CN113498123B

CN113498123B - Network access system, method and terminal

Info

Publication number: CN113498123B
Application number: CN202010200462.3A
Authority: CN
Inventors: 丁明; 徐自翔; 卢静静
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-03-20
Filing date: 2020-03-20
Publication date: 2023-06-02
Anticipated expiration: 2040-03-20
Also published as: CN113498123A; WO2021185100A1

Abstract

The present disclosure relates to the field of mobile communications technologies, and in particular, to a network access system, a network access method, and a terminal. The system comprises 4G access network equipment, 5G access network equipment and a terminal; wherein, the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR; when the terminal resides in a network provided by the 5G access network equipment and the terminal performs voice service, the 5G access network equipment can instruct the terminal to be connected to the 4G access network equipment through an EPS fallback program so as to enable the terminal to perform the voice service through the 4G access network equipment; when the voice service is ended and the terminal and the 4G access network equipment keep RRC connection, the terminal actively transmits a measurement report to the 4G access network equipment so as to enable the terminal to be reconnected to the 5G access network equipment. In the system, when the EPS fallback voice service is finished and the terminal is in a connection state under the 4G network, the terminal can actively send a measurement report to the network side so as to return to the 5G network as soon as possible.

Description

Network access system, method and terminal

Technical Field

The present disclosure relates to the field of mobile communications technologies, and in particular, to a network access system, a network access method, and a terminal.

Background

The voice service is required to be covered by the network, and the radio access network (radio access network, RAN) of the fifth generation ((5th generation,5G) mobile communication system, i.e. the next generation radio access network (next generation radio access network, NG RAN) is mostly in the high frequency band, the high frequency band network has a small signal coverage, which is difficult to meet the coverage requirement of the voice service.

After the voice service is finished, in order for the terminal to make full use of the more stable, higher speed, and more reliable network performance provided by the 5G network, it is necessary for the terminal to return to the 5G network as soon as possible.

Disclosure of Invention

The embodiment of the specification provides a network access system, a network access method and a terminal, which can enable the terminal to actively send a measurement report to a network side after the voice call falling back by EPS is ended, so as to trigger a network to measure and issue a measurement control message of a different system, and enable the terminal to quickly return to a 5G network.

In a first aspect, embodiments of the present disclosure provide a network access system, including a 4G access network device, a 5G access network device, and a terminal; wherein, the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR; when the terminal resides in a network provided by the 5G access network equipment and the terminal performs voice service, the 5G access network equipment can instruct the terminal to be connected to the 4G access network equipment through an EPS fallback program so as to enable the terminal to perform the voice service through the 4G access network equipment; the terminal can receive the hang-up operation initiated by the user and respond to the hang-up operation to end the voice service; or the terminal is used for receiving the hang-up indication from the 4G access network equipment and ending the voice service in response to the hang-up indication; when the terminal and the 4G access network equipment keep RRC connection, the terminal is used for actively sending a measurement report to the 4G access network equipment so as to enable the terminal to be reconnected to the 5G access network equipment.

That is, in the network access system provided in the embodiment of the present application, when a terminal accessing to a 5G network performs a voice service, the terminal may access to a 4G network through an EPS fallback procedure to perform the voice service; when the voice service is finished, if the terminal is in a connection state under the 4G network, the terminal can actively send a measurement report to the network side so as to return to the 5G network as soon as possible.

In one possible implementation, the 4G access network device is configured to send a different system measurement control message to the terminal in response to the measurement report, where the different system measurement control message is configured to trigger the terminal to measure a signal quality of a different system neighbor cell.

That is, in this implementation, the measurement report actively sent by the terminal to the network side may trigger the network side to issue a different system measurement control message, which may trigger the terminal residing in the 4G network to measure the signal quality of the 5G network, so that the 5G network may be accessed.

In one possible implementation, the method for actively sending the measurement report to the 4G access network device by the terminal includes: and when the terminal does not receive the inter-system measurement control message in a first time period, the terminal is used for actively sending a measurement report to the 4G access network equipment, and the first time period is a time period started when or after the voice service is ended.

That is, in this implementation manner, after the voice service is finished, the terminal may wait for the network side to issue the inter-system measurement control message first, and if the inter-system measurement message issued by the network side is not waited for a certain period of time, the terminal actively sends a measurement report to the network side, so as to return to the 5G network as soon as possible, and avoid collision with the inter-system measurement control message issued normally by the network side.

In one possible implementation, the method for the terminal to send the measurement report by the active 4G access network device includes: the terminal is used for determining that the terminal meets a first condition; wherein the first condition comprises at least one of:

the method comprises the steps that delay sensitive data service is not executed, voice service is not an emergency call service, the voice service is not in an emergency call callback mode, the execution duration of the voice service is smaller than a first threshold value, the moving speed of a terminal is smaller than a second threshold value during the execution of the voice service, the voice service is not in an EN-DC state, and the voice service is not in a test mode;

and the terminal is used for actively sending the measurement report to the 4G access network equipment.

That is, in this implementation, the terminal first determines whether the terminal is currently executing a specific type of service, and if the type of service is affected by the procedure of re-accessing the 5G network, the user network experience may be reduced. If the terminal does not execute the specific type of service currently, the terminal actively transmits a measurement report to a network side so as to access to the 5G network as soon as possible.

In one possible implementation manner, the terminal is further configured to actively measure the signal quality of the network provided by the 5G access network device when the inter-system measurement control message is not received; when the signal quality of the network provided by the 5G access network device is higher than the threshold, the terminal is further configured to actively disconnect the RRC connection between the terminal and the 4G access network device, and attempt to access the network provided by the 5G access network device.

That is, in this implementation, if the terminal does not receive the inter-system measurement control message, the terminal may actively measure the signal quality of the 5G network so as to quickly return to the 5G network.

In one possible implementation, the terminal is further configured to send an RRC connection reestablishment request to the 4G access network device when the terminal fails to attempt to access the network provided by the 5G access network device, so as to reestablish the RRC connection between the terminal and the 4G access network device.

That is, in this implementation, if the terminal fails to access the 5G network, the terminal may initiate reestablishment of the RRC connection with the 4G access network device, so as to access the 4G network as soon as possible when the access to the 5G network fails.

In a second aspect, embodiments of the present disclosure provide a network access method, including: the terminal is connected to 5G access network equipment, the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR; when the terminal performs voice service, the terminal is connected to the 4G access network equipment to perform voice service through the 4G access network equipment, wherein the terminal accesses the 4G access network equipment through the indication of the 5G access network equipment, and the indication is the indication of the 5G access network equipment through an EPS fallback program; the terminal receives a hang-up operation initiated by a user and responds to the hang-up operation to end the voice service; or the terminal receives a hang-up instruction from the 4G access network equipment and responds to the hang-up instruction to end the voice service; when the terminal and the 4G access network equipment keep RRC connection, the terminal actively transmits a measurement report to the 4G access network equipment so as to enable the terminal to be reconnected to the 5G access network equipment.

In one possible implementation, the method further includes: the terminal receives a different system measurement control message from the 4G access network device, wherein the different system measurement control message is a message sent by the 4G access network device in response to a measurement report; and the terminal responds to the inter-system measurement control message and measures the signal quality of the inter-system neighbor cell.

In one possible implementation, the terminal actively sending the measurement report to the 4G access network device includes: and when the terminal does not receive the inter-system measurement control message in a first time period, the terminal actively transmits the measurement report to the 4G access network equipment, wherein the first time period is a time period started when or after the voice service is ended.

In a possible implementation manner, the terminal actively sends the measurement report to the 4G access network device includes: the terminal determines that the terminal meets a first condition; wherein the first condition comprises at least one of:

And the terminal actively transmits the measurement report to the 4G access network equipment.

In a possible implementation manner, the method further includes: when the terminal does not receive the inter-system measurement control message, the terminal actively measures the signal quality of a first network provided by the 5G access network equipment; when the signal quality of the first network is higher than a first threshold, the terminal actively disconnects the RRC connection between the terminal and the 4G access network device and tries to access the first network.

In a possible implementation manner, the method further includes: and when the terminal fails to attempt to access the first network, sending an RRC connection reestablishment request to the 4G access network equipment so as to reestablish the RRC connection between the terminal and the 4G access network equipment.

It can be appreciated that the network access method provided in the second aspect is a method performed by the terminal in the network access system provided in the first aspect, and therefore, the advantages achieved by the method can be referred to as the corresponding advantages.

