CN116709293B

CN116709293B - Network selection method and terminal

Info

Publication number: CN116709293B
Application number: CN202310611488.0A
Authority: CN
Inventors: 张涵; 丁明
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2023-05-25
Filing date: 2023-05-25
Publication date: 2024-05-17
Anticipated expiration: 2043-05-25
Also published as: CN116709293A

Abstract

The application provides a network selection method and a terminal, and relates to the technical field of communication, wherein the method comprises the following steps: in the scene that the RPLMN does not exist in the PLMN list of the terminal but the first PLMN exists, and in the situation that the system information corresponding to the first PLMN does not exist in the first network system, the terminal selects the first PLMN and searches the frequency point corresponding to the cell covered by the first network system; when the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card, so that the user does not need to replace the SIM card, the terminal can rapidly reside in the cell corresponding to the high system through the SIM card, and the user experience is improved.

Description

Network selection method and terminal

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a network selection method and a terminal.

Background

Public land mobile networks (public land mobile network, PLMNs) are networks established and operated by governments or operators approved by them to provide land mobile services to the public. The PLMN is identified by a mobile country code (mobile country code, MCC) and a mobile network code (mobile network code, MNC).

To obtain network services such as voice, data, multimedia, etc., the terminal first needs to select a suitable PLMN, search cells under the PLMN, find available cells, reside on a subscriber identity module (subscriber identification module, SIM) card, and initiate network registration. The third generation partnership project (the 3rd generation partnership project,3GPP) TS23.122 protocol specifies that the terminal selects an appropriate PLMN in the order of registering public land mobile network (REGISTERED PLMN, RPLMN), home Public Land Mobile Network (HPLMN), user controlled public land mobile network (UPLMN), operator controlled public land mobile network (operator controlled PLMN, OPLMN) and other PLMN (other PLMN) when automatically selecting a network, the terminal camps on a SIM card and registers with the network.

In the related art, if the terminal adopts the mode of automatically selecting the network when the RPLMN does not exist, the terminal sequentially selects a suitable PLMN according to the sequence of HPLMN, UPLMN, OPLMN and other PLMNs, and resides and registers the network through the SIM card. However, for the non-upgraded SIM cards, the account numbers of the non-upgraded SIM cards have the authority to access the high-system network, the terminal can reside in the cell corresponding to the low-system network through the SIM card, and then the terminal can only reside in the cell corresponding to the high-system through the SIM card in a network configuration mode such as reselection/switching/redirection.

Disclosure of Invention

The embodiment of the application provides a network selection method and a terminal, which do not need a user to replace an SIM card, so that the terminal can quickly reside in a cell corresponding to a high system through the SIM card, and the user experience is improved.

The embodiment of the application adopts the following technical scheme:

In a first aspect, a network selection method is provided, and the network selection method is applied to a terminal including a first SIM card, wherein the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority to access the first network system; the method comprises the following steps:

In a scene that an RPLMN does not exist in a PLMN list of the terminal but a first PLMN exists, the terminal determines that the system information corresponding to the first PLMN does not exist in a first network system; the first PLMN is an HPLMN; or the first PLMN is an OPLMN.

Under the condition that the system information corresponding to the first PLMN does not exist in the first network system, the terminal selects the first PLMN and searches the frequency point corresponding to the cell covered by the first network system; when the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card.

Based on the above scheme, in the present application, in the scenario that there is no RPLMN in the PLMN list of the terminal, but there is a first PLMN, and in the case that the system information corresponding to the first PLMN does not have the first network system, the terminal selects the first PLMN, and searches the frequency point corresponding to the cell covered by the first network system; because the terminal supports access to the first network system, and the account corresponding to the first SIM card has the authority to access the first network system, when the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card, so that the situation that a user does not need to replace the first SIM card can be realized, the terminal can rapidly reside in the cell corresponding to the high system through the first SIM card, and the user experience is improved.

Optionally, the first network system is a high system, for example, the first network system is a 5G system (or referred to as NR system); or the first network system is a 4G system (or LTE system).

In one possible implementation of the first aspect, in a scenario in which the RPLMN is not present in the PLMN list of the terminal and the HPLMN is stored, the first PLMN is the HPLMN; or in the scenario that the RPLMN and the HPLMN are not present in the PLMN list of the terminal, but the OPLMN is present, the first PLMN is the OPLMN.

Optionally, when the first PLMN is an HPLMN, the terminal selects the HPLMN after powering on, and under the HPLMN, the terminal searches a frequency point corresponding to a cell covered by the first network system. When the first PLMN is OPLMN, the terminal selects OPLMN after starting up, and under the OPLMN, the terminal searches a frequency point corresponding to a cell covered by the first network system.

In one possible implementation of the first aspect, the RPLMN is not present in the PLMN list of the terminal, but the scenario in which the first PLMN is present includes, but is not limited to: the method comprises the steps of first starting after the operating system of the terminal is automatically upgraded, first starting after the terminal leaves a factory, first starting after the terminal is restored to factory setting, or first starting after the operating system of the terminal is reinstalled.

Optionally, when the first PLMN is an OPLMN, no RPLMN exists in the PLMN list of the terminal, but the scenario where the first PLMN exists refers to: the RPLMN and HPLMN are not present in the PLMN list of the terminal, but the OPLMN is present. Wherein, there is no RPLMN and HPLMN in the PLMN list of the terminal, but the scenario where there is an OPLMN includes, but is not limited to: a terminal losing network coverage or the terminal being in a roaming state, etc.

In a possible implementation manner of the first aspect, the selecting, by the terminal, a first PLMN, searching a frequency point corresponding to a cell covered by the first network system includes: the terminal adds information of a first network system into system information corresponding to a first PLMN; then, the terminal selects a first PLMN and searches a frequency point corresponding to a cell covered by a first network system.

Therefore, the terminal adds the information of the first network system in the system information corresponding to the first PLMN, so that the terminal selects the first PLMN and can search the frequency point corresponding to the cell covered by the first network system, the user does not need to replace the first SIM card, the terminal can quickly reside in the cell corresponding to the high system through the first SIM card, and the user experience is improved.

Optionally, when the terminal is powered on, the card file of the first SIM card is first read, where the card file of the first SIM card includes information about the PLMN (including, for example, an RPLMN file, an HPLMN file, or an OPLMN file). After the terminal reads the card file of the first SIM card, the terminal copies the card file of the first SIM card to a PLMN list maintained in the Modem, and then the terminal selects a proper PLMN to search cells according to the priority order of the PLMN list.

Optionally, in the process of reading the card file of the first SIM card, the terminal adds information of the first network system to the system information corresponding to the first PLMN. Or alternatively; in the process that the terminal copies the card file of the first SIM card to the Modem, the information of the first network system is added in the system information corresponding to the first PLMN.

In a possible implementation of the first aspect, the terminal includes a Modem; the terminal adds information of a first network system in system information corresponding to a first PLMN, and the method comprises the following steps: the terminal reads a first card file of the first SIM card, modifies the first card file of the first SIM card, and adds information of a first network system into system information corresponding to the first PLMN to obtain a second card file of the first SIM card.

