Network registration method and terminal

Abstract

The invention provides a network registration method and a terminal. According to the method, the number of attempts of the Mo Detch is reduced, the duration of waiting for network response by the Mo Detch can be shortened, and therefore the process that the Mo Detch network does not respond is shortened, the terminal can go to other systems for network searching registration more quickly and restore to stay in the network more quickly, and better data service experience is brought.

Description

Technical Field

[0001] This application relates to the field of terminals and communication technologies, and particularly to a network registration method and a terminal. Background Art

[0002] Mobile communication networks have gone through multiple development stages. For example, they have evolved from the second-generation mobile communication network (2G network) to the third-generation mobile communication network (3G network), the fourth-generation mobile communication network (4G network), and then to the fifth-generation mobile communication network (5G network). The evolution from one generation of mobile communication network to another represents a development from one stage to another, and each stage brings new functions and improvements.

[0003] In some cases, a terminal will switch from one network to another, and how to improve the efficiency of the terminal switching from one network to another is worthy of discussion. Summary of the Invention

[0004] Embodiments of this application provide a network registration method and a terminal to improve the efficiency of a terminal switching from one network to another.

[0005] In a first aspect, embodiments of this application provide a network registration method, including: a terminal sending an Nth deregistration request to a first network, where the deregistration request is used to disconnect a first data connection with the first network; when the first network does not respond to the Nth deregistration request, the terminal is in a preset area, and the first network is a preset network, the terminal releases a packet switching (PS) domain link with the first network and initiates network search; where the PS domain link is used to implement the first data connection; the preset network includes a network with network quality lower than a preset condition in the preset area; when a second network is searched, the terminal sends a registration request to the second network, where the registration request is used to establish a second data connection with the second network; where N is a positive integer less than Z, and Z is the maximum number of attempts specified in a standard protocol for the terminal to send a deregistration request to the first network, and the standard protocol stipulates that the conditions for the terminal to release the PS domain link with the first network include: the deregistration request sent by the terminal is responded to by the first network, or none of the Z deregistration requests sent by the terminal are responded to.

[0006] In the above embodiment, the preset area may be an area with poor network quality of the first network. The first network at this time may be the following Figure 10 low-generation network involved in the following, or Figure 11The weak network involved. When the network quality of Network 1 is poor, the terminal reduces the number of attempts to initiate a deregistration (Mo detach) request to Network 1 (from Z to N), which can shorten the time for the terminal to wait for the first network's response to the deregistration request, enabling the terminal to ignore the response of Network 1 to the deregistration request more quickly, initiate a new network search, and then register to Network 2, achieving network switching more quickly. The reason for achieving network switching more quickly is as follows: When the network quality of Network 1 is poor, the first N deregistration requests sent by the terminal are likely to not be received by Network 1, so Network 1 cannot respond to the terminal's deregistration request. If following the previous standard protocol, after the Nth time, it is necessary to continue to initiate Z - N deregistration requests that are likely not to be responded to by Network 1. Only when all Z registration requests are not responded to by Network 1 can the terminal ignore the response and initiate a new network search.

[0007] Combined with the first aspect, in some embodiments, the network with network quality lower than the preset condition in the preset area includes the network with a network disconnection situation in the preset area, or the network with network quality lower than the preset condition in the preset area includes the network with a network coverage range lower than the preset level in the preset area.

[0008] The above embodiments consider the scenario where the existing standard protocol will no longer be applicable with the development of the mobile communication network. Or, it also considers the scenario where the uneven configuration of the mobile communication network in different regions leads to the existing standard protocol being unable to fully adapt to different regions.

[0009] Among them, the development of mobile communication networks includes: in the process of the evolution of mobile communication networks (referred to as networks), old networks gradually withdraw from the stage to make room for the birth and promotion of new networks. This transition from network withdrawal to the birth of new networks is carried out gradually to ensure that users can make a smooth transition. For example, the global system for mobile communications (GSM) and wideband code division multiple access (WCDMA) are both standard network formats in the field of mobile communications, corresponding to 2G (second-generation mobile communications) networks and 3G (third-generation mobile communications) networks, respectively. The two network formats of GSM and WCDMA were widely used in the field of mobile communications in the past, providing reliable voice communications and basic data transmission services. With the development of new generation mobile communication networks such as 4G (LTE) networks and 5G (NR) networks, the two network formats of GSM and WCDMA have been gradually eliminated in some areas, but are still used in some areas or specific scenarios. When the 4G network began to become popular, the 2G and 3G networks were not shut down immediately, but coexisted for a period of time to continue to serve users who are still using 2G and 3G networks. As time goes by and new technologies mature, old networks gradually withdraw from mobile communication networks, and mobile communication networks turn to the popularization and dominance of new networks.

[0010] The uneven configuration of mobile communication networks in different regions includes: although some networks have not been decommissioned, the network coverage of these networks in some areas is worse than that of the decommissioned networks. For example, in some countries, although 2G / 3G networks have been decommissioned, 4G / 5G networks have not been decommissioned. In some areas of these countries, the network coverage of 4G / 5G networks is worse than that of 2G / 3G networks.

[0011] In combination with the first aspect, in some embodiments, the method also includes: when the first network does not respond to the Nth deregistration request and the terminal is not in the preset area, or when the first network does not respond to the Nth deregistration request and the first network is not the preset network standard, the terminal initiates the N+1th deregistration request to the first network.

[0012] In the above embodiment, if the network quality of the first network is not bad, the original network configuration can be used to initiate more than N deregistration requests. Perhaps the deregistration request initiated after the Nth time can be responded to by the first network. In this way, the first network can know that the terminal wants to disconnect from itself, agree to the deregistration request and notify the terminal. The registration information of the terminal and the network side is kept consistent.

[0013] In combination with the first aspect, in some embodiments, the method further includes: after the terminal sends an i-th deregistration request to the first network, starting a T3321 timer, where i is greater than or equal to 1 and less than or equal to N; when the T3321 timer elapses for a preset duration, the terminal does not receive a response from the first network to the i-th deregistration request, and i is less than N, the terminal sends an (i + 1)-th deregistration request to the first network; when the terminal is in the preset area and the first network is of the preset network mode, the preset duration is a first duration; when the terminal is not in the preset area, or when the first network is not of the preset network, the preset duration is a second duration; the second duration is greater than the first duration; the second duration is the duration of the T3321 timer specified in the standard protocol.

[0014] In the above embodiments, in addition to reducing the number of times of sending deregistration requests, the duration of waiting for a response from the network (the first network) after sending a deregistration request is also shortened, so that the time for the terminal to wait for a response from the first network to the deregistration request can be further shortened, enabling the terminal to more quickly ignore the response from Network 1 to the deregistration request, initiate a new network search, and then register to Network 2, bringing a better data service experience.

[0015] In combination with the first aspect, in some embodiments, the network mode of the second network is higher than that of the first network, or the coverage range of the second network in the preset area is greater than that of the first network in the preset area.

[0016] In combination with the first aspect, in some embodiments, the second duration is 15 seconds and the first duration is 5 seconds.

[0017] In combination with the first aspect, in some embodiments, Z is equal to 5 and N is equal to 1.

[0018] In combination with the first aspect, in some embodiments, the method further includes: before the terminal sends a first deregistration request to the first network, the terminal determines that the activation of the data service fails.

[0019] In combination with the first aspect, in some embodiments, the registration request is further used to establish a voice call connection; the voice call connection is used to fallback from the second network to the first network for voice calls.

[0020] In the above embodiments, the registration request is the joint registration request involved in the following content. When switching from Network 1 to Network 2, joint registration can provide stronger fault tolerance and switching flexibility. For example, it can ensure that when the voice call quality in Network 2 is poor, the terminal can fallback to Network 1 to continue the voice call.

[0021] In combination with the first aspect, in some embodiments, the first network is a 2G or 3G network, and the second network is a 4G or 5G network; when the first network is a 2G network, the network mode of the first network includes the Global System for Mobile Communications (GSM) network mode; when the first network is a 3G network, the network mode of the first network includes the Wideband Code Division Multiple Access (WCDMA) network mode.

[0022] In a second aspect, the present application provides a network registration method, which includes: the terminal sends an Nth deregistration request to the first network, and the deregistration request is used to disconnect the first data connection with the first network; when the first network does not respond to the Nth deregistration request and there is a network outage in the area where the terminal is located, or, when the first network does not respond to the Nth deregistration request, there is no network outage in the area where the terminal is located but the network coverage of the first network in the area where the terminal is located is less than a preset level, the terminal releases the Packet Switching (PS) domain link with the first network and initiates a network search; wherein, the PS domain link is used to implement the first data connection; the preset network includes a network with network quality lower than a preset condition in the preset area; when a second network is searched, the terminal sends a registration request to the second network, and the registration request is used to establish a second data connection with the second network; wherein, N is a positive integer less than Z, and Z is the maximum number of attempts specified in the standard protocol for the terminal to send a deregistration request to the first network, and the standard protocol specifies that the conditions for the terminal to release the PS domain link with the first network include: the deregistration request sent by the terminal is responded to by the first network, or, none of the Z deregistration requests sent by the terminal are responded to.

