 This is a schematic diagram of a step flow of a communication method provided in an embodiment of the present application. In some embodiments of the present application, the communication method includes:

[0089] S401. The terminal device falls back from the first communication network to the second communication network to initiate a voice call.

[0090] Optionally, the network standards of the first communication network and the second communication network are different, that is, the first communication network and the second communication network use different wireless access technologies. For example, when the first communication network is a 5G network based on NR technology, the second communication network can be a 4G network based on LTE technology; when the first communication network is a 4G network, the second communication network can be a 3G network or a 2G network, which is not limited in the embodiments of the present application.

[0091] In some implementations, when initiating a voice call, the terminal device will decide whether to fall back from the first communication network to the second communication network based on the current network environment and conditions.

[0092] When deciding to fall back, the terminal device will search for available base stations in the second communication network and select a suitable base station for access. After the terminal device accesses the base station of the second communication network, it needs to go through the registration and authentication process. This includes sending a registration request to the core network element of the second communication network, providing the device identification and authentication information so that the core network element can identify and authorize the device to access.

[0093] When the registration and authentication are successful, the terminal device can establish a voice call on the second communication network.

[0094] S402. When the voice call ends and redirection to the first cell fails, the terminal device sends a registration request to the second communication network; the above-mentioned first cell is a cell under the first communication network.

[0095] In some implementations, after the voice call ends, if the terminal device fails in its attempt to redirect back to the first cell of the first communication network, the terminal device may resend a registration request to the second communication network to maintain the connection in the second communication network.

[0096] In some implementations, if the terminal device re-registers with the second communication network, a subsequent voice call can be initiated by a core network element of the second communication network using the second communication network to initiate paging to the terminal device.

[0097] In the communication method provided in the embodiment of the present application, when the terminal device falls back from the first communication network to the second communication network to initiate a voice call, when the voice call ends and redirection to the first cell fails, the terminal device resends a registration request to the second communication network, thereby preventing the terminal device from being unable to receive paging and improving the call connection rate of the terminal device.

[0098] Based on the contents described in the above embodiments, in some embodiments of the present application, when the terminal device falls back from the first communication network to the second communication network to initiate a voice call, when the voice call ends and redirection to the first cell fails, a location update request can be sent to the core network element of the second communication network. The location update request is used to request the above-mentioned core network element to update the location information of the terminal device.

[0099] It is understandable that after the core network element updates the location information of the terminal device, if the core network element needs to contact the terminal device (for example, there is an incoming call), the MME can send a paging request to the corresponding base station based on the updated location information of the terminal device. After the base station receives the paging request, it can broadcast the paging message within its coverage area. This can prevent the terminal device from being unable to receive the paging and improve the call connection rate of the terminal device.

[0100] Optionally, in some implementations, the location update request may include a TAU request, which includes location information of the terminal device.

[0101] Optionally, the above-mentioned location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0102] In some embodiments, when the terminal device falls back from the first communication network to the second communication network to initiate a voice call, when the voice call ends and redirection to the first cell fails, the terminal device can send a TAU request to the second communication network to inform the second communication network of its current tracking area.

[0103] Specifically, the terminal device initiates a TAU request and can send its location information to the core network element of the second communication network through the base station where it is located. The core network can update the location information of the terminal device and determine the base station to which the terminal device is currently connected by processing the TAU request.

[0104] In some embodiments, the TAU request may include a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0105] Optionally, the first field may be a newly added field or an expandable field in the TAU request.

[0106] Exemplarily, the first field may be a newly added "redirection synchronization failure field" in the TAU request, which is used for the terminal device to inform the network side of the redirection failure and then perform a network internal registration update.

[0107] Optionally, the length of the first field may be 1 byte.

[0108] In some implementations, when the value of the first field is the first value, the first field is used to trigger the core network element to synchronize the location information of the terminal device with the network device of the second communication network.

[0109] Optionally, the first value may be 1 or 0.

[0110] For example, refer to Figure 5 , Figure 5 A schematic diagram of the operation of a voice call service provided in an embodiment of the present application Figure 3 .