Further, the terminal selects a first PLMN, searches a frequency point corresponding to a cell covered by a first network system, and includes: the terminal copies a second card file of the first SIM card into the Modem; and the terminal selects a first PLMN through the Modem and searches a frequency point corresponding to a cell covered by the first network system.

In this way, the terminal modifies the first card file of the first SIM card, adds the information of the first network system in the system information corresponding to the first PLMN to obtain the second card file of the first SIM card, so that after copying the second card file of the first SIM card to the Modem, the terminal can select the first PLMN through the Modem to search the frequency point corresponding to the cell covered by the first network system, thereby realizing that the first SIM card is not required to be replaced by a user, enabling the terminal to rapidly reside in the cell corresponding to the high system through the first SIM card, and improving the user experience.

In one possible implementation of the first aspect, modifying the first card file of the first SIM card includes: and modifying the first card file of the first SIM card in the process of reading the first card file of the first SIM card by the terminal.

In one possible implementation of the first aspect, in a process of reading a first card file of a first SIM card by a terminal, modifying the first card file of the first SIM card, adding information of a first network system to system information corresponding to a first PLMN, to obtain a second card file of the first SIM card, including: in the process that the terminal reads the first card file of the first SIM card, a switch control item related to modifying the first card file of the first SIM card is in an enabling state; and under the condition that the switch control item is in an enabling state, the terminal modifies a first card file of the first SIM card, and adds information of a first network system into system information corresponding to the first PLMN to obtain a second card file of the first SIM card.

In the scheme, the switch control item related to the first card file for modifying the first SIM card is arranged, and the reliability of modifying the first card file of the first SIM card can be improved under the condition that the switch control item is in an enabled state.

Optionally, after the terminal reads the first card file of the first SIM card, a switch control item associated with modifying the first card file of the first SIM card is in an off state. In this way, device power consumption may be reduced.

In a possible implementation manner of the first aspect, the selecting, by the terminal, a first PLMN, searching a frequency point corresponding to a cell covered by the first network system includes: after the terminal selects a first PLMN, a first network searching list is generated; the first network searching list comprises system information corresponding to a first PLMN; the terminal adds information of a first network system into the first network searching list to obtain a second network searching list; and the terminal searches the frequency point corresponding to the cell covered by the first network system according to the second network searching list.

In the scheme, after selecting the first PLMN, the terminal can also add information of a first network system into a first network searching list generated by the terminal to obtain a second network searching list; and then, the terminal can search the frequency point corresponding to the cell covered by the first network system according to the second network searching list, so that the situation that the user does not need to replace the first SIM card is realized, the terminal can quickly reside in the cell corresponding to the high system through the first SIM card, and the user experience is improved.

In a second aspect, a terminal is provided, where the terminal has a function of implementing the network selection method in any one of the first aspects, where the function may be implemented by hardware, or may be implemented by executing corresponding software by hardware, where the hardware or software includes one or more modules corresponding to the above functions.

In a third aspect, a terminal is provided, the terminal comprising a first SIM card; the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority for accessing the first network system; the terminal further comprises: a memory and one or more processors; the memory is configured to store computer-executable instructions that, when executed by the terminal, cause the terminal to perform the network selection method according to any one of the first aspect.

In a fourth aspect, a terminal is provided; the terminal comprises a first SIM card; the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority for accessing the first network system; the terminal further comprises: a processor; the processor is coupled to the memory and executes the network selection method according to any one of the above first aspects according to the instructions after reading the instructions in the memory.

In a fifth aspect, a chip system is provided and applied to a terminal, the terminal comprises a first SIM card, the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority to access the first network system; the chip system comprises a processor and an interface, wherein the interface is used for receiving instructions and transmitting the instructions to at least one processor; at least one processor executes the instructions to cause the terminal to perform the network selection method according to any one of the first aspects.

In a sixth aspect, there is provided a computer readable storage medium having instructions stored therein which, when run on a computer, cause the computer to perform the network selection method of any one of the first aspects above.

In a seventh aspect, a computer program product comprising instructions is provided which, when run on a computer, causes the computer to perform the method of screening according to any one of the first aspects above.

The technical effects of any one of the design manners of the second aspect to the seventh aspect may be referred to the technical effects of the different design manners of the first aspect, and will not be repeated here.

Drawings

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

Fig. 2 is a schematic diagram of a PLMN list according to an embodiment of the present application;

Fig. 3 is a schematic flow chart of a network selection method according to an embodiment of the present application;

Fig. 4 is a second schematic flow chart of a network selection method according to an embodiment of the present application;

fig. 5 is a schematic flow chart III of a network selection method according to an embodiment of the present application;

Fig. 6 is a flow chart diagram of a network selection method according to an embodiment of the present application;

Fig. 7 is a flow chart diagram of a network selection method according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a terminal according to an embodiment of the present application;

Fig. 9 is a schematic structural diagram of a chip system according to an embodiment of the present application.

Detailed Description

In the description of the embodiments of the present application, unless otherwise indicated, "/" means or, for example, a/B may represent a or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: three cases of A alone, A and B together, and B alone exist.

The following terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the embodiments of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In embodiments of the application, words such as "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g." in an embodiment should not be taken as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

For ease of understanding, technical terms related to the embodiments of the present application will be explained first.

1) A PLMN is understood to be an Identification (ID) of an operator, with different PLMN values corresponding to different operators. The terminal may select a corresponding operator network (i.e., PLMN) according to the subscription information.

2) The HPLMN is the PLMN of the operator to which the SIM card of the terminal belongs. If the operator to which the SIM card of the terminal belongs is operator a, the HPLMN of the terminal is a PLMN of operator a.

3) And the UPLMN refers to PLMN selected by the terminal when the user manually selects the network, and the PLMN is stored in the SIM card of the terminal.

4) The OPLMN refers to the PLMN of the operator who signed a roaming agreement with the operator, into which the operator can write the OPLMN when generating the SIM card.

5) The RPLMN is a PLMN that the terminal successfully registered, such as a PLMN that the terminal registered prior to last shutdown or off-network. Such as: and if the PLMN registered before the last shutdown of the terminal is the PLMN of the operator B, the RPLMN of the terminal is the PLMN of the operator B. The RPLMN and the HPLMN of the terminal may be the same or different. Such as: the HPLMN of the terminal is a PLMN of the operator a, and the PLMN registered before the last shutdown of the terminal is also a PLMN of the operator a, and the RPLMN of the terminal is also a PLMN of the operator a, i.e. the RPLMN of the terminal is the same as the HPLMN.

6) An Equivalent PLMN (EPLMN) is a PLMN that is located in the same position as the PLMN currently selected by the terminal. The EPLMN is a PLMN sent by network equipment received by the terminal. When the terminal receives PLMN (namely EPLMN) sent by the network equipment, the terminal stores the EPLMN information in a local PLMN list, and if the terminal selects EPLMN during network searching, the terminal performs cell searching under the EPLMN.

The following describes the technical scheme of the embodiment of the present application in detail with reference to the drawings.