[0023] In the above embodiments, when the network coverage of the first network is small (caused by network outage or uneven network distribution), the network quality of the first network will be poor. When the network quality of Network 1 is poor, the terminal reduces the number of attempts to send a deregistration (Mo detach) request to Network 1 (from Z to N), which can shorten the time for the terminal to wait for a response to the deregistration request from the first network, allowing the terminal to ignore the response to the deregistration request from the first network faster and initiate a new network search, and then register on Network 2, achieving network switching faster. The reason for achieving network switching faster is that when the network quality of Network 1 is poor, the first N deregistration requests sent by the terminal are likely to not be received by Network 1, so Network 1 cannot respond to the deregistration request from the terminal. If following the previous standard protocol, after the Nth time, it is necessary to continue to send Z - N deregistration requests that are likely not to be responded to by Network 1. Only when none of the Z registration requests are responded to by Network 1 can the terminal ignore the response and initiate a new network search.

[0024] In combination with the second aspect, in some embodiments, the network coverage of the first network in the area where the terminal is located is less than a preset level includes: the network coverage of the first network in the area where the terminal is located is less than the network coverage of other networks except the first network.

[0025] In combination with the second aspect, in some embodiments, when the first network does not respond to the Nth deregistration request, the first network does not exit the network in the area where the terminal is located, and the network coverage of the first network in the area where the terminal is located is greater than a preset level, the terminal initiates the N+1th deregistration request to the first network.

[0026] In combination with the second aspect, in some embodiments, the network coverage of the first network in the area where the terminal is located is greater than a preset level includes: there are other networks other than the first network in the area where the terminal is located, and the network coverage is smaller than the network coverage of the first network in the area where the terminal is located.

[0027] In a third aspect, the present application provides a network registration method. In some embodiments, the method includes: the terminal initiates N de-registrations to the first network; when it is determined that no response to the Nth de-registration has been received from the first network, the terminal initiates registration to the second network; wherein N is a positive integer less than Z, and Z is the standard number of registrations specified in the first network standard. The first network standard specifies that after the first registration initiated by the terminal to the first network fails, the conditions for stopping registration include: there is a successful registration between the second registration and the Zth registration, or, Z-1 registrations fail.

[0028] In the above embodiment, the number of deregistrations is reduced, and when the registration with the first network fails, the second network can be registered without being restricted by the network standard and the first network can be continuously tried to be registered.

[0029] In conjunction with the third aspect, in some embodiments, N is equal to 1.

[0030] In combination with the third aspect, in some embodiments, the method also includes: after the terminal initiates the i-th de-registration to the first network, starting timing; the value of i is an integer from 1 to N-1; when the timing reaches a first preset time and no response to the i-th de-registration is received from the first network, the terminal determines that the i-th registration has failed, and starts to initiate the i+1-th registration to the first network.

[0031] In combination with the third aspect, in some embodiments, the first preset time is less than a second preset time, and the second preset time is a registration waiting time specified by the first network standard.

[0032] In the above embodiment, the waiting time after each registration is reduced, and when there is a problem with the first network, the second network can be registered as soon as possible, so that the terminal maintains network connection.

[0033] In combination with the third aspect, in some embodiments, when the first network is a 2G network, the first network standard is the Global System for Mobile Communications (GSM) network standard; or, when the first network is a 3G network, the first network standard is the Wideband Code Division Multiple Access (WCDMA) network standard.

[0034] In combination with the third aspect, in some embodiments, the second network is an LTE network or an NR network.

[0035] In combination with the third aspect, in some embodiments, Z is equal to 5.

[0036] In combination with the third aspect, in some embodiments, when the first network standard is the GSM network standard or the WCDMA network standard, the first preset time is 5 seconds and the second preset time is 15 seconds.

[0037] In the above embodiments, the number of attempts of Mo detach is reduced, and the duration of waiting for the network response of Mo Detach is shortened, thereby significantly shortening the process of Mo Detach without network response, enabling the UE to search for and register with other standards faster, resume camping on the network faster, and bringing a better data service experience.

[0038] Fourth aspect, an embodiment of the present application provides a terminal, which includes: one or more processors and a memory; the memory is coupled to the one or more processors, and the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the terminal to execute the method implemented in the first aspect.

[0039] Fifth aspect, an embodiment of the present application provides a computer-readable storage medium, including instructions, when the instructions run on the terminal, enabling the terminal to execute the method implemented in the first aspect.

[0040] Sixth aspect, an embodiment of the present application provides a chip system, which is applied to a terminal, the chip system includes one or more processors, and the processors are used to call computer instructions to enable the terminal to execute the method implemented in the first aspect. The chip system may be a System-on-Chip (SoC). The processor may include a modulation and demodulation processor (also known as a Modem or a baseband chip).

[0041] Seventh aspect, an embodiment of the present application provides a computer program product containing instructions, when the computer program product runs on the terminal, enabling the terminal to execute the method implemented in the first aspect.

[0042] Understandably, the terminal provided by the fourth aspect, the computer storage medium provided by the fifth aspect, the chip system provided by the sixth aspect, and the computer program product provided by the seventh aspect are all used to execute the method provided by the embodiments of the present application. Therefore, other beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be elaborated here. Description of the Drawings

[0043] Figure 1 It shows a schematic diagram of a scenario for switching from one network to another network;

[0044] Figure 2 It is an exemplary mobile communication network provided by the embodiments of the present application;

[0045] Figure 3 It shows a processing flow chart of GPRS Mo Detach in standard GSM / WCDMA;

[0046] Figure 4 It shows a schematic diagram of a scenario where the terminal cannot deregister to camp on an available network when the signal of a low-generation network is weak;

[0047] Figure 5 It shows a processing flow chart of GPRS Mo Detach in the modified network configuration;

[0048] Figure 6 It shows a schematic diagram of a scenario where the terminal quickly camps on an available network when the signal of a low-generation network is weak;

[0049] Figure 7 It shows an exemplary flowchart of Mo Detach of the terminal in Usage Scenario 1;

[0050] Figure 8 It shows a schematic diagram of the terminal switching from one low-generation network to another low-generation network;

[0051] Figure 9 It shows a schematic diagram of the terminal switching from a low-generation network to another high-generation network;

[0052] Figure 10 It shows an exemplary flowchart of Mo Detach of the terminal in Usage Scenario 2;

[0053] Figure 11 It shows an exemplary flowchart of Mo Detach of the terminal in Usage Scenario 3;

[0054] Figure 12 It is a schematic structural diagram of the terminal provided by the embodiments of the present application. Detailed Embodiments

[0055] In one solution, for a terminal (user equipment, UE) that supports at least two mobile communication networks, when the signal of the connected network (mobile communication network) becomes weak or the signal is interrupted, resulting in unsmooth or even difficult data services, the terminal can send a deregistration request to the connected network to disconnect the data connection with the connected network, and send a registration request to other networks except the connected network. This registration request is used to attempt to register to this other network, establish a new data connection with this other network, and then use the data transmission service provided by this other network. In this way, the terminal can maintain the continuity of the data connection to complete the data service.

[0056] The terminal deregistering from one network and then registering to another network can be referred to as network handover. This network handover usually occurs when the area where the terminal is located changes. As Figure 1 shown, when the user is on a high-speed train and the train travels from high-speed railway station A to high-speed railway station B, the terminal will move from area A covered by 4G / 5G network to area B covered by 2G / 3G network. In area A, the terminal can display user interface 11. Referring to the network indicator 115 in user interface 11, this indicates that the terminal has established a data connection A with the 4G network. When the terminal leaves area A and enters area B, when the terminal attempts to send message 112 to other terminals through data connection A, a loading indicator 111 appears next to the message box. And this loading indicator 111 does not disappear for a long time (from 17:59 - 18:00), which indicates that the signal of the 4G network connected to the terminal becomes weak or the signal is interrupted. At this time, the terminal can send a deregistration request to the connected 4G network to disconnect data connection A.

[0057] Continuing to refer to Figure 1 , after entering area B, the terminal can search for an available 3G network and send a registration request to this 3G network to establish a new data connection (data connection B) with the 3G network. In area B, the terminal can display user interface 12. Referring to the network indicator 113 in user interface 12, this indicates that the terminal has established a data connection B with the 3G network. As shown in user interface 12, the terminal successfully sends message 112 to other terminals through data connection B.

[0058] It should be understood that after the terminal is registered to the 3G network, if area B is large enough and the signal of the 3G network is good, the longer the terminal maintains the data connection B. However, as the train moves away from area B, the signal of the 3G network will gradually weaken. For example, referring to the user interface 13, when the terminal attempts to send a message 131 to other terminals through the data connection B, a loading indicator 111 appears around the message box. This indicates that the signal of the 3G network to which the terminal is connected has weakened. At this time, the terminal can initiate a deregistration request to the connected 3G network to disconnect the data connection B and attempt to register to the network covered by the next area.