[0111] exist Figure 5 In one embodiment shown, the terminal device can send a registration request to the first communication network in advance. After successfully registering with the first communication network, if the terminal device needs to initiate a voice call in the first communication network, due to certain reasons (such as insufficient coverage, etc.), the terminal device can fall back to the second communication network for the voice call.

[0112] After the voice call of the terminal device ends, the second communication network will first release its RRC connection with the terminal device, for example, by releasing the RRC connection with the terminal device through an RRC Release message, and at the same time carrying the information of the target cell of the first communication network in the RRC Release message. If the target cell does not meet the S criterion, the terminal device will not be able to access the first communication network. In this case, the terminal device can initiate a TAU request carrying the first field and re-register with the second communication network, so that the network side can synchronize and update the core network elements and base stations of the second communication network.

[0113] In some implementations, after the terminal device re-registers with the second communication network, it continues to stay in the second communication network and can receive paging from the core network element of the second communication network. That is, after the terminal device re-registers with the second communication network, subsequent voice calls will be initiated by the core network element of the second communication network to the terminal device using the second communication network.

[0114] In some embodiments of the present application, a communication method is also provided, which can be applied to a core network element of a second communication network. Figure 6 , Figure 6This is a schematic diagram of the steps of another communication method provided in an embodiment of the present application. In some embodiments of the present application, the communication method includes:

[0115] S601. Receive a registration request for a second communication network sent from a terminal device when a voice call ends and redirection to a first cell fails; the above-mentioned voice call is a voice call initiated by the terminal device from the first communication network to the second communication network, and the above-mentioned first cell is a cell under the first communication network.

[0116] In some implementations, the network standards of the first communication network and the second communication network are different. For example, when the first communication network is a 5G network based on NR technology, the second communication network may be a 4G network based on LTE technology; when the first communication network is a 4G network, the second communication network may be a 3G network or a 2G network, which is not limited in the embodiments of the present application.

[0117] In some embodiments, when a terminal device initiates a voice call on a first communication network, if the first communication network cannot directly provide voice call services, the terminal device can use a fallback mechanism to fall back to a second communication network that can provide voice call services, and then use the second communication network to make a voice call.

[0118] After the voice call ends, if the terminal device fails in its attempt to redirect back to the first cell of the first communication network, the terminal device can resend a registration request to the core network element of the second communication network to maintain the connection in the second communication network.

[0119] S602: Update the registration information of the terminal device.

[0120] In some implementations, when the terminal device re-registers with the second communication network, the core network element of the second communication network may update the registration information of the terminal device, thereby enabling the core network element to timely grasp the location information of the terminal device.

[0121] In some implementations, after the core network element updates the registration information of the terminal device, if the core network element needs to contact the terminal device (for example, there is an incoming call), the MME can send a paging request to the corresponding base station based on the updated location information of the terminal device. After the base station receives the paging request, it can broadcast the paging message within its coverage area. This can prevent the terminal device from being unable to receive the paging and improve the call connection rate of the terminal device.

[0122] Based on the contents described in the above embodiments, in some embodiments of the present application, the above registration request includes a location update request; after receiving the above location update request, the above core network element can update the location information of the terminal device based on the location update request.

[0123] Optionally, in some implementations, the location update request may include a TAU request, which includes location information of the terminal device.

[0124] Optionally, the above-mentioned location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0125] In some embodiments, when the terminal device falls back from the first communication network to the second communication network to initiate a voice call, when the voice call ends and redirection to the first cell fails, the terminal device can send a TAU request to the core network element of the second communication network to inform the core network element of the second communication network of the tracking area where it is currently located.

[0126] Specifically, the terminal device initiates a TAU request and can send its location information to the core network element of the second communication network through the base station where it is located. The core network can update the location information of the terminal device by processing the TAU request.

[0127] In some embodiments, the TAU request may include a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0128] Optionally, the first field may be a newly added field or an expandable field in the TAU request.

[0129] Exemplarily, the first field may be a newly added "redirection synchronization failure field" in the TAU request, which is used for the terminal device to inform the network side of the redirection failure and then perform a network internal registration update.

