Communication method, terminal equipment and chip system

Abstract

The embodiment of the invention provides a communication method, terminal equipment and a chip system, and relates to the field of terminal equipment communication. The method can improve the call success rate of the terminal device. The method comprises: a user equipment (UE) resides in an NR network. The UE receives an operation of a user on an interface of the UE for de-enabling the 5G communication capability of the UE. The UE resides in a first LTE cell and sends a TAU request to the first LTE cell. And receiving a second operation of the user on the interface of the UE, wherein the second operation is used for enabling the 5G communication capability of the UE. Under the condition that the UE meets the preset condition, the UE resides in a first NR cell and sends a first registration request to the first NR cell, and the first registration request carries indication information used for indicating that the registration type is initial registration.

Description

[0001] This application claims priority to a Chinese patent application filed with the State Intellectual Property Office on October 31, 2023, with application number 202311445314.8 and invention name “A communication method, user equipment and chip system”, the entire contents of which are incorporated by reference in this application. Technical Field

[0002] The present application relates to the field of terminal device communications, and specifically to a communication method, terminal device and chip system. Background Art

[0003] During operation, terminal devices often change their residence between networks of different standards.

[0004] Exemplarily, the terminal device can perform the above-mentioned frequent network change and residence under the frequent operation of the user on the 5G network switch. For example, when the terminal device resides in the 5G network, the user turns off the 5G network switch, and the terminal correspondingly changes to reside in other networks, such as changing to reside in the 4G network. Then the user turns on the 5G network switch again, and the terminal correspondingly re-resides in the 5G network.

[0005] In the scenario where the UE frequently changes its network residence as described above, there may be a problem that even if the terminal successfully re-residents on the 5G network, it may not be able to receive voice calls or text messages for a long time. Summary of the invention

[0006] Some embodiments of the present application provide a communication method, a terminal device (also referred to as a user device in this article), and a chip system to improve the call success rate of the terminal device. To achieve the above technical objectives, the present application adopts the following technical solutions:

[0007] In a first aspect, a communication method is provided, the method comprising: a user equipment UE resides in an NR network. The UE receives a first operation of a user on an interface of the UE, the first operation being used to disable the 5G communication capability of the UE. After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU process to the first LTE cell, the TAU process comprising the UE sending a TAU request to the first LTE cell. After receiving the first operation, the UE receives a second operation of a user on an interface of the UE, the second operation being used to enable the 5G communication capability of the UE. After receiving the second operation, the UE resides in the first NR cell and sends a first registration request to the first NR cell if the UE meets a preset condition, the first registration request carrying indication information for indicating that the registration type is initial registration initial registration. Among them, the UE meets the preset condition including: before the UE sends the first registration request to the first NR cell, the TAU process is in progress. In this example, the UE resides in the NR network, which may include the UE residing in a cell of the NR network, and the UE has completed registration with the NR network device. In different implementations, when the UE resides in the NR network, the NR cell in which it resides may be the aforementioned first NR cell, or may be another NR cell different from the aforementioned first NR cell.

[0008] Based on this solution, when the UE receives the second operation from the user and needs to re-resident on the NR network, it can initiate an initial registration process to the NR network according to the satisfaction of preset conditions. This avoids the problem that the TAU request is not carried in the registration request due to the TAU process in the LTE network not being completed, so that the UE cannot normally receive voice calls or text messages on the NR network. Based on this initial registration process, regardless of whether the TAU process in the LTE network is completed, the UE can register with the NR network and synchronize information between the UE and the network side, so that if the registration is successful, the UE can receive voice calls or text messages through the first NR cell.

[0009] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the UE is preparing to send the first registration request to the first NR cell, or when the UE receives the second operation, the TAU process is in progress. In this way, the specific implementation of the TAU process in progress is clarified.

[0010] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the modem in the UE receives a second instruction, the TAU process is in progress, and the second instruction is a message sent by the application processor AP in the UE to the modem after the UE receives the second operation. In this way, it is clarified that the TAU process is in progress, corresponding to the modem receiving a message sent by the AP indicating the second operation input by the user.

[0011] Optionally, the TAU process being in progress includes: the UE has not received a TAU reject message sent by the first LTE cell, nor has it received a TAU accept message sent by the first LTE cell. In this way, the TAU process being in progress corresponds to the UE not receiving a response corresponding to the TAU request.

[0012] Optionally, the 5G communication capability of the UE includes the ability of the UE to communicate with a 5G network of an independent network SA. In some embodiments, the UE may also have 4G communication capability. In other embodiments, the UE may also have NSA communication capability.

[0013] Optionally, the UE receives a second operation performed by the user on the interface of the UE, including: after the UE sends the TAU request to the first LTE cell, the UE receives the second operation performed by the user on the interface of the UE.

[0014] Optionally, the modem in the UE receives the second instruction, including: after the modem in the UE sends the TAU request to the first LTE cell, the modem receives the second instruction.

[0015] Optionally, the UE camping on the first LTE cell includes: after the modem in the UE receives a first instruction, the UE camps on the first LTE cell. The first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

[0016] In the implementation of the solution provided in the first aspect, the solution provided in this application is limited to an example in which the UE frequently changes its residence between the 5G network and the 4G network according to the user turning on or off the 5G network switch. In the corresponding scenario of the solution provided in the following second aspect, the UE can avoid the problem of being unable to be called after re-resident on the 5G network when the UE frequently changes its residence between the 5G network and the 4G network due to other reasons.

[0017] In a second aspect, a communication method is provided, the method comprising: a user equipment UE resides in an NR network. When the UE reselects to an LTE network, or the UE is redirected from the NR network to the LTE network, or the UE is switched from the NR network to the LTE network, or the UE is executing to disable the 5G communication capability of the UE, the UE resides in a first LTE cell and initiates a TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell. When the UE reselects to the NR network, or the UE is redirected from the LTE network to the NR network, or the UE is switched from the LTE to the NR network, or the UE is executing to enable the 5G communication capability of the UE, and the UE meets a preset condition, the UE resides in the first NR cell and sends a first registration request to the first NR cell, and the first registration request carries indication information for indicating that the registration type is initial registration. Wherein, the UE meets the preset condition including: before the UE sends the first registration request to the first NR cell, the TAU process is in progress.

[0018] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the UE is preparing to send the first registration request to the first NR cell, or when the UE is executing to enable the UE's 5G communication capability, the TAU process is in progress.

[0019] Optionally, the UE's execution of enabling the UE's 5G communication capability includes: the UE receives a second operation by the user on the UE's interface, and the second operation is used to enable the UE's 5G communication capability. The UE's execution of disabling the UE's 5G communication capability includes: the UE receives a first operation by the user on the UE's interface, and the first operation is used to disabling the UE's 5G communication capability. For example, the first operation may be an operation by the user on a 5G network switch button on the UE interface.

[0020] Optionally, the case where the UE enables the 5G communication capability of the UE also includes: a modem in the UE receives a second instruction, and the second instruction is a message sent by the AP in the UE to the modem after the UE receives the second operation. The case where the UE disables the 5G communication capability of the UE also includes: the modem in the UE receives a first instruction, and the first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

[0021] Optionally, the TAU process in progress includes: the UE has not received a TAU reject message sent by the first LTE cell, and has not received a TAU accept message sent by the first LTE cell.

[0022] Optionally, the 5G communication capability of the UE includes the ability of the UE to communicate with a 5G network of an independent network SA.

[0023] In a third aspect, a communication method is provided, the method comprising: a user equipment UE resides in an NR network. The UE receives a first operation of a user on an interface of the UE, the first operation being used to disable the 5G communication capability of the UE. After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU process to the first LTE cell, the TAU process comprising the UE sending a TAU request to the first LTE cell. After receiving the first operation, the UE receives a second operation of a user on an interface of the UE, the second operation being used to enable the 5G communication capability of the UE. After receiving the second operation, if the UE meets a preset condition, the UE resides in the first NR cell and sends a second registration request to the first NR cell, the second registration request carrying the TAU request. The UE meeting the preset condition comprises: before the UE sends the second registration request to the first NR cell, the TAU process is in progress.

[0024] In the implementation of the solution provided in the third aspect, the UE can directly carry the TAU request in the registration request to the 5G network when the TAU process is in progress. This enables the re-resident 5G network to synchronize with the UE according to the registration request, and then after the UE successfully resides in the 5G network, it can be called smoothly.

[0025] Optionally, the second registration request carries the TAU request, including: the second registration request includes a field indicating that Eps_nas_msg is 72. It can be understood that when the TAU request is carried in the registration request, the UE may carry the information of the TAU request in the information corresponding to the configuration value 72 in the Eps_nas_msg field.

[0026] Optionally, the UE satisfies the preset condition further including: before the UE sends the second registration request to the first NR cell, the UE is in a 5GMM-IDLE state. Alternatively, the UE satisfies the preset condition further including: before the UE sends the second registration request to the first NR cell, the UE is in a 5GMM-IDLE state, and the UE has received an indication from the NR network indicating that the NR network supports the N26 interface.

[0027] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the UE is preparing to send the first registration request to the first NR cell, or when the UE receives the second operation, the TAU process is in progress.

[0028] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the modem in the UE receives a second instruction, the TAU process is in progress, and the second instruction is a message sent by the application processor AP in the UE to the modem after the UE receives the second operation.

[0029] Optionally, the TAU process in progress includes: the UE has not received a TAU reject message sent by the first LTE cell, and has not received a TAU accept message sent by the first LTE cell.

[0030] Optionally, the 5G communication capability of the UE includes the ability of the UE to communicate with a 5G network of an independent network SA.

[0031] Optionally, the UE receives a second operation performed by the user on the interface of the UE, including: after the UE sends the TAU request to the first LTE cell, the UE receives the second operation performed by the user on the interface of the UE.

[0032] Optionally, the modem in the UE receives the second instruction, including: after the modem in the UE sends the TAU request to the first LTE cell, the modem receives the second instruction.

[0033] Optionally, the UE camping on the first LTE cell includes: after the modem in the UE receives a first instruction, the UE camps on the first LTE cell. The first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

[0034] In a fourth aspect, a communication method is provided, the method comprising: a UE resides in a first NR cell. When the UE reselects to an LTE network, or the UE is redirected from the NR network corresponding to the first NR cell to an LTE network, or the UE switches from the NR network to the LTE network, or the UE is executing to disable the 5G communication capability of the UE, the UE resides in the first LTE cell and initiates a TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell. When the UE reselects to an NR network, or the UE is redirected from the LTE network to the NR network, or the UE network is executing to enable the 5G communication capability of the UE, and the UE meets a preset condition, the UE resides in the first NR cell and sends a second registration request to the first NR cell, and the second registration request carries the TAU request. Wherein, the UE meets the preset condition including: before the UE sends the second registration request to the first NR cell, the TAU process is in progress.

[0035] Optionally, before the UE sends the first registration request to the first NR cell, the TAU process is in progress, including: when the UE is preparing to send the first registration request to the first NR cell, or when the UE is executing to enable the UE's 5G communication capability, the TAU process is in progress.

[0036] Optionally, the UE's execution of enabling the UE's 5G communication capability includes: the UE receives a second operation by the user on the UE's interface, and the second operation is used to enable the UE's 5G communication capability. The UE's execution of disabling the UE's 5G communication capability includes: the UE receives a first operation by the user on the UE's interface, and the first operation is used to disabling the UE's 5G communication capability.

[0037] Optionally, the case where the UE enables the 5G communication capability of the UE also includes: a modem in the UE receives a second instruction, and the second instruction is a message sent by the AP in the UE to the modem after the UE receives the second operation. The case where the UE disables the 5G communication capability of the UE also includes: the modem in the UE receives a first instruction, and the first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

[0038] Optionally, the TAU process in progress includes: the UE has not received a TAU reject message sent by the first LTE cell, and has not received a TAU accept message sent by the first LTE cell.

[0039] Optionally, the 5G communication capability of the UE includes the ability of the UE to communicate with a 5G network of an independent network SA.

[0040] The technical solutions provided in the following fifth and sixth aspects, by reasonably configuring the timer, allow the UE to have more time to complete the TAU process before initiating registration with the 5G network, thereby increasing the probability of carrying a TAU request in the 5G network registration request. This can also increase the probability that the UE can receive a called call after re-resident on the 5G network. The fifth aspect provides a solution for configuring the timer in the AP in a scenario where the UE frequently re-resident on the network due to user operations; the sixth aspect provides a solution for configuring the timer in the modem in a scenario where the UE frequently re-resident on the network due to user operations.

[0041] In a fifth aspect, a communication method is provided, the method comprising: a user equipment UE resides in an NR network. The UE receives a first operation of a user on an interface of the UE, and the first operation is used to disable the 5G communication capability of the UE. After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell. After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, and the second operation is used to enable the 5G communication capability of the UE. The second operation is received after a first time length after the UE receives the first operation, or the second operation is received after the TAU process is successful. After receiving the second operation, the UE resides in the first NR cell and sends a third registration request to the first NR cell, and the third registration request carries the TAU request.

[0042] Optionally, after the UE receives the first operation, the method further includes: the AP of the UE starts a first timer, and the timing duration of the first timer is the first duration. During the timing of the first timer, the UE enables the 5G communication capability of the UE to be configured as inoperable.

[0043] Optionally, the method further includes: when the timing of the first duration ends or a TAU Accept message corresponding to the TAU request is received, exiting the first timer. After exiting the first timer, the UE enables the 5G communication capability of the UE to be configured as operable.

[0044] Optionally, the UE receives the second operation, including: after the first timer exits, the UE receives the second operation.

[0045] In a sixth aspect, a communication method is provided, the method comprising: a user equipment UE resides in an NR network. The UE receives a first operation of a user on an interface of the UE, and the first operation is used to disable the 5G communication capability of the UE. After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell. After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, and the second operation is used to enable the 5G communication capability of the UE. The second operation is received within a second duration after the UE receives the first operation, or the second operation is received before the TAU process succeeds. After receiving the second duration of the first operation, or after the UE succeeds in the TAU process, the UE resides in the first NR cell and sends a fourth registration request to the first NR cell, and the fourth registration request carries the TAU request.