[0059] It should be noted that after establishing a data connection with the connected network, through the link established by this data connection, the terminal can connect to the packet switching (PS) domain of the connected network. The PS domain provides the technology and processing mechanism for transmitting data, thus realizing the data transmission between the terminal and the connected network. Once the terminal successfully deregisters, it will no longer be able to continue data services on the connected network. Among them, the link established through this data connection can also be called a PS domain link.

[0060] The aforementioned data service refers to the service or operation carried out through the PS domain of the connected network, and usually the amount of data transmitted in the network when completing the data service is measured by traffic. Common data services include browsing the web, sending emails, watching videos, using social media, etc.

[0061] Since the data service is completed through the PS domain of the connected network, the aforementioned deregistration request for disconnecting the data connection can be called a PS domain deregistration request. The aforementioned registration request for establishing a data connection can be called a PS domain registration request (PS Attach). Among them, the deregistration in the PS domain deregistration can also be called de-registration.

[0062] At present, the networks supported by the terminal include but are not limited to at least two of the following networks: 2G network, 3G network, 4G network, and 5G network. In the future, there may also be more available mobile communication networks, which are not limited here. The following combines Figure 2 Describe the relevant content involved when the terminal establishes a data connection with the network through the PS domain registration request, and the relevant content involved when the terminal disconnects the data connection with the network through the PS domain deregistration request.

[0063] Here, the network is taken as an example of the 5G network for illustration. Other networks except the 5G network can refer to the description of the 5G network and will not be elaborated.

[0064] Refer to Figure 2As shown in the figure, a 5G network may include 5G base stations, a 5G core network (5GC), and other 5G components.

[0065] The 5G base station may be a next generation NodeB (gNB). The 5G base station can be connected to a terminal and at the same time connected to the 5G core network. The 5G base station plays a role in signal forwarding and scheduling, enabling the terminal to communicate with the 5G core network.

[0066] The 5G core network is the central control part of the 5G network, responsible for managing and controlling the operation of the entire network. For example, the PS domain in the 5G network depends on the support of the 5G core network, and realizes data transmission with the terminal through the control and management of the 5G core network.

[0067] An exemplary process for a terminal to establish a data connection with the 5G network includes the following.

[0068] When a terminal wishes to connect to the 5G network and initiate data transmission, it first needs to establish a physical connection with the 5G base station. Subsequently, the terminal sends a PS domain registration request through this physical connection. The PS domain registration request is a message sent by the terminal to the connected 5G base station, used to indicate to the 5G network that the terminal wishes to connect to the 5G network and use the data services in the PS domain. The PS domain registration request contains the identification information of the terminal (such as the International Mobile Station Identity IMSI) and the PS domain service requirements, etc. The PS domain service requirement refers to requesting the 5G network to provide a data connection service in the PS domain for the terminal to ensure that the terminal can perform data transmission.

[0069] Then, the 5G base station will initially verify the identity of the terminal and the legality of the PS domain registration request based on the PS domain registration request. After the verification passes, the PS domain registration request will be sent from the 5G base station to the 5G core network. Subsequently, the 5G core network processes the PS domain registration request: including further verifying the identity of the terminal, checking the PS domain service requirements, authorizing and allocating corresponding resources (such as IP addresses, etc.) to generate configuration information. If the registration is successful, the 5G core network returns the configuration information to the 5G base station. After receiving the configuration information returned by the 5G core network, the 5G base station configures the resources involved in the terminal's data transmission according to the configuration information.

[0070] An exemplary process for a terminal to disconnect the data connection with the 5G network includes the following.

[0071] First, the terminal sends a PS domain deregistration request to the connected 5G base station. The PS domain deregistration request includes the identification information of the terminal and the reason for deregistration. The terminal notifies the 5G base station that it hopes to cancel the registration in the PS domain and disconnect the data connection. The 5G base station will process the PS domain deregistration request. If the 5G base station agrees to deregister, it will notify the 5G core network of the deregistration information of the terminal.

[0072] Subsequently, the 5G core network determines whether to agree to deregister based on the identification of the terminal and the reason for deregistration in the deregistration information, and generates a deregistration response. The deregistration response includes the result of the PS deregistration operation, such as successful deregistration or failed deregistration. If the deregistration is successful, the 5G core network updates the registration status of the terminal. In this way, the 5G core network knows that the terminal has been deregistered and the data connection has been disconnected. Moreover, the 5G core network sends the deregistration response to the terminal through the 5G base station.

[0073] After receiving the deregistration response, the terminal performs subsequent operations based on the result of the PS deregistration operation therein: if the result of the PS deregistration operation is successful deregistration, the terminal releases the PS domain link with the 5G network to disconnect the data connection with the 5G network. If the result of the PS deregistration operation is failed deregistration, the terminal can re-attempt PS domain deregistration. Here, the relevant content involved in the case of failed deregistration can refer to the following description of Figure 2 and its related content, which will not be elaborated here.

[0074] Refer again to Figure 2 As shown, the 4G network may include 4G base stations, a 4G core network (evolved packet core, EPC), and other 4G components.

[0075] The 4G base station can be an evolved Node B (eNB). The 4G base station can be connected to the terminal and at the same time connected to the 4G core network. The 4G base station plays a role in signal forwarding and scheduling, enabling the terminal to communicate with the 4G core network.

[0076] The 4G core network is the central control part of the 4G network, responsible for managing and controlling the operation of the entire network. For example, the PS domain in the 4G network depends on the support of the 4G core network and realizes data transmission with the terminal through the control and management of the 4G core network.

[0077] The process of the terminal establishing or disconnecting a data connection with the 4G network is similar to the process of the terminal establishing or disconnecting a data connection with the 5G network mentioned above. One can refer to the process of the terminal establishing or disconnecting a data connection with the 5G network above and just change 5G to 4G.

[0078] Refer again toFigure 2 As shown in the figure, components such as 2G / 3G base stations and 2G / 3G core networks can be included in the 2G / 3G network.

[0079] The 2G base station can be a base transceiver station (BTS), and the 3G base station can be a NodeB. The terminal can be connected to the 2G / 3G base station. The 2G / 3G base station plays a role in signal forwarding and scheduling, enabling the terminal to communicate with the 2G / 3G core network.

[0080] It should be noted here that the network mode for communication in the 2G network includes the global system for mobile communications (GSM) network mode. GSM uses time division multiple access (TDMA) technology, enabling the 2G network to provide services such as data transmission and voice calls.

[0081] The network mode for communication in the 3G network includes the wideband code division multiple access (WCDMA) network mode. WCDMA uses code division multiple access (CDMA) technology, enabling the 3G network to provide faster (compared to the 2G network) data transmission services and also voice call services.

[0082] The network mode for communication in the 4G network includes the long-term evolution (LTE) network mode. LTE uses the internet protocol (IP) network architecture and orthogonal frequency division multiple access (OFDMA) technology, enabling the 4G network to provide faster (compared to the 3G network) data transmission services and also more stable (compared to the 3G network) voice call services.

[0083] The network mode for communication in the 5G network includes the new radio (NR) network mode. NR uses a brand-new radio access technology and realizes services such as high-speed data transmission and stable voice calls.

[0084] Among them, the data transmission services provided by 2G / 3G / 4G / 5G networks are completed based on the PS domain involved above. In 2G / 3G networks, the PS domain is also known as the general packet radio service (GPRS) domain. The voice call services provided by 2G / 3G networks are completed based on the circuit switched (CS) domain. The voice call services provided by 4G networks are mainly completed through VoLTE technology in the IP multimedia subsystem (IMS) domain. The voice call services provided by 5G networks are mainly completed through VoNR technology in the IMS domain.

[0085] The above content introduced the network modes used in the existing network (such as 2G / 3G / 4G / 5G networks). Next, it will introduce how the terminal realizes network switching based on each network mode (GSM / WCDMA / LTE / NR).

[0086] When the existing network (such as 2G / 3G / 4G / 5G networks) encounters a situation where the terminal has no response to the activation of data services on the standard GSM / WCDMA / LTE / NR, it will attempt to initiate the mobile-originated detach (MoDetach) and reattach of the PS domain initiated by the mobile terminal to the connected network (GSM corresponds to the 2G network, WCDMA corresponds to the 3G network, LTE corresponds to the 4G network, NR corresponds to the 5G network) to an available network to restore data services. However, since the connected network does not respond to the MoDetach initiated by the terminal, the terminal remains in the attempt to detach state for a long time.

[0087] It should be noted that the mobile-originated detach initiated by the PS domain mobile terminal can also be simply referred to as Detach.

[0088] In the attempt to detach state, the terminal cannot attempt to search for and register on other network modes, making the terminal unable to camp on other mode networks (such as higher mode networks with a higher network mode than the connected network), thereby affecting the data services of the terminal.