In a third aspect, embodiments of the present disclosure provide a terminal, including: a processor, a memory, a transceiver; the memory is used for storing computer instructions; when the terminal is running, the processor executes the computer instructions, causing the terminal to perform: the method comprises the steps that the method is connected to 5G access network equipment, the 5G access network equipment does not support VoNR, and/or 5G core network equipment corresponding to the 5G access network equipment does not support VoNR; when the terminal performs voice service, connecting to 4G access network equipment to perform voice service through the 4G access network equipment, wherein the terminal accesses to the 4G access network equipment through the indication of the 5G access network equipment, and the indication is the indication of the 5G access network equipment through an EPS fallback program; receiving a hang-up operation initiated by a user, and ending the voice service in response to the hang-up operation; or receiving a hang-up instruction from the 4G access network equipment, and ending the voice service in response to the hang-up instruction; and when the terminal and the 4G access network equipment keep RRC connection, actively sending a measurement report to the 4G access network equipment so as to enable the terminal to be reconnected to the 5G access network equipment.

In one possible implementation, the processor executes the computer instructions to cause the terminal to further perform: receiving a different system measurement control message from the 4G access network device, wherein the different system measurement control message is a message sent by the 4G access network device in response to a measurement report; and measuring the signal quality of the neighboring cell of the different system in response to the measurement control message of the different system.

In one possible implementation, the processor executes the computer instructions to cause the terminal to further perform: and when the terminal does not receive the inter-system measurement control message in a first time period, actively sending a measurement report to the 4G access network equipment, wherein the first time period is a time period started when or after the voice service is ended.

In one possible implementation, the processor executes the computer instructions to cause the terminal to further perform: determining that the terminal meets a first condition; wherein the first condition comprises at least one of:

the method comprises the steps that delay sensitive data service is not executed, voice service is not an emergency call service, the voice service is not in an emergency call callback mode, the execution duration of the voice service is smaller than a first threshold value, the moving speed of a terminal is smaller than a second threshold value during the execution of the voice service, the voice service is not in an evolution type unified land wireless access network-new air interface dual-connection EN-DC state, and the voice service is not in a test mode; and actively sending a measurement report to the 4G access network equipment.

In one possible implementation, the processor executes the computer instructions to cause the terminal to further perform: when the terminal does not receive the inter-system measurement control message, measuring the signal quality of a first network provided by the 5G access network equipment; and when the signal quality of the first network is higher than a first threshold, actively disconnecting the RRC connection of the terminal and the 4G access network equipment, and attempting to access the first network.

In one possible implementation, the processor executes the computer instructions to cause the terminal to further perform: and when the terminal fails to attempt to access the first network, sending an RRC connection reestablishment request to the 4G access network equipment so as to reestablish the RRC connection between the terminal and the 4G access network equipment.

It will be appreciated that the terminal provided in the third aspect is configured to perform the method provided in the second aspect, and therefore, the advantages achieved by the terminal may be referred to as the corresponding advantages described above.

In a fourth aspect, embodiments of the present disclosure provide a chip system, including: and a processor coupled to the interface circuit for executing instructions to cause a terminal on which the chip system is installed to perform the method provided in the second aspect.

In a fifth aspect, embodiments of the present description provide a computer storage medium comprising computer instructions which, when run on a terminal, cause the terminal to perform the method provided in the second aspect.

In a sixth aspect, embodiments of the present application provide a computer program product comprising program code for implementing the method provided in the second aspect when being executed by a processor in a terminal.

The network access system, the network access method and the network access terminal provided by the embodiment of the specification can enable the terminal accessed to the 5G network to access to the 4G network through the EPS fallback program to perform voice service when performing voice service; when the voice service is finished, if the terminal is in a connection state under the 4G network, the terminal can actively send a measurement report to the network side, so that the terminal can quickly return to the 5G network.

Drawings

FIG. 1 is a schematic diagram of a network system to which embodiments of the present application are applicable;

fig. 2 is a schematic structural diagram of a terminal according to an embodiment of the present application;

fig. 3 is a schematic block diagram of a software structure of a terminal according to an embodiment of the present application;

fig. 4 is a flowchart of a network access method provided in an embodiment of the present application;

FIG. 5 is a schematic diagram of a user interface according to an embodiment of the present application;

FIG. 6A is a schematic diagram of a user interface provided in an embodiment of the present application;

FIG. 6B is a schematic diagram of a user interface provided in an embodiment of the present application;

FIG. 6C is a schematic diagram of a user interface provided in an embodiment of the present application;

FIG. 6D is a schematic diagram of a user interface provided by an embodiment of the present application;

FIG. 6E is a schematic diagram of a user interface provided by an embodiment of the present application;

FIG. 7A is a schematic diagram of a user interface according to an embodiment of the present application;

FIG. 7B is a schematic diagram of a user interface provided in an embodiment of the present application;

FIG. 8 is a schematic diagram of a user interface provided in an embodiment of the present application;

fig. 9 is a flowchart of a terminal entering an EN-DC state according to an embodiment of the present application;

FIG. 10 is a schematic diagram of a user interface provided in an embodiment of the present application;

fig. 11 is a flowchart of a network access method provided in an embodiment of the present application;

fig. 12 is a schematic structural diagram of a terminal according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of a chip system according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be described below with reference to the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present specification.

Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the specification. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise.

Wherein, in the description of the present specification, "/" means or is meant unless otherwise indicated, 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: a exists alone, A and B exist together, and B exists alone. In addition, in the description of the embodiments of the present specification, "a plurality" means two or more than two.

In the description of this specification, the terms "first," "second," and the like 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. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

Fig. 1 shows a network system. The network system may include a terminal 100, an access network device 200, and an access network device 300. Wherein the access network device 200 and the access network device 300 may belong to different mobile communication systems, respectively. Illustratively, the access network apparatus 200 may be an evolved base station (evolutional node B, eNB) in a fourth generation (4th generation,4G) mobile communication system, and the access network apparatus 200 may be a next generation base station (next generation node B, gNB) in a fifth generation or new air interface (NR) mobile communication system.

The access network device 200 may be an access network device under stand-alone networking (SA). The access network device 200 may provide wireless network coverage 210 and the access network device 300 may provide wireless network coverage 310. It will be appreciated that when the access network device 300 is an access network device of a 5G mobile communication system and the access network device 200 is an access network device of a 4G mobile communication system, the range of the wireless network coverage 310 is smaller than the range of the wireless network coverage 210 and is within the wireless network coverage 210, since the spectrum of the 5G mobile communication system is generally higher than that of the 4G mobile communication system.

The terminal 100 may support various mobile communication systems, for example, a 4G mobile communication system and a 5G mobile communication system. The terminals 100 may be distributed in the network system shown in fig. 1, and may be stationary or mobile. In some embodiments of the present application, the terminal 100 may be a mobile device, a mobile station, a mobile unit, a wireless unit, a remote unit, a user agent, a mobile client, or the like. More specifically, the terminal 100 may be a portable electronic device such as a mobile phone, a tablet computer, a digital camera, a personal digital assistant (personal digitalassistant, PDA), a wearable device, a laptop computer (laptop), or the like. Exemplary embodiments of portable electronic devices include, but are not limited to, piggy-back

Or other operating system. The portable electronic device described above may also be other portable electronic devices, such as a laptop computer (laptop) or the like having a touch-sensitive surface, e.g. a touch panel. It should also be appreciated that in other embodiments of the present application, the terminal 100 may not be a portable electronic device, but rather a desktop computer having a touch-sensitive surface (e.g., a touch panel). The type of the electronic device is not particularly limited in the embodiments of the present application.

Fig. 2 shows a schematic structural diagram of the terminal 100.

The terminal 100 may include a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (universal serial bus, USB) interface 130, a charge 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, an earphone interface 170D, a sensor module 180, keys 190, a motor 191, an indicator 192, a camera 193, a display 194, and a subscriber identity module (subscriber identification module, SIM) card interface 195, etc. The sensor module 180 may include a pressure sensor 180A, a gyro sensor 180B, an air pressure sensor 180C, a magnetic sensor 180D, an acceleration sensor 180E, a distance sensor 180F, a proximity sensor 180G, a fingerprint sensor 180H, a temperature sensor 180J, a touch sensor 180K, an ambient light sensor 180L, a bone conduction sensor 180M, and the like.