[0046] Optionally, after sending the TAU request, the method further includes: the modem of the UE starts a second timer, the timing duration of the second timer being the second duration. During the timing of the second timer, the modem of the UE caches the received information corresponding to the second operation.

[0047] Optionally, the information corresponding to the second operation includes a second instruction, and the second instruction is a message sent by the application processor AP in the UE to the modem after the UE receives the second operation. After the UE receives the second operation, the method further includes: the modem of the UE receives the second instruction.

[0048] Optionally, before the UE resides in the first NR cell, the method also includes: when the timing of the second timer of the UE ends, or when a TAU Accept message corresponding to the TAU request is received, the UE exits the second timer.

[0049] Optionally, after receiving the second duration of the first operation, or after the TAU process succeeds, the UE resides in the first NR cell and sends a fourth registration request to the first NR cell, including: after the second timer exits, the UE resides in the first NR cell and sends a fourth registration request to the first NR cell.

[0050] In a seventh aspect, a communication method is provided, the method comprising: a user equipment UE resides in a first network. The UE receives a first operation of a user on an interface of the UE, the first operation being used to disable the communication capability of the UE in the first network. After receiving the first operation, the UE resides in a cell of a second network and initiates a first mobility location update process to the cell of the second network, the first mobility location update process comprising the UE sending a first mobility location update request to the cell of the second network. The format of the second network is different from the format of the first network. After receiving the first operation, the UE receives a second operation of a user on an interface of the UE, the second operation being used to enable the communication capability of the UE in the first network. After receiving the second operation, the UE resides in a cell of the first network and sends a first registration request to the cell of the first network if the UE meets a preset condition, the first registration request carrying indication information for indicating that the registration type is initial registration. Wherein, the UE meeting the preset condition comprises: before the UE sends the first registration request to the cell of the first network, the mobility location update process is in progress.

[0051] Optionally, when the first mobility location update process is completed, the first registration request is an MRU type registration request, and the first registration request carries at least part of the information of the first mobility location update request.

[0052] Optionally, the first network is a 5G network, the second network is a 4G network, the first mobility location update process is a TAU process, and the first mobility location update request is a TAU request.

[0053] In an eighth aspect, a communication method is provided, the method comprising: a user equipment UE resides in a first network. When the UE reselects to a second network, or the UE is redirected from the first network to the second network, or the UE is switched from the first network to the second network, or the UE is disabling the communication capability of the UE in the first network, the UE resides in a cell of the second network and initiates a mobility location update process to the cell of the second network, the mobility location update process comprising the UE sending a mobility location update request to the cell of the second network. When the UE reselects to the first network, or the UE is redirected from the second network to the first network, or the UE is switched from the second network to the first network, or the UE is enabling the communication capability of the UE in the first network, and the UE meets a preset condition, the UE resides in the cell of the first network and sends a first registration request to the cell of the first network, the first registration request carrying indication information for indicating that the registration type is initial registration. The UE meeting the preset condition includes: before the UE sends the first registration request to the cell of the first network, the mobility location update process is in progress.

[0054] In a ninth aspect, a terminal device is provided, the terminal device comprising: a memory and a processor for storing instructions. The processor is used to call and execute the instructions in the memory, so that the terminal device performs the method provided in the first aspect and any possible implementation thereof, or the terminal device performs the method provided in the second aspect and any possible implementation thereof, or the terminal device performs the method provided in the third aspect and any possible implementation thereof, or the terminal device performs the method provided in the fourth aspect and any possible implementation thereof, or the terminal device performs the method provided in the fifth aspect and any possible implementation thereof, or the terminal device performs the method provided in the sixth aspect and any possible implementation thereof, or the terminal device performs the method provided in the seventh aspect and any possible implementation thereof, or the terminal device performs the method provided in the eighth aspect and any possible implementation thereof.

[0055] In a tenth aspect, a chip system is provided, the chip system comprising: a processing circuit, a receiving pin and a transmitting pin. The receiving pin, the transmitting pin and the processing circuit communicate with each other through an internal connection path, and the processing circuit executes the method provided in the first aspect and any possible implementation thereof, or the method provided in the second aspect and any possible implementation thereof, or the method provided in the third aspect and any possible implementation thereof, or the method provided in the fourth aspect and any possible implementation thereof, or the method provided in the fifth aspect and any possible implementation thereof, or the method provided in the sixth aspect and any possible implementation thereof, or the method provided in the seventh aspect and any possible implementation thereof, or the method provided in the eighth aspect and any possible implementation thereof, to control the receiving pin to receive a signal and control the transmitting pin to send a signal.

[0056] In the eleventh aspect, a chip system is provided, which includes a processor, for supporting a terminal device to implement a method as provided in the first aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the second aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the third aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the fourth aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the fifth aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the sixth aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the seventh aspect and any possible implementation thereof, or for supporting a terminal device to implement a method as provided in the eighth aspect and any possible implementation thereof.

[0057] Optionally, the processor includes a modem processor.

[0058] In the twelfth aspect, the present application also provides a computer-readable storage medium, including computer instructions. When the computer instructions are executed on an electronic device, the electronic device executes the method provided in the above-mentioned first aspect and any possible implementation thereof, or executes the method provided in the second aspect and any possible implementation thereof, or executes the method provided in the third aspect and any possible implementation thereof, or executes the method provided in the fourth aspect and any possible implementation thereof, or executes the method provided in the fifth aspect and any possible implementation thereof, or executes the method provided in the sixth aspect and any possible implementation thereof, or executes the method provided in the seventh aspect and any possible implementation thereof, or executes the method provided in the eighth aspect and any possible implementation thereof.

[0059] In the thirteenth aspect, the present application also provides a computer program product. When the computer program product is run on a computer, it enables the computer to execute the method provided in the above-mentioned first aspect and any possible implementation thereof, or execute the method provided in the second aspect and any possible implementation thereof, or execute the method provided in the third aspect and any possible implementation thereof, or execute the method provided in the fourth aspect and any possible implementation thereof, or execute the method provided in the fifth aspect and any possible implementation thereof, or execute the method provided in the sixth aspect and any possible implementation thereof, or execute the method provided in the seventh aspect and any possible implementation thereof, or execute the method provided in the eighth aspect and any possible implementation thereof.

[0060] It can be understood that the solutions provided in the second aspect to the thirteenth aspect of the present application can respectively correspond to the first aspect and any possible design thereof, so the beneficial effects that can be achieved are similar and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 A schematic diagram of a network architecture provided for an embodiment of the present application;

[0062] Figure 2 A schematic diagram of a voice call scenario provided in an embodiment of the present application;

[0063] Figure 3 A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0064] Figure 4 A schematic diagram of the interface switching logic of a user input operation provided in an embodiment of the present application;

[0065] Figure 5 A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0066] Figure 6 A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0067] Figure 7 A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0068] Figure 8 A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0069] Fig. 9 A schematic diagram of an interface switching provided in an embodiment of the present application;

[0070] Fig.10A schematic diagram of an interactive process of a communication method provided in an embodiment of the present application;

[0071] Fig.11 A schematic diagram of the hardware composition of a terminal device provided in an embodiment of the present application;

[0072] Fig.12 A schematic diagram of the software structure of a terminal device provided in an embodiment of the present application;

[0073] Fig.13 A schematic diagram of the composition of a terminal device provided in an embodiment of the present application;

[0074] Fig.14 A schematic diagram of the composition of a chip system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0075] Currently, terminal devices can provide users with communication services such as calls and network data by accessing the network.

[0076] Exemplary, reference Figure 1 , is a schematic diagram of a network architecture provided as an example in an embodiment of the present application.

[0077] like Figure 1 As shown, the network architecture may include terminal equipment, LTE, NR, a core network, and an IP Multimedia Subsystem (IMS) or the Internet.

[0078] The following is a detailed introduction:

[0079] (1) Terminal: It can also be called User Equipment (UE), User Terminal, Mobile Station (MS), Mobile Terminal (MT), etc. The terminal can be a mobile phone or a wearable device (such as a smart watch).

[0080] In some embodiments of the present application, the terminal device may be configured with an application processor (AP) and a modem processor (Modem, also referred to as a baseband processor, abbreviated as MD).

[0081] The AP can support the interface display capability of the terminal device. The AP can also execute corresponding responses according to the user operations received by the terminal device on the interface. In addition, the MD can support the digital processing capability of the terminal device.

[0082] In an embodiment of the present application, the terminal device may have 5G communication capability. Exemplarily, the 5G communication capability may include: the terminal device has the ability to communicate with a 5G network device in 5G standalone (SA) networking. In other embodiments, the terminal device may also have 5G non-standalone (NSA) networking capability.

[0083] (2) LTE: It can be understood as the wireless access network of the 4G network. In the LTE network (commonly known as the 4G network), due to the evolution relationship, the access network part is called the Evolved UMTS Terrestrial Radio Access Network (Evolved UMTS Terrestrial Radio Access Network, E-UTRAN). In this application, the meaning of LTE is the same as that of E-UTRAN, both referring to the access network part of the 4G network. Terminal devices can access LTE through 4G base stations (such as eNB).

[0084] (3) NR: It can be understood as the radio access network of the 5G network. In the 5G network, the access network part is called the Next Generation Radio Access Network (NG-RAN or NG RAN). In this application, the meaning of NR is the same as that of NG-RAN (or NG RAN), both referring to the access network part of the 5G network. Terminal devices can access LTE through 5G base stations (such as gNB). In this application, the 5G network can also be referred to as the NR network.

[0085] It is understandable that both LTE and NR are access networks. The access network is responsible for connecting the majority of end users (End Users) to the core network (also known as the backbone network) one level at a time using some kind of wired or wireless connection and communication technology to achieve connection with the network. The access network is the edge of the entire network, the part closest to the user, and is usually called the "last mile."

[0086] (4) Core network: The main functions are to provide user connections, user management, and service bearing. It provides an interface to the external network as a bearer network. The establishment of user connections includes functions such as mobility management (MM), call management (CM), switching / routing, and recording notification (combined with intelligent network services to complete the connection relationship with intelligent network peripheral devices).

[0087] It is understandable that the core network of the 4G network is the Evolved Packet Core (EPC) network. The EPC network is the core network of the 4G mobile communication network. It belongs to the core network category and has traditional capabilities of mobile networks such as user contract data storage, mobility management, and data exchange, and can provide users with ultra-high-speed Internet experience. The core network of the 5G network is 5GCore (abbreviated as 5GC). 5GC will use general network function virtualization equipment to replace the dedicated communication equipment of the 4G network.

[0088] It should be noted that Figure 1 The core network in the network architecture shown can be obtained by integrating EPC and 5GC. That is to say, the core network in the network architecture can include both network elements in EPC and network elements in 5GC. For example, the core network in the network architecture may include access and mobility management function (AMF) network element, mobility management entity (MME) network element, serving gateway (SGW) network element, packet data network gateway (PGW) network element, session management function (SMF) network element, user plane function (UPF) network element, unified data management function (UDM) network element and home subscriber server (HSS) network element, etc.

[0089] In some embodiments of the present application, the core network in the network architecture may include a converged network element obtained by the network element in the EPC and the network element in the 5GC. For example, SMF+PGW-C, UPF+PGW-U, UDM+HSS, etc. Among them, PGW-C is the control plane node of the PGW network element, and PGW-U is the user plane node of the PGW network element.

[0090] In some embodiments of the present application, Figure 1The core network in the network architecture shown may include a Proxy Session Border Control (PSBC) network element, which is a combined network element that integrates Session Border Control (SBC), Proxy-CSCF (P-CSCF), Access Transfer Control Function (ATCF), and Access Transfer Gateway (ATGW). As an SBC network element, it connects the IMS core network / soft switch network with the external user access area, completes the service access of IMS / soft switch users, realizes the interoperability of user services under different network environments, ensures the security of IMS / soft switch networks, and supports QoS management, CAC traffic control, media management, CDR media call details, and other functions.

[0091] Each network element in the core network can also be called a functional entity, which can be a network element implemented on dedicated hardware, a software instance running on dedicated hardware, or an instance of a virtualized function on an appropriate platform.

[0092] It should be understood that the names of all network elements in this application are only examples. In future communications, such as 6G, they can also be called other names, or in future communications, such as 6G, the network elements involved in this application can also be replaced by other entities or devices with the same functions, etc., and this application does not limit this. A unified explanation is made here, and no further details will be given later. Optionally, the various network elements in the embodiments of the present application can be communication devices, or chips or chip systems that can be operated in the communication device, etc., and this embodiment of the present application does not limit this.

[0093] Understandably, Figure 1 The core network in the network architecture shown may also include other devices, network elements, network entities or network subsystems, such as a policy control function (PCF) network element, which is not limited in this application. It should be noted that this application does not limit the distribution of each network element in the core network. The specific distribution method can be referred to in relevant technical documents, which is not described in detail in this application.

[0094] (5) IMS is a network architecture that provides voice and multimedia communication services (e.g., voice, video, and text messaging) based on the Internet Protocol (IP) network. IMS enables secure and reliable multimedia communications between different devices on different networks. The architecture model provides a unified infrastructure and common mechanisms for controlling, operating, routing, and managing sessions, as well as implementing authentication, authorization, and accounting controls. The IMS specifications include widely used Internet Engineering Task Force (IETF) recommendations. For example, the Session Initialization Protocol (SIP) is used for session control signaling.

[0095] Internet generally refers to the Internet, also known as the international network, which refers to a huge network of networks connected in series. These networks are connected by a set of common protocols to form a logical single huge international network. From the perspective of network communication, the Internet is a data communication network that connects computer networks in various countries, regions, and institutions around the world using the Transmission Control Protocol (TCP) / Internet Protocol (IP).

[0096] It should be noted that Figure 1 The network architecture shown is not limited to including only the devices and networks shown in the figure, but may also include other devices not shown in the figure, and this application will not give examples one by one.

[0097] Based on the terminal equipment Figure 1 The network architecture shown in the figure is used to implement call service as an example, wherein the access network equipment and the core network equipment can be collectively referred to as network equipment.