The technical solution of the embodiment of the present application may be applied to various communication systems, for example, a 4G mobile communication system (such as a long term evolution (long term evolution, LTE) system), a worldwide interoperability for microwave access (worldwide interoperability for microwave access, wiMAX) communication system, a 5G communication system (such as a New Radio (NR) system), and a future communication system (such as a sixth generation (6th generation,6G) mobile communication system).

Wherein the communication system may include a terminal, a network device, and the like. A terminal may also be called a terminal device (terminal equipment), a User Equipment (UE), a mobile station, a mobile terminal, etc. The terminal in the embodiment of the application can be a communication device capable of installing the SIM card. For example, the terminal may be a cell phone, a smart watch, a smart bracelet, a tablet, a notebook, a palm, a mobile internet device (mobile INTERNET DEVICE, MID), a Virtual Reality (VR) device, an enhanced display (augmented reality, AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned (SELF DRIVING), a wireless terminal in teleoperation (remote medical surgery), a wireless terminal in smart grid (SMART GRID), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (SMART CITY), or a wireless terminal in smart home (smart home), etc. The embodiment of the application does not limit the specific technology and the specific equipment form adopted by the terminal.

The network device is an access device for a terminal to access to a communication system in a wireless manner, and may be an evolved Node B (eNB), a radio network controller (radio network controller, RNC), a Node B (Node B, NB), a base station controller (base station controller, BSC), a base transceiver station (base transceiver station, BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a baseband unit (BBU), a radio relay Node, a radio backhaul Node, a transmission point (transmission and reception point, TRP, or transmission, TP), and the like. It may also be a 5G (such as a gNB in NR or a transmission point (TRP or TP)), one or a group (including a plurality of antenna panels) of base stations in a 5G system, or may also be a network node (such as a baseband unit BBU, or a Distributed Unit (DU)) constituting the gNB or the transmission point, a Road Side Unit (RSU) having a base station function, or the like. The embodiment of the application does not limit the specific technology and the specific equipment form adopted by the network equipment.

Referring to fig. 1, a schematic diagram of a communication system is shown. As shown in fig. 1, in the communication system, a terminal communicates with other devices through a wireless network including a radio access network (radio access network, RAN) and a Core Network (CN). The RAN is used for accessing the terminal to the wireless network, and the CN is used for managing the terminal and providing a gateway for communicating with an external network.

Taking the example of a wireless network as a 5G network, the wireless network may include network devices (e.g., RAN devices) responsible for the transmission of data over the wireless interface. The core network may include signaling plane network elements, such as access and mobility management functions (ACCESS AND mobility management function, AMF) and session management functions (session management function, SMF), responsible for setting up data transmission channels. Wherein, SMF is mainly responsible for session management, and AMF is mainly responsible for user management. The core network may also include data plane network elements, such as user plane functions (user plane function, UPF), primarily responsible for data forwarding.

Referring to fig. 1, when the terminal is powered on or off, a suitable PLMN is first selected, and then a cell of the PLMN is searched. After searching available cells, the terminal accesses to a wireless network covered by the cells through network equipment and resides in the cells through the SIM card. The terminal may then communicate wirelessly (e.g., to obtain network services such as voice, data, and multimedia) with the core network via the network device.

For example, after the terminal is powered on, a Network Access Server (NAS) may initiate a request for selecting a PLMN, so as to select a suitable PLMN under which to perform a cell search. If the terminal finds an available cell, the terminal performs residence and initiates network registration.

The process of selecting a PLMN by a terminal and performing cell search under the PLMN may be referred to as a network selection process. The network selection process of the terminal can comprise automatic network selection and manual network selection.

The manual network selection refers to that when a terminal is started or disconnected, the non-access layer instructs the access layer to search all PLMNs, and then the access layer reports the searched information of all PLMNs to the non-access layer, and a user manually operates to select one PLIM. And then, the terminal searches cells under the PLMN, and if the terminal finds an available cell, the terminal camps and initiates network registration.

Unlike manual network selection, automatic network selection refers to that when a terminal is powered on or off, a suitable PLMN is automatically selected according to the order of the PLMN list in the existing protocol specification. The subsequent search process is the same as manual web selection, and reference is made to the above description.

For example, when the terminal performs the automatic network selection procedure, a PLMN list is required to be maintained in the terminal according to the specification about the automatic network selection procedure in the 3gpp ts23.122 protocol, where the PLMN list includes multiple PLMNs of different types, and the priority levels of the PLMNs of different types are different. For example, as shown in fig. 2, in order of priority levels of PLMNs from high priority level to low priority level, an RPLMN (or EPLMN), an HPLMN (or EHPLMN), an OPLMN, other PLMNs with high quality signals, and other PLMNs with secondary quality signals are sequentially included in a PLMN list maintained in the terminal.

It should be noted that, because the UPLMN is a PLMN selected by the terminal when performing manual network selection, in the embodiment of the present application, the UPLMN may not be selected when the terminal is performing an automatic network selection procedure. The UPLMN is thus not illustrated in fig. 2.

In general, the information of the PLMN is stored in the form of a database in an encrypted file system (ENCRYPTING FILE SYSTEM, EFS) partition of the SIM card, and when the terminal is powered on, the terminal can read the information of the PLMN from the EFS partition and store the information of the PLMN in a local PLMN list.

Illustratively, the terminal reads RPLMNACT (i.e., RPLMN file), HPLMNACT (i.e., HPLMN file), OPLMNACT (i.e., OPLMN file) from the EFS partition in order of priority of the PLMNs, and stores the PLMN files in the local PLMN list. Then, the terminal selects a suitable PLMN according to the priority order of the PLMN list, and performs cell search under the PLMN.

The information of the PLMN of each file in the RPLMN file, the HPLMN file, and the OPLMN file includes MCC, MNC, and system information, where the system information is a radio access technology (radio access technology, RAT) supported by the PLMN. RATs include, but are not limited to: global mobile communications (global system of mobile communication, GSM), code division multiple access (code division multiple access, CDMA), wideband code division multiple access (wideband code division multiple access, WCDMA), universal mobile telecommunications system (universal mobile telecommunication system, UMTS), long term evolution (long term evolution, LTE), and New Radio (NR), among others.

For example, table 1 is information of PLMNs corresponding to PLMNs with different priority levels in a PLMN list maintained by the terminal.

TABLE 1

PLMN list	MCC	MNC	RAT
				RPLMN	460	01	GSM、UMTS、LTE、NR
HPLMN	460	01	GSM、UMTS、LTE、NR
				OPLMN	460	01	GSM、UMTS、LTE、NR

As shown in table 1, MCC generally contains three digits for uniquely identifying the country code in which the terminal is located, such as chinese with 460; the MNC generally uses two digits (or three digits) to identify the operator selected by the terminal, and MNCs corresponding to different operators are different.

In combination with table 1, after the terminal is powered on, the terminal will first select the RPLMN and search for a cell under the RPLMN. As shown in table 1 above, when the terminal searches for a cell under the RPLMN, the terminal supports access to a plurality of network systems (e.g., support GSM, UMTS, LTE, NR, etc.). On the basis, the terminal can search cells under the corresponding network system according to the sequence of the signal quality from high to low corresponding to the network system. The signal quality corresponding to the network system is sequentially from high to low: NR > LTE > UMTS > GSM.