It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on the terminal 100. In other embodiments of the present application, 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: the processor 110 may include an application processor (application processor, AP), a modem processor, a graphics processor (graphics processing unit, GPU), an image signal processor (image signal processor, ISP), a controller, 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 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.

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.

The antennas 1 and 2 are used for transmitting and receiving electromagnetic wave signals. Each antenna in terminal 100 may be configured to cover a single or multiple communication bands. Different antennas may also be multiplexed to improve the utilization of the antennas. For example: the antenna 1 may be multiplexed into a diversity antenna of a wireless local area network. In other embodiments, the antenna may be used in conjunction with a tuning switch.

The mobile communication module 150 may provide a solution including 2G/3G/4G/5G wireless communication applied to the terminal 100. The mobile communication module 150 may include at least one filter, switch, power amplifier, low noise amplifier (low noise amplifier, LNA), etc. The mobile communication module 150 may receive electromagnetic waves from the antenna 1, perform processes such as filtering, amplifying, and the like on the received electromagnetic waves, and transmit the processed electromagnetic waves to the modem processor for demodulation. The mobile communication module 150 can amplify the signal modulated by the modem processor, and convert the signal into electromagnetic waves through the antenna 1 to radiate. In some embodiments, at least some of the functional modules of the mobile communication module 150 may be disposed in the processor 110. In some embodiments, at least some of the functional modules of the mobile communication module 150 may be provided in the same device as at least some of the modules of the processor 110.

The modem processor may include a modulator and a demodulator. The modulator is used for modulating the low-frequency baseband signal to be transmitted into a medium-high frequency signal. The demodulator is used for demodulating the received electromagnetic wave signal into a low-frequency baseband signal. The demodulator then transmits the demodulated low frequency baseband signal to the baseband processor for processing. The low frequency baseband signal is processed by the baseband processor and then transferred to the application processor. The application processor outputs sound signals through an audio device (not limited to the speaker 170A, the receiver 170B, etc.), or displays images or video through the display screen 194. In some embodiments, the modem processor may be a stand-alone device. In other embodiments, the modem processor may be provided in the same device as the mobile communication module 150 or other functional module, independent of the processor 110.

The wireless communication module 160 may provide solutions for wireless communication including wireless local area network (wireless local area networks, WLAN) (e.g., wireless fidelity (wireless fidelity, wi-Fi) network), bluetooth (BT), global navigation satellite system (global navigation satellite system, GNSS), frequency modulation (frequency modulation, FM), near field wireless communication technology (near field communication, NFC), infrared technology (IR), etc., applied on the terminal 100. The wireless communication module 160 may be one or more devices that integrate at least one communication processing module. The wireless communication module 160 receives electromagnetic waves via the antenna 2, modulates the electromagnetic wave signals, filters the electromagnetic wave signals, and transmits the processed signals to the processor 110. The wireless communication module 160 may also receive a signal to be transmitted from the processor 110, frequency modulate it, amplify it, and convert it to electromagnetic waves for radiation via the antenna 2.

In some embodiments, antenna 1 and mobile communication module 150 of terminal 100 are coupled, and antenna 2 and wireless communication module 160 are coupled, such that terminal 100 may communicate with a network and other devices via wireless communication techniques. The wireless communication techniques may include the Global System for Mobile communications (global system for mobile communications, GSM), general packet radio service (general packet radio service, GPRS), code division multiple access (code division multiple access, CDMA), wideband code division multiple access (wideband code division multiple access, WCDMA), time division code division multiple access (time-division code division multiple access, TD-SCDMA), long term evolution (long term evolution, LTE), fifth generation, new radio, NR), BT, GNSS, WLAN, NFC, FM, and/or IR techniques, among others. The GNSS may include a global satellite positioning system (global positioning system, GPS), a global navigation satellite system (global navigation satellite system, GLONASS), a beidou satellite navigation system (beidou navigation satellite system, BDS), a quasi zenith satellite system (quasi-zenith satellite system, QZSS) and/or a satellite based augmentation system (satellite based augmentation systems, SBAS).

The software system of the terminal 100 may employ a layered architecture, an event driven architecture, a micro-core architecture, a micro-service architecture, or a cloud architecture. In the embodiment of the invention, taking an Android system with a layered architecture as an example, a software structure of the terminal 100 is illustrated.

Fig. 3 shows a block diagram of a software architecture of the terminal 100.

The layered architecture divides the software into several layers, each with distinct roles and branches. The layers communicate with each other through a software interface. In some embodiments, it will

The system is divided into four layers, namely an application program layer, an application program framework layer, an Zhuoyun row (Android run time), a system runtime layer and a kernel layer from top to bottom.

The application layer may include a series of application packages. As shown in fig. 3, the application package may include applications such as telephone, game, map, instant messaging, camera, etc.

The application framework layer provides an application programming interface (application programming interface, API) and programming framework for application programs of the application layer. The application framework layer may include some predefined functions.

As shown in FIG. 3, the application framework layers may include, in particular, a content provider (content providers), a view system (view system), and a manager (manager), wherein the manager includes an activity manager (activity manager), a location manager (location manager), a package manager (package manager), a notification manager (notification manager), a resource manager (resource manager), a telephone manager (telephony manager), a window manager (window manager), and the like.

The content provider is used to store and retrieve data and make such data accessible to applications. The data may include video, images, audio, calls made and received, browsing history and bookmarks, phonebooks, etc.

The Activity manager is used for managing the life cycle of the application program, activity stack management and the like.

The location manager is used for geographic location and status function services.

The package manager is used for providing and managing the installed application information.

The telephony manager is used to provide the communication functions of the terminal 100. Such as the management of call status (including on, hung-up, etc.).

The system runtime layer includes An Zhuoyun row libraries and native C/C++ libraries. An Zhuoyun the runtime library is responsible for scheduling and management of the android system, which includes the android running environment and the core library.

The native C/c++ library may include a plurality of functional modules. For example: browser engines (Webkit), multimedia framework standards (e.g., openMAX AL), libc libraries, multimedia frameworks (media frameworks), three-dimensional graphics processing libraries (e.g., openGL ES), and the like.

The kernel layer is a layer between hardware and software. The kernel layer may include a modem (modem) driver, an audio driver, a display driver, a bluetooth driver, a camera driver, a sensor driver, a Wi-Fi driver, a GPS driver, a key map driver, and the like.

The workflow of the terminal 100 software and hardware is illustrated below in connection with a user making a call.

When touch sensor 180K receives a touch operation, a corresponding hardware interrupt is issued to the kernel layer. The kernel layer processes the touch operation into the original input event (including information such as touch coordinates, time stamp of touch operation, etc.). The original input event is stored at the kernel layer. The application framework layer acquires an original input event from the kernel layer, and identifies a control corresponding to the input event. The touch operation is a touch click operation, the control corresponding to the click operation is a control corresponding to a dialing icon, the call application calls an interface of an application framework layer, and functions such as dialing a phone, calling and the like are realized through a modem.

Next, referring to fig. 1 and fig. 4, taking the access network device 200 as an access network device of the 4G mobile communication system, the access network device 300 as an access network device of the 5G mobile communication system, and the terminal 100 as an example to support at least the 4G mobile communication system and the 5G mobile communication system, the solution provided in the embodiments of the present application will be described. For convenience of description, the access network device of the 4G mobile communication system may be referred to as a 4G access network device or a 4G base station, and the access network device of the 5G mobile communication system may be referred to as a 5G access network device or a 5G base station.

Referring to fig. 1 and 4, when the terminal 100 is located in the range of the wireless network coverage 310, the terminal 100 may access a wireless access network (i.e., a 5G wireless access network) provided by the access network device 300 through a random access procedure. Specifically, the terminal 100 may transmit a random access preamble (random access preamble, RAP), i.e., message1, to the access network device 300; the access network device 300 may feed back a random access response (random access response, RAR), i.e. Message2, to the terminal 100; the terminal 100 may transmit a contention resolution request, i.e., message3; the access network device 300 may send a contention resolution result, i.e., message4, to the terminal 100; when the terminal receives Message4, the terminal 100 resides in the radio access network provided by the access network device 300, i.e. the terminal 100 successfully accesses the 5G radio access network.

Referring to fig. 5, when the terminal 100 successfully accesses the 5G radio access network, the radio network icon in the status bar of the terminal 100 may be a 5G network icon 501.

In the case where the terminal 100 resides in the 5G radio access network, when the terminal 100 has voice service, the voice service may be performed through the EPS fallback to the 4G network and through the 4G network.