[0098] refer to Figure 2 , which is a voice call scenario provided in an embodiment of the present application.

[0099] In this Figure 2 In the example, the terminal device 10 can be connected to the IMS through the network device 11. The terminal device 20 can be connected to the IMS through the network device 21. Among them, the network device 11 is the network device corresponding to the cell where the terminal device 10 currently resides, and the network device 21 is the network device corresponding to the cell where the terminal device 20 currently resides. In some embodiments of the present application, the network device 11 and the network device 21 can be the same network device.

[0100] It should be noted that the network device in the embodiment of the present application may be a device for communicating with a terminal device. For example, the network device may include Figure 1 The device corresponding to the access network and / or the device corresponding to the core network shown in the figure. The device corresponding to the access network may also be referred to as the access network device. The device corresponding to the core network may also be referred to as the core network device.

[0101] Take the network device including the access network device as an example. In some embodiments, the network device may include a base station of a 4G network, such as an eNB. In other embodiments, the network device may include a base station of a 5G network, such as a gNB.

[0102] Taking the network device including the core network device as an example, in some embodiments, the network device may include a 4G core network device. In other embodiments, the network device may include a 5G core network device.

[0103] like Figure 2 As shown, the terminal device 10 can transmit voice data with the terminal device 20 through the network device 11, the IMS and the network device 21. In some embodiments of the present application, the terminal device 10 can be the party that initiates the voice call to request a voice call with the terminal device 20. In some other embodiments of the present application, the terminal device 20 can be the party that initiates the voice call to request a voice call with the terminal device 10.

[0104] refer to Figure 3 , is a schematic diagram of an interactive flow of a communication method provided in an embodiment of the present application. Figure 3 The scenario shown provides a specific implementation of a terminal device accessing / changing a resident network in an actual scenario. Based on this, the terminal device can provide communication services such as calls and network data after successfully accessing / changing the resident network. In the following description, eNB can correspond to Figure 1 The access network equipment of the LTE network shown in FIG. 1 is a 4G base station. The gNB can correspond to the following: Figure 1 The access network equipment of the 5G network shown is a 5G base station. The core network equipment can be a logical device set, and the core network equipment can specifically include a 4G core network equipment and a 5G core network equipment.

[0105] like Figure 3 As shown, the process may include:

[0106] S301. UE and gNB perform 5G RRC access.

[0107] Exemplarily, when there are multiple indicated networks (such as 4G, 5G, etc.) at the current location, the UE can give priority to accessing a high-standard (such as 5G) network.

[0108] In some embodiments, the UE can achieve 5G RRC access to the gNB by initiating a random access procedure to the gNB.

[0109] When the UE successfully accesses the gNB, the UE can interact with the 5G core network device through the gNB. For example, the UE can execute the following S302 to initiate a registration process to the 5G core network device through the gNB. As a result, when the gNB successfully registers with the 5G core network, the UE can provide the user with 5G network communication services through the gNB and the 5G core network device.

[0110] S302. The UE registers to the 5G network through the gNB.

[0111] Exemplarily, the registration to the 5G network may specifically include: the UE initiates a registration process to the 5G core network device through the gNB. In this process, the gNB may provide signaling or message forwarding between the UE and the 5G core network device. For example, the forwarding may be transparent transmission.

[0112] like Figure 3 As shown, in some embodiments, the S302 may specifically include:

[0113] The UE sends a registration request 31 to the gNB, and the gNB sends a registration request 31 to the core network device. For example, the registration request 31 may include a Registration Request message. In some implementations, the registration request 31 may carry a 5GS registration type value.

[0114] Take the UE powering on and executing S302 as an example. In this way, the UE can send a registration request 31 to implement initial registration. In this example, the 5GS registration type value carried in the registration request 31 can be 001, corresponding to a request to perform initial registration.

[0115] Take the case where the UE re-residents on the 5G network from other networks to execute S302 as an example. In this way, the UE can send a registration request 31 to implement mobility registration updating (MRU). In this example, the 5GS registration type value carried in the registration request 31 can be 010, corresponding to a request to perform a mobility registration update.

[0116] like Figure 3As shown, after the UE sends the registration request 31, it can receive a registration acceptance message 32 from the gNB. Exemplarily, the registration acceptance message 32 can be sent by the core network device to the gNB and transmitted by the gNB to the UE. For example, the registration acceptance message 32 can include a Registration Accept message.

[0117] In some implementations, the registration acceptance message 32 may carry an indication that the network supports the N26 interface. It is understandable that after the 5G core network is deployed separately, for UEs that only support a single registration mode, frequent network change residency (reselection / redirection) between 4G and 5G networks will be necessary. From the perspective of UE connectivity alone, IP address continuity is required so that the terminal is as seamless as possible when moving between systems, especially for voice services. The N26 interface enables the network to achieve this continuity because it enables the network to exchange terminal (UE) mobility management (MM) and session management (SM) states.

[0118] In this way, the UE is registered with the 5G network through the interaction of the registration request 31 and the registration acceptance message 32. Then, the UE can provide communication services to the user through the 5G network. For example, the UE can provide the following services through the 5G network: Figure 2 Voice call service shown.

[0119] In some implementations, the UE may also send a registration complete message to the core network through the gNB after receiving the registration accept message 32. For example, the registration complete message may include a Registration Complete message.

[0120] In an embodiment of the present application, the UE can communicate with the gNB by accessing the NR cell (ie, 5G cell) of the gNB. In some embodiments of the present application, after the UE registers to the 5G network, it can communicate with the 5G network through the NR cell of the gNB. When the UE successfully establishes an RRC connection with the gNB, it can also be referred to as the UE residing in the NR cell. Correspondingly, if the UE resides in the NR network, it means that the UE has completed the RRC access to the gNB of the NR network and has completed the registration with the core network device of the NR network.

[0121] It is understandable that the interaction between the UE and the core network device can be forwarded and transparently transmitted by the corresponding base station. Therefore, in the embodiment of the present application, the message sent by the UE to each 5G network device can also be described as the message sent by the UE to the NR cell to which it has accessed. Similarly, the UE receiving a message from the 5G network device can also be described as the UE receiving a message from the corresponding NR cell.

[0122] As described in S302 about the N26 interface, during the operation of the UE, changes in residency between the 4G network and the 5G network often occur.

[0123] In some embodiments, when the UE's 5G communication capability is changed, such as when the 5G communication capability is turned off, the UE can access other networks (such as 4G networks) to continue to provide communication services to users. Figure 3 The "turning off the 5G network" shown can be understood as the UE's 5G communication capability being turned off / disabled. For example, the UE's 5G communication capability being turned off / disabled may include: with user participation, such as receiving a user clicking a button of the 5G communication function to turn off the UE's 5G communication capability; or, without user participation, the UE disabling the 5G communication capability, such as when the UE has a temporary failure, the self-healing mechanism is triggered, and during the execution of the self-healing mechanism, the UE disabling the 5G communication capability.

[0124] In other embodiments, when the UE's 5G communication capability remains unchanged, the UE may also attempt to access other networks (such as 4G networks) to continue to provide communication services to users. For example, the UE may attempt to access the 4G network through the network reselection process. Figure 3 As shown, the UE changes to reside in another network (such as a 4G network) according to a network change indication A sent by a network device (such as a currently connected gNB).

[0125] The network change indication A may include: a network redirection indication (such as an RRCConnectionRelease message carrying a redirectedCarrierInfo indication), etc. The redirectedCarrierInfo in the RRCConnectionRelease message may include a standard identifier (or system identifier) ​​of the redirected 4G network, and a frequency.

[0126] In some other implementations, the network change indication A may include: a network switching indication (such as a Handover message), etc.

[0127] It should be noted that the UE can change its residence from the 5G network to the 4G network by Figure 3 Alternatively, it may be triggered by shutting down the 5G network as shown in Figure 3 As shown, it is triggered by receiving a network change indication A; or, as described in the above example, the UE can also actively change from the 5G network to the 4G network based on the network reselection process.

[0128] Thus, the UE may execute the following S303 to attempt to access the 4G network. In some implementations, the UE may disconnect the RRC connection established with the gNB in ​​S301 before executing S303.

[0129] S303: UE and eNB perform 4G RRC access.

[0130] Exemplarily, the UE may initiate random access to the eNB of the 4G network to achieve the 4G RRC access. When the UE successfully accesses the eNB, the UE may interact with the 4G core network device through the eNB.

[0131] S304. The UE registers to the 4G network through the eNB.

[0132] Exemplarily, the S304 may specifically include:

[0133] 1) The UE sends a TAU request 33 to the eNB, and the eNB sends a TAU request 33 to the core network device. The TAU may be a Tracking Area Update. Exemplarily, the TAU request 33 may include a TAU Request message.

[0134] 2) The UE receives a TAU accept message 34. Exemplarily, the TAU accept message 34 may include a TAU Accept message.

[0135] In this way, through S304, the UE can change its residence to the 4G network.

[0136] In the present application, through the TAU process shown in S304, when the UE moves from one Tracking Area (TA) to another TA, the network can change the TA information of the UE accordingly, so that the UE can continue to provide communication services to the UE on the 4G network.

[0137] In an embodiment of the present application, the UE can communicate with the eNB by accessing the LTE cell (i.e., the 4G cell) of the eNB. In some embodiments of the present application, after the UE registers to the 4G network, it can communicate with the 4G network through the first LTE cell of the eNB. Exemplarily, when the UE successfully establishes an RRC connection with the eNB, it can also be said that the UE resides in the first LTE cell.

[0138] Correspondingly, in the above S303-S304, the message sent by the UE to each 4G network device can also be described as the message sent by the UE to the first LTE cell. Similarly, the message received by the UE from the 4G network device can also be described as the message received by the UE from the first LTE cell.

[0139] In this Figure 3 In the scenario shown, after the UE changes to reside on the 4G network, it can change the network again to reside on the 5G network.

[0140] In some embodiments, when the UE's 5G communication capability changes, such as when the 5G communication capability is turned on, the UE can re-resident on the 5G network to continue to provide communication services to the user. Figure 3 The "turn on 5G network" shown can be understood as the UE's 5G communication capability being turned on / enabled. For example, the change of the UE's 5G communication capability may include: with user participation, such as receiving a user clicking a button of the 5G communication function to turn on the UE's 5G communication capability; or, without user participation, the UE enables the 5G communication capability, such as when the UE resides in a 4G network, triggering a self-healing mechanism, and in the process of executing the self-healing mechanism, the UE enables the 5G communication capability.

[0141] In other embodiments, when the UE's 5G communication capability remains unchanged, the UE may also attempt to access other networks (such as a 5G network) to continue to provide communication services to the user. For example, the UE may attempt to access the 5G network through a network reselection process. Figure 3 As shown, the UE changes to reside in another network (such as a 5G network) according to a network change indication B sent by a network device (such as a currently connected eNB).

[0142] Among them, the network change indication B may include: a network redirection indication (such as an RRCConnectionRelease message carrying a redirectedCarrierInfo indication), etc. Among them, the redirectedCarrierInfo in the RRCConnectionRelease message may include the standard identifier (or system identifier) ​​of the redirected 5G network, and the frequency.

[0143] It should be noted that the UE can change its residence from the 4G network to the 5G network by Figure 3 Alternatively, it may be triggered by turning on the 5G network as shown; Figure 3 As shown, it is triggered by receiving a network change indication B; or, as described in the above example, the UE can also actively change its residence from the 4G network to the 5G network based on the network reselection process.

[0144] Correspondingly, the UE may execute the following S305.

[0145] S305. UE and gNB perform 5G RRC access.

[0146] Exemplarily, the UE may also initiate a random access process to the gNB, and upon completion of the random access, implement RRC access to the gNB. It should be noted that, in some embodiments, the NR cell of the 5G network re-accessed by the UE in S305 may be the same as the NR cell accessed in S301-S302. In other embodiments, the NR cell of the 5G network re-accessed by the UE in S305 is different from the NR cell accessed in S301-S302.

[0147] S306. The UE registers to the 5G network through the gNB.

[0148] For example, the UE can initiate a registration process to the 5G core network device through the gNB with which the RRC connection has been established. If the registration is successful, the UE can provide the user with 5G network communication services through the 5G core network device and the gNB.

[0149] As an implementation, Figure 3 As shown, the S306 may specifically include:

[0150] 1) The UE sends a registration request 35 to the gNB. The gNB sends the registration request 35 to a core network device (such as a 5G core network device).

[0151] Exemplarily, the registration request 35 may include a Registration Request message.

[0152] It should be noted that the registration request 35 may carry information of a TAU request. For example, the TAU request in the registration request 35 may correspond to the TAU request 33 in S304. For example, the TAU request in the registration request 35 may include at least part of the information in the TAU request 33. As a possible implementation, the TAU request in the registration request 35 may include information of the corresponding MME entity when the UE accesses the 4G network. In addition, the 5GS registration type value that the registration request 35 may carry may be 010, corresponding to a request to perform a mobility registration update.

[0153] The mechanism for carrying the TAU request in the registration request 35 may be specified in the existing protocol.

[0154] Specifically, section 5.5.1.3 of 3GPP 24.501 stipulates that if the registration process for mobility and periodic registration updates (i.e., MRU (Mobility Registration Updating) and PRU (Periodic Registration Updating)) meets the following three conditions, the UE shall piggyback the tracking area update request (TAU request, also abbreviated as TAU req) message in the EPS NAS message container IE in the Registration Request message sent to the 5G network. The three conditions may include:

[0155] Condition 1: A UE in single registration mode performs an inter-system change from S1 mode to N1 mode;

[0156] The S1 mode can be understood as the LTE standard, and the N1 mode can be understood as the NR standard. The single registration mode can refer to registering in a network of one standard at the same time, compared with the dual registration mode, which is registered in two networks of two standards at the same time.

[0157] Condition 2: If the registration process is started in 5GMM-IDLE mode;

[0158] When the UE receives a network switching indication (such as a Handover message) and initiates a registration process to a 5G cell (specifically, to a 5G network device) in a scenario where the UE switches from a 4G network to a 5G network, the UE does not belong to the 5G MM-IDLE mode.