For example, the terminal searching for a cell under the RPLMN includes: and the terminal firstly performs cell search under an NR system under the RPLMN. If no cell is searched in NR system, then searching cell in LTE system. If no cell is searched in LTE system, then searching cell in UMTS system. If no cell is searched in the UMTS system, then searching the cell in the GSM system.

In addition, one PLMN corresponds to one frequency band, each frequency band corresponds to a plurality of frequency points, and different frequency points can be understood as frequency points corresponding to cells covered by different network systems. Thus, the terminal searching for a cell under the RPLMN further comprises: and the terminal searches the frequency points in the frequency band corresponding to the RPLMN under the RPLMN. If the terminal searches the frequency point corresponding to the cell covered by the NR system in the frequency band corresponding to the RPLMN under the RPLMN.

In some embodiments, in a scenario where no RPLMN exists in the PLMN list maintained in the terminal, the terminal selects the HPLMN according to the priority order of the PLMN list, and performs cell search under the HPLM. Or under the scene that the RPLMN and the HPLM do not exist in the PLMN list maintained in the terminal, the terminal selects the OPLMN according to the priority order of the PLMN list and performs cell search under the OPLMN. The specific process of searching for a cell may refer to the above description, and will not be repeated here.

It should be noted that, in the embodiment of the present application, the absence of the RPLMN in the PLMN list maintained in the terminal may be understood as: the PLMN list maintained in the terminal does not include information of the RPLMN. For example, when the terminal is powered on, the RPLMN file is not read from the SIM card.

Exemplary scenarios in which no RPLMN is present in the PLMN list maintained in the terminal include, but are not limited to: the method comprises the steps of first starting after the operating system of the terminal is automatically upgraded, first starting after the terminal leaves a factory, first starting after the terminal is restored to factory setting, or first starting after the operating system of the terminal is reinstalled.

In addition, the scenario in which the HPLMN does not exist in the PLMN list maintained in the terminal includes: the terminal loses network coverage or the terminal is in a roaming state.

Based on the fact that the RPLMN is not present in the PLMN list maintained in the terminal, for some users holding the terminal, the SIM card used by the user may not be updated (for example, the SIM card is a 2G or 3G card), so that the LTE standard and/or the NR standard are not present in the standard information of the HPLMN or the OPLMN in the SIM card, which can be understood as: the SIM card does not support to reside in a cell corresponding to the LTE system or the NR system, namely the SIM card does not have the capacity of the LTE system or the NR system.

However, the account corresponding to the SIM card has the authority to access the LTE standard and/or the NR standard, which can be understood as follows: the user holding the SIM card purchases a 4G or 5G mobile package. In this case, since the LTE system and/or the NR system does not exist in the HPLMN or OPLMN system information of the SIM card in the terminal, when the terminal executes the automatic network selection procedure, the SIM card in the terminal first resides in a cell corresponding to a low system such as the GSM system or the UMTS system. After that, the terminal can only reside in the cell corresponding to the high system such as the LTE system or the NR system through the network configuration mode such as reselection/switching/redirection, so that the SIM card in the terminal cannot quickly reside in the cell corresponding to the high system, and the user experience is affected.

For the above-described terminal, in the PLMN list maintained in the terminal, the information of PLMNs corresponding to PLMNs with different priority levels may be as shown in table 2.

TABLE 2

PLMN list	MCC	MNC	RAT
				HPLMN	460	01	GSM、UMTS
OPLMN	460	01	GSM、UMTS

As shown in table 2, after powering on, the terminal first selects the HPLMN and searches for a cell under the HPLMN. As shown in table 2 above, when the terminal searches for a cell under the HPLMN, the SIM card in the terminal supports access to multiple network systems (e.g., support access to GSM and UMTS). On the basis, the terminal searches cells under the corresponding network system according to the sequence of the signal quality from high to low corresponding to the network system. The network system sequence is from high to low: UMTS > GSM.

For example, the terminal searching for a cell under the HPLMN includes: under HPLMN, the terminal first performs cell search under UMTS system. If no cell is searched in the UMTS system, then searching the cell in the GSM system.

It can be seen that, in the scenario that the RPLMN does not exist in the PLMN list maintained by the terminal, if the terminal performs cell search under the HPLMN or the OPLMN, the terminal may reside in a cell corresponding to a UMTS standard or a low standard such as GSM through the SIM card. After that, the terminal can only reside in the cell corresponding to the high system such as the LTE system or the NR system through the network configuration manner such as reselection/switching/redirection, which results in that the SIM card in the terminal cannot quickly reside in the cell corresponding to the high system, resulting in poor user experience. In other words, in the above scenario, how to enable the SIM card in the terminal to quickly reside in the cell corresponding to the high system after the terminal is powered on is a problem to be solved currently.

Based on the analysis, the embodiment of the application provides a network selection method, under the scene, a user can quickly reside the SIM card in the terminal in a cell corresponding to a high system after the terminal is started on the basis of not upgrading the SIM card, and the user experience is improved.

The method provided by the embodiment of the application will be explained in the following with reference to the attached drawings. It is to be understood that, in the embodiments of the present application, the execution subject may perform some or all of the steps in the embodiments of the present application, these steps or operations are only examples, and the embodiments of the present application may also perform other operations or variations of the various operations. Furthermore, the various steps may be performed in a different order presented in accordance with embodiments of the application, and it is possible that not all of the operations in the embodiments of the application may be performed.

It should be noted that, in the following embodiments of the present application, the names of the messages between the functions or entities or the names of the information in the messages are only an example, and may be other names in specific implementations, which are not limited in particular by the embodiments of the present application.

As shown in fig. 3, the network selecting method provided by the embodiment of the application is applied to a terminal including a first SIM card, the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority to access the first network system; the network selection method can comprise the following steps:

S101, the terminal executes an automatic network selection process after being started.

S102, the RPLMN exists in a PLMN list in the terminal, and the terminal performs cell search according to the system information corresponding to the RPLMN.

Illustratively, the presence of an RPLMN in the PLMN list in the terminal may be understood as: the first SIM in the terminal holds the PLMN that the terminal was last successfully registered. Thus, when the terminal is powered on, the RPLMN file (i.e., RPLMNACT) may be read from the card file of the first SIM card.

Exemplary scenarios in which there is an RPLMN in the PLMN list in the terminal include, but are not limited to: the terminal is powered off and powered on at the same place, the terminal is powered on for the first time after the operating system is automatically upgraded, the terminal is powered on for the first time after leaving the factory, the terminal is powered on for the first time after restoring the factory setting, or the operating system of the terminal is powered on for the first time after being reinstalled.

The system information corresponding to the RPLMN includes a plurality of network systems supported by the terminal to access the RPLMN.

It should be noted that, the specific implementation process of the terminal for performing the cell search according to the system information corresponding to the RPLMN may refer to the above table 1 and description, which are not repeated herein.

S103, the RPLMN does not exist in the PLMN list in the terminal, but the first PLMN exists, and the terminal determines that the system information corresponding to the first PLMN does not exist in the first network system.

Wherein the first PLMN is an HPLMN; or the first PLMN is an OPLMN.