In some embodiments, as shown in fig. 6A and 6B, in a case where the terminal 100 resides in the 5G radio access network, the terminal 100 may initiate a voice call, i.e., conduct a calling voice service, in response to an operation of making a call by the user. The voice service may particularly refer to a voice service of an IP multimedia subsystem (IP multiple subsystem, IMS), i.e. an IMS voice service. Since the 5G network of most operators may not support voice service in the early or even middle of deployment of the 5G mobile communication system, it is more preferable to provide voice service to users using EPS fallback. Thus, referring to fig. 6C, during dialing of a voice call, the terminal 100 may access from the 5G radio access network by redirection or handover into the radio access network provided by the access network device 200 (i.e. the 4G radio access network), i.e. the radio network icon in the status bar of the terminal 100 may become the 4G network icon 502. Specifically, when the terminal accessed to the 5G wireless access network has calling voice service, the terminal sends an invite signaling to the 5G core network through the 5G access network so as to trigger the session establishment process of the IMS domain and the 5G system. The 5G core network may determine whether it supports new air interface voice bearers (voice over new radio, voNR) and whether the 5G access network supports VoNR. If both the 5G core network and the 5G access network support VoNR, the 5G core network may instruct the 5G access network device to establish a voice-specific bearer. If the 5G core network does not support VoNR (e.g., the 5G core network is not configured with VoNR related software or hardware) and/or the 5G access network does not support VoNR (e.g., the 5G access network is not configured with VoNR related software or hardware), the 5G core network may instruct the 5G access network to perform EPS fallback. . And the 5G access network equipment judges whether EPS fallback is triggered or not and requests a measurement report to the terminal according to the capability of the terminal, whether an N26 interface exists between the 5G core network and the 4G core network or not and other information. And if the decision is made to trigger the EPS fallback, the 5G access network equipment instructs the terminal to access the 4G wireless access network through redirection or switching. When the terminal resides in the 4G wireless access network, the 4G core network establishes a special bearing for the voice service so as to realize voice service through the 4G network. Wherein the radio network icon in the status bar of the terminal 100 may become the 4G network icon 502 when the terminal 100 resides to the 4G radio access network.

Referring to fig. 6D and 6E, the wireless network icon in the status bar of the terminal 100 is the 5G network icon 502 during the counter-ringing period and during the call period. In other words, during the counter-ringing as well as during the call, the terminal 100 resides in the 4G radio access network.

In some embodiments, in case the terminal 100 resides in a 5G radio access network, the terminal 100 may act as a called terminal for a voice service, which may be an IMS voice service. Referring to fig. 7A, when the terminal 100 starts ringing, the wireless network icon in the status bar of the terminal 100 may change from the 5G network icon 501 to the 4G network icon 502. Specifically, when the terminal 100 has a called voice service, the terminal 100 sends an invite signaling to the 5G core network through the 5G access network to trigger a session establishment procedure of the IMS domain and the 5G system. The 5G core network may determine whether it supports VoNR and whether the 5G access network supports VoNR. If both the 5G core network and the 5G access network support VoNR, the 5G core network may instruct the 5G access network device to establish a voice-specific bearer. If the 5G core network does not support VoNR and/or the 5G access network does not support VoNR, the 5G core network may instruct the 5G access network to perform EPS fallback. And the 5G access network equipment judges whether EPS fallback is triggered or not and requests a measurement report to the terminal according to the capability of the terminal, whether an N26 interface exists between the 5G core network and the 4G core network or not and other information. And if the decision is made to trigger the EPS fallback, the 5G access network equipment instructs the terminal to access the 4G wireless access network through redirection or switching. When the terminal resides in the 4G wireless access network, the 4G core network establishes a special bearing for the voice service so as to realize voice service through the 4G network. Wherein the radio network icon in the status bar of the terminal 100 may become the 4G network icon 502 when the terminal 100 resides to the 4G radio access network.

Referring to fig. 7B, during a voice service call in which the terminal 100 is a called terminal, the wireless network icon in the status bar of the terminal 100 is a 4G network icon 502.

Referring to fig. 8, when the above-mentioned voice service of the terminal 100 being the calling terminal or the called terminal ends, i.e., the voice service of the EPS fallback ends, the terminal 100 still resides in the 4G radio access network. In order to take advantage of the more stable, higher speed, more reliable network performance provided by the 5G radio access network, it is necessary for the terminal 100 to return from the 4G radio access network to the 5G radio access network. Returning from the 4G network to the 5G network may have the following solution.

a1, in the case that the terminal is in the 4G radio access network and is in a connected state (connected), the network side issues a measurement control message of an event B1 (event B1) to the terminal. The terminal may respond to the measurement control message of the event B1, and report the signal energy of the neighboring cell of the different system to the network side when the measurement result indicates that the signal energy of the neighboring cell of the different system is higher than the measurement threshold (inter RAT neighbour becomes better than threshold). The network side can trigger the terminal to return to the 5G wireless access network through redirection according to the signal energy of the different system neighbor cells reported by the terminal.

a2, under the condition that the terminal is in the 4G wireless access network and is in a connected state (connected), the network side transmits a measurement control message of the event B1 to the terminal. The terminal can respond to the measurement control message of the event B1, and report the signal energy of the neighboring cell of the different system to the network side when the measurement result shows that the signal energy of the neighboring cell of the different system is higher than the measurement threshold. The network side can trigger the terminal to switch from the 4G wireless access network to the 5G wireless access network according to the signal energy of the different system neighbor cells reported by the terminal.

a3, under the condition that the terminal is in the 4G wireless access network and is in an idle state (idle), the network side transmits different system reselection configuration to the terminal, the terminal is triggered to execute a different system reselection process, and then the terminal returns to the 5G wireless access network through reselection.

a4, under the condition that the terminal is in the 4G wireless access network and is in an idle state (idle), the network side transmits a wireless resource control (radio resource control, RRC) release (release) to the terminal. The terminal returns to the 5G radio access network by means of autonomous fast return (fast return).

a5, in the case that the terminal is in the 4G wireless access network and is in an idle state (idle), the terminal searches for a 5G cell in the case of camping on a cell of long term evolution (long term evolution, LTE). When a 5G cell is searched, the terminal may return to the 5G radio access network.

From the above description, it can be seen that, in the case where the terminal resides in the 4G radio access network and is in a connected state (connected), the terminal needs to wait for the measurement control message of the event B1 issued by the network side, and then perform measurement of the inter-system neighbor cell, etc., so as to return to the 5G network. However, in practical application, especially in the immature stage of deployment of the 5G mobile communication system, the network side may not issue the measurement control message of the event B1 for a long time after the end of the voice call dropped by the EPS. For example, the measurement control message of the event B1 needs to be triggered by a high-rate service, and if the terminal does not have the high-rate service in a long time after the end of the voice call dropped by the EPS, the network side does not issue the measurement control message of the event B1. For another example, the network side does not open the function of issuing the measurement control message of the event B1, and therefore, the network side does not issue the measurement control message of the event B1. In addition, since the terminal is in a connected state, the terminal cannot return to the 5G network through the schemes a3, a4, a 5.

The embodiment of the present application provides a network access method, which may actively send a measurement report E1 to an access network device 200 when or after an EPS fallback voice service of the terminal 100 ends and the terminal 100 is in a connection state of a 4G network, so as to induce the access network device 200 to send different system measurement control information to the terminal 100, so as to trigger the terminal 100 to return to a flow of a 5G access network, thereby realizing that the EPS fallback voice service returns to the 5G network quickly after the end, and improving network experience of a user. In the embodiment of the present application, the measurement report E1 actively sent by the terminal 100 refers to a false measurement report for inducing the network side to issue a measurement control message of a different system, which is a false measurement report actively sent by the terminal 100 to the network side without according to an actual measurement result or without a measurement result.

Next, with continued reference to fig. 4, in different embodiments, an example description will be given of a network access method provided in an embodiment of the present application.

The terminal 100 may perform step 401 to determine that the voice service is ended and is in a connection state under the 4G network.