[0159] When the UE initiates a registration process to the 5G network device in the scenario where the 5G switch is turned on, or redirected from the 4G network to the 5G network (also referred to as redirected from LTE to NR), or reselected from the 4G network to the 5G network (also referred to as reselected from LTE to NR), the UE belongs to the 5G MM-IDLE mode. Exemplarily, the process of redirecting the UE from the 4G network to the 5G network may be triggered after the UE receives the network change indication B.

[0160] Condition 3: The UE has received an indication from the network indicating that the network side supports the N26 interface.

[0161] For example, when the UE initiates an MRU type registration process to an NR cell this time, the UE has received indication information from the NR cell indicating that the network side supports the N26 interface when it last registered with the NR cell. The indication information can indicate that the base station corresponding to the NR cell supports the N26 interface, and supporting the N26 interface means that the base station supports interworking between 4G and 5G networks.

[0162] The relevant content in the 3GPP 24.501 agreement is as follows:

[0163] 5.5.1.3Registration procedure for mobility and periodic registrationupdate If the UE operating in the single-registration mode performs inter-system change from S1 mode to N1 mode, the UE:shall include a TRACKING AREAUPDATE REQUEST message as specified in 3GPP TS24.301

[15] in the EPS NAS message container IE in the REGISTRATION REQUEST message if the Registration procedure is initiated in 5GMM-IDLE mode and the UE has received an "interworking without N26 interface not supported" indication from the network.

[0164] 2) The UE receives a registration acceptance message 36 from the gNB. The registration acceptance message 36 may be sent by the core network device to the gNB. Exemplarily, the registration acceptance message 36 may include a Registration Accept message. In this way, the UE can successfully change to reside on the 5G network.

[0165] In some implementations, the UE may also send a Registration Complete message to a core network device (such as a 5G core network device) through the gNB after receiving the registration acceptance message 36.

[0166] As explained above, in Figure 3 In the scenario shown, in some implementations, the process of the UE changing from a 5G network to a 4G network, or the UE changing from a 4G network to a 5G network, may be triggered by an operation input by a user.

[0167] refer to Figure 4, which is an example of interface switching logic for user input operation. In this example, the UE can display a button 401 for turning on or off the 5G network to the user on the interface. In some implementations, the button 401 can be configured in the UE's settings application. For example, the UE can display a network settings interface 402 of the settings application under the control of the user. The button 401 can be displayed to the user on the interface 402. Through the button 401, the UE can receive the user's operation and correspondingly execute the turning on or off of the 5G network.

[0168] For example, based on the Figure 4 The logic shown in 41 can realize the shutdown of 5G network.

[0169] Take the example that the current 5G network switch in interface 402 is on. As shown in 41, button 401 can be in the "on" state. The user can enter operation 403 to instruct the UE to turn off the 5G network. The operation 403 may include clicking button 401. In response to the operation 403, the UE can execute a change in the current 5G network state. For example, change the 5G network state from the "on" state to the "off" state. Correspondingly, the UE can display the latest state as "off" on button 401. In this way, after the user enters the operation 403, the UE can trigger the following operation: Figure 3 S303-S304 shown, try to access the 4G network to continue communication. In this application, the operation 403 may also be referred to as the first operation. Correspondingly, the first operation may be used to instruct the UE to enable 5G communication capability.

[0170] Based on this Figure 4 The logic shown in 42 can realize the opening of 5G network.

[0171] Take the example that the current 5G network switch in interface 402 is in the off state. As shown in 42, button 401 can be in the "off" state. The user can enter operation 404 to instruct the UE to turn on the 5G network. The operation 404 may include clicking button 401. In response to the operation 404, the UE can execute a change in the current 5G network state. For example, change the 5G network state from the "off" state to the "on" state. Correspondingly, the UE can display the latest state as "on" on button 401. In this way, after the user enters the operation 404, the UE can trigger the following operation: Figure 3 S305-S306 shown, try to access the 5G network to continue communication. In this application, the operation 404 may also be referred to as the second operation. Correspondingly, the second operation may be used to instruct the UE to enable 5G communication capability.

[0172] Thus, based on Figure 3The solution shown is implemented, and the UE can implement multiple changes of residence process from 5G to 4G to 5G. Among them, as shown in S306, after the UE changes to reside in the 5G network again, the registration request 35 sent to the network device will carry a TAU request in accordance with the protocol. As a result, after completing the registration with the 5G network shown in S306, the UE can communicate on the 5G network to implement voice calls, text messages and other services based on the 5G network.

[0173] It is understandable that after the network side (such as the 5G core network device) receives the registration request 35, it may be necessary to perform some synchronization through the TAU request in the registration request 35 (for example, obtain the UE's context information from the MME entity of the 4G network indicated by the TAU request), so as to provide the UE with the function of receiving a voice call or receiving a text message through the current 5G network based on the synchronization between the network side and the UE. Therefore, in this scenario, when the registration request sent by the UE to the 5G network device is of the MRU type, it is necessary to carry the TAU request.

[0174] In the actual existing network environment, during the change of UE's residence from 4G to 5G, the registration request 35 sent by the UE to the network device may not carry a TAU request. In this way, the network side cannot synchronize with the UE according to the TAU request, which leads to the problem that the UE cannot be called for a long time or cannot receive text messages.

[0175] Exemplary, reference Figure 5 Example. Figure 3 In comparison, S304 can be replaced by S501.

[0176] That is, Figure 5 In the scenario shown, after the UE executes S303 and achieves 4G RRC access to the eNB, S501 may be executed.

[0177] In S501, the UE may send a TAU request 33 to the eNB. The eNB may send the TAU request 33 to the corresponding 4G core network device.

[0178] In this Figure 5 In the example of FIG. 1 , the UE receives an operation (such as a command from a user to turn on the 5G network) before receiving the TAU acceptance message 34. Figure 4 Operation 404 shown), or, receiving a network change indication B sent from the currently resident eNB, or, the UE actively initiates network reselection to the 5G network, or the UE actively shuts down the 5G network.

[0179] In this way, the UE will execute the change of residence to the 5G network before receiving the TAU acceptance message 34.

[0180] For example, before receiving the TAU acceptance message 34, the UE initiates access to the 5G network to the gNB, and then initiates MRU type registration to the 5G core network through the gNB.

[0181] Therefore, even if the 4G core network device sends a TAU acceptance message 34 to the eNB, the UE may not be able to successfully receive (e.g., not receive in the 4G network in the future) the TAU acceptance message 34 due to the rapid switching of the standard and frequency (because the user performs operation 404 soon after performing operation 403). This also causes the TAU process corresponding to the UE performing process S501 to be incomplete.

[0182] In combination with the aforementioned provisions of Section 5.5.1.3 of 3GPP 24.501, when the UE initiates registration with the network device again (such as registering with the 5G network again), one of the conditions for carrying a TAU request in the registration request is that the UE in single registration mode performs an inter-system change from S1 mode to N1 mode.

[0183] However, in Figure 5 In the scenario shown, since the TAU process corresponding to the UE's execution of process S501 is not completed, the UE has not completed the inter-system change from S1 mode to N1 mode. Therefore, when the UE registers with the 5G network again and executes the process S502, the registration request 51 sent by the UE will not carry the TAU request. As a result, the 5G network equipment will not synchronize with the UE based on the TAU request. This will result in that even if the UE successfully registers with the 5G network, it will not be able to receive voice calls or text messages through the 5G network.

[0184] It is understandable that Figure 5 In the scenario shown, after the UE sends the TAU request 33, before the network replies with a TAU accept message to the UE, the network and the UE may need to execute processes such as SecurityModeCommand (security mode command), and the execution of these processes takes some time. In this way, if the user turns on the 5G switch on the UE before the UE can receive the TAU accept message replied by the LTE network, the UE will fail to receive the TAUaccept message replied by the LTE network. Accordingly, the UE's AP will send an indication message to the modem to indicate that the UE supports 5G. After receiving the indication message from the AP, the modem will search for NR cells and reside in an NR cell, and then initiate a registration (REGISTRATION) process to the NR cell.

[0185] Since the UE has not received the TAU accept message from the LTE network, the UE side will think that the previous TAU process is not completed, so the UE does not think that it is now performing an inter-system change from S1 mode to N1 mode. Therefore, the UE will not carry a TAU request (TAU request, also abbreviated as TAU req) in the REGISTRATION REQUEST message used to initiate the registration process to the NR cell. The network side (NR network in this case) may need to do some synchronization through the TAU req in the registration request REGISTRATION REQUEST. Since the UE does not carry TAUreq in the registration request (such as an MRU type registration request), the synchronization between the UE and the network side cannot be carried out, which leads to the problem that after the UE registration is completed, the UE (such as a mobile phone) cannot be called for a long time or cannot receive text messages, and the user experience is very poor.

[0186] It can be understood that the root cause of the call failure is that when the UE changes to reside in the 5G network again, the REGISTRATION REQUEST message sent by the UE to the network side does not carry a TAU request message, and the reason for not carrying the TAU request message is that the UE believes that it is not executing the inter-system change from S1 mode to N1 mode, that is, the terminal believes that condition 1 is not met. And the reason why the UE believes that the inter-system change from S1 mode to N1 mode is not executed is that the TAU process has not been completed (no TAU accept message has been received). Therefore, in the technical solution provided in the embodiment of the present application, one way for the terminal to believe that condition 1 is met is that the UE waits for the TAU process in the LTE network to be completed before returning to the NR network. Another way is that if the UE has successfully sent a TAU request, as long as the UE has not received a TAU reject message, it can be considered that the UE has resided in the LTE network. In this case, when the UE returns to the NR network, the UE can believe that the conditions for the inter-system change from S1 mode to N1 mode are met. When condition 1 is met, if conditions 2 and 3 are also met, that is, (2) if the registration process is started in 5GMM-IDLE mode; 3) the UE has received an indication from the network that it supports the N26 interface; then the UE should piggyback a TAU request message in the REGISTRATION REQUEST message.

[0187] In this way, after the UE changes to reside on the 5G network again, it can receive voice calls or text messages normally based on the 5G network.

[0188] refer to Figure 6 , is a schematic diagram of an interactive flow of a communication method provided in an embodiment of the present application. Figure 6 As shown, the program may include:

[0189] S601. UE and gNB perform 5G RRC access.

[0190] The execution steps of S601 can refer to Figure 3 S301 shown.

[0191] For example, the UE may implement 5G RRC access to the gNB by initiating a random access procedure to the gNB.

[0192] S602. The UE registers to the 5G network through the gNB.

[0193] The execution steps of S602 may refer to Figure 3 S302 shown.

[0194] Exemplarily, this step may specifically include:

[0195] 1) The UE sends a registration request 61 to the gNB, and the gNB sends a registration request 61 to the core network device. The registration request 61 may include a Registration Request message. In some implementations, the registration request 61 may carry a 5GS registration type value. For example, the 5GS registration type value carried by the registration request 61 may be 001, corresponding to performing an initial registration.

[0196] For the sake of convenience, in this application, a registration request carrying a 5GS registration type value indicates that an initial registration is performed, which can be referred to as a registration request of an initial registration type. The corresponding registration process can be referred to as a registration process of an initial registration type.

[0197] In contrast, a registration request carrying a 5GS registration type value indicates that an MRU registration request is executed, which can be referred to as an MRU type registration request. The corresponding registration process can be referred to as an MRU type registration process.

[0198] 2) The UE receives a registration accept message 62 from the gNB. For example, the registration accept message 62 may include a Registration Accept message.

[0199] In some implementations, the registration accept message 62 carries an indication that the N26 interface is supported.

[0200] In some implementations, after receiving the registration acceptance message 62, the UE may also send a Registration Complete message to the 5G network device.

[0201] In this way, the UE can communicate through the 5G network. For example, the UE can act as a called device and can normally receive voice calls or text messages on the 5G network.

[0202] S603. UE receives the user's operation of shutting down the 5G network.

[0203] Exemplarily, the operation of shutting down the 5G network may correspond to the following: Figure 4 Operation 403 is shown.

[0204] In combination with the aforementioned description about the terminal device (ie, UE), in this example, the UE may be configured with an AP and an MD.

[0205] In this way, the AP may receive the operation 403 input by the user. Correspondingly, the AP may generate a message to remove the NR. The AP may send the message to remove the NR to the MD of the UE for corresponding processing. In some embodiments, the message to remove the NR may also be referred to as a first instruction.

[0206] Correspondingly, the MD may trigger the UE to remove the NR capability according to the message of removing the NR, that is, trigger the UE's 5G communication capability to be disabled. For example, after receiving the message of removing the NR, the MD may trigger access to the 4G network. In this way, the UE may execute S604 accordingly.

[0207] It should be noted that, referring to the description in S302, the user's operation of shutting down the 5G network in S603 may be one of the multiple possible situations in which the UE's 5G communication capability is shut down / disabled. In other embodiments of the present application, the UE's 5G communication capability may be shut down / disabled, or the UE may automatically disable the 5G communication capability without user participation. When the UE's 5G communication capability is shut down / disabled (or it may also be stated that the UE is disabling the UE's 5G communication capability), the UE may execute the following S604.

[0208] In other embodiments of the present application, when the UE's 5G communication capability remains unchanged, the UE may also attempt to access other networks (such as 4G networks) to continue to provide communication services to users. For example, the UE may attempt to access the 4G network through the network reselection process. Figure 6 As shown, the UE changes to reside in another network (such as a 4G network) according to a network change indication A sent by a network device (such as a currently connected gNB). The network change indication A may include: a network redirection indication A1, or a network switching indication A2.

[0209] The network redirection indication A1 may include an RRCConnectionRelease message carrying a redirectedCarrierInfo indication. The redirectedCarrierInfo indication of the network redirection indication A1 may include the standard identifier (or system identifier) ​​of the 4G network to which the UE is redirected by the 5G network device of the currently resident 5G network, as well as the frequency.