[0089] In standard GSM or WCDMA, it is stipulated that after the terminal (UE) initiates a Mo Detach attempt and fails to register, it needs to continue to initiate a Mo Detach attempt to register. And after each Mo Detach attempt to register, the terminal must wait for h (usually 15s) seconds before it can initiate the next Mo Detach attempt to register again. It is not until x (usually 5 times) attempts to register all fail that it can ignore the response of the 2G / 3G network to the detach registration, and then it can attempt to register to a network other than the 2 / 3G network, such as a 4G network or a 5G network, etc. This process can be as follows Figure 3 shown in the process

[0090] As Figure 3 shown, the process of the terminal initiating Mo Detach in standard GSM or WCDMA includes steps S1 - S7.

[0091] S1. The UE initiates a Mo Detach to the network and starts the T3321 timer (15 seconds) at the same time. It is expected that the terminal gets a response from the network (GSM corresponds to the 2G network, WCDMA corresponds to the 3G network) before the T3321 timer times out.

[0092] In some implementation manners, when the terminal has no response to the activation of data service on standard GSM, it can attempt to initiate a Mo Detach to the 2G network to request to disconnect the data connection with the 2G network. When the terminal has no response to the activation of data service on standard WCDMA, it can attempt to initiate a Mo Detach to the 3G network to request to disconnect the data connection with the 3G network.

[0093] When initiating a Mo Detach, the terminal also starts the T3321 timer for measuring time. When the time measured by the T3321 timer reaches the protocol time (15s), it triggers the terminal to perform relevant operations.

[0094] When the number of times of initiating a Mo Detach is less than the maximum number of attempts, the relevant operation is to initiate a Mo Detach again. Refer to the following description of steps S2 - S4.

[0095] When the number of times of initiating Mo Detach equals the maximum number of attempts, the relevant operation is to stop waiting for the network response, directly release the link and initiate a new network search and registration. Refer to the following description of step S5. It should be noted that when the time measured by the T3321 timer does not reach the protocol time (15 s), if the terminal receives a network response to Mo Detach, the terminal can make corresponding processing based on the response and clear the number of times of initiating Mo Detach. Among them, the content of making corresponding processing based on the response can refer to the previous description of the deregistration response and its related content. It will not be elaborated here.

[0096] S2. During the effective period of the T3321 timer, the terminal does not receive the Mo Detach initiated by the network response, resulting in the T3321 timer timing out once.

[0097] That is, before the T3321 timer times out, if the terminal does not receive the response to Mo Detach sent by the network (2G network or 3G network), the terminal records that the T3321 timer times out once. This indicates that the terminal's first attempt to initiate Mo Detach to register fails.

[0098] S3. The UE initiates Mo Detach to the network for the second time and starts the T3321 timer (15 seconds) again. It is expected that the terminal gets a network response (GSM corresponds to the 2G network, WCDMA corresponds to the 3G network) before the T3321 timer times out.

[0099] S4. The T3321 timer times out twice.

[0100] In step S4, the T3321 timer timing out twice includes: before the second timeout of the T3321 timer, when the terminal does not receive the response to Mo Detach sent by the network (2G network or 3G network), the terminal records that the number of times the T3321 timer times out is incremented by 1, changing from 1 time to 2 times.

[0101] Then, the UE initiates Mo Detach to the network (2G network or 3G network) for the third time and starts the T3321 timer (15 seconds) for the third time. Before the third timeout of the T3321 timer, the terminal does not receive the response to Mo Detach sent by the network (2G network or 3G network), and the T3321 timer times out three times.

[0102] After the third attempt to register fails, the UE initiates Mo Detach to the network (2G or 3G network) for the fourth time and starts the T3321 timer (15 seconds) for the fourth time. Before the fourth timeout of the T3321 timer, the terminal does not receive the response to Mo Detach sent by the network (2G network or 3G network), and the T3321 timer times out four times.

[0103] After the 4th attempt to register fails, the UE initiates a Mo Detach to the network (2G or 3G network) for the 5th time, and starts the T3321 timer (15 seconds) for the 5th time. Before the T3321 timer times out for the 5th time, the terminal does not receive a response to the Mo Detach sent by the network (2G network or 3G network), and the T3321 timer times out 5 times.

[0104] After the UE fails to register in 5 attempts to initiate Mo Detach, the following steps S5 - S7 are executed, and the UE starts to initiate network search to register to a network other than the 2G or 3G network.

[0105] Step S5. According to the protocol, after the T3321 timer times out 5 times, the UE no longer waits for the network response, directly releases the link and initiates a new network search for registration.

[0106] Releasing the link (releasing the data link) means that the terminal releases the PS domain link with the connected network. The terminal's execution of releasing the link includes: closing the communication channel used for data transmission with the connected network, releasing the resources used for data transmission (such as IP addresses, etc.). Completing the release of the link indicates that the terminal disconnects the data connection with the connected network.

[0107] Here, taking the newly searched network as a high - standard network such as an LTE network or an NR network as an example, the relevant content of the terminal registering to the high - standard network can be referred to the following descriptions of steps S6 and S7.

[0108] S6. The UE initiates a registration request to the high - standard network.

[0109] Here, the "high - standard" in the high - standard network is a relative concept, indicating that the 4G / 5G network has a higher network standard than the 2G / 3G network. It does not mean that the high - standard network can only be the 4G / 5G network. In fact, in different scenarios, the high - standard network can be different networks. For example, when the network connected by the terminal is a 2G network, the 3G network is also considered a high - standard network.

[0110] S7. The network accepts the UE's registration request.

[0111] The network in step S7 can be a 4G / 5G network (LTE corresponds to the 4G network, and NR corresponds to the 5G network).

[0112] After the network accepts the registration request initiated by the UE, the UE can establish a new data connection with the high - standard network.

[0113] It should be noted that the protocols involved in the foregoing step S5 include the 3rd generation partnership project (3GPP) protocol. The 3GPP protocol includes a variety of communication standards, such as the aforementioned GSM, WCDMA, LTE, and NR.

[0114] Among them, when the network connected by the terminal is a 2G / 3G network, the Mo Detach initiated by the terminal can also be referred to as GRPS Mo Detach (mobile original GPRS detach without switching off).

[0115] The foregoing Figure 3 is an example of camping on a higher-generation network after the terminal disconnects the data connection from the connected network. In fact, in some possible cases, the terminal can also camp on a network with a lower generation than the connected network, or can camp on the connected network again. After disconnecting the data connection from the connected network, which network to switch to specifically is selected according to factors such as network signal strength, availability, and the network setting priority of the terminal.

[0116] Here it should be noted that Figure 3 takes the example of initiating Mo Detach (GPRS Mo Detach) from a standard GSM or WCDMA to a 2G / 3G network for illustration. In fact, it is not limited to 2G / 3G networks. When the network connected by the terminal is a 4G / 5G network, the processing flow of initiating Mo Detach from a standard LTE or NR to a 2G / 3G network is also Figure 3 the shown process, and corresponding modifications can be made. For example, modify GSM to LTE and WCDMA to NR. When the network connected by the terminal is a 4G network, the higher-generation network obtained by network search can be a 5G network. When the network connected by the terminal is a 4G network, the available networks obtained by network search can be one of a 4G network, a 3G network, or a 2G network.

[0117] Among them, when the network connected by the terminal is a 4G / 5G network, the Mo Detach initiated by the terminal to the connected network can also be referred to as EPS Mo Detach (mobile original EPS detach without switching off).

[0118] As Figure 3The processing flow of the GPRS Mo Detach shown starts the T3321 timer when the GPRS Mo Detach is initiated. If the network does not respond, the UE will attempt 5 times, with each attempt timed out by the T3321 timer (15s). After reaching 5 times, the UE will no longer wait and will actively complete the GPRS detach process. If the network (2G / 3G network) cannot respond to the GPRS Mo Detach initiated by the UE, resulting in the T3321 timer timing out multiple times, it will cause the UE to be in the registration attempt state for a long time (e.g., 15×5 = 75), making it impossible to quickly switch networks.

[0119] In the case where the 2G network and 3G network deployments are relatively mature, the network (2G / 3G network) can quickly respond to the Mo Detach initiated by the UE. Therefore, the impact on the UE is relatively small. However, as the 2G / 3G network gradually retires, the problem caused by the network (2G / 3G network) being unable to respond to the GPRS Mo Detach initiated by the UE, resulting in the T3321 timer timing out multiple times, will become more and more obvious, and the scope and frequency of the impact will also gradually increase. Therefore, this process has become inapplicable at the current stage of the gradual retirement of the 2G / 3G network.

[0120] Among them, the network (2G / 3G network) that is gradually retiring has relatively poor performance compared to the subsequent network (e.g., 4G / 5G network). For example, the data transfer rate is relatively low. Therefore, this gradually retiring network can also be called a low-generation network.