It should be noted that, the RPLMN is not present in the PLMN list in the terminal, but the scenario in which the first PLMN is present may refer to the illustration in the above embodiment, which is not described herein again.

In addition, the absence of the first network system in the system information corresponding to the first PLMN may be understood as: the system information corresponding to the first PLMN does not include information of the first network system (such as information of NR system or information of LTE system).

Note that S102 and S103 are two parallel steps, and in the embodiment of the present application, the terminal does not execute S103 in the case of executing S102. Accordingly, the terminal does not perform S102 in the case of performing S103.

S104, under the condition that the system information corresponding to the first PLMN does not have the first network system, the terminal selects the first PLMN and searches the frequency point corresponding to the cell covered by the first network system.

It can be appreciated that, since the RPLMN is not present in the PLMN list of the terminal, the terminal will first select the first PLMN for cell search after power-on.

In the embodiment of the application, even if the system information corresponding to the first PLMN does not have the first network system, the terminal searches the frequency point corresponding to the cell of the first network system. Thus, when the terminal searches the cell covered by the first network system, the terminal can reside in the cell corresponding to the first network system through the first SIM card.

Illustratively, when the first PLMN is an HPLMN, the terminal selects the HPLMN for cell search. And searching a frequency point corresponding to the cell covered by the first network system by the terminal under the HPLMN. Or when the first PLMN is OPLMN, the terminal selects OPLMN to search the cell. And searching a frequency point corresponding to the cell covered by the first network system by the terminal under the OPLMN.

S105, when the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card.

In S105, when the terminal searches for a cell covered by the first network system, the terminal initiates network registration to the network (such as the network device and the core network shown in fig. 1) through the first SIM card, so as to reside in the cell corresponding to the first network system through the first SIM card.

Based on the scheme, in the scene that the RPLMN does not exist in the PLMN list of the terminal, but the first PLMN exists, the terminal firstly selects a first PLIMN, and under the first PLMN, cell searching is carried out according to the system information corresponding to the first PLMN; and under the condition that the system information corresponding to the first PLMN does not exist in the first network system, the terminal can search frequency points corresponding to the cells covered by the first network system in the frequency band corresponding to the first PLMN, namely, the terminal performs cell search under the first network system. And then, when the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card. Therefore, the first SIM card in the terminal can be quickly resided in the cell corresponding to the first network system on the premise of not upgrading the first SIM card.

In addition, the terminal supports access to the first network system, and the account corresponding to the first SIM card in the terminal has the authority to access the first network system, so that the first SIM card is forced to reside in a cell corresponding to the first network system on the premise that the first SIM card is not upgraded, and the terminal can access to the internet through network signals provided by the first SIM card, thereby improving user experience.

It should be noted that, in a scenario where there is no RPLMN in the PLMN list of the terminal and there is an HPLMN, the first PLMN is the HPLMN. Or in the scenario that the RPLMN and the HPLMN are not present in the PLMN list of the terminal, but the OPLMN is present, the first PLMN is the HPLMN.

For an illustration of this scenario, reference may be made to the description in the above embodiments, and no further description is given here.

For example, as shown in fig. 4, the searching, by the terminal, for a frequency point corresponding to a cell covered by the first network system may include the following steps:

s1041, the terminal adds information of the first network system in the system information corresponding to the first PLMN.

The first network system is an NR system (or 5G system); or the first network system is an LTE system (or called a 4G system).

In the case that the first PLMN is an HPLMN, in combination with the table 2, the terminal may add an NR format to the RAT corresponding to the HPLMN; or the terminal may add LTE standard in RAT corresponding to HPLMN.

In the case that the first PLMN is an OPLMN, in combination with the table 2, the terminal may add an NR format to a RAT corresponding to the OPLMN; or the terminal may add the LTE standard to the RAT corresponding to the OPLMN.

For example, after adding the information of the first network system to the system information corresponding to the first PLMN, the information of PLMNs corresponding to PLMNs with different priority levels in a PLMN list maintained in the terminal may be shown in table 3.

TABLE 3 Table 3

PLMN list	MCC	MNC	RAT
				HPLMN	460	01	GSM, UMTS, LTE (or NR)
OPLMN	460	01	GSM, UMTS, LTE (or NR)

S1042, the terminal selects a first PLMN and searches the frequency point corresponding to the cell covered by the first network system.

Illustratively, in connection with table 3, after powering on, the terminal first selects the HPLMN and searches for cells under the HPLMN. As shown in table 3 above, when the terminal searches for a cell under the RPLMN, the first SIM card in the terminal supports access to multiple network systems (e.g., GSM, UMTS, LTE, NR). Then, under the HPLMN, the terminal searches the frequency point corresponding to the cell covered by the NR system, if the terminal searches the cell covered by the NR system, the terminal resides in the cell corresponding to the NR system through the first SIM card.

In the scheme, after the NR mode is added in the mode information corresponding to the HPLMN, the first SIM card in the terminal can be enabled to rapidly reside in a cell corresponding to a high mode (such as the NR mode).

Or under the scene that the HPLMN does not exist in the PLMN list maintained by the terminal, after the terminal is started, the terminal firstly selects the OPLMN and searches the cell under the OPLMN. The specific searching process may refer to the above description, and will not be described herein.

Based on the above scheme, since the terminal adds the first network system in the system information corresponding to the OPLMN, when the terminal selects the OPLMN and searches the cell under the OPLMN, the first SIM card in the terminal can also be made to quickly reside in the cell corresponding to the first network system (such as NR system).

It will be appreciated that the information of the PLMN is stored in the form of a database in a card file (also referred to as an EFS file) of the first SIM card. When the terminal is started, the terminal can read PLMN information from the card file of the first SIM card, and copy the PLMN information into a local PLMN list, namely, the PLMN list maintained by the terminal. Wherein the terminal may maintain a PLMN list in a Modem (Modem). Further, after the terminal is started, the terminal may select a PLMN with a high priority to perform cell search according to the order of the priority from high to low based on the PLMN list maintained by the terminal. After the terminal selects a proper PLMN, the terminal searches a frequency point corresponding to a cell covered by the first network system under the PLMN.

As shown in fig. 5, in S1041, the terminal adds the first network system to the system information corresponding to the first PLMN, which may be implemented as follows.

Mode one: and in the process of reading the card file of the first SIM card by the terminal, modifying the card file of the first SIM card, and adding a first network system in the system information corresponding to the first PLMN.

In an exemplary process, the terminal sets a bit field (i.e., bit field) of the first network system from "0" to "1" in the system information corresponding to the first PLMN in the process that the terminal reads the card file of the first SIM card.

For example, the terminal sets "0" to "1" in the bit fields of the NR system and the LTE system in the system information corresponding to the first PLMN.

Mode two: in the process that the terminal copies the card file of the first SIM card to the Modem, the card file of the first SIM card is modified, and a first network system is added in system information corresponding to the first PLMN.

For the implementation manner of the second embodiment, reference may be made to the foregoing manner one, which is not repeated herein.

Or the terminal can also modify the card file of the first SIM card after reading the card file of the first SIM card, and add the first network system in the system information corresponding to the first PLMN. Of course, the terminal may also modify the card file of the first SIM card at other times, which is not listed here.