[0210] The network switching indication A2 may include a Handover message. The Handover message of the network switching indication A2 may include the standard identifier (or system identifier) ​​of the 4G network to which the 5G network device indicates the UE needs to switch, as well as the frequency.

[0211] In the following description, it is taken as an example that the UE turns off / disables the 5G communication capability based on receiving the user's operation of turning off the 5G network shown in S603, and then executes the following S604.

[0212] S604: The MD of the UE performs 4G RRC access with the eNB.

[0213] The execution steps of S604 can refer to Figure 3 S303 shown.

[0214] Exemplarily, the MD of the UE may implement the 4G RRC access by initiating random access to the eNB of the 4G network.

[0215] In some embodiments, the UE may disconnect the RRC connection with the gNB before executing S604.

[0216] S605. The MD of the UE sends a TAU request 63 to the 4G network device.

[0217] The execution steps of S605 may refer to the relevant description in S304. The TAU request 63 may correspond to Figure 3 The TAU request 33 is shown. In this example, the TAU request 63 may include a TAU Request message.

[0218] It should be noted that, in some embodiments of the present application, a field corresponding to the TAU status may be configured in the MD of the UE.

[0219] When the field corresponding to the TAU status is configured with different values, it can respectively indicate that TAU ​​is not registered, TAU is registering, TAU registration is successful, and TAU registration fails.

[0220] After sending the TAU request 63 to the 4G network device, the UE configures the TAU state as TAU registering.

[0221] S606. The AP of the UE receives the user's operation of opening the 5G network.

[0222] Among them, the user's operation of opening the 5G network may correspond to the following Figure 4 Operation 404 is shown.

[0223] In this way, the AP can receive the operation 404 input by the user. Correspondingly, the AP can generate a message to increase the NR. The AP can send the message to increase the NR to the MD of the UE for corresponding processing. In some embodiments, the message to increase the NR can also be referred to as a second instruction.

[0224] Correspondingly, the MD may access the 5G network according to the message of adding the NR. In this way, the UE may execute S607 accordingly.

[0225] It should be noted that, referring to the description in S304, the user's operation of turning on the 5G network in S606 may be one of the multiple possible situations in which the UE's 5G communication capability is turned on / enabled. In other embodiments of the present application, the UE's 5G communication capability may be turned on / enabled in the absence of user participation, and the UE automatically enables the 5G communication capability. When the UE's 5G communication capability is turned on / enabled (or it may be stated that the UE is executing to enable the UE's 5G communication capability), the UE may execute the following S607.

[0226] In other embodiments of the present application, if the UE's 5G communication capability does not change, the UE may also attempt to access other networks (such as 5G networks) to continue to provide communication services to users. For example, the UE may attempt to access the 5G network through the network reselection process. Figure 6 As shown, the UE changes to reside in another network (such as a 5G network) according to a network change indication B sent by a network device (such as a currently connected gNB). The network change indication B may include a network redirection indication B1.

[0227] The network redirection indication B1 may include an RRCConnectionRelease message. The RRCConnectionRelease message of the network redirection indication B1 may carry a redirectedCarrierInfo indication. The redirectedCarrierInfo indication may include the standard identifier (or system identifier) ​​of the 5G network to which the UE is redirected by the 4G network device, as well as the frequency.

[0228] Compared with the aforementioned network change indication A, the network change indication B may not include a network switching indication.

[0229] It should be noted that, in this example, the UE may execute S607 accordingly after executing S605 and before receiving a corresponding response (such as a TAU acceptance message carrying a TAU Accept message, or a TAU rejection indication carrying a TAU Reject message). That is, the UE may execute S607 accordingly when the TAU status is TAU registering.

[0230] Therefore, when the UE reselects to NR, or the UE redirects from LTE to NR, or the UE switches from LTE to NR, or the UE is executing the 5G communication capability enabled by the UE, the modem will search for the NR cell and reside in an NR cell, and initiate the RRC access process and the registration process to the NR cell.

[0231] S607. The MD of the UE performs 5G RRC access with the gNB.

[0232] The execution steps of S607 may refer to the following Figure 3 S305 shown.

[0233] For example, the UE may initiate a random access procedure to the gNB, and upon completing the random access, implement RRC access to the 5G network.

[0234] S608: The MD of the UE determines that the TAU is not completed.

[0235] In an embodiment of the present application, the UE executes S608 before initiating registration with the 5G core network device.

[0236] Exemplarily, in some embodiments, TAU incompleteness can be understood as TAU process in progress.

[0237] For example, the MD of the UE may determine that the TAU is not completed based on having sent a TAU request (such as TAU request 63) but not receiving a corresponding TAU Accept message.

[0238] For another example, the MD of the UE may determine that the TAU is not completed based on having sent a TAU request (such as TAU request 63) but not receiving a corresponding TAU Accept message or TAU Reject message.

[0239] For another example, the MD of the UE may query the TAU status field, and when the TAU status field indicates that the TAU is being registered, it is determined that the TAU is not completed.

[0240] In this example, the UE may execute the following S609 when determining that the TAU is not completed.

[0241] In some other embodiments, the UE may also make a judgment based on the above condition 2 and / or condition 3. The UE may perform the following S609 when the TAU is not completed and condition 2 is met. Alternatively, the UE may perform the following S609 when the TAU is not completed and both condition 2 and condition 3 are met.

[0242] As described above, condition 2 may include: the UE's registration to the 5G network is performed in 5G MM-IDLE mode.

[0243] Condition 3 may include: the UE has received an indication from the network indicating that the network side supports the N26 interface.

[0244] Take the MD's judgment on whether condition 2 is satisfied as an example.

[0245] In some embodiments, the MD may determine that before triggering the execution of S607, if a user's operation of opening the 5G network is received, or a network redirection instruction is received, or a network reselection is performed, then the compliance judgment of condition 2 is passed / successful. Conversely, if the above conditions are not met, the compliance judgment of condition 2 is not passed / failed. For example, the MD may determine that before triggering the execution of S607, a network switching instruction is received, then the compliance judgment of condition 2 is not passed / failed.

[0246] In other embodiments, take the case where a field identifier of the 5GMM state is configured in the AP or MD of the UE. When the field of the 5GMM state is configured with different values, it can correspond to indicating that the UE is in the 5GMM-IDLE state, or the UE is in the 5GMM-Active state. In this way, the MD can query the field identifier of the 5GMM state. When the field identifier of the 5GMM state indicates that the UE is in the 5GMM-IDLE state, the compliance judgment of the condition 2 passes / succeeds. On the contrary, when the field identifier of the 5GMM state indicates that the UE is in other states other than the 5GMM-IDLE state (such as the 5GMM-Active state), the compliance judgment of the condition 2 does not pass / fail.

[0247] Take the MD's judgment on whether condition 3 is satisfied as an example.

[0248] The MD can query whether it has received an indication of supporting the N26 interface from the network device of the 5G network to be accessed. If the UE has been resident on the 5G network and has received an indication of supporting the N26 interface from the 5G network device, the compliance judgment of condition 3 is passed / successful. Otherwise, the compliance judgment of condition 3 is not passed / failed.

[0249] It should be noted that, in the specific implementation process, the order in which the MD executes the judgment of whether the above conditions are met is not limited. The specific execution can be parallel or serial. This embodiment of the application does not limit this.

[0250] In some implementations, the “TAU incomplete” may also correspond to satisfying a preset condition configured in the MD.

[0251] Exemplarily, in some embodiments of the present application, the MD of the UE determines that the TAU is not completed, and other conditions are met, which may correspond to: before the UE sends a registration request (such as a subsequent registration request 64) to the first NR cell, the TAU process is in progress. Among them, the TAU process can be a TAU process to the 4G network. For example, the TAU process can be initiated by sending a TAU request 63 in S605. Correspondingly, after the UE sends the TAU request 63, receiving a TAU Accept message corresponds to the successful completion of the TAU process; receiving a TAU Reject message corresponds to the failure of the TAU process; and not receiving a TAU Accept message or a TAU Reject message corresponds to the TAU process being in progress.

[0252] S609. The MD of the UE sends a registration request 64 to the 5G network device.

[0253] Exemplarily, the UE may send a registration request 64 to the gNB. Correspondingly, the gNB may transparently transmit the registration request 64 to the 5G core network device. In some embodiments, the registration request 64 may also be referred to as a first registration request.

[0254] In this example, the registration request 64 may include a Registration Request message. In addition, the 5GS registration type value carried by the registration request 64 may be 001, corresponding to a request to perform an initial registration.

[0255] S610 , the MD of the UE receives the registration acceptance message 65 .

[0256] Exemplarily, the registration acceptance message 65 may include a Registration Accept message. In some implementations, after receiving the registration acceptance message 65, the UE may also send a Registration Complete message to the 5G network device.

[0257] It can be understood that if the UE's modem successfully sends a TAU request in LTE and before sending a REGISTRATION REQUEST message for initiating the above-mentioned registration process to the NR cell (such as when the modem is preparing to send the REGISTRATION REQUEST message to the NR cell, or when the modem receives the second instruction, etc.), the TAU process has not been completed (the TAU process has not been completed, which can be understood as the TAU process is still in progress, such as after the modem sends the TAU request, it has not received a TAU reject message sent by the LTE network, nor has it received a TAU accept message sent by the LTE network), in this case, according to the protocol, the UE's modem will send a registration request to the NR cell, and carry indication information for indicating that the registration type is a mobile registration update (Mobility Registration Updating, MRU) in the registration request, and the registration request will not carry TAU req. In this embodiment, in this case, the UE's modem can send a registration request to the NR cell, and carry an indication information for indicating that the registration type is an initial registration (initial) in the registration request. In this way, the UE initiates initial registration with the NR cell. After the initial registration is completed (such as the UE receives the registration accept message replied by the NR cell), the UE and the NR cell are synchronized. In this case, if other users call the UE, the UE can receive the call normally as the called party.

[0258] In other words, in Figure 3 In the example, when the UE receives the TAU Accept message, the 5GS registration type value that the registration request 35 can carry can be 010, corresponding to a request to perform a mobility registration update.

[0259] In this Figure 6 In the example of FIG. 1 , when the UE determines in S608 that the TAU is not completed, the UE may initiate a registration process of the initial registration type (such as the UE sending a registration request 64 of the initial registration type in S609), instead of following the procedure described above. Figure 5 The mobility registration update process shown in FIG. 5 is performed (e.g., the UE sends a registration request 51 without a TAU request in S502). This avoids the following Figure 5The 5G network device shown in the figure fails to synchronize with the UE due to the lack of a TAU request in the registration request during the mobility registration update process. Correspondingly, through the initial registration process, the network can re-synchronize the information with the UE, so that the UE can be called or receive text messages normally after successfully registering on the 5G network through S609-S610.

[0260] It should be noted that in the embodiment of the present application, when the TAU process of the 4G network is completed (such as receiving the TAU Accept message corresponding to the TAU request 63), the UE can change the residence to the 5G network in the process of changing the residence to the 5G network. Figure 3 As shown in S306, a registration request of the MRU type is sent to the 5G network device to request the 5G network to perform a mobility registration update.

[0261] refer to Figure 7 , is a schematic diagram of an interaction flow of another communication method provided in an embodiment of the present application. Figure 6 Description of the program, such as Figure 7 As shown, the solution may also include S601-S607. The implementation of each step may refer to Figure 7 The instructions in the article are not repeated here.

[0262] In such Figure 7 In the implementation of the solution, the UE executes S607, and after successfully accessing the NR cell, it can execute S701-S703.

[0263] S701. The MD of the UE determines that the TAU is not completed and other conditions are met. Exemplarily, in this example, in addition to determining that the TAU is not completed, the UE may also determine that other conditions (such as condition 2, or condition 2 and condition 3) are met. For specific implementation, refer to the relevant description in S608, which will not be repeated here.

[0264] S702. The MD of the UE sends a registration request 71 to the 5G network device.

[0265] The registration request may include a Registration Request message. In some embodiments of the present application, the registration request 71 may also be referred to as a second registration request.

[0266] The registration request 71 carries a TAU request. The TAU request may include Figure 6 or Figure 7 At least part of the information in the TAU request 63 of S605. For example, the TAU request carried by the registration request 71 may include relevant information of the MME entity corresponding to the 4G network when the UE registers with the 4G network device.

[0267] As a specific implementation manner, the MD may carry the Eps_nas_msg_container field in the sent registration request 71. The Eps_nas_msg_container may include Eps_nas_msg[]=72. The message of Eps_nas_msg[]=72 corresponds to the TAU request message.

[0268] In this Figure 7 In the example, there is no restriction on the type of registration request 71.

[0269] Exemplarily, in some embodiments, the 5GS registration type value carried in the registration request 71 may be 001, corresponding to a request to perform an initial registration. In other embodiments, the 5GS registration type value carried in the registration request 71 may be 010, corresponding to a request to perform a mobility registration update.

[0270] S703 , the MD of the UE receives the registration acceptance message 72 .

[0271] Exemplarily, the registration acceptance message 72 may include a Registration Accept message. In some implementations, after receiving the registration acceptance message 72, the UE may also send a Registration Complete message to the 5G network device.

[0272] It is understandable that in this Figure 7 In the implementation of the provided solution, if the modem has successfully sent a TAU request in LTE when the modem receives the second instruction, and the modem has not received a TAU reject message since the modem sent the TAU request until the modem received the second instruction, it can be considered that the UE has already resided in the LTE network. In this case, the modem returns to the NR network in response to receiving the second instruction, and it can be considered that the UE meets the conditions for the inter-system change from S1 mode to N1 mode. The above-mentioned registration process for MRU initiated to the NR cell occurs in the scenario where the user turns on the 5G switch. It can be seen that the registration process is initiated in 5GMM-IDLE mode. Furthermore, as long as the UE has previously received indication information from the network indicating support for the N26 interface, the UE's modem can carry a TAU request message in the REGISTRATION REQUEST message sent to the NR cell to initiate the above-mentioned registration process.