[0121] Based on the foregoing, a low-generation network (e.g., 2G / 3G network) encounters a terminal (UE) initiating a GPRS Mo Detach to the network on GSM / WCDMA. However, due to network retirement, the coverage area of the network decreases, resulting in a weak signal. Therefore, the low-generation network does not respond to the GPRS Mo Detach initiated by the UE, causing the UE to be in the registration attempt state for a long time (e.g., 15×5 = 75). During this period, the UE cannot attempt to search for and register on other generations of networks, thus affecting the UE's data service Internet experience and residence on high-generation networks. Refer to Figure 4 , which shows a schematic diagram of the scenario where a terminal (UE) cannot deregister to reside on an available network when the signal of the low-generation network is weak.

[0122] As Figure 4 shown, when the user is on a high-speed train traveling from high-speed railway station A to high-speed railway station B, the terminal will move from area 1 covered by the 4G / 5G network to area 2 covered by the 2G / 3G network, and then from area 2 covered by the 2G / 3G network to area 3 covered by the 4G / 5G network. Correspondingly Figure 1In the scenario where the 2G / 3G network is retired, the coverage area of the 2G / 3G network will shrink from Figure 1 Area B shown in Figure 4 to Area 2 shown in

[0123] In Area 2, the terminal can display User Interface 21 and User Interface 22. Referring to the network indicator 113 in User Interface 21 and User Interface 22, this indicates that the terminal has established a data connection 1 with the 3G network and sent a message 221 through this data connection, which means that the 3G network signal to which the terminal is connected is good at this time. Figure 3 However, when the terminal leaves Area 2 and enters Area 3, the network covered by Area 3 is the 4G / 5G network, and the terminal cannot complete data transmission using the 3G network. The terminal executes the method shown in

[0124] and sends a Mo Detach to the 3G network on the standard WCMDA. However, there is no 3G network in Area 3 anymore, and the sent Mo Detach cannot get a response from the 3G network. Therefore, the terminal will try Mo Detach multiple times and be in the registration attempt state for a long time, and cannot switch to the available 4G / 5G network in time in Area 3 where the 4G / 5G network is covered, resulting in the terminal being unable to complete data transmission and affecting the user experience.

[0125] Among them, the exemplary scenarios where the terminal cannot complete data transmission can refer to User Interface 23 - User Interface 25. As shown in User Interface 23 and User Interface 24, when the terminal tries to send a message 281 to another terminal through the data connection 1, a loading indicator 111 appears next to the message box. Referring to User Interface 24 and User Interface 25, the terminal still cannot complete the message sending through the data connection 1 for a long time (for example, from 18:00 to 18:01), and a "Send Failure" indicator 251 is displayed around the message box for sending the message 231 to prompt the user that the data transmission cannot be completed.

[0125] In another solution, for the scenario where the UE initiates a Mo Detach to a lower-generation network and the lower-generation network does not respond to the Mo Detach, resulting in the timeout of the T3321 timer. The number of attempts for the T3321 timer timeout defined in the original protocol (such as the standard GSM or WCDMA) is reduced from x (usually 5) times to y times (0 < y < x), and the duration of the T3321 timer is shortened from h (usually 15) seconds to i seconds (0 < i < h), obtaining a modified network configuration. For example, y = 5 and i = 1. That is, after the UE tries a Mo Detach once and gets no response, it no longer waits for the network response, directly releases the link locally and tries to search for and register to other generations of networks.

[0126] Compared with the original protocol process (refer to Figure 3) This solution uses a modified network configuration for MoDetach, significantly shortening the waiting duration for the Mo Detach network to become unresponsive. The process of this solution is as follows Figure 5 as shown (taking y = 1, i = 5 as an example).

[0127] Among them, the low - mode network includes 2G / 3G networks, and the modified network configuration includes network configurations applicable to GSM (corresponding to 2G networks) and / or WCDMA (corresponding to 3G networks).

[0128] As Figure 5 shown, the process for the terminal to initiate Mo Detach in the modified network configuration can refer to the following steps S11 - step S15.

[0129] S11. The UE initiates Mo Detach to the network and simultaneously starts the T3321 timer (5 seconds). It is expected that the terminal gets a response from the network (GSM corresponding to 2G network, WCDMA corresponding to 3G network) before the T3321 timer times out.

[0130] For the content of this step S11, it can refer to the description of step S1 above and make appropriate adaptations (for example, modify the timeout time of the T3321 timer from 15 seconds to 5 seconds).

[0131] S12. During the period when the T3321 timer is in effect, the terminal does not receive the network response to the initiated Mo Detach, resulting in the T3321 timer timing out once.

[0132] Before the T3321 timer times out, the terminal does not receive the response from the network to Mo Detach. The terminal's first attempt to initiate Mo Detach to register fails.

[0133] After the T3321 timer times out once, the UE no longer waits for the network (2 / 3G network) response, directly releases the link and initiates a new network search and registration. For this process, it can refer to the following description of steps S13 - step S15.

[0134] Among them, the content related to releasing the link can refer to the relevant description of releasing the link in step S5 above, and will not be elaborated here.

[0135] S13. The UE no longer waits for the network response, directly releases the link locally and initiates a new network search and registration.

[0136] Here, it is illustrated by taking the newly searched network as a high - mode network such as LTE (corresponding to 4G network) or NR (corresponding to 5G network) as an example.

[0137] S14. The UE initiates a registration request to the high - mode network.

[0138] S15. The network receives the UE registration request.

[0139] Regarding the content of steps S14 and S15, reference can be made to the foregoing descriptions of steps S6 and S7, and details are not repeated here.

[0140] In this way, compared with the original protocol process ( Figure 3 shown in), this solution ( Figure 5 shown in) mainly reduces the number of attempts of MoDetach, and can also shorten the duration of waiting for the network response during Mo Detach, thereby significantly shortening the process of no network response during MoDetach, enabling the UE to search for and register with other network modes faster, resume camping on the network faster, and bringing a better data service experience. Refer to Figure 6 , which is an exemplary scenario for the terminal (UE) to quickly camp on the available network when the signal of the low-generation network is weak.

[0141] Figure 6 In the scenario shown in, the user is on a high-speed train, and when the train travels from high-speed railway station A to high-speed railway station B, the terminal will move from area 1 covered by 4G / 5G network to area 2 covered by 2G / 3G network, and then move from area 2 covered by 2G / 3G network to area 3 covered by 4G / 5G network. In area 1, the terminal can camp on the 4G / 5G network. When it reaches area 2, the terminal can camp on the 2G / 3G network. In area 2, the user interfaces involved in data transmission by the terminal can be user interface 21 and user interface 22. The data transmission process of the terminal in area 2 is the same as that in area 2 in the foregoing Figure 4 , and details are not repeated here.

[0142] When the terminal leaves area 2 and enters area 3, the network covered by area 3 is 4G / 5G network, and the terminal cannot complete data transmission using the 3G network. The terminal executes the method shown in the foregoing Figure 5 and sends MoDetach to the 3G network on WCMDA. Even if there is no 3G network in area 3 anymore, the sent Mo Detach cannot get a response from the 3G network. However, the number of attempts of the terminal to perform Mo Detach is reduced, and the timer timeout time is shortened. Then, compared with Figure 4 , it will not cause the terminal to be in the registration attempt state for a long time. Refer to Figure 6 The user interface 31 in, and in area 3 covered by 4G / 5G network, it can be quickly switched to the available 4G / 5G network, enabling the terminal to complete the transmission of data (message 1411).

[0143] Therefore, based on the foregoing content, it can be seen that with the reduction of the verification times and the shortening of the timer, the terminal can return to the high-generation network faster.

[0144] It should also be noted that it is not limited to the process where the network has no response after the UE initiates a GRPS Mo Detach due to the "GPRS detach without switching off" type. As long as the UE enters the Mo Detach process (including GPRS detach with switching off and EPS detach without switching off initiated by the terminal side), then Figure 5 the shortening of the Mo Detach process shown in

[0145] is also equally applicable. Among them, GPRS detach without switching off is the aforementioned GPRS Mo Detach, which occurs when the network connected by the terminal is a 2G / 3G network. EPS detach without switching off is the aforementioned EPS Mo Detach, which occurs when the network connected by the terminal is a 4G / 5G network.

[0146] That is to say, although Figure 5 it is for shortening the Mo Detach (GPRS Mo Detach) process under GSM and WCDMA (GSM corresponds to the 2G network, and WCDMA corresponds to the 3G network). However, the current protocol (3GPP protocol) has a similar processing process for EPS Mo Detach under LTE and NR (LTE corresponds to the 4G network, and NR corresponds to the 5G network). Therefore, the present invention is also equally applicable to LTE and NR (LTE corresponds to the 4G network, and NR corresponds to the 5G network). For example, in the scenario where a network newer than the 4G / 5G network appears in the future and the 4G network and 5G network need to gradually withdraw from the network, Figure 5 the shortening of the GPRS Mo Detach process shown in

[0147] can be applied to EPS Mo Detach to achieve the shortening of the EPS Mo Detach process.