[0130] Optionally, the length of the first field may be 1 byte.

[0131] In some implementations, when the core network element of the second communication network receives the TAU request, if the value of the first field is the first value, it can synchronize the location information of the terminal device with the network device of the second communication network.

[0132] Optionally, the first value may be 1 or 0.

[0133] In some implementations, after the terminal device re-registers with the second communication network, it continues to stay in the second communication network. If the core network element of the second communication network needs to contact the terminal device (such as a voice call request initiated to the terminal device), the MME can send a paging request to the corresponding base station based on the updated location information of the terminal device. After receiving the paging request, the base station can broadcast the paging message within its coverage area. This can prevent the terminal device from being unable to receive the paging and improve the call connection rate of the terminal device.

[0134] The method of the embodiment of the present application has been described above, and the device for executing the above method provided by the embodiment of the present application is described below. Those skilled in the art can understand that the method and the device can be combined and referenced with each other, and the relevant device provided by the embodiment of the present application can execute the steps in the above method.

[0135] In some embodiments, an embodiment of the present application provides a communication device, which can be applied to a terminal device, and the communication device includes:

[0136] A voice call module, used to initiate a voice call from a first communication network to a second communication network, where the first communication network and the second communication network have different network standards;

[0137] A registration module is used to send a registration request to the second communication network when the voice call ends and redirection to the first cell fails; the first cell is a cell under the first communication network.

[0138] In a possible implementation, the registration module is used to:

[0139] A location update request is sent to a core network element of the second communication network, where the location update request is used to request the core network element to update location information of the terminal device.

[0140] In a possible implementation, the location update request includes a TAU request, and the TAU request includes the location information of the terminal device.

[0141] In a possible implementation manner, the location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0142] In a possible implementation, the TAU request includes a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0143] In a possible implementation, when the value of the first field is a first value, the first field is used to trigger the core network element and the network device to synchronize the location information of the terminal device; the network device belongs to the second communication network.

[0144] In a possible implementation manner, the communication device further includes a receiving module, configured to:

[0145] When successfully registered with the second communication network, paging from the core network element is received.

[0146] In some embodiments, an embodiment of the present application further provides a communication device, which can be applied to a core network element, and the communication device includes:

[0147] A receiving module, configured to receive a registration request for a second communication network sent from a terminal device when a voice call ends and redirection to a first cell fails; the voice call is a voice call initiated by the terminal device from the first communication network falling back to the second communication network, the first cell is a cell under the first communication network, and the network standards of the first communication network and the second communication network are different;

[0148] An updating module is used to update the registration information of the terminal device.

[0149] In a possible implementation manner, the registration request includes a location update request; and the updating module is used to:

[0150] The location information of the terminal device is updated based on the location update request.

[0151] In a possible implementation, the location update request includes a TAU request, and the TAU request includes the location information of the terminal device.

[0152] In a possible implementation manner, the location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

[0153] In a possible implementation, the TAU request includes a first field, where the first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

[0154] In a possible implementation manner, the update module is used to:

[0155] When the value of the first field is the first value, the location information of the terminal device is synchronized with a network device; the network device belongs to the second communication network.

[0156] In a possible implementation manner, the communication device further includes a paging module, configured to:

[0157] In the case that there is a voice call request initiated to the terminal device, paging is initiated to the terminal device.

[0158] It should be noted that the module names involved in the embodiments of the present application can be defined as other names as long as the functions of each module can be achieved, and there is no specific restriction on the names of the modules.

[0159] The method provided in the embodiment of the present application can be applied to electronic devices with communication functions. The electronic devices include terminal devices or core network devices. The specific device forms of the terminal devices or core network devices can refer to the above related descriptions and will not be repeated here.

[0160] Reference Figure 7 , Figure 7 The hardware structure diagram of an electronic device provided in an embodiment of the present application is shown in FIG. The electronic device 70 provided in an embodiment of the present application includes: a processor 701 and a memory 702; the memory 702 stores computer-executable instructions; the processor 701 executes the computer-executable instructions stored in the memory 702, so that the electronic device performs the above method.