[0273] Thus, through Figure 6 as well as Figure 7The provided solution implements that if the UE has successfully sent a TAU request, as long as the UE has not received a TAU reject message, it can be considered that the UE has resided in the LTE network. In this case, the UE returns to the 5G network, and the UE can be considered to have met the conditions for the inter-system change from S1 mode to N1 mode. When condition 1 is met, if conditions 2 and 3 are also met, the UE can initiate a registration process of the initial registration type, or initiate an MRU type registration process, in order to send a registration request carrying a TAU request, so that the network side can synchronize with the UE based on the initial registration or the TAU request in the registration request. This ensures that after the UE changes to reside in the 5G network, it can receive voice calls or text messages from the 5G network.

[0274] In some other embodiments of the present application, the UE may also wait for a period of time after camping on the LTE network and before initiating registration with the 5G network. Thus, during the waiting time, after the UE receives a TAU acceptance message (such as a TAU Accept message), it initiates registration with the 5G network. In this way, according to the protocol, conditions 1 to 3 can be met, so that the UE can register with the 5G network as shown in the following example. Figure 3 The solution shown is implemented to normally reside in the 5G network and be able to make voice calls or receive text messages through the 5G network.

[0275] As a specific example, see Figure 8 , is a schematic diagram of an interaction flow of another communication method provided in an embodiment of the present application. Figure 8 As shown, the program may include:

[0276] S801. The MD of the UE performs 5G RRC access with the gNB.

[0277] The execution steps of S801 can refer to Figure 6 or Figure 7 S601 shown.

[0278] For example, the MD of the UE can implement 5G RRC access to the gNB by initiating a random access procedure to the gNB.

[0279] S802. The MD of the UE registers with the 5G network through the gNB.

[0280] The execution steps of S802 may refer to Figure 6 S602 shown.

[0281] Exemplarily, this step may specifically include:

[0282] 1) The UE sends a registration request 81 to the gNB, and the gNB sends a registration request 81 to the core network device. The registration request 81 may include a Registration Request message. In some implementations, the registration request 81 may carry a 5GS registration type value. For example, the 5GS registration type value carried by the registration request 81 may be 001, corresponding to performing an initial registration.

[0283] 2) The UE receives a registration accept message 82 from the gNB. For example, the registration accept message 82 may include a Registration Accept message. In some implementations, the registration accept message 82 carries an indication of supporting the N26 interface.

[0284] In some implementations, after receiving the registration acceptance message 82, the UE may also send a Registration Complete message to the 5G network device.

[0285] In this way, the UE can communicate through the 5G network. For example, the UE can act as a called device and can normally receive voice calls or text messages.

[0286] S803. The AP of the UE receives the user's operation of shutting down the 5G network.

[0287] The execution of step S803 may refer to Figure 6 S603 shown.

[0288] Exemplarily, the operation of shutting down the 5G network may correspond to: Figure 4 Operation 403 is shown.

[0289] In this embodiment, after receiving the user's operation of shutting down the 5G network, the AP of the UE may trigger the execution of the following S804 and S805. In different implementations, the execution order of S804 and S805 may not be limited.

[0290] S804, the AP of the UE starts a timer T1. During the timer T1, the 5G switch is inoperable.

[0291] Exemplarily, in some embodiments, the AP of the UE may trigger the start timer T1 after receiving the user's operation of shutting down the 5G network. In other embodiments, the AP of the UE may trigger the start timer T1 after sending a message to remove the NR to the MD. In other implementations, the timer T1 may also be referred to as the first timer.

[0292] The timer T1 corresponds to the configured timing duration 1. For example, the timing duration 1 may be less than or equal to 5 seconds. In other implementations, the timing duration 1 may also be referred to as the first duration.

[0293] It is understandable that, in this example, the timer T1 may be configured in the AP. Thus, based on the configuration of the timer T1, the coupling of the corresponding function in the AP can be achieved.

[0294] Combination Figure 4 In the present application, the AP can be used to control the interface display of the UE and accept the operation input by the user. The AP can also send corresponding instructions to the MD according to the operation input by the user.

[0295] In this example, after the timer T1 is started, the AP can configure the 5G switch button displayed by the UE to be inoperable before the timer T1 expires. For example, the 5G switch button can be as follows: Figure 4 The configuration of the 5G switch button being inoperable may include: not responding when receiving an operation of the 5G switch button by the user. In some implementations, when the AP configures the 5G switch button to be inoperable, the button 401 on the control interface may also be displayed as inoperable.

[0296] In this way, after the UE receives the user's operation 403 on the interface 402, the 5G network enable switch will not be turned on before the timer T1 expires.

[0297] Therefore, time (such as the timing duration 1 corresponding to timer T1) can be reserved for the UE to receive the TAU Accept message before initiating the registration of the 5G network, thereby increasing the probability of the UE receiving the TAU Accept message before initiating the registration of the 5G network.

[0298] S805. The AP of the UE sends a message to remove the NR to the MD of the UE.

[0299] As shown in S803, the AP of the UE may receive operation 403 input by the user. Correspondingly, the AP may generate a message to remove the NR. The AP may send the message to remove the NR to the MD of the UE for corresponding processing. The MD may trigger the UEremove NR capability according to the message to remove the NR, which may be understood as the UE disabling the 5G communication capability.

[0300] In some implementations, after receiving the message to remove the NR, the MD may search for and access a nearby network, for example, a 4G network. In this way, the UE may execute S806 accordingly.

[0301] It should be noted that in some other embodiments of the present application, the UE may also actively disable the 5G communication capability based on network reselection to the 4G network, or after receiving a network change indication A, or for other reasons, and execute S806 accordingly.

[0302] The network change indication A may include a network redirection indication A1 or a network switching indication A2. Figure 6 The instructions in the article are not repeated here.

[0303] S806. The MD of the UE performs 4G RRC access with the eNB.

[0304] The execution steps of S806 may refer to the following Figure 6 S604 shown.

[0305] Exemplarily, the MD of the UE may implement the 4G RRC access by initiating random access to the eNB of the 4G network.

[0306] In some embodiments, the UE may disconnect the RRC connection with the gNB before executing S806.

[0307] S807 , the MD of the UE sends a TAU request 83 to the 4G network device, and the MD of the UE receives a TAU acceptance message 84 .

[0308] Exemplarily, the MD of the UE may initiate a TAU process to the 4G network device after completing RRC access to the eNB.

[0309] As an example, the execution process of S807 may correspond to the following: Figure 3 S304 shown in FIG. 8 . The TAU request 83 may correspond to Figure 3 The TAU request 33 shown in FIG. 8 may include a TAU Request message. The TAU acceptance message 84 may correspond to the following: Figure 3 The TAU accept message 34 is shown, and the TAU accept message 84 may include a TAU Accept message.

[0310] It can be understood that, in some embodiments, the MD of the UE in S807 may receive the TAU acceptance message 84 during the timing of the timer T1.

[0311] In some embodiments, the MD of the UE may send a TAUcomplete message to the 4G network device after receiving the TAU accept message 84 .

[0312] S808. The MD of the UE sends a TAU acceptance message 84 to the AP, so that the AP can know that the current TAU ​​process has been successful.

[0313] S809 . When timer T1 times out or a TAU acceptance message is received, the AP of the UE terminates timer T1 .

[0314] It can be understood that after timer T1 expires, the corresponding AP can control the 5G switch button displayed on the UE to be operational.

[0315] In this application, the exit mechanism of timer T1 can be configured to meet any of the following conditions:

[0316] The AP receives the TAU acceptance message sent by the MD, or the timing duration of the timer T1 expires.

[0317] Take the case where the AP receives a TAU acceptance message sent by the MD and terminates timer T1 as an example. It can be understood that the TAU process has been successful when the timer T1 has not expired. There is no need to wait for the timer T1 to expire, the UE can receive the user input to open the 5G network, and then re-resident on the 5G network. Since the TAU process has been successful, when registering with the 5G network device in the process of re-resident on the 5G network, the TAU request can be carried in the registration request in accordance with the protocol to achieve synchronization between the network side and the UE. In other embodiments, the AP receiving the TAU acceptance message sent by the MD can also be replaced by the AP knowing that the MD has sent a TAU complete message.

[0318] Take the case where timer T1 expires and timer T1 is terminated as an example. In this way, no TAU Accept message has been received during the timing of timer T1. This may be due to a failure on the 4G network side or other reasons that cause the UE to be unable to successfully reside on the 4G network. In this way, the AP can also terminate timer T1 and no longer wait for the TAU Accept message. This prevents the UE from setting the 5G network switch to inoperable for too long, preventing users from mistakenly believing that the 5G network switch has failed.

[0319] In this example, as shown in S808-S809, it is taken that when the AP receives a TAU acceptance message (such as TAU acceptance message 84), that is, when the TAU process is successful, the timer T1 is terminated.

[0320] S810. The AP of the UE receives the user's operation of turning on the 5G network, and the AP generates a message of adding NR and sends it to the MD.

[0321] The execution steps of S810 may refer to the following Figure 6 S606 shown.

[0322] It is understandable that, since the timer T1 has expired in S809, the 5G network switch is restored to an operable state. Correspondingly, the user can instruct the UE to turn on the 5G network by inputting operation 404. Correspondingly, the AP of the UE can generate a message to increase the NR. The AP can send the message to increase the NR to the MD of the UE for corresponding processing.

[0323] It should be noted that in this example, the UE receives an operation from a user to turn on the 5G network, triggering the UE to re-camp on the 5G network. Figure 6 The solution in the description is that the UE may also actively enable the 5G communication capability based on network reselection to the 5G network or other reasons, or trigger the UE to re-reside on the 5G network based on receiving a network change indication B.

[0324] Correspondingly, the function of timer T1 can also be adjusted as follows: during the timing of timer T1, the UE does not send a registration request to the 5G network. If during the timing of timer T1, the MD determines to reselect the network, or receives a network change indication B sent by the 4G network device, the information corresponding to the network reselection or network change indication B is cached. After timer T1 expires, a response to the cached information is executed, such as initiating registration with the 5G network.

[0325] S811. UE's MD performs 5G RRC access with gNB.

[0326] The execution steps of S811 can refer to the following Figure 6 S607 shown.

[0327] For example, the UE may initiate a random access procedure to the gNB, and upon completing the random access, implement RRC access to the 5G network.

[0328] S812. The MD of the UE sends a registration request 85 to the gNB. The gNB sends the registration request 85 to the core network device.

[0329] S813. UE receives the registration acceptance message 86 from gNB.

[0330] For example, the execution process of S812-S813 can refer to Figure 3 S306 shown. In some implementations, after receiving the registration acceptance message 86, the UE may also send a Registration Complete message to the 5G network device.

[0331] Among them, since the TAU registration on the 4G network is successful, therefore, when both conditions 2 and 3 are met, the registration request 85 can carry the TAU request information. Correspondingly, the 5G network device can synchronize with the UE according to the TAU request information to realize the normal call of the UE on the 5G network. In some embodiments, the registration request 85 can also be called a third registration request.

[0332] In some other embodiments of the present application, before timer T1 expires, the MD of the UE receives a TAU reject message. In this way, the MD can transmit the TAU reject message to the AP. Correspondingly, the AP can terminate timer T1. Thereafter, the MD of the UE can search for and reside in the NR cell. After successfully residing in the NR cell, the MD can initiate an MRU type registration request to the 5G network. Based on the existing protocol, the MRU type registration request may not carry a TAU request.

[0333] It is understandable that in this Figure 8 In the implementation of each solution provided, although not all cases can make the UE as the called party receive the call normally, in most cases it will be as follows Figure 8 The process shown is executed. In most cases, the UE as the called party can normally receive the call, thereby improving the probability that the UE as the called party can normally receive the call as a whole.

[0334] The Figure 8 In the implementation of the provided solution, a timer is configured in the AP to control whether the 5G network switch is operable. It can be understood that in this example Figure 8 The provided solution is effective and can be perceived by the user on the interface. For example, refer to Fig. 9 Before starting timer 1, the 5G network switch (such as button 401) on the UE is in an operable state. Figure 8 In the solution provided, when the 5G network switch is configured to be inoperable, the button 401 may also be displayed as an inoperable gray. Afterwards, when the timer 1 exits, the 5G network switch resumes to be operable, and the corresponding button 401 may also resume to be displayed as an operable state.

[0335] In some other embodiments of the present application, the timer may also be configured in the MD of the UE.

[0336] As an example, refer to Fig.10 , is a schematic diagram of an interaction flow of another communication method provided in an embodiment of the present application. Fig.10 As shown, the program may include:

[0337] S1001. UE's MD performs 5G RRC access with gNB.

[0338] The execution steps of S1001 can refer to Figure 8 S801 shown.

[0339] For example, the MD of the UE can implement 5G RRC access to the gNB by initiating a random access procedure to the gNB.

[0340] S1002. The MD of the UE registers with the 5G network through the gNB.

[0341] The execution steps of S1002 can refer to Figure 8 S802 shown.

[0342] S1003. The AP of the UE receives the user's operation of shutting down the 5G network.

[0343] The execution of step S1003 may refer to Figure 8 S803 shown.

[0344] S1004. The AP of the UE sends a message to remove the NR to the MD of the UE.

[0345] The execution of step S1004 may refer to Figure 8 S805 shown.

[0346] S1005. The MD of the UE performs 4G RRC access with the eNB.

[0347] The execution of step S1005 may refer to Figure 8 S806 shown.

[0348] S1006. The MD of the UE sends a TAU request 83 to the 4G network device.

[0349] The execution of step S1006 may refer to Figure 8 The corresponding description of S807 is shown.

[0350] S1007. The MD of the UE starts timer T2.

[0351] like Fig.10 The operation of starting the timer T2 by the MD of the UE may be triggered when the MD initiates a TAU process to the 4G network (such as executing S1006 to send a TAU request 83). In some embodiments, the MD may trigger the execution of S1007 according to the change in the value of the TAU status field, when the changed TAU status is TAU registering.

[0352] In this example, a timer T2 may be configured in the MD of the UE. During the timing of the timer T2, the UE temporarily does not perform the registration process with the 5G network.

[0353] In some cases, during the timing of the timer T2, the MD may also receive an instruction to change the residence. Correspondingly, the MD may process according to the following steps S1008-S1009.