[0148] It should be noted that in the foregoing content, the number of Mo Detach is clearly shortened to 1 time, and the duration of the T3321 timer (timeout time) is clearly shortened to 5 seconds. However, the number and duration can be adjusted according to the actual network deployment and response situation.

[0149] For example, in a usage scenario (Usage Scenario 1), the network configuration used by the low-mode network in the terminal is the modified network configuration. The modification includes: modifying the number Z (maximum number of attempts) of Mo Detach in the standard network configuration to a preset number N (less than the maximum number of attempts), and / or modifying the duration (protocol time) of the timeout of the T3321 timer in the standard network configuration to a preset time (less than the protocol time). The standard network configuration can be regarded as a standard protocol. The conditions specified in the standard protocol for the terminal to release the PS domain link with the connected network include: the deregistration request initiated by the terminal is responded to by the connected network, or none of the Z deregistration requests initiated by the terminal are responded to.

[0150] In Usage Scenario 1, the terminal initiates N deregistration requests to the connected low-mode network through the modified network configuration. When the terminal determines that the low-mode network does not respond to the Nth deregistration request, the terminal releases the PS domain link with the low-mode network and initiates a network search. In the case of finding an available network, the terminal initiates a registration request to the available network 1, and this registration request is used to establish a new data connection with the available network 1.

[0151] For a detailed description of this process, reference can be made to the description of steps S101 - S107 in the following Figure 7 below.

[0152] S101. The terminal determines that the low-mode network 1 does not respond to the data service activation request.

[0153] Here, the low-mode network 1 is the low-mode network connected to the terminal.

[0154] When the terminal wants to perform a data service, it will initiate a data service activation request to the low-mode network 1. If the terminal does not receive a response from the low-mode network 1 to the data service activation request within a certain period of time, the terminal determines that the low-mode network 1 does not respond to the data service activation request.

[0155] In step S101, the reasons for the data service activation request of the low-mode network 1 can include: the low-mode network 1 is in the process of withdrawing from the network, so when the terminal initiates a data service activation request, the signal of the low-mode network 1 is poor, resulting in the low-mode network 1 being unable to respond to the data service activation request.

[0156] It should be noted that step S101 is optional and is not a necessary condition for the terminal to execute step S102. The conditions for the terminal to execute step S102 can also include but are not limited to: the terminal determines that the signal strength of the low-mode network 1 is less than a preset threshold.

[0157] S102. The terminal initiates a PS domain deregistration request to the low-mode network 1 and starts timing simultaneously.

[0158] The timing in step S102 may be performed by starting the aforementioned T3321 timer.

[0159] Here, the PS domain deregistration request is the Mo Detach involved in the aforementioned content.

[0160] Generally speaking, low-standard networks (including low-standard network 1) are networks that have been decommissioned (are being decommissioned gradually). At this stage, they can include 2G / 3G networks. In the future, if 4G networks or 5G networks are decommissioned, they can also be called low-standard networks.

[0161] S103. When the preset time is reached and the terminal does not receive a response from the low-standard network 1 to the PS domain deregistration request, the timeout count is increased by 1. The preset time is less than the protocol time.

[0162] When the T3321 timer is started, the protocol time is the time when the T3321 timer times out.

[0163] It should be noted that step S103 is optional, and the protocol time may not be modified, and only the preset number of times may be modified. The Mo Detach process may also be shortened.

[0164] If the timeout times do not reach the preset times, the terminal continues to execute the aforementioned step S102 to initiate a PS domain deregistration request.

[0165] When the number of timeouts reaches a preset number (less than the maximum number of attempts), the terminal executes the following step S104 and no longer waits for the response of the low-standard network 1 to the PS domain deregistration request, directly releases the link and initiates a new search network registration.

[0166] S104. The terminal no longer waits for a response to the PS domain deregistration request, and releases the PS domain link with the low-standard network 1 and initiates a network search.

[0167] S105. When an available network is searched, the terminal initiates a registration request to the available network 1, wherein the registration request includes a PS domain registration request.

[0168] The terminal first scans the available networks around it. When the number of available networks is greater than 2, the terminal can select the best available network (available network 1) from multiple available networks according to a network selection strategy (for example, based on factors such as network priority and network signal strength).

[0169] Then, the terminal initiates a registration request to the available network 1, and the registration (combined attach) request includes at least a PS domain registration request. Alternatively, in addition to the PS domain registration, the registration request may also include a CS domain registration request.

[0170] Among them, the PS domain registration request is used to request registration to the available network 1 and establish a new data connection with the available network 1.

[0171] The CS domain registration request is to request the establishment of a voice call connection, which is used to fallback from the available network 1 to the low-mode network 1 for voice calls.

[0172] This CS domain registration request may carry the context information when the terminal registers to the low-mode network 1. The context usually includes the identification information of the terminal in the low-mode network 1 (such as IMSI, IMEI), access parameters, connection status, etc. By carrying the context information, the terminal can quickly restore the previously established communication state when switching from the connected available network 1 to the low-mode network 1 for voice calls, so as to provide continuous voice call services.

[0173] It should be noted that when the registration request includes the PS domain registration request and the CS domain registration request, this registration request can be called a combined registration request.

[0174] The available network 1 here is usually a high-mode network. Because the performance of the high-mode network is better, when the available networks include the high-mode network and other low-mode networks 1 other than the connected network, the terminal is more likely to choose to camp on the high-mode network through the network selection strategy. The relevant description of the high-mode network can refer to the description of the high-mode network in the foregoing step S6, which will not be elaborated here.

[0175] However, in some scenarios, the available network 1 can also be other low-mode networks other than the connected network. For example, as shown in Figure 8 When the terminal is in the elevator, high-frequency signals (such as 4G / 5G signals) are more easily shielded by materials such as metal than low-frequency signals (2G / 3G signals), and it is difficult to penetrate the elevator car (composed of materials such as metal) into the elevator. Therefore, a 2G network or a 3G network can be covered in the elevator, and the terminal usually connects to the 3G network (because it is better than the 2G network). When there are too many users using the 3G network in the elevator, it will cause the 3G network signal (a kind of low-mode network 1) to become weak and then the 3G network cannot respond to the data service activation request. Therefore, the terminal can execute S102 and step S104 to release the connection with the 3G network and search for a network. At this time, an available 2G network (another low-mode network) can be searched, and then in step S105, the terminal uses the 2G network as the available network 1 and initiates a combined registration request to the 2G network.

[0176] For the scenario where the available network is a high-mode network. After the terminal connects to the 2G network in the elevator. Then refer to Figure 9, after getting out of the elevator, the terminal enters the 4G / 5G network coverage area. At this time, the 2G network is unavailable. At time t, after the number of times the terminal initiates a PS domain deregistration request to the 2G network reaches the preset number of times, if the response to the PS domain deregistration request from the 2G network has not been received yet, the connection with the 2G network is released and network search is performed. For example, if an available 5G network (in a high-generation network) can be searched at this time, then in step S105, the terminal takes the 5G network as the available network 1 and initiates a combined registration request to the 5G network.

[0177] S106. The terminal receives the response to the registration request from the available network 1.

[0178] The response in step S106 indicates that the available network 1 agrees to the combined registration request of the terminal.

[0179] S107. The registration is successful, and the terminal connects to the PS domain of the available network 1.

[0180] Connecting to the PS domain of the available network 1 means that the terminal has established a new data connection with the available network 1.

[0181] The successful combined registration also means that the terminal has established a voice call connection in the available network 1, and this voice call connection is used to fallback from the available network 1 to a lower-generation network 1 for voice calls.

[0182] It should be noted that the lower-generation network can refer to a network that is being phased out. However, the phasing out situation of the lower-generation network is different in different regions. For example, the phasing out situation of the same network can be different in different countries. In some regions, the lower-generation network is being phased out, while in some regions, the lower-generation network has not been phased out. However, the terminal can move, which means that the location where the terminal is located can move from the region where the lower-generation network is being phased out to the region where the lower-generation network has not been phased out.

[0183] Therefore, in another usage scenario (Usage Scenario 2), the network configuration corresponding to the low-mode network in the terminal includes both the modified network configuration involved in Usage Scenario 1 and the network configuration before modification (standard network configuration). In this Usage Scenario 2, when the terminal determines that the low-mode network does not respond to the Nth deregistration request, before the terminal releases the PS domain link with the low-mode network and initiates network search, the terminal will also determine whether the location it is in belongs to a preset area. This preset area is configured to enable the use of the modified network configuration to initiate a deregistration request to the low-mode network. If the terminal determines that its location does not belong to the preset area, the terminal will initiate a deregistration request to the low-mode network N times through the network configuration before modification. Then, after the terminal determines that the low-mode network does not respond to the Nth deregistration request, the terminal will initiate a deregistration request to the low-mode network for the (N + 1)th time. Only when it is determined that the initiated deregistration request is responded, or none of the Z initiated deregistration requests are responded, will the terminal release the PS domain link with the low-mode network and initiate network search. For a detailed description of this process, reference can be made to the description of Figure 10 steps S201 - S208 in the following

[0184] S201. The terminal determines that the low-mode network 1 does not respond to the data service activation request. The new network mode and the original network mode are configured under the low-mode network 1.