The terminal executes an automatic network selection process after the terminal is started up under the condition that the information of the first network system is added to the system information corresponding to the first PLMN according to the first mode or the second mode, that is, the terminal selects a suitable PLMN according to the priority order of the PLMN list, and performs cell search under the PLMN. For specific implementation, reference may be made to the description of the above embodiments, and details are not repeated here.

Based on the scheme, the first network system is added in the system information corresponding to the first PLMN by modifying the card file of the first SIM card, so that the first SIM card can be quickly resided in a cell corresponding to a high system.

For example, as shown in fig. 6, the adding, by the terminal, information of the first network system to the system information corresponding to the first PLMN may include the following steps:

S1041a, before the terminal selects the first PLMN, the terminal reads a first card file of the first SIM card when the terminal is started, and modifies the first card file of the first SIM card in the process of reading the first card file of the first SIM card, and adds information of a first network system into system information corresponding to the first PLMN to obtain a second card file of the first SIM card.

Wherein, the system information corresponding to the first PLMN included in the first card file of the first SIM card does not have a first network system; the second card file of the first SIM card comprises the system information corresponding to the first PLMN and has a first network system.

Illustratively, the first card file of the first SIM card includes an HPLMN file and an OPLMN file. When the first PLMN is the HPLMN, the terminal adds a first network mode in mode information corresponding to the HPLMN file in the process of reading a first card file of the first SIM card. In this way, the second card file of the first SIM card obtained by the terminal includes an HPLMN file and an OPLMN file, and the system information corresponding to the HPLMN file includes the first network system.

Correspondingly, when the first PLMN is OPLMN, the terminal adds a first network format (for example, NR format) in format information corresponding to the OPLMN file in a process of reading the first card file of the first SIM card. In this way, the second card file of the first SIM card obtained by the terminal includes the HPLMN file and the OPLMN file, and the format information corresponding to the OPLMN file includes the first network format (for example, NR format).

After the terminal obtains the second card file of the first SIM card, the terminal selects the first PLMN to perform cell search, and searches a frequency point corresponding to a cell covered by the first network system may include the following steps:

And S1042a, the terminal copies the second card file of the first SIM card into the Modem.

S1042b, the terminal selects a first PLMN through the Modem, and searches a frequency point corresponding to a cell covered by a first network system.

The terminal copies the second card file of the first SIM card into a PLMN list maintained in the Modem, for example. In combination with table 3, when the first PLMN is an HPLMN, the system information corresponding to the HPLMN in the PLMN list maintained in the terminal includes a first network system (such as an NR system or an LTE system). And then, the terminal selects an HPLMN to search the cell through the Modem, and searches the frequency point corresponding to the cell covered by the first network system.

Or when the first PLMN is an OPLMN, in the PLMN list maintained in the terminal, the system information corresponding to the OPLMN includes a first network system (such as an NR system or an LTE system). And then, the terminal selects OPLMN to search the cell through the Modem, and searches the frequency point corresponding to the cell covered by the first network system.

In one example, in a process of reading a first card file of a first SIM card by a terminal, a switch control item related to modifying the card file of the first SIM card is in an enabled state, and in a case that the switch control item is in the enabled state, it indicates that the terminal can modify the first card file of the first SIM card, to obtain a second card file of the first SIM card.

The terminal may be configured to control the associated switch control item to be in the enabled state when the terminal recognizes that the terminal starts reading the first card file of the first SIM card.

The switch control item is a relevant function entry which is preconfigured in the terminal and is used for indicating the terminal to modify the first card file of the first SIM card. Illustratively, the switch control being in the enabled state can be understood as: the switch control item is in an open state.

Illustratively, the above-described associated switch control items may include: a first switch control item and a second switch control item. The first switch control item is used for indicating that the terminal can modify a first card file of the first SIM card, and a first network system is added in system information corresponding to an HPLMN file included in the first card file. The second switch control item is used for indicating that the terminal can modify the first card file of the first SIM card, and a first network system is added in the system information corresponding to the OPLMN file included in the first card file.

For example, in a scenario in which no RPLMN exists in the PLMN list of the terminal and an HPLMN exists, the terminal may control the first switch control item to be in an enabled state. In the scenario where the RPLMN and the HPLMN are not present in the PLMN list of the terminal, but the OPLMN is present, the terminal may control the second switch control item to be in an enabled state.

Or in a scenario where no RPLMN exists in the PLMN list of the terminal and an HPLMN exists, the terminal may control the second switch control item to be in an enabled state. In the scenario where the RPLMN and the HPLMN are not present in the PLMN list of the terminal, but the OPLMN is present, the terminal may control the first switch control item to be in an enabled state.

Based on the above scheme, by setting the related switch control item of the first card file for modifying the first SIM card, the related switch control item can be turned on again on the basis of meeting the above scenario, so as to execute the network selection method of the embodiment of the present application, thereby ensuring the reliability of scheme execution. Furthermore, on the basis of not satisfying the above scenario, the relevant switch control item may not be turned on to reduce power consumption.

In addition to the methods shown in fig. 4, fig. 5, and fig. 6, the embodiment of the present application further provides a network selection method, as shown in fig. 7, where, in a case where the system information corresponding to the first PLMN does not include the first network system, the cell search performed by the terminal on the first frequency point may include the following steps:

S104a, after a terminal selects a first PLMN, generating a first network searching list; the first network searching list comprises system information corresponding to the first PLMN.

For example, when performing the automatic network selection procedure, the terminal first selects a suitable PLMN (hereinafter referred to as a first PLMN) and performs a cell search under the first PLMN. The first PLMN may support a plurality of different network systems, so when the terminal performs cell search under the first PLMN, the terminal may generate a first network search list based on the system information corresponding to the first PLMN.

For example, in the case that the system information corresponding to the first PLMN does not include information of the first network system (such as LTE system or NR system), the first network search list generated by the terminal includes: GSM standard and UMTS standard.

S104b, the terminal adds the information of the first network system in the first network searching list to obtain a second network searching list.

The method includes that in the process of generating a first network searching list, a first network system (LTE system or NR system) is added to the first network searching list by the terminal, so that a second network searching list obtained by the terminal includes: GSM system, UMTS system, LTE system (or NR system).

And S104c, the terminal searches the frequency point corresponding to the cell covered by the first network system according to the second network searching list.

For example, based on the second network searching list in S104b, the terminal searches the frequency point corresponding to the cell covered by the NR system under the first PLMN. If the frequency point corresponding to the cell covered by the NR system is searched, the terminal resides in the cell corresponding to the NR system through the first SIM card. If the frequency point corresponding to the cell covered by the NR system is not searched, the terminal searches the frequency point corresponding to the cell covered by the LTE system. For such a push, reference is made to the above description, and no further description is given here.

Based on the scheme, the terminal adds the information of the first network system in the first network searching list in the process of generating the first network searching list, so that the second network searching list is obtained. And then, the terminal can search the frequency point corresponding to the cell covered by the first network system according to the second network searching list, so that the terminal can quickly reside in the cell corresponding to the first network system (namely, high system) through the first SIM card.