[0354] S1008. The AP of the UE receives the user's operation of turning on the 5G network, and the AP generates a message of adding NR and sends it to the MD.

[0355] For example, during the timing of timer T2, the AP may receive an operation from the user to turn on the 5G network. For example, the operation may be as follows: Figure 4 Operation 404 is shown.

[0356] Correspondingly, the AP can generate a message to add NR and send it to the MD to instruct the MD to search for and reside on the 5G network.

[0357] S1009. The UE's MD cache changes the indication of residence.

[0358] In this example, the indication of changing the residence may include a message of adding an NR sent by the AP.

[0359] It is understandable that, since the timer T2 is timing, the MD may cache the received message of increasing the NR in a designated location, so as to respond to the cached message of increasing the NR after the timer T2 is exited.

[0360] In the above S1008-S1009, the indication of changing the residence includes a message of adding NR sent by the AP as an example. That is, in this example, the operation of opening the 5G network input by the user triggers the change of residence to the 5G network.

[0361] In some other embodiments, the indication of changing the residence may also include: information generated by the MD during the network reselection process; or a network change indication B received by the MD. The specific implementation of the network change indication B can refer to the above description and will not be repeated here.

[0362] Thus, when the MD receives any of the above-mentioned instructions for changing the residency during the timing of the timer T2, the MD can cache the instruction for changing the residency in a designated location, so as to respond to the cached instruction for changing the residency after the timer T2 is exited.

[0363] S1010 , the MD of the UE receives the TAU acceptance message 84 .

[0364] In this example, the UE may receive the TAU acceptance message 84 during the timing of the timer T2. Thus, based on the waiting of the timer T2, the UE may receive the TAU acceptance message 84 before initiating registration of the 5G network.

[0365] S1011a. When timer T2 times out or a TAU acceptance message is received, terminate timer T2.

[0366] The exit mechanism of the timer T2 is similar to the exit mechanism of the aforementioned timer T1. The specific implementations can be referenced to each other.

[0367] S1011b, after timer T2 exits, respond to the cached indication. For example, after timer T2 exits, the UE may respond to the information generated by the MD during the cached network reselection process; or the network change indication B received by the MD; or the message of adding NR. Correspondingly, the UE may execute the following S1012.

[0368] S1012. The MD of the UE performs 5G RRC access with the gNB.

[0369] S1013. The MD of the UE sends a registration request 85 to the gNB. The gNB sends the registration request 85 to the core network device.

[0370] S1014. UE receives the registration acceptance message 86 from gNB.

[0371] In this example, the execution process of S1012-S1014 can be referred to respectively. Figure 8 In S811-S813, the specific implementation can refer to each other and will not be repeated. In some implementations, the registration request 85 in S1013 can also be called the fourth registration request. In some implementations, the fourth registration request can be the same as the third registration request.

[0372] It should be noted that similar to Figure 8In the example, in other embodiments of the present application, if the UE's modem receives a TAU reject message before timer T2 times out, the UE may stop timer T2, and after T2 stops, the modem searches for the NR cell and resides, initiates the RRC access process and the MRU process, and does not carry a TAU request message in the REGISTRATION REQUEST message. In this case, after the UE successfully registers with the 5G network, the UE as the called party will experience a problem of being unable to be called. Or, in other embodiments of the present application, if the UE's modem does not receive a TAU reject message or a TAU accept message until timer T2 times out, then after timer T2 times out, the modem searches for the NR cell and resides, initiates the RRC access process and the MRU process, and does not carry a TAU request message in the REGISTRATION REQUEST message. In this case, after the UE successfully registers with the 5G network, the UE as the called party will experience a problem of being unable to be called. Although the above does not enable the UE as the called party to receive calls normally in all cases, in most cases it will be as follows. Fig.10 The process shown is executed. In most cases, the UE as the called party can normally receive the call, thereby improving the probability that the UE as the called party can normally receive the call as a whole.

[0373] So, how should Fig.10 In the implementation of the solution shown, timer T2 is configured in MD, and similar Fig. 9 In the scheme shown, before the UE initiates the registration for re-residence on the 5G network, it waits for the timer T2 to count down. This increases the probability that the TAU process on the 4G network is completed before the UE initiates the registration for re-residence on the 5G network. This increases the probability that the UE carries a TAU request in the registration request sent to the 5G network device, so that the network side can complete synchronization with the UE and provide normal call reception. In addition, the Fig.10 In the solution shown, since the timer T2 is configured in the MD, the interface information provided by the UE to the user is not affected. For example, the user will not see that the 5G switch is inoperable on the interface. This achieves that the user does not perceive the implementation of the solution.

[0374] It should be noted that, in the description of the implementation of the above-mentioned solutions, the various solutions provided in the embodiments of the present application are described by taking the case where the UE changes its residence from the 5G network to the 4G network and receives a TAU acceptance message on the 4G network before re-registering with the 5G network as an example.

[0375] In other embodiments, the various solutions provided in the embodiments of the present application can also be extended and applied to switching and residence scenarios between other standards (such as not limited to 4G and 5G, such as 5G and 6G, 6G and 7G, etc.).

[0376] For example, the UE resides in the first network. The UE changes to reside in the second network by disabling the communication capability of the first network or under the instruction of the first network device. Accordingly, the UE can reside in the cell of the second network. For example, the UE can initiate an RRC connection to the cell of the second network and then reside in the cell of the second network. Thereafter, the UE can also initiate a mobility location update process to the cell of the second network. For example, the UE can send a mobility location update request to the cell of the second network.

[0377] Corresponding to the above embodiment, when the first network is a 5G network and the second network is a 4G network, the mobility location update request sent by the UE to the cell of the second network may be a TAU request, and the corresponding mobility location update process in the 4G scenario may be referred to as a TAU process. In other embodiments, when the second network is a 5G network, the mobility location update request sent by the UE to the cell of the second network may be referred to as an MRU request (or an MRU type registration request), and the corresponding mobility location update process in the 5G scenario may be referred to as an MRU process.

[0378] Combination Figure 5 According to the description, after the UE initiates the mobility location update process to the cell of the second network and the mobility location update process is not completed, it can search for and access the cell of the first network by enabling the communication capability of the first network or receiving a message to re-reside on the first network. Then, the UE can also send a registration request to the core network device of the first network through the cell of the first network.

[0379] Based on the existing solution implementation, since the mobility location update process in the second network is not completed, the registration request sent to the core network device of the first network may not carry a mobility location update request. Taking the first network as a 5G network and the second network as a 4G network as an example, the registration request may be of MRU type, and the registration request not carrying a mobility location update request may correspond to: the registration request does not carry a TAU request. Taking the first network as a 6G network and the second network as a 5G network as an example, the registration request not carrying a mobility location update request may correspond to: the registration request does not carry an MRU request. This will cause the UE to be unable to receive voice calls or text messages normally on the first network.

[0380] Based on the solution provided in the embodiment of the present application, the UE can send a registration request of the initial registration type to the first network according to the ongoing mobility location update process; or, the UE can send a registration request carrying a mobility location update request to the first network according to the ongoing mobility location update process and when other conditions (such as condition 2, or condition 2 and condition 3) are met; or, the AP of the UE can start the first timer after receiving a message to disable the first network capability or to change the residency to the second network; or, the MD of the UE can start the second timer after sending a mobility location update request to the second network. This avoids the UE from being unable to receive voice calls or text messages normally after re-residing on the first network, and can increase the probability of the UE receiving voice calls or text messages normally after re-residing on the first network.

[0381] The above descriptions of the solutions provided in the embodiments of the present application are all described from the perspective of the UE or the AP or MD in the UE. Fig.11 , which is an example of the composition of the hardware structure of a terminal device (ie, UE) provided in an embodiment of the present application.

[0382] like Fig.11 As shown, the terminal device may include a processor, an external memory interface, an internal memory, a Universal Serial Bus (USB) interface, a charging management module, a power management module, a battery, an antenna 1, an antenna 2, a mobile communication module, a wireless communication module, a sensor module, a button, a motor, an indicator, a camera, a display screen, and a SIM card slot, etc. The audio module may include a speaker, a receiver, a microphone, an earphone interface, etc., and the sensor module may include a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, etc.

[0383] It is to be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the terminal device. In other embodiments, the terminal device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0384] The processor may include one or more processing units, for example, the processor may include an application processor (AP), a modem (also called a baseband processor), a graphics processor (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), and / or a neural-network processing unit (NPU). Different processing units may be independent devices or integrated into one or more processors. The processor is the nerve center and command center of the terminal device. The controller may generate an operation control signal according to the instruction opcode and timing signal to complete the control of fetching and executing instructions.

[0385] The wireless communication function of the terminal device can be implemented through antenna 1, antenna 2, mobile communication module, wireless communication module, and Modem, etc. In some embodiments, the antenna 1 of the terminal device is coupled with the mobile communication module, and the antenna 2 is coupled with the wireless communication module, so that the terminal device can communicate with the network side device and other terminal devices through wireless communication technology.

[0386] In addition, an operating system runs on the above components. Developed by the company operating system, Developed by the company Open source operating system, Developed by the company Operating system, etc.

[0387] The operating system of the terminal device can adopt a layered architecture, an event-driven architecture, a micro-kernel architecture, a micro-service architecture, or a cloud architecture. The system is used as an example to illustrate the hardware and software structure of the terminal device. The system is used as an example, but the basic principles are also applicable to or Terminal devices with other operating systems.

[0388] Exemplary, reference Fig.12 , is a software structure block diagram of a terminal device provided in an embodiment of the present application. The software structure adopts a layered architecture, which divides the software into several layers, each layer has a clear role and division of labor. The layers communicate with each other through software interfaces. system, Taking the system running on AP as an example, in some embodiments, the Android system is divided into five layers, from top to bottom, namely, application layer, application framework layer (Framework), Android runtime (Android runtime) and system library, hardware abstraction layer (HAL) and system kernel layer (Kernel).

[0389] Among them, the application layer may include a series of application packages. Application packages may include camera, gallery, calendar, call, map, WLAN, Bluetooth, music, video, short message and other APPs. The application layer may also include system UI (system UI). System UI is used to display the interface of the terminal device, such as displaying the signal icon corresponding to the SIM card, displaying the call interface, etc. The application framework layer provides an application programming interface (Application Programming Interface, API) and a programming framework for the applications in the application layer. The application framework layer includes some predefined functions. For example, the application framework layer may include a window manager, a content provider, a view system, a phone manager, a resource manager, a notification manager, etc. The phone manager is used to provide call functions for the terminal device, such as management of call status (including connecting, hanging up, etc.). The phone manager is in Fig.12 The application framework layer may also include a Radio Interface Layer (RIL), and a modem processor (Modem) may exchange information with the telephony through the RIL.

[0390] Modem may include NAS (Non-Access Stratum, non-access layer) layer, RRC (radio resource control, radio resource control) layer, Packet Data Convergence Protocol (Packet Data Convergence Protocol, PDCP) layer, Radio Link Control (Radio Link Control, RLC) layer, Medium Access Control Layer (Medium Access Control Layer, MAC) layer and Physical (Physical, PHY) layer. The aforementioned layers may be software modules. Modem may interact with base stations through antennas.

[0391] also, Fig.13As shown, a schematic diagram of the composition of a terminal device 1300 provided in some embodiments of the present application is provided. The terminal device 1300 includes: one or more processors 1301 and a memory 1302; the memory 1302 is used to store computer program codes, and the computer program codes include computer instructions. When the one or more processors 1301 execute the computer instructions, the terminal device executes the technical solution provided in any embodiment of the above description.

[0392] refer to Fig.14 , a schematic diagram of the composition of a chip system 1400 is provided for some embodiments of the present application. The chip system 1400 is applied to a terminal device, and the chip system 1400 includes at least one processor 1401 and a communication interface 1402. The communication interface 1402 is used to receive instructions and transmit them to at least one processor 1401; at least one processor 1401 executes the instructions so that the terminal device executes the above communication method. Among them, the chip system can be a modem, or a system on chip (System on Chip, Soc) including a modem, and the above method can be implemented by a modem.

[0393] In other embodiments of the present application, the chip system includes: a processing circuit, a receiving pin and a transmitting pin. The receiving pin, the transmitting pin and the processing circuit communicate with each other through an internal connection path, and the processing circuit executes the communication method provided in any of the above embodiments to control the receiving pin to receive a signal and control the transmitting pin to send a signal.

[0394] In addition, an embodiment of the present application provides a terminal device, which has the function of implementing the behavior of the terminal device in any of the above method embodiments. The function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to each sub-function in the above function. Specifically, the terminal device can be a user device, such as a mobile phone.

[0395] An embodiment of the present application also provides a communication system, which includes the network device and terminal device described in any of the above embodiments.

[0396] The present application also provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a computer, the method flow related to the terminal device in any of the above method embodiments is implemented. Specifically, the computer can be the above terminal device.

[0397] The present application also provides a computer program or a computer program product including the computer program, which, when executed on a computer, enables the computer to implement the method flow related to the terminal device in any of the above method embodiments. Specifically, the computer may be the above terminal device.

[0398] The present application also provides a computer program or a computer program product including the computer program, which, when executed on a computer, enables the computer to implement the method flow related to the network device in any of the above method embodiments. Specifically, the computer may be the above network device.

[0399] The embodiment of the present application also provides a device, which is applied to a terminal device, and the device is coupled to a memory, and is used to read and execute instructions stored in the memory, so that the terminal device can execute the method flow related to the terminal device in any of the above method embodiments. The memory can be integrated in the processor or independent of the processor. The device can be a chip on the terminal device. In some implementations, the chip can be a system on a chip (System on a Chip, SoC).

[0400] It should be understood that the processor mentioned in the embodiments of the present invention may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0401] It should also be understood that the memory mentioned in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used 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 dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct memory bus random access memory (Direct Rambus RAM, DR RAM).

[0402] It should be noted that the memory described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0403] It should also be understood that the first, second and various numerical numbers involved in this document are only distinguished for the convenience of description and are not used to limit the scope of the present application.