[0185] Among them, the new network configuration is the modified network configuration involved above. The original network configuration is the network configuration before modification involved above.

[0186] The process of determining in step S201 that the low-mode network 1 does not respond to the data service activation request is the same as step S101 above. Reference can be made to the description of step S101 above, and details will not be repeated here.

[0187] S202. Determine that the location of the terminal belongs to Area 1.

[0188] In some possible cases, the terminal can determine Area 1 through the area identifier of the connected low-mode network 1.

[0189] S203. Whether the new network configuration is configured to be enabled in Area 1.

[0190] In some possible cases, whether the new network configuration is enabled in different areas is configured into the terminal before leaving the factory. However, subsequently, with the change of the network retirement situation, the situation of whether the new network configuration is enabled in each area can be updated.

[0191] In Area 1, if the low-mode network 1 retires from the network, the new network configuration is configured to be enabled. If there is no network retirement, the original network configuration is configured to be enabled.

[0192] If it is configured to enable the new network configuration in Area 1, the terminal executes the following step S204a to initiate a PS domain deregistration request to the low-mode network 1 through the new network configuration.

[0193] If it is configured to enable the original network configuration in Area 1, the terminal executes the following step S204b to initiate a PS domain deregistration request to the low-mode network 1 through the original network configuration.

[0194] S204a. The terminal initiates a PS domain deregistration request to the low-mode network 1 according to the new network configuration.

[0195] The content involved in step S204a is the same as the content involved in the foregoing steps S102 - S104. The relevant content described above can be referred to and will not be elaborated here.

[0196] S204b. The terminal initiates a PS domain deregistration request to the low-mode network 1 according to the original network configuration.

[0197] The content involved in step S204b is the same as that involved in the foregoing Figure 3 and the content involved. The description of the foregoing Figure 3 and the relevant content can be referred to and will not be elaborated here.

[0198] S205. The terminal releases the PS domain link with the low-mode network 1 and initiates a network search.

[0199] Step S205 is the same as the process in which the terminal releases the PS domain link with the low-mode network 1 and initiates a network search in the foregoing step S104. The relevant content described in step S104 above can be referred to and will not be elaborated here.

[0200] S206. When an available network is searched, the terminal initiates a registration request to the available network 1, and the registration request includes a PS domain registration request.

[0201] S207. The terminal receives the response of the available network 1 to the registration request.

[0202] S208. The terminal successfully registers and connects to the PS domain of the available network 1.

[0203] The content involved in steps S206 - S208 is the same as that in the foregoing steps S105 - S107 respectively. The description of steps S105 - S107 above can be referred to and will not be elaborated here.

[0204] In another usage scenario (Usage Scenario 3), not limited to low-generation networks, new network configurations and original network configurations can be configured for all networks supported by the terminal. In addition to determining whether to use the new network configuration based on whether the network in the area where the terminal is located has withdrawn from the network in Usage Scenario 2, other conditions other than network withdrawal can also be used to determine whether to enable the new network configuration. In Usage Scenario 3, when the network connected by the terminal in the area where the terminal is located (including low-generation networks and high-generation networks) has not withdrawn from the network, other conditions other than network withdrawal are used to determine whether to enable the new network configuration to initiate a PS domain deregistration request to the connected network. When the network connected by the terminal in the area where the terminal is located has withdrawn from the network, the new network configuration is enabled to initiate a PS domain deregistration request to the connected network.

[0205] Among them, the other conditions include: whether the network coverage rate of the network connected by the terminal in the area where it is located is lower than a preset level. For example, the network coverage rate of the network connected by the terminal in the area where it is located is less than the coverage rate of other networks except the connected network. For example, when the connected network is a 4G network or a 5G network, although the 4G network or 5G network has not withdrawn from the network, in some remote areas, the coverage rate of the 4G network or 5G network is low, lower than that of the 2G / 3G network. Therefore, the number of deregistration requests initiated to the 4G network or 5G network can be reduced at this location.

[0206] The exemplary process for the terminal to initiate a Mo detach in Usage Scenario 3 can refer to the following description of steps S301 - step S08.

[0207] S301. The terminal determines that the weak network does not respond to the data service activation request, and both the new network configuration and the original network configuration are configured under this weak network.

[0208] The weak network here refers to the network connected by the terminal and with weak signal. This weak network can be a low-generation network or a high-generation network.

[0209] S302. Determine that the location where the terminal is located belongs to Area 2, and this weak network has not withdrawn from the network in Area 2.

[0210] The method for determining Area 2 is the same as the method for determining Area 1 in the foregoing step S102. Whether different areas have withdrawn from the network is configured into the terminal before leaving the factory. However, it can be updated subsequently as the network withdrawal situation changes.

[0211] It should be noted here that if the weak network has withdrawn from the network in Area 2, the new network protocol can be directly enabled to initiate a PS domain deregistration request to the weak network.

[0212] S303. Whether other conditions for enabling the new network configuration other than network withdrawal are met.

[0213] Here, other conditions for enabling a new network configuration other than network disconnection may include that the network coverage of the weak network in the area where the terminal is located is lower than a preset level. The description of this other condition can refer to the foregoing relevant content and will not be elaborated here. The location of the terminal can be determined by the global positioning system (GPS).

[0214] If other conditions for enabling a new network configuration other than network disconnection are met, the terminal executes the following step S304a to initiate a PS domain deregistration request to the weak network through the new network configuration.

[0215] If other conditions for enabling a new network configuration other than network disconnection are not met, the terminal executes the following step S304b to initiate a PS domain deregistration request to the weak network through the original network configuration.

[0216] S304a. The terminal initiates a PS domain deregistration request to the weak network according to the new network configuration.

[0217] S304b. The terminal initiates a PS domain deregistration request to the weak network according to the original network configuration.

[0218] S305. The terminal releases the PS domain link with the weak network and initiates a network search.

[0219] S306. When an available network is searched, a registration request is initiated to the available network 1, and the combined registration request includes a PS domain registration request.

[0220] When the network mode of the weak network is lower than that of the available network, when an available network is searched, a combined registration request or a PS domain registration request can be initiated to the available network 1. The relevant content of this process can refer to the foregoing step S105 or step S206.

[0221] When the network mode of the weak network is higher than that of the available network, when an available network is searched, a PS domain registration request is initiated to the available network 1. The relevant content about initiating the PS domain registration request can refer to the content related to PS domain registration in the foregoing step S105 or step S206.

[0222] S307. Receive the response of the available network 1 to the registration request.

[0223] S308. The registration is successful, and the terminal connects to the PS domain of the available network 1.

[0224] The content involved in step S304a, step S304b, step S305 - step S308 is respectively similar or the same as that of the foregoing step S204a, step S204b, step S205 - step S208. The description of the foregoing relevant content can be referred to and will not be elaborated here.

[0225] It should be noted that steps S203 in the aforementioned usage scenario 2 and steps S302 and S303 in usage scenario 3 describe the determination method for the terminal to use the new network configuration or the original network configuration. The terminal needs to determine whether to use the new network configuration or the original network configuration in combination with the area where it is located and the nature of the connected network. This includes: when the area where the terminal is located is a preset area and the connected network is a preset network, the terminal uses the new network configuration. When the area where the terminal is located is not a preset area and the connected network is not a preset network, the terminal uses the original network configuration.

[0226] Among them, the preset area is an area where there is a network disconnection situation (for example, areas can be divided according to the network disconnection situations in different countries) or an area where there is no network disconnection situation, but the network coverage is uneven (for example, areas can be divided according to prefecture-level cities smaller than a country, etc.). The preset network may include a network whose network quality in the preset area is lower than a preset condition. The network whose network quality in the preset area is lower than the preset condition includes a network with a network disconnection situation in the preset area, such as the low-standard network involved in usage scenario 2. Or, the network whose network quality in the preset area is lower than the preset condition includes a network whose network coverage in the preset area is lower than a preset level, such as the weak network involved in usage scenario 3.

[0227] It should also be noted that the aforementioned Figure 10 and Figure 11 as described, the determination method for the terminal to determine the new network configuration or the original network configuration can be executed before initiating the PS domain deregistration request. However, it can also be executed after initiating N PS deregistration requests.

[0228] For example, after the terminal connects to a network (Network 1), if it needs to disconnect the data connection with Network 1, it can initiate a deregistration request to Network 1. If the terminal has now initiated N registration requests, when Network 1 does not respond to the Nth deregistration request, the terminal determines that it is in a preset area and Network 1 is a preset network, the terminal releases the PS domain link with Network 1 and initiates a network search. When Network 2 is searched, the terminal initiates a registration request to Network 2 to establish a new data connection. At this time, the previous N deregistration requests were sent based on the original network configuration.