It should be noted that, in the embodiment of the present application, the terminal may further execute the scheme shown in fig. 7 on the basis of the scheme shown in fig. 6. That is, in the process of reading the first card file of the first SIM card, the terminal modifies the first card file of the first SIM card, adds the first network system to the system information corresponding to the first PLMN, and in the process of generating the first network searching list by the terminal, adds the first network system to the first network searching list to obtain the second network searching list, and searches the frequency point corresponding to the cell covered by the first network system based on the second network searching list.

In this way, when the terminal reads the first card file of the first SIM card, and the first network system added in the system information corresponding to the first PLMN is not effective (or fails to be added due to network reasons), the reliability of the first SIM card of the terminal in the cell corresponding to the first network system can be improved, and further the reliability of the network selection method can be improved, because the terminal also adds the first network system in the first network search list in the process of generating the first network search list.

The content described in each embodiment of the present application can be explained and explained in other embodiments of the present application, and the technical features described in each embodiment can be applied to other embodiments, and the present application is not limited to these embodiments, but can be combined with the technical features described in other embodiments to form new embodiments.

The embodiment of the application provides a terminal, which comprises a first SIM card, wherein the terminal supports access to a first network system, and an account corresponding to the first SIM card has the authority to access the first network system; the terminal may further include: a memory and one or more processors; the memory has stored therein computer program code comprising computer instructions which, when executed by the processor, cause the terminal to perform the various functions or steps described above as being performed in the terminal. The structure of the terminal may refer to the structure of the terminal 100 described below.

Fig. 8 is a schematic structural diagram of a terminal 100 according to an embodiment of the present application. Wherein, the terminal 100 may include: processor 110, external memory interface 120, internal memory 121, universal serial bus (universal serial bus, USB) interface 130, charge management module 140, power management module 141, battery 142, antenna 1, antenna 2, mobile communication module 150, wireless communication module 160, audio module 170, speaker 170A, receiver 170B, microphone 170C, headset interface 170D, sensor module 180, positioning module 181, keys 190, motor 191, indicator 192, camera 193, display 194, and subscriber identity module (subscriber identification module, SIM) card interface 195, etc.

It is to be understood that the structure illustrated in this embodiment does not constitute a specific limitation on the terminal 100. In other embodiments, terminal 100 may include more or less components than illustrated, or certain components may be combined, or certain components may be split, or different arrangements of components. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

The processor 110 may include one or more processing units, such as: processor 110 may include an application processor (application processor, AP), a Modem processor (Modem), a graphics processor (graphics processing unit, GPU), an image signal processor (IMAGE SIGNAL processor, ISP), a controller, a memory, a video codec, a digital signal processor (DIGITAL SIGNAL processor, DSP), a baseband processor, and/or a neural-network processor (neural-network processing unit, NPU), etc. Wherein the different processing units may be separate devices or may be integrated in one or more processors.

The controller may be a neural hub and command center of the terminal 100. The controller can generate operation control signals according to the instruction operation codes and the time sequence signals to finish the control of instruction fetching and instruction execution.

A memory may also be provided in the processor 110 for storing instructions and data. In some embodiments, the memory in the processor 110 is a cache memory. The memory may hold instructions or data that the processor 110 has just used or recycled. If the processor 110 needs to reuse the instruction or data, it can be called directly from the memory. Repeated accesses are avoided and the latency of the processor 110 is reduced, thereby improving the efficiency of the system.

In some embodiments, the processor 110 may include one or more interfaces. It should be understood that the interfacing relationship between the modules illustrated in the present embodiment is only illustrative, and does not limit the structure of the terminal 100. In other embodiments, the terminal 100 may also use different interfacing manners in the above embodiments, or a combination of multiple interfacing manners.

The charge management module 140 is configured to receive a charge input from a charger. The charger can be a wireless charger or a wired charger. The charging management module 140 may also supply power to the electronic device through the power management module 141 while charging the battery 142.

The power management module 141 is used for connecting the battery 142, and the charge management module 140 and the processor 110. The power management module 141 receives input from the battery 142 and/or the charge management module 140 and provides power to the processor 110, the internal memory 121, the external memory, the display 194, the camera 193, the wireless communication module 160, and the like.

The wireless communication function of the terminal 100 may be implemented by the antenna 1, the antenna 2, the mobile communication module 150, the wireless communication module 160, a modem processor, a baseband processor, and the like.

Terminal 100 implements display functions via a GPU, display 194, and application processor, etc. The GPU is a microprocessor for image processing, and is connected to the display 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or change display information.

The display screen 194 is used to display images, videos, and the like. The display 194 includes a display panel. The display panel may employ a Liquid Crystal Display (LCD), an organic light-emitting diode (OLED), an active-matrix organic LIGHT EMITTING diode (AMOLED), a flexible light-emitting diode (FLED), a Mini-LED, a Micro-OLED, a quantum dot light-emitting diode (QLED), or the like.

The terminal 100 may implement audio functions through an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, an application processor, and the like. Such as music playing, recording, etc.

The audio module 170 is used to convert digital audio information into an analog audio signal output and also to convert an analog audio input into a digital audio signal. The audio module 170 may also be used to encode and decode audio signals. The speaker 170A, also referred to as a "horn," is used to convert audio electrical signals into sound signals. A receiver 170B, also referred to as a "earpiece", is used to convert the audio electrical signal into a sound signal. Microphone 170C, also referred to as a "microphone" or "microphone", is used to convert sound signals into electrical signals. The earphone interface 170D is used to connect a wired earphone.

The external memory interface 120 may be used to connect an external memory card, such as a Micro SD card, to enable expansion of the memory capabilities of the electronic device. The external memory card communicates with the processor 110 through an external memory interface 120 to implement data storage functions. For example, audio, video, etc. files are stored in an external memory card.

The internal memory 121 may be used to store computer executable program code including instructions. The processor 110 executes various functional applications of the electronic device and data processing by executing instructions stored in the internal memory 121. For example, in an embodiment of the present application, the processor 110 may include a storage program area and a storage data area by executing instructions stored in the internal memory 121.

The storage program area may store an application program (such as a sound playing function, an image playing function, etc.) required for at least one function of the operating system, etc. The storage data area may store data created during use of the electronic device (e.g., audio data, phonebook, etc.), and so forth. In addition, the internal memory 121 may include a high-speed random access memory, and may further include a nonvolatile memory such as at least one magnetic disk storage device, a flash memory device, a universal flash memory (universal flash storage, UFS), and the like.

By way of example, the processor 110 may execute computer-executable program code comprising instructions stored in the internal memory 121. The processor 110 executes the instructions to perform various functional applications and data processing of the terminal. For example, in the embodiment of the present application, the AP in the processor 110 executes corresponding steps by executing the instructions stored in the internal memory, and sends a message to the network side through the Modem.

The keys 190 include a power-on key, a volume key, etc. The motor 191 may be used for incoming call vibration alerting as well as for touch vibration feedback. The indicator 192 may be an indicator light, may be used to indicate a state of charge, a change in charge, a message indicating a missed call, a notification, etc.