[0404] In this application, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0405] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0406] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the steps shown in the figure do not necessarily need to be executed by the UE. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0407] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0408] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0409] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0410] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0411] 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 separately, or two or more units may be integrated into one unit.

[0412] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, network device or terminal device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0413] The relevant parts between the various method embodiments of the present invention can be referenced to each other; the device provided by each device embodiment is used to execute the method provided by the corresponding method embodiment, so each device embodiment can be understood by referring to the relevant parts of the relevant method embodiments.

[0414] The device structure diagrams provided in the device embodiments of the present invention only show the simplified design of the corresponding device. In practical applications, the device may include any number of transmitters, receivers, processors, memories, etc. to implement the functions or operations performed by the device in the device embodiments of the present invention, and all devices that can implement the present application are within the protection scope of the present application.

[0415] The names of the messages / frames / indication information, modules or units provided in the embodiments of the present invention are merely examples, and other names may be used as long as the functions of the messages / frames / indication information, modules or units are the same.

[0416] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms of "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items. The character " / " herein generally indicates that the objects associated before and after are in an "or" relationship.

[0417] It should be understood that, although the terms first, second, third, etc. may be used to describe various messages, requests, and terminals in the embodiments of the present invention, these messages, requests, and terminals should not be limited to these terms. These terms are only used to distinguish messages, requests, and terminals from each other. For example, without departing from the scope of the embodiments of the present invention, the first terminal may also be referred to as the second terminal, and similarly, the second terminal may also be referred to as the first terminal.

[0418] As used herein, the words “if” or “if” may be interpreted as “at the time of” or “when” or “in response to determining” or “in response to detecting”, depending on the context. Similarly, the phrases “if it is determined” or “if (stated condition or event) is detected” may be interpreted as “when it is determined” or “in response to determining” or “when detecting (stated condition or event)” or “in response to detecting (stated condition or event)”, depending on the context.

[0419] A person skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing related hardware through a program, and the program can be stored in a readable storage medium of a device. When the program is executed, it includes all or part of the above-mentioned steps, and the storage medium, such as FLASH, EEPROM, etc.

[0420] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that different embodiments can be combined. The above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any combination, modification, equivalent substitution, improvement, etc. made within the spirit and principles 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: The user equipment UE resides in the NR network; The UE receives a first operation by a user on an interface of the UE, where the first operation is used to disable a 5G communication capability of the UE; After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU procedure in the first LTE cell, where the TAU procedure includes the UE sending a TAU request to the first LTE cell; After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, where the second operation is used to enable the 5G communication capability of the UE; After receiving the second operation, if the UE meets a preset condition, the UE resides in the first NR cell and sends a first registration request to the first NR cell, where the first registration request carries indication information for indicating that the registration type is initial registration; wherein the UE meets the preset condition including: before the UE sends the first registration request to the first NR cell, the TAU process is in progress.

2. The method according to claim 1, characterized in that Before the UE sends the first registration request to the first NR cell, the TAU procedure is in progress, including: When the UE is preparing to send the first registration request to the first NR cell, or when the UE receives the second operation, the TAU procedure is in progress.

3. The method according to claim 1, characterized in that Before the UE sends the first registration request to the first NR cell, the TAU procedure is in progress, including: When the modem in the UE receives the second instruction, the TAU process is in progress, and the second instruction is a message sent by the application processor AP in the UE to the modem after the UE receives the second operation.

4. The method according to any one of claims 1 to 3, characterized in that The TAU process is in progress, which includes: the UE has not received a TAU reject message sent by the first LTE cell, and has not received a TAU accept message sent by the first LTE cell.

5. The method according to any one of claims 1 to 4, characterized in that The 5G communication capability of the UE includes the ability of the UE to communicate with the 5G network of the independent networking SA.

6. The method according to any one of claims 1 to 5, characterized in that The UE receives a second operation performed by a user on an interface of the UE, including: After sending the TAU request to the first LTE cell, the UE receives the second operation of the user on the interface of the UE.

7. The method according to any one of claims 3 to 6, characterized in that: The modem in the UE receives a second instruction, including: After the modem in the UE sends the TAU request to the first LTE cell, the modem receives the second instruction.

8. The method according to any one of claims 1 to 7, characterized in that The UE camping on the first LTE cell includes: After the modem in the UE receives the first instruction, the UE resides in the first LTE cell; wherein the first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

9. A communication method, characterized in that: The method comprises: The user equipment UE resides in the NR network; When the UE reselects to the LTE network, or the UE is redirected from the NR network to the LTE network, or the UE is switched from the NR network to the LTE network, or the UE is disabling the 5G communication capability of the UE, the UE resides in the first LTE cell and initiates a TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell; When the UE reselects to the NR network, or the UE is redirected from the LTE network to the NR network, or the UE switches from the LTE to the NR network, or the UE is executing to enable the 5G communication capability of the UE, and the UE satisfies a preset condition, the UE resides in a first NR cell and sends a first registration request to the first NR cell, where the first registration request carries indication information for indicating that the registration type is initial registration; wherein the UE satisfies the preset condition includes: before the UE sends the first registration request to the first NR cell, the TAU process is in progress.

10. The method according to claim 9, characterized in that Before the UE sends a first registration request to the first NR cell, the TAU procedure is in progress, including: The TAU process is in progress when the UE is preparing to send the first registration request to the first NR cell, or when the UE is executing to enable the 5G communication capability of the UE.

11. The method according to claim 9 or 10, characterized in that: The case where the UE is executing to enable the 5G communication capability of the UE includes: the UE receives a second operation of a user on an interface of the UE, where the second operation is used to enable the 5G communication capability of the UE; The situation in which the UE is executing to disenable the 5G communication capability of the UE includes: the UE receives a first operation of the user on the interface of the UE, and the first operation is used to disenable the 5G communication capability of the UE.

12. The method according to claim 11, characterized in that The case where the UE executes the operation to enable the 5G communication capability of the UE also includes: a modem in the UE receives a second instruction, where the second instruction is a message sent by the AP in the UE to the modem after the UE receives the second operation; The situation in which the UE executes disabling of the UE's 5G communication capability also includes: a modem in the UE receives a first instruction, and the first instruction is a message sent by the AP in the UE to the modem after the UE receives the first operation.

13. The method according to any one of claims 9 to 12, characterized in that: The TAU process is in progress, which includes: the UE has not received a TAU reject message sent by the first LTE cell, and has not received a TAU accept message sent by the first LTE cell.

14. The method according to any one of claims 9 to 13, characterized in that: The 5G communication capability of the UE includes the ability of the UE to communicate with the 5G network of the independent networking SA.

15. A communication method, characterized in that: The method comprises: The user equipment UE resides in the first network; The UE receives a first operation performed by a user on an interface of the UE, where the first operation is used to disable a communication capability of the UE on the first network; After receiving the first operation, the UE resides in a cell of a second network and initiates a first mobility location update process to the cell of the second network, where the first mobility location update process includes the UE sending a first mobility location update request to the cell of the second network; the standard of the second network is different from that of the first network; After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, where the second operation is used to enable the communication capability of the UE on the first network; After receiving the second operation, if the UE meets a preset condition, the UE resides in the cell of the first network and sends a first registration request to the cell of the first network, where the first registration request carries indication information for indicating that the registration type is initial registration; wherein the UE meets the preset condition including: before the UE sends the first registration request to the cell of the first network, the first mobility location update process is in progress.

16. A communication method, characterized in that: The method comprises: The user equipment UE resides in the first network; When the UE reselects to the second network, or the UE is redirected from the first network to the second network, or the UE is switched from the first network to the second network, or the UE is disabling the communication capability of the UE in the first network, the UE resides in a cell of the second network and initiates a mobility location update procedure to the cell of the second network, where the mobility location update procedure includes the UE sending a mobility location update request to the cell of the second network; When the UE reselects to the first network, or the UE is redirected from the second network to the first network, or the UE switches from the second network to the first network, or the UE enables the UE's communication capability in the first network, and the UE meets a preset condition, the UE resides in a cell of the first network and sends a first registration request to the cell of the first network, where the first registration request carries indication information for indicating that the registration type is initial registration; wherein the UE meets the preset condition includes: before the UE sends the first registration request to the cell of the first network, the mobility location update process is in progress.

17. A communication method, characterized in that: The method comprises: The user equipment UE resides in the NR network; The UE receives a first operation by a user on an interface of the UE, where the first operation is used to disable a 5G communication capability of the UE; After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU procedure in the first LTE cell, where the TAU procedure includes the UE sending a TAU request to the first LTE cell; After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, where the second operation is used to enable the 5G communication capability of the UE; After receiving the second operation, if the UE meets a preset condition, the UE resides in the first NR cell and sends a second registration request to the first NR cell, where the second registration request carries the TAU request; wherein the UE meets the preset condition including: before the UE sends the second registration request to the first NR cell, the TAU process is in progress.

18. The method according to claim 17, characterized in that The UE meeting the preset condition further includes: Before the UE sends the second registration request to the first NR cell, the UE is in a 5G MM-IDLE state, or, Before the UE sends the second registration request to the first NR cell, the UE is in a 5G MM-IDLE state, and the UE has received an indication from the NR network indicating that the NR network supports the N26 interface.

19. A communication method, characterized in that: The method comprises: The user equipment UE resides in the NR network; When the UE reselects to the LTE network, or the UE is redirected from the NR network to the LTE network, or the UE is switched from the NR network to the LTE network, or the UE is disabling the 5G communication capability of the UE, the UE resides in the first LTE cell and initiates a TAU process to the first LTE cell, and the TAU process includes the UE sending a TAU request to the first LTE cell; When the UE reselects to the NR network, or the UE is redirected from the LTE network to the NR network, or the UE network is executing to enable the 5G communication capability of the UE, and the UE satisfies a preset condition, the UE resides in the first NR cell and sends a second registration request to the first NR cell, and the second registration request carries the TAU request; wherein the UE satisfies the preset condition includes: before the UE sends the second registration request to the first NR cell, the TAU process is in progress.

20. A communication method, characterized in that: The method comprises: The user equipment UE resides in the NR network; The UE receives a first operation by a user on an interface of the UE, where the first operation is used to disable a 5G communication capability of the UE; After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU procedure in the first LTE cell, where the TAU procedure includes the UE sending a TAU request to the first LTE cell; After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, where the second operation is used to enable the 5G communication capability of the UE; the second operation is received after a first time period after the UE receives the first operation, or the second operation is received after the TAU process is successful; After receiving the second operation, the UE resides in the first NR cell and sends a third registration request to the first NR cell, where the third registration request carries the TAU request.

21. The method according to claim 20, characterized in that After the UE receives the first operation, the method further includes: The AP of the UE starts a first timer, where the timing duration of the first timer is the first duration; During the timing of the first timer, the UE enables the 5G communication capability of the UE to be configured as inoperable.

22. The method according to claim 21, characterized in that The method further comprises: When the first duration ends or a TAU Accept message corresponding to the TAU request is received, exit the first timer; After exiting the first timer, the UE enables the 5G communication capability of the UE to be configured to be operational.

23. The method according to claim 21 or 22, characterized in that The UE receiving the second operation includes: After the first timer exits, the UE receives the second operation.

24. A communication method, characterized in that: The method comprises: The user equipment UE resides in the NR network; The UE receives a first operation by a user on an interface of the UE, where the first operation is used to disable a 5G communication capability of the UE; After receiving the first operation, the UE resides in a first LTE cell and initiates a tracking area update TAU procedure in the first LTE cell, where the TAU procedure includes the UE sending a TAU request to the first LTE cell; After receiving the first operation, the UE receives a second operation of the user on the interface of the UE, where the second operation is used to enable the 5G communication capability of the UE; the second operation is received within a second time period after the UE receives the first operation, or the second operation is received before the TAU process is successful; After receiving the second duration of the first operation, or after the TAU process succeeds, the UE resides in the first NR cell and sends a fourth registration request to the first NR cell, where the fourth registration request carries the TAU request.

25. The method according to claim 24, characterized in that After sending the TAU request, the method further includes: The modem of the UE starts a second timer, where the timing duration of the second timer is the second duration; During the timing of the second timer, the modem of the UE caches the received information corresponding to the second operation.

26. The method according to claim 25, characterized in that The information corresponding to the second operation includes a second instruction, where the second instruction is a message sent by an application processor AP in the UE to the modem after the UE receives the second operation; After the UE receives the second operation, the method further includes: The modem of the UE receives the second instruction.

27. The method according to claim 25 or 26, characterized in that Before the UE camps on the first NR cell, the method further includes: When the timing of the second timer of the UE ends or a TAU Accept message corresponding to the TAU request is received, the UE exits the second timer.

28. The method according to claim 27, characterized in that After receiving the second duration of the first operation, or after the TAU process succeeds, the UE camps on the first NR cell and sends a fourth registration request to the first NR cell, including: After the second timer exits, the UE camps on the first NR cell and sends a fourth registration request to the first NR cell.

29. A terminal device, characterized in that: The terminal device includes: a memory and a processor for storing instructions; the processor is used to call and execute the instructions in the memory, so that the terminal device executes the method as described in any one of claims 1-8, or the terminal device executes the method as described in any one of claims 9-14, or the terminal device executes the method as described in claim 15, the terminal device executes the method as described in claim 16, the terminal device executes the method as described in any one of claims 17-18, or the terminal device executes the method as described in claim 19, or the terminal device executes the method as described in any one of claims 20-23, or the terminal device executes the method as described in any one of claims 24-28.

30. A chip system, characterized in that: The chip system includes a processor, which is used to support the terminal device to implement the method as described in any one of claims 1 to 8, or to support the terminal device to implement the method as described in any one of claims 9 to 14, or to support the terminal device to implement the method as described in claim 15, or to support the terminal device to implement the method as described in claim 16, or to support the terminal device to implement the method as described in any one of claims 17 to 18, or to support the terminal device to implement the method as described in claim 19, or to support the terminal device to implement the method as described in any one of claims 20 to 23, or to support the terminal device to implement the method as described in any one of claims 24 to 28.

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