[0229] When Network 1 does not respond to the Nth deregistration request and the terminal is not in a preset area, or when Network 1 does not respond to the Nth deregistration request and Network 1 is not of a preset network standard, the terminal initiates the (N + 1)th deregistration request to Network 1. At this time, the previous N deregistration requests were sent based on the original network configuration.

[0230] It should also be noted that after the terminal sends the i-th deregistration request to Network 1, the T3321 timer is started, where i is greater than or equal to 1 and less than or equal to N;

[0231] When the T3321 timer expires, the terminal has not received a response from Network 1 to the i-th deregistration request, and i is less than N, the terminal sends the (i + 1)-th deregistration request to Network 1.

[0232] When the terminal is in a preset area and Network 1 is of a preset network mode, the preset duration is Duration 1. When the terminal is in the preset area, or when Network 1 is not the preset network, the preset duration is Duration 2; Duration 2 is greater than Duration 1, and Duration 2 is the duration of the T3321 timer specified in the standard protocol.

[0233] The exemplary terminal provided by the embodiments of the present application will be introduced below.

[0234] Figure 12 It is a schematic structural diagram of the terminal provided by the embodiments of the present application.

[0235] The embodiments will be specifically described below taking the terminal as an example. It should be understood that the terminal may have more or fewer components than those Figure 12 shown, may combine two or more components, or may have different component configurations. Figure 12 The various components shown may be implemented in hardware, software, or a combination of hardware and software including one or more signal processing and / or application specific integrated circuits.

[0236] The terminal may include: a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, a headphone interface 170D, a sensor module 180, a key 190, a motor 191, an indicator 192, a camera 193, a display screen 194, and a subscriber identification module (SIM) card interface 195, etc. The sensor module 180 may include a pressure sensor 180A, a gyroscope sensor 180B, a barometric pressure sensor 180C, a magnetic sensor 180D, an acceleration sensor 180E, a distance sensor 180F, a proximity light sensor 180G, a fingerprint sensor 180H, a temperature sensor 180J, a touch sensor 180K, an ambient light sensor 180L, a bone conduction sensor 180M, etc. Among them, the processor may include an application processor (AP) and a modem processor (Modem, also known as a baseband processor).

[0237] The foregoing original network configuration or new network configuration may be recorded in the modem processor.

[0238] It can be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the terminal. In other embodiments of the present application, the terminal may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0239] In the embodiments of the present application, the processor 110 may call computer instructions stored in the internal memory 121 to cause the terminal to execute the methods in the embodiments of the present application.

[0240] The present application also provides a chip system, which includes at least one processor for implementing the functions involved in the methods executed by the terminal in any one of the foregoing embodiments.

[0241] In a possible design, the chip system further includes a memory for storing program instructions and data, and the memory is located inside or outside the processor.

[0242] The chip system may be composed of chips or may include chips and other discrete devices.

[0243] Optionally, there may be one or more processors in the chip system. The processor may be implemented by hardware or by software. When implemented by hardware, the processor may be a logic circuit, an integrated circuit, etc. When implemented by software, the processor may be a general-purpose processor that implements its functions by reading software code stored in a memory.

[0244] Optionally, there may also be one or more memories in the chip system. The memory may be integrated with the processor or may be separately provided from the processor. The embodiments of the present application do not limit this.

[0245] Exemplarily, the memory may be a non-transitory processor, such as a read-only memory (ROM). It may be integrated with the processor on the same chip or may be separately provided on different chips. The embodiments of the present application do not specifically limit the type of the memory and the setting manner of the memory and the processor.

[0246] Exemplarily, the chip system may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), a central processing unit (CPU), a network processor (NP), a digital signal processing circuit (DSP), a microcontroller unit (MCU), a programmable logic device (PLD), or other integrated chips.

[0247] The present application also provides a computer program product, which includes a computer program (which may also be referred to as code or instruction). When the computer program is run, the computer is caused to execute the method executed by the terminal in any one of the above embodiments.

[0248] The present application also provides a computer-readable storage medium, which stores a computer program (which may also be referred to as code or instruction). When the computer program is run, the computer is caused to execute the method executed by the terminal in any one of the above embodiments.

[0249] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the various embodiments of the present application.

[0250] In the above embodiments, depending on the context, the term "when..." can be interpreted to mean "if...", or "after...", or "in response to determining...", or "in response to detecting...". Similarly, depending on the context, the phrase "when determining..." or "if detecting (the stated condition or event)" can be interpreted to mean "if determining...", or "in response to determining...", or "when detecting (the stated condition or event)", or "in response to detecting (the stated condition or event)".

[0251] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. As used in the specification and claims of the present application, the singular forms "a", "an", "the", "above", "said", "this" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term " / and" used in the present application refers to and includes any or all possible combinations of one or more of the listed items. The symbol " / " used in the present application can mean " / and".

[0252] The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0253] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line) or wirelessly (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more integrated available media. The available medium may be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a solid-state drive), etc.

[0254] Those of ordinary skill in the art can understand that all or part of the processes in the above method embodiments can be completed by a computer program instructing relevant hardware. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the above method embodiments. The foregoing storage medium includes various media that can store program codes, such as ROM or random access memory RAM, magnetic disks, or optical discs.

Claims

1. A network registration method, characterized in that, Including: The terminal sends an Nth deregistration request to the first network, and the deregistration request is used to disconnect the first data connection with the first network; In the case that the first network does not respond to the Nth deregistration request, the terminal is in a preset area, and the first network is a preset network, the terminal releases the packet switched (PS) domain link with the first network and initiates network search; wherein, the PS domain link is used to implement the first data connection; the preset network includes a network with network quality lower than a preset condition in the preset area; In the case of searching for a second network, the terminal sends a registration request to the second network, and the registration request is used to establish a second data connection with the second network; Wherein, N is a positive integer less than Z, and Z is the maximum number of attempts specified in the standard protocol for the terminal to send a deregistration request to the first network. The standard protocol stipulates that the conditions for the terminal to release the PS domain link with the first network include: the deregistration request initiated by the terminal is responded to by the first network, or none of the Z deregistration requests initiated by the terminal are responded to.

2. The method according to claim 1, characterized in that The network with network quality lower than the preset condition in the preset area includes a network with a network withdrawal situation in the preset area, or the network with network quality lower than the preset condition in the preset area includes a network with a network coverage range lower than a preset level in the preset area.

3. According to claim 1 or 2, characterized in that, The method further includes: In the case that the first network does not respond to the Nth deregistration request and the terminal is not in the preset area, or in the case that the first network does not respond to the Nth deregistration request and the first network is not of the preset network type, the terminal sends an (N + 1)th deregistration request to the first network.

4. The method according to any one of claims 1 to 3, characterized in that The method further includes: After the terminal sends the ith deregistration request to the first network, it starts the T3321 timer, where i is greater than or equal to 1 and less than or equal to N; In the case that the T3321 timer times out for a preset duration, the terminal does not receive a response from the first network to the ith deregistration request, and i is less than N, the terminal sends an (i + 1)th deregistration request to the first network; In the case that the terminal is in the preset area and the first network is of the preset network type, the preset duration is the first duration; in the case that the terminal is not in the preset area, or in the case that the first network is not the preset network, the preset duration is the second duration; the second duration is greater than the first duration; the second duration is the duration of the T3321 timer specified in the standard protocol.

5. The method according to any one of claims 1 to 4, characterized in that The network type of the second network is higher than that of the first network, or the coverage range of the second network in the preset area is greater than that of the first network in the preset area.

6. The method according to claim 4, characterized in that, The second duration is 15 seconds, and the first duration is 5 seconds.

7. The method according to any one of claims 1-6, characterized in that, Z is equal to 5, and N is equal to 1.

8. The method according to any one of claims 1 to 7, characterized in that, The method further includes: Before the terminal first sends a deregistration request to the first network, the terminal determines that the activation of the data service fails.

9. The method according to any one of claims 1-8, characterized in that, The registration request is further used to establish a voice call connection; the voice call connection is used to fallback from the second network to the first network for voice calls.

10. The method according to any one of claims 1-9, wherein the first network is a 2G or 3G network, and the second network is a 4G or 5G network; when the first network is a 2G network, the network mode of the first network includes the Global System for Mobile Communications (GSM) network mode; when the first network is a 3G network, the network mode of the first network includes the Wideband Code Division Multiple Access (WCDMA) network mode.

11. A terminal, characterized in that, comprising: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to cause the terminal to execute the method according to any one of claims 1-10.

12. A chip system, the chip system being applied to a terminal, characterized in that, The chip system includes one or more processors, and the processors are used to call computer instructions to cause the terminal to execute the method according to any one of claims 1-10.

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