The terminal 100 may determine that the voice service of the EPS fallback ends. For example, the terminal 100 may determine that VoLTE ends in response to a hang-up operation by a user or a hang-up instruction issued by the access network device 200, and determine that VoLTE is a voice service performed through EPS fallback. In one example, the terminal 100 may record that the terminal 100 has fallen back from the 5G network to the 4G network while performing the voice service, so that it may be determined that the voice service is a voice service performed through EPS fallback. In one example, when VoLTE ends and is a voice service through EPS fallback, the terminal 100 may modify the value of "volte_ END, callStartInNrFlag" to "true". Therefore, when the terminal 100 detects volte_ END, callStartInNrFlag =true, it can be determined that the voice service of the EPS fallback ends. The hang-up indication is an indication issued by the access network device 200 to the terminal 100 when the voice service is hung up by the peer device. The opposite terminal device is the other terminal of the terminal 100 performing the voice service. In one example, the hang up indication may be BYE signaling.

For convenience of description, the voice service where EPS falls back may be referred to as a voice service V1.

When the voice service V1 ends, the terminal 100 may determine whether it is in the RRC connected state, i.e., whether an RRC link exists between it and the network side (e.g., the access network device 200).

In one illustrative example, the terminal 100 may determine whether it is in an RRC connected state in the following manner.

As described above, when EPS fallback is performed, the terminal 100 accesses the 4G radio access network by redirection or handover. Illustratively, the terminal 100 may re-directionally or switchably access the 4G radio access network by establishing an RRC link with the access network device 200 through a random access procedure. The random access procedure of the 4G network is similar to that of the 5G network, and thus, the random access procedure of the 4G network may refer to the description of the random access procedure of the 5G network above, and will not be repeated here.

After establishing the RRC link between the terminal 100 and the access network device 200, if the terminal 100 receives an RRC connection release (RRC connection release) message from the access network device 200, the RRC link is released and the terminal 100 enters an RRC idle state. If the terminal 100 does not receive the RRC connection release message from the access network device 200, the RRC link between the terminal 100 and the access network device 200 continues to be maintained, and the terminal 100 continues to be in the RRC connected state. In general, the access network device 200 may issue an RRC connection release message to the terminal 100 when there is no traffic data transmission between the terminal 100 and the access network device 200.

Therefore, the terminal 100 can determine whether it receives the RRC connection release message at the end and after the voice service V1. If the RRC connection release message is not received, it may be determined that the terminal 100 is in the RRC connected state.

In this way, the terminal 100 can determine that the voice service V1 ends, and the terminal 100 is in a connected state under the 4G network.

With continued reference to fig. 4, in the case where the voice service V1 ends and the terminal 100 is in a connection state under the 4G network, in order to trigger the network side (e.g. the access network device 200) to issue a heterogeneous system measurement control message to the terminal 100, the terminal 100 may execute step 405 to actively send a measurement report E1 to the access network device 200.

In some embodiments, the measurement report E1 may be a message for supposing that the signal quality of the serving cell of the terminal 100 is lower than the measurement threshold, so as to trigger the network side to issue a different system measurement control message to the terminal 100. The serving cell of the terminal 100 refers to a cell in which the terminal 100 currently resides.

In some embodiments, the signal quality of a cell may be characterized by the reference signal received power (reference signal receiving power, RSRP) of the cell. In this embodiment, the signal quality may also be referred to as signal energy.

In some embodiments, the signal quality of a cell may be characterized by the reference signal received quality (reference signal received quality, RSRQ) of the cell.

In some embodiments, the signal quality of a cell may be determined by the signal-to-interference-plus-noise ratio (signal to interference plus noise ratio, SINR) of the cell.

In some embodiments, the signal quality of a cell may be indicated by the received signal strength of the cell (received signal strength indication, RSSI).

In some embodiments, the signal quality of a cell may be characterized by a combination of two or more of the RSRP, RSRQ, SINR, RSSI terms of the cell.

The measurement report E1 may be, for example, in particular a pseudo measurement report or a pseudo measurement report corresponding to the event A2 (event A2).

According to the related protocol of the third generation partnership project (3rd generation partnership project,3GPP), the event A2 refers to that when the signal quality of the serving cell of the terminal is lower than a threshold value (serving becomes worse than threshold), the terminal reports a measurement report to the network side, where the measurement report is used to inform the network side that the signal quality of the serving cell thereof is lower than the threshold value, so that the network side issues a different system measurement control message to the terminal. The threshold value may be specified with reference to the 3GPP protocol and will not be described in detail herein. For convenience of description, a measurement report for informing the network side that the signal quality of its serving cell is below a threshold value, which is specified in the 3GPP existing protocol, may be referred to as a measurement report of event A2. Specifically, when the terminal is in a connection state, the network side may send a measurement control message of the A2 event to the terminal, and the terminal may measure the signal quality of the serving cell in response to the measurement control message of the A2 event. The signal quality may be RSRP, RSRQ, SINR, or RSSI. And when the signal quality of the serving cell is lower than the threshold value, the terminal reports the measurement report of the A2 event to the network side. The network side can respond to the measurement report and send out a measurement control message of the different systems to the terminal.

In the embodiment of the present application, the measurement report E1 may refer to a report directly generated by the terminal 100 without measuring the serving cell. The measurement report E1 may be a report generated when the terminal 100 measures a serving cell, but the signal quality of the serving cell is not lower than a threshold value. The measurement report E1 includes information for supposing that the signal quality of the serving cell of the terminal 100 is lower than the threshold value and/or a preset signal quality of the serving cell of the terminal 100. The preset signal quality herein refers to a signal quality set in advance, not by actual measurement.

In one illustrative example, measurement report E1 may include a measurement identification (measurement identity) of event A2. The measurement identity may also be referred to as a measurement ID. The measurement identifier of the event A2 may be used by the network side to identify the measurement report E1 as the measurement report of the event A2, so that the network side may determine or consider that the signal quality of the serving cell of the terminal 100 is lower than the threshold value, and issue the heterogeneous system measurement control information. In one example, the terminal 100 may extract the measurement identity of the event A2 from the measurement control information of the event A2, so that the measurement identity of the event A2 may be carried in the measurement report E1 when the measurement report E1 is generated. As described above, according to the existing 3GPP protocol, when the terminal 100 is in the connected state, the network side may issue the measurement control message of the event A2, where the measurement control message of the event A2 carries the measurement identifier of the event A2, so that the terminal 100 may acquire the measurement control message of the event A2 and extract the measurement identifier of the event A2.

In one illustrative example, the terminal 100 may generate the measurement report E1 with reference to the format and manner of generation of the measurement report of event A2 specified by the 3GPP existing protocol. Unlike the provision of the 3GPP existing protocol, the measurement report E1 is generated in the case where the terminal 100 does not measure the serving cell, or in the case where the serving cell is measured but the signal quality of the serving cell is not lower than the threshold value. The information in the measurement report E1, which is used to indicate that the serving cell is lower than the threshold value, is false information, and/or the signal quality of the serving cell carried by the measurement report E1 is preset signal quality. The preset signal quality herein refers to a signal quality set in advance, not by actual measurement.

In some embodiments, the measurement report E1 may be a message for assuming that the signal quality of the system neighbor of the serving cell of the terminal 100 is higher than the signal quality of the serving cell, so that the network side terminal 100 may be triggered to issue a different system measurement control message. The serving cell of the terminal 100 refers to a cell in which the terminal 100 currently resides. For convenience of description, the system neighbor cell of the serving cell may be simply referred to as the same-system neighbor cell.

The measurement report E1 may be, for example, in particular a pseudo measurement report or a pseudo measurement report corresponding to the event A3 (event A3).

According to the related protocol of the third generation partnership project, the event A3 refers to that when the signal quality of the system neighbor cell of the terminal is higher than the signal quality (neighbour becomes offset better than serving) of the serving cell, the terminal reports a measurement report to the network side, where the measurement report is used to inform the network side that the signal quality of the system neighbor cell is higher than the signal quality of the serving cell, so that the network side issues a different system measurement control message to the terminal. The threshold value may be specified with reference to the 3GPP protocol and will not be described in detail herein. For convenience of description, a measurement report for informing a network side that a signal quality of a system neighbor cell is higher than a signal quality of a serving cell, which is specified in the 3GPP existing protocol, may be referred to as a measurement report of event A3. Specifically, when the terminal is in a connection state, the network side may send a measurement control message of an A3 event to the terminal, and the terminal responds to the measurement control message of the A3 event to measure signal quality of the serving cell and the neighboring cells of the same system. The signal quality may be RSRP, RSRQ, SINR, or RSSI. When the signal quality of the system neighbor cell is higher than that of the service cell, the terminal reports the measurement report of the A3 event to the network side. The network side can respond to the measurement report and send out a measurement control message of the different systems to the terminal.