[0161] The embodiment of the present application provides a chip, which includes a processor, and the processor is used to call a computer program in a memory to execute the technical solution in the above embodiment. Its implementation principle and technical effect are similar to those of the above related embodiments, and will not be repeated here.

[0162] The embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium stores a computer program. The above method is implemented when the computer program is executed by the processor. The method described in the above embodiment can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. If implemented in software, the function can be stored as one or more instructions or codes on a computer-readable medium or transmitted on a computer-readable medium. Computer-readable media can include computer storage media and communication media, and can also include any medium that can transfer a computer program from one place to another. The storage medium can be any target medium that can be accessed by a computer.

[0163] In one possible implementation, computer readable media may include RAM, ROM, compact disc read-only memory (CD-ROM) or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that is intended to carry or store the required program code in the form of instructions or data structures and can be accessed by the computer. Moreover, any connection is appropriately referred to as a computer readable medium. For example, if the software is transmitted from a website, server or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology (such as infrared, radio and microwave), the coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of medium. Disks and optical disks as used herein include optical disks, laser disks, optical disks, digital versatile discs (DVD), floppy disks and Blu-ray discs, where disks usually reproduce data magnetically, while optical disks reproduce data using laser optical principles. Combinations of the above should also be included in the scope of computer readable media.

[0164] An embodiment of the present application also provides a computer program product, which includes a computer program. When the computer program is executed, the computer executes the above method.

[0165] The above specific implementation methods further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the present invention should be included in the scope of protection of the present invention.

Claims

1. A communication method, characterized in that: The method comprises: Initiate a voice call from a first communication network to a second communication network, where the first communication network and the second communication network have different network standards; When the voice call ends and redirection to the first cell fails, sending a location update request to a core network element of the second communication network, wherein the location update request is used to request the core network element to update the location information of the terminal device; the first cell is a cell under the first communication network; The location update request includes a TAU request, and the TAU request includes the location information of the terminal device; the TAU request includes a first field; when the value of the first field is a first value, the first field is used to trigger the core network element to synchronize the location information of the terminal device with the network device; the network device belongs to the second communication network; After the terminal device falls back from the first communication network to the second communication network and before initiating a voice call, the terminal device has successfully registered with the second communication network.

2. The method according to claim 1, characterized in that The location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

3. The method according to claim 1, characterized in that The first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

4. The method according to claim 1, characterized in that The method further comprises: When successfully registered with the second communication network, paging from the core network element is received.

5. A communication method, characterized in that: The method comprises: Receiving a registration request for a second communication network sent from a terminal device when a voice call ends and redirection to a first cell fails; the registration request includes a location update request; the voice call is a voice call initiated by the terminal device falling back from the first communication network to the second communication network, the first cell is a cell under the first communication network, and the network standards of the first communication network and the second communication network are different; updating the location information of the terminal device based on the location update request; the location update request includes a TAU request, the TAU request includes the location information of the terminal device; the TAU request includes a first field; When the value of the first field is a first value, synchronizing the location information of the terminal device with a network device; the network device belongs to the second communication network; After the terminal device falls back from the first communication network to the second communication network and before initiating a voice call, the terminal device has successfully registered with the second communication network.

6. The method according to claim 5, characterized in that The location information of the terminal device includes an identifier of a tracking area where the terminal device is currently located.

7. The method according to claim 5, characterized in that The first field is used to indicate that the TAU request is initiated by the terminal device when redirection to the first cell fails.

8. The method according to claim 5, characterized in that The method further comprises: In the case where there is a voice call request initiated to the terminal device, paging is initiated to the terminal device.

9. A terminal device, characterized in that: include: Processor and memory; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the terminal device executes the method according to any one of claims 1 to 4.

10. A core network device, characterized in that: include: Processor and memory; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the core network device executes the method according to any one of claims 5 to 8.

11. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented; or the method according to any one of claims 5 to 8 is implemented.

12. A computer program product, characterized in that The computer program product includes computer program codes, and when the computer program codes are executed on a computer, the computer is enabled to implement the method according to any one of claims 1 to 4; or implement the method according to any one of claims 5 to 8.

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