The SIM card interface 195 is used to connect a SIM card. The SIM card may be inserted into the SIM card interface 195, or removed from the SIM card interface 195 to enable contact and separation with the electronic device. The electronic device may support 1 or N SIM card interfaces, N being a positive integer greater than 1. The SIM card interface 195 may support Nano SIM cards, micro SIM cards, and the like. The same SIM card interface 195 may be used to insert multiple cards simultaneously. The types of the plurality of cards may be the same or different. The SIM card interface 195 may also be compatible with different types of SIM cards. The SIM card interface 195 may also be compatible with external memory cards. The terminal 100 interacts with the network through the SIM card to realize functions such as call and data communication. In some embodiments, the terminal 100 employs an eSIM card, i.e., an embedded SIM card. The eSIM card may be embedded in the terminal 100 and cannot be separated from the terminal 100.

As shown in fig. 8, when the terminal is powered on, a processing unit Modem included in the processor 110 may read a card file of a SIM card in the terminal, and in a process of reading the card file of the SIM card in the terminal, the Modem may modify the card file of the SIM card, and add a first network system in the system information corresponding to the first PLMN.

After the Modem reads the card file of the SIM card in the terminal, the Modem copies the card file of the SIM card to the local PLMN list of the Modem. After the terminal is started, the NAS in the terminal can initiate a PLMN selection request, select a proper PLMN from a local PLMN list, and search cells under the PLMN. If the terminal finds an available cell, the terminal performs residence and initiates network registration.

The embodiment of the application also provides a chip system which is applied to the terminal, the terminal comprises a first SIM card, the terminal supports access to a first network system, and an account corresponding to the first SIM card has the authority to access the first network system. As shown in fig. 9, the chip system 1100 includes at least one processor 1101 and at least one interface circuit 1102. The processor 1101 may be the processor 110 shown in fig. 8 in the above embodiment. The interface circuit 1102 may be, for example, an interface circuit between the processor 110 and an external memory; or as interface circuitry between the processor and the internal memory 121.

The processor 1101 and interface circuit 1102 may be interconnected by wires. For example, the interface circuit 1102 may be used to receive signals from other devices, such as the memory of the cell phone 100. For another example, the interface circuit 1102 may be used to send signals to other devices (e.g., the processor 1101). The interface circuit 1102 may, for example, read instructions stored in a memory and send the instructions to the processor 1101. The instructions, when executed by the processor 1101, may cause the terminal to perform the various steps performed by the first terminal in the embodiments described above. Of course, the system-on-chip may also include other discrete devices, which are not particularly limited in accordance with embodiments of the present application.

The embodiment of the application also provides a computer readable storage medium, which comprises computer instructions, when the computer instructions run on a terminal, the terminal is caused to execute the functions or steps executed by the terminal in the embodiment of the method.

The embodiment of the application also provides a computer program product, which when run on a computer, causes the computer to perform the functions or steps performed by the terminal in the above-mentioned method embodiment.

It will be apparent to those skilled in the art from this description that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and the parts displayed as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions for causing a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read Only Memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The network selecting method is characterized by being applied to a terminal comprising a first Subscriber Identity Module (SIM) card, wherein the terminal supports access to a first network system, and an account corresponding to the first SIM card has the authority to access the first network system; the method comprises the following steps:

In a scenario that a public land mobile network (RPLMN) registered with a Public Land Mobile Network (PLMN) is not present in a PLMN list of the terminal, but a first PLMN is present, the terminal determines that system information corresponding to the first PLMN does not have the first network system; wherein the first PLMN is a local public land mobile network HPLMN; or the first PLMN controls the public land mobile network OPLMN for an operator;

When the system information corresponding to the first PLMN does not exist in the first network system, the terminal adds the information of the first network system in the system information corresponding to the first PLMN, selects the first PLMN and searches a frequency point corresponding to a cell covered by the first network system;

When the terminal searches the cell covered by the first network system, the terminal resides in the cell corresponding to the first network system through the first SIM card.

2. The method of claim 1, wherein the step of determining the position of the substrate comprises,

In a scenario in which the RPLMN is not present in the PLMN list of the terminal and the HPLMN is present, the first PLMN is the HPLMN; or alternatively

The first PLMN is the OPLMN in a scenario where the RPLMN and the HPLMN are not present but the OPLMN is present in the PLMN list of the terminal.

3. The method according to claim 1 or 2, wherein the scenario in which the RPLMN is not present in the PLMN list of the terminal, but the first PLMN is present, comprises:

The method comprises the steps of starting up the terminal for the first time after the operating system of the terminal is automatically upgraded, starting up the terminal for the first time after the terminal leaves the factory, starting up the terminal after the terminal recovers the factory setting, or starting up the terminal after the operating system of the terminal is reinstalled.

4. The method of claim 1, wherein the terminal comprises a Modem; the terminal adds the information of the first network system to the system information corresponding to the first PLMN, and the method comprises the following steps:

The terminal reads a first card file of the first SIM card, modifies the first card file of the first SIM card, adds the information of the first network system into the system information corresponding to the first PLMN, and obtains a second card file of the first SIM card;

The terminal selects the first PLMN, searches a frequency point corresponding to a cell covered by the first network system, and includes:

the terminal copies a second card file of the first SIM card into the Modem;

And the terminal selects the first PLMN through the Modem and searches the frequency point corresponding to the cell covered by the first network system.

5. The method of claim 4, wherein said modifying the first card file of the first SIM card comprises:

and modifying the first card file of the first SIM card in the process of reading the first card file of the first SIM card by the terminal.

6. The method of claim 5, wherein modifying the first card file of the first SIM card during the process of reading the first card file of the first SIM card by the terminal comprises:

in the process that the terminal reads the first card file of the first SIM card, a switch control item related to modifying the first card file of the first SIM card is in an enabling state;

And under the condition that the switch control item is in an enabling state, the terminal modifies a first card file of the first SIM card.

7. The method according to claim 1 or 2, wherein the terminal selecting the first PLMN and searching the frequency point corresponding to the cell covered by the first network system includes:

after the terminal selects the first PLMN, a first network searching list is generated; the first network searching list comprises system information corresponding to the first PLMN;

the terminal adds the information of the first network system into the first network searching list to obtain a second network searching list;

and the terminal searches the frequency point corresponding to the cell covered by the first network system according to the second network searching list.

8. The method of any one of claims 1, 2 or 4-6,

The first network system is a 5G system; or alternatively

The first network system is a 4G system.

9. A terminal, characterized in that the terminal comprises a first subscriber identity module, SIM, card; the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority for accessing the first network system; the terminal further comprises:

A memory and one or more processors;

The memory has stored therein computer program code comprising computer instructions; the computer instructions, when executed by the processor, cause the terminal to perform the method of any of claims 1-8.

10. The chip system is characterized by being applied to a terminal, wherein the terminal comprises a first Subscriber Identity Module (SIM) card; the terminal supports access to a first network system, and an account corresponding to the first SIM card has authority for accessing the first network system; the chip system includes: at least one processor and an interface for receiving instructions and transmitting to the at least one processor; the at least one processor executing the instructions causes the terminal to perform the method of any of claims 1-8.

11. A computer readable storage medium comprising computer instructions which, when run on a terminal, cause the terminal to perform the method of any of claims 1-8.