In the embodiment of the present application, the measurement report E1 may refer to a false report that the terminal 100 directly generates without measuring the serving cell and/or the system neighbor cell. The measurement report E1 may also be a false report generated when the terminal 100 measures the serving cell and the system neighbor cell, but the signal quality of the system neighbor cell is not higher than that of the serving cell. The measurement report E1 includes information for supposing that the signal quality of the system neighbor cell is higher than the signal quality of the serving cell, and/or the preset signal quality of the serving cell and the preset signal quality of the system neighbor cell. The preset signal quality herein refers to a signal quality set in advance, not by actual measurement.

In one illustrative example, measurement report E1 may include a measurement identification of event A3. The measurement identity of the event A3 may be used by the network side to identify the measurement report E1 as the measurement report of the event A3, so that the network side determines or considers that the signal quality of the system neighbor cell of the terminal 100 is higher than the signal quality of the serving cell, and issues the inter-system measurement control information. In one example, the terminal 100 may extract the measurement identity of the event A3 from the measurement control information of the event A3, so that the measurement identity of the event A3 may be carried in the measurement report E1 when the measurement report E1 is generated. As described above, according to the existing 3GPP protocol, when the terminal 100 is in the connected state, the network side may issue the measurement control message of the event A3, where the measurement control message of the event A3 carries the measurement identifier of the event A3, so that the terminal 100 may acquire the measurement control message of the event A3 and extract the measurement identifier of the event A3.

In one illustrative example, the terminal 100 may generate the measurement report E1 with reference to the format and manner of generation of the measurement report for event A3 specified by the 3GPP existing protocol. Unlike the provision of the 3GPP existing protocol, the measurement report E1 is generated by the terminal 100 without measuring the serving cell and/or without measuring the co-system neighbor cell; or the measurement report E1 is generated when the terminal 100 measures the serving cell and the system neighbor cell, but the signal quality of the system neighbor cell is not higher than that of the serving cell. The information in the measurement report E1, which is used to indicate that the signal quality of the neighboring cell with the system is higher than that of the serving cell, is false information, and/or the signal quality of the serving cell carried by the measurement report E1 and the signal quality of the neighboring cell with the system are preset signal qualities. The preset signal quality herein refers to a signal quality set in advance, not by actual measurement.

In the above manner, the terminal 100 may send the measurement report E1 to the network side (e.g., the access network device 200) to trigger the network side to send the inter-system measurement control message to the terminal 100, so as to trigger the terminal 100 to return to the procedure of the 5G radio access network.

With continued reference to fig. 4, in some embodiments, step 403 may also be performed before the terminal performs step 405, determining that the terminal 100 satisfies the condition C1, and/or starting the timer D1.

It will be appreciated that the access of a terminal from one mobile communication system to another will have an impact on the services that the terminal is currently engaged in.

In some embodiments, in order to reduce the impact of the terminal 100 accessing from one mobile communication system to another mobile communication system on the current ongoing service of the terminal 100 or to reduce the impact on important services, the terminal 100 may further determine whether the terminal 100 satisfies a certain condition C1 before sending the measurement report E1 to the network side. When the terminal 100 satisfies the condition C1, the terminal 100 transmits a measurement report E1 to the network side.

In one illustrative example, condition C1 may include condition C11, condition C11 being that the terminal is not performing delay sensitive data traffic. For example, an application blacklist may be preset, where the application blacklist includes application identifiers of a plurality of applications. The application identification may be a package name (package name) of the application. And attributing the service corresponding to the application in the application blacklist to the time delay sensitive data service. For example, the application blacklist may include gaming applications, online video playback applications, and the like. The terminal 100 may determine whether the application running in the foreground is an application in the application blacklist, for example, may acquire a package name of the application running in the foreground, and match or search the package name in the application blacklist, and if the package name matching with the package name is matched or searched, determine that the application running in the foreground is an application in the application blacklist. When the foreground running application is an application in the application blacklist, it is determined that the terminal 100 is executing the delay sensitive data service, and the terminal 100 does not satisfy the condition C11. When the foreground running application is not an application in the application blacklist, it is determined that the terminal 100 does not execute the delay sensitive data service or is not in the delay sensitive data service, and the terminal 100 satisfies the condition C11.

In one illustrative example, condition C1 may include condition C12, condition C12 being that voice service V1 is not an emergency call. For example, a telephone number blacklist may be preset. The blacklist of telephone numbers may include a plurality of emergency call numbers, such as 110, 911, 120, 112, etc. The terminal 100 may acquire a phone number corresponding to the voice service V1 when the voice service V1 is performed, for example, when a call is initiated, or during a voice call. The terminal 100 may match or search in the phone number blacklist according to the phone number corresponding to the voice service V1, and if the phone number consistent with the phone number corresponding to the voice service V1 is matched or searched, determine that the voice service V1 is an emergency call, and the terminal 100 does not satisfy the condition C12. If the telephone number corresponding to the voice service V1 is not matched or not searched, it is determined that the voice service V1 is not an emergency call, and the terminal 100 satisfies the condition C12.

In one illustrative example, condition C1 may include condition C13, condition C13 being that terminal 100 is not in emergency call callback mode. By way of example, it will be appreciated that during a period of time (5 minutes) after the voice service of the emergency call has ended, the terminal that originated the voice call is in emergency callback mode so that the emergency call center can make callback. This period of time may be referred to as the callback time of the emergency call. The callback time list may be preset, where the callback time list includes an emergency call number and callback time corresponding to the emergency call number. When the voice service V1 is an emergency call, the callback time corresponding to the emergency call number of the emergency call can be obtained through the callback time list. The terminal 100 may determine whether the time difference between the current time and the end time of the emergency call is less than the callback time. If the time difference between the current time and the ending time of the emergency call is less than the callback time, it may be determined that the terminal 100 is in the emergency callback mode, and the condition C13 is not satisfied. If the time difference between the current time and the end time of the emergency call is not less than the callback time, it may be determined that the terminal 100 is not in the emergency callback mode, and the condition C13 is satisfied.

In one illustrative example, the condition C1 may include a condition C14, the condition C14 being that the moving speed of the terminal 100 is less than the speed threshold during the execution of the voice service V1. The speed threshold may be preset empirically or experimentally, and may be, for example, 30km/h. Referring to fig. 1, before the terminal 100 performs the voice service V1, the terminal 100 is within the radio coverage provided by the 5G access network device, i.e., within the radio coverage 310. Since the spectrum of the 5G radio access network is mostly in the high frequency band. The coverage area of the high-frequency network signal is smaller, and particularly, the coverage area of the 5G wireless access network is not comprehensive in the early or middle stage of deployment of the 5G mobile communication system. If the moving speed of the terminal 100 is relatively high during the execution of the voice service V1, the terminal 100 may leave the coverage of the 5G radio access network at the end of the voice service V1, so that the attempt to access the 5G radio access network fails. If the movement speed of the terminal 100 is relatively slow, the terminal 100 is in the coverage of the 5G radio access network with a high probability when the voice service V1 ends, and therefore, it is necessary to induce the network side to issue a different system measurement control message.

In one example, the terminal 100 may measure the moving speed of the terminal 100 through the acceleration sensor 180E.

In one example, the terminal 100 measures a displacement of the terminal during the execution of the voice service V1 through a global navigation satellite system (global navigation satellite system, GNSS), and then divides the displacement by the execution duration of the voice service V1 to obtain a moving speed of the terminal 100.

The execution duration of the voice service V1 may refer to a call duration, specifically, a time difference between a time when the called party makes a call and a time when the call is hung up (a voice service end time), for example. The terminal 100 may record a time stamp of a time when the phone is connected and a time stamp of a time when the phone is hung up, and obtain a call duration according to the two time stamps. Accordingly, the displacement during the execution of the voice service V1 refers to the displacement occurring between the two time stamps.

For example, if the terminal 100 is a called terminal, the execution duration of the voice service V1 may refer to a time difference between a time when the called terminal rings and a time when the phone is hung up. The terminal 100 may record a time stamp of the moment when the called terminal rings and a time stamp of the moment when the phone is hung up, and obtain the execution duration of the voice service V1 according to the two time stamps. Accordingly, the displacement during the execution of the voice service V1 refers to the displacement occurring between the two time stamps.

For example, if the terminal 100 is a calling terminal, the execution duration of the voice service C1 may refer to a time difference between a time when the calling terminal initiates dialing and a time when the phone is hung up. The terminal 100 may record a timestamp of a time when dialing is initiated and record a timestamp of a time when the phone is hung up, and obtain an execution duration of the voice service V1 according to the two timestamps. Accordingly, the displacement during the execution of the voice service V1 refers to the displacement occurring between the two time stamps.

In one illustrative example, condition C1 may include condition C15, condition C15 being that the duration of execution of voice service V1 is less than a duration threshold. The speed threshold may be empirically or experimentally preset and may be, for example, 30 minutes. Terminal 100 before performing voice service V1, terminal 100 is within radio coverage provided by the 5G access network device. The coverage area of the wireless network signal of the 5G access network device is smaller, and particularly, the coverage area of the 5G wireless access network is not comprehensive enough in the early stage and even the middle stage of deployment of the 5G mobile communication system. If the call duration of the voice service V1 is long, the terminal 100 may leave the coverage of the 5G radio access network when the voice service V1 ends, so that the attempt to access the 5G radio access network fails. If the call duration of the voice service V1 is short, the terminal 100 is in coverage of the 5G radio access network with a high probability when the voice service V1 ends, and therefore, it is necessary to induce the network side to issue a different system measurement control message. The execution duration of the voice service V1 may be described with reference to the previous example, and will not be described herein.

In one illustrative example, condition C1 may include condition C16, condition C16 being that terminal 100 is not in an evolved universal terrestrial radio access network (evolved universal terrestrial radio access network, E-UTRAN) -NR dual connectivity (E-UTRA-NR dual connectivity, EN-DC) state.

The 3GPP release 15 defines a dual connectivity (dual connectivity, DC) framework for long term evolution (long term evolution, LTE) and new radio, NR, including EN-DC architecture. The EN-DC architecture is a Non-independent Networking (NSA) network architecture. The EN-DC architecture does not need to add a 5G core network, only needs to add a 5G base station, cooperates with the existing 4G base station, and provides 5G+4G joint access for the terminal, namely the terminal can reside in a 4G cell and a 5G cell at the same time. Under the EN-DC architecture, a control plane takes a 4G base station as a main node and a 5G base station as an auxiliary node. Wherein the 4G base station as a primary node may be referred to as MeNB (master eNB) and the 5G base station as a secondary node may be referred to as SgNB (secondary gNB). The 4G cell may be referred to as a master cell (master cell) and the 5G cell may be referred to as a secondary cell (secondary cell). It should be noted that the 5G base station in the EN-DC architecture is not the access network device 300 shown in fig. 1. The access network device 300 shown in fig. 1 refers to a 5G access network under a stand-alone networking architecture.

When the 4G base station to which the EPS of the terminal 100 falls is a 4G base station in the EN-DC architecture and the terminal 100 has EN-DC capability, it is possible for the 4G base station to add a secondary cell, i.e., a 5G cell, to the terminal 100. The specific adding process can be shown in fig. 9, and specifically includes the following steps.

901. The MeNB sends an addition request (addition request) from the SgNB to the SgNB.

902. The SgNB adds a request acknowledgement message to the MeNB (addition request acknowledge).

903. The MeNB sends a radio resource control (radio resource control, RRC) connection reconfiguration (connection reconfiguration) request to the terminal.

904. The terminal sends an RRC reconfiguration complete (connection reconfiguration complete) message to the MeNB.

905. The MeNB sends a SgNB reconfiguration complete (reconfiguration complete) message to the SgNB.

906. A random access procedure (random access procedure) is performed between the terminal and the SgNB.

907. The MeNB sends a SgNB state transition (status transfer) to the SgNB.

908. The MeNB sends a data transfer (data forwarding) to the SgNB.

A path update procedure (path update procedure) is performed between the MeNB and the mobility management entity (mobility management entity, MME). The method comprises the following steps of:

909. the MeNB sends an evolved radio access bearer (evolved radio access bearer, E-RAB) modification indication (modification indication) to the MME.

910. The MME sends a bearer modification (bearer modication) request to a serving gateway (S-GW).

911. The MeNB sends an end marker packet to the SgNB (end marker packet).

912. The MME sends an E-RAB modification confirm (modification confirm) message to the MeNB.

Wherein the MME and S-GW are network devices in a 4G core network (evolved packet core, EPC).

In general, when the terminal 100 performs a high throughput data service, the 4G base station adds a 5G cell to the terminal 100, and brings the terminal 100 into an EN-DU state. In order to avoid the impact on the high throughput data traffic, the terminal 100 may determine whether the terminal 100 is in the EN-DU state before transmitting the measurement report to the network side.

It is possible to determine whether a 5G RRC link exists between the terminal 100 and the network side. If there is also a 5G RRC link between the terminal 100 and the network side, it is determined that the terminal 100 is in the EN-DC state.

The scheme of judging whether or not there is a 5G RRC link between the terminal 100 and the network side is similar to the scheme of judging whether or not there is a 4G RRC link between the terminal 100 and the network side. Specifically, as is clear from the scheme shown in fig. 9, when adding a 5G cell to the terminal 100, it is necessary to perform a random access procedure between the terminal and the SgNB. The RRC link between the terminal 100 and the SgNB, i.e., the RRC link of 5G, is established through a random access procedure. If the terminal 100 does not receive the 5G RRC connection release message issued by the MeNB, a 5G RRC link still exists between the terminal 100 and the network side, and it may be determined that the terminal 100 is in the EC-DC state, that is, the terminal 100 does not satisfy the condition C16. If there is no RRC link of 5G between the terminal 100 and the network side, the terminal 100 is not in ED-DC state, and the condition C16 is satisfied.

In one illustrative example, condition C1 may include condition C17, condition C17 being that terminal 100 is not in test mode. By way of example, the test mode may refer to a mode in which a handset designer or network operator tests a terminal, but the terminal enters. Typically, a handset designer or network operator uses a special test subscriber identity module (subscriber identification module, SIM) card to test the terminal. Therefore, the terminal 100 can determine whether it is in the test mode through information carried in the SIM card it is installed. If the terminal 100 is in the test mode, the terminal does not satisfy the condition C17. If the terminal is not in the test mode, the terminal satisfies the condition C17.

In one illustrative example, the condition C1 may include any two or more of the conditions C11, C12, C13, C14, C15, C16, C17, and then the terminal 100 satisfying the condition C1 specifically means that the terminal 100 satisfies the two or more items simultaneously.

In the above, the conditions to be satisfied before the terminal 100 sends the measurement report E1 to the network side are described as examples, but the conditions are not limited thereto, and other conditions may be set, which are not listed here.

It can be appreciated that the network side may normally issue the inter-system measurement control message. The network side normally issues the inter-system measurement control message may refer to that the network side issues the inter-system measurement control message under the condition that the network side is not induced by the measurement report E1 provided by the embodiment of the present application. For example, when the end of the voice service dropped by the EPS is a condition for triggering the network side to issue the inter-system measurement control message, after the end of the voice service dropped by the EPS, the network side may issue the inter-system measurement control message without receiving the measurement report E1.

In some embodiments, to avoid collision with the network side normally issuing the inter-system measurement control messages. At the end of the voice service V1, the terminal 100 may start the timer D1. If the timer D1 starts counting and the timer D1 times out, the terminal 100 does not receive the inter-system measurement control message, and the terminal 100 may send the measurement report E1 to the network side. Since the timer D1 is a timer set to avoid collision with the network side normally issuing the inter-system measurement control message, the timer D1 may also be referred to as a guard timer or a fast back NR (5G) guard timer.

In one illustrative example, the duration of timer D1 may be determined by returning 5G duration big data. The return 5G duration may be a duration of a time period between an end time of the voice service and a time of re-accessing the 5G radio access network. The distribution of each duration in the 5G duration big data can be calculated. Specifically, the duration from the end of the voice service dropped by the EPS to the return to 5G of the existing terminal can be collected, and the return 5G duration big data can be obtained. The duration of the timer D1 may be determined according to the distribution of the durations in the returned 5G duration big data. For example, the duration of the timer D1 may be set as the duration of the time period of which probability is maximum.

In one illustrative example, the duration of the timer D1 may be preset empirically or experimentally, for example, may be a duration of 2 s.

In some embodiments, in the case where the terminal 100 has not received the foreign system control message when the condition C1 is satisfied and the timer D1 expires, the terminal 100 transmits the measurement report E1 to the network side.

With continued reference to fig. 4, in some embodiments, if the network side, such as the access network device 200, turns on the function of issuing the inter-system measurement control message, when receiving the measurement report E1 sent by the terminal 100, step 407 may be performed in response to the measurement report E1, and the inter-system measurement control message is sent to the terminal 100.

Illustratively, as described above, the measurement report E1 includes the measurement identity of the event A2 (or the event A3), and the access network device 200 may identify the measurement report E1 as the measurement report of the event A2 (or the event A3) according to the measurement identity of the event A2 (or the event A3), so that it may be determined or considered that the signal quality of the serving cell of the terminal 100 is lower than the threshold value (or that the signal quality of the system neighbor of the terminal 100 is higher than the signal quality of the serving cell), and may transmit the inter-system measurement control message to the terminal 100.

Illustratively, as described above, the format and manner of generation of the measurement report E1 are the same as or similar to the format and manner of generation of the measurement report of event A2 (or event A3) specified in the 3GPP protocol. Accordingly, when the access network device 200 receives the measurement report E1, it may determine or consider that the signal quality of the serving cell of the terminal 100 is lower than the threshold value (or that the signal quality of the system neighbor of the terminal 100 is higher than the signal quality of the serving cell), so that the inter-system measurement control message may be transmitted to the terminal 100.

With continued reference to fig. 4, when the terminal 100 receives the inter-system measurement control message, step 409 may be performed to measure the inter-system network in response to the inter-system measurement control message. It can be understood that, in the network system shown in fig. 1, the 5G mobile communication system is a different system from the 4G mobile communication system. In the case where the network where the terminal 100 is currently resident is a 4G network, the measurement of the heterogeneous system network may specifically refer to the measurement of a 5G network. The terminal 100 may report the measurement result to the access network device 200 so that the access network device 200 instructs the terminal 100 to access the 5G network according to the measurement result.

The terminal 100 may also perform step 411 to send a measurement report E2 to the access network device 200.

In some embodiments, the inter-system measurement control message may be a measurement control message of event B1 (event B1), where event B1 refers to when the signal quality of the inter-system neighbor is higher than the threshold value (inter RAT neighbour becomes better than threshold), the terminal 100 reports a measurement report E2 to the access network device 200, where the measurement report E2 is used to report the signal quality of the inter-system neighbor to the access network device 200, so that the access network device 200 indicates that the terminal accesses to the inter-system network according to the signal quality of the inter-system neighbor in the measurement report E2. The inter-system network may be a 5G network, and the inter-system neighbor cell may be a 5G cell.

Specifically, the present invention relates to a method for manufacturing a semiconductor device. The terminal 100 may measure signal quality (for example, RSRP or RSRQ or SINR or RSSI) on the 5G frequency band in response to the measurement control message of the event B1, and the signal quality of the neighboring cell of the different system with the signal quality higher than the threshold value is carried in a measurement report and reported to the access network device 200. Reference may be made specifically to 3GPP related protocols, which are not described in detail herein.

With continued reference to fig. 4, in some embodiments, the access network device 200 may instruct the terminal 100 to access the 5G radio access network by redirecting or switching.

For example, if the access network 200 instructs the terminal 100 to access the 5G radio access network in a redirection manner, the access network device 200 may send an RRC release message to the terminal 100, and carry indication information in the RRC release message, where the indication information is used to indicate a frequency point of the 5G cell with a signal quality higher than a threshold value. The terminal 100 may perform 5G cell search and access on the frequency point indicated by the indication information carried by the RRC release message, and camp on the 5G cell. The access of the 5G cell may be achieved through a random access procedure, which may be described above and will not be described herein.

For example, if the access network 200 indicates that the terminal 100 accesses the 5G radio access network by redirecting, the access network device 200 may determine, for the terminal 100, a target cell according to the 5G cell in the measurement report of the event B1, where the target cell is a cell with a signal quality higher than the threshold value. The access network device 200 may send an RRC connection reconfiguration (RRC connection reconfiguration) message to the terminal 100. The RRC connection reconfiguration message includes the physical cell identity (identity) of the target cell. The terminal 100 may access the target cell through a random access procedure, thereby accessing the 5G network.

Referring to fig. 10, when the terminal 100 accesses a 5G cell, a wireless network icon in a status bar of the terminal 100 may become a 5G network icon 501.

In some embodiments, even if the terminal 100 transmits the measurement report E1 to the access network apparatus 200, it is possible that the terminal 100 cannot receive the inter-system measurement control message. For example, the access network apparatus 200 does not turn on a function of issuing the foreign system measurement control message, and thus, the access network apparatus 200 does not issue the foreign system measurement control message in response to the measurement report E1 after receiving the measurement report E1. For this, the terminal 100 may start the timer D2 when transmitting the measurement report E1 to the access network apparatus 200. If the timer D2 starts to count up, and the timer D2 times out, the terminal 100 has not received the inter-system measurement control message, and the terminal 100 may start to return to the 5G procedure autonomously. The following will describe in detail.

In one illustrative example, the duration of timer D2 may be determined by receiving duration big data of a heterogeneous system measurement control message. The duration of receiving the inter-system measurement control message may be the duration of a time period between the transmission time of the measurement report of event A2 (and/or event A3) and the reception time of the inter-system measurement control message. Specifically, the length of time that the existing terminal experiences from sending the measurement report of the event A2 (and/or the event A3) to receiving the inter-system measurement control message to the network side can be collected, so as to obtain the length big data of the inter-system measurement control message. In other words, the distribution of the respective durations in the duration big data of the reception of the inter-system measurement control message can be calculated. The duration of the timer D2 may be determined according to the distribution of the durations in the duration big data of the received inter-system measurement control message. For example, the duration of the timer D2 may be set as the duration of the time period of which probability is largest.

In one illustrative example, the duration of the timer D2 may be preset empirically or experimentally, for example, may be a duration of 1 s.

In one illustrative example, if the timer D2 expires from the timer D2, the terminal 100 has not received the inter-system measurement control message. The terminal 100 residing in the 4G radio access network may actively measure the network signal on the 5G frequency band, i.e. the terminal 100 residing in the 4G radio access network may autonomously measure the network signal on the 5G frequency band without indication information (e.g. a foreign system measurement control message) on the network side. For example, the terminal 100 may search for a cell on the 5G full band and measure the signal quality of the searched cell. For example, RSRP, RSRQ, SINR, or RSSI of a cell may be measured.

If a cell is searched in the 5G frequency band, namely, a 5G cell is searched, and the signal quality of the 5G cell is higher than a threshold value. The terminal 100 may perform a local release RRC link procedure and return to the idle state. That is, the terminal 100 may autonomously release the RRC link without receiving the RRC release message issued by the network side. The terminal 100 in an idle state may attempt to access the 5G cell through a random access procedure. The random access procedure may be described above, and will not be described in detail here. The threshold value may refer to the 3GPP protocol and will not be described in detail herein.

Illustratively, the terminal 100 may succeed in accessing the 5G cell successfully. When the terminal 100 successfully accesses the 5G cell, as shown in fig. 10, the wireless network icon in the status bar of the terminal 100 may become the 5G network icon 501.

For example, the terminal 100 may fail to access the 5G cell, for example, in the random access procedure, when the timer expires, the terminal 100 does not receive the contention resolution result sent by the network side (for example, the access network device 300), which indicates that the access to the 5G cell fails. When the terminal 100 fails to access the 5G cell, the terminal 100 may transmit an RRC connection reestablishment request to the access network apparatus 200 (RRC connection reestablishment request). The access network device 200 transmits an RRC connection reestablishment (RRC connection reestablishment) message to the terminal 100 in response to the RRC connection reestablishment request. The terminal 100 may transmit an RRC connection reestablishment complete (RRC connection reestablishment complete) message to the access network device 200. Thus, the terminal 100 can re-establish the RRC link between the terminal 100 and the access network device 200 in case of failure in accessing the 5G cell, so that the original data service can be continued through the 4G network.

In some embodiments, if no cell is searched on the 5G frequency band, or the signal quality of the searched cell does not meet the threshold value. The terminal 100 continues to maintain the RRC link with the access network device 200.

According to the network access method provided by the embodiment of the application, after the EPS fallback voice service is finished, the measurement report can be actively sent to the network side to induce the network side to issue the different system measurement control message, so that the flow of the terminal to quickly return to the 5G network can be quickly opened, the terminal can quickly return to the 5G network, and the user network experience is improved.

The embodiment of the application provides another network access method. The network access method may be performed by the terminal 100. The network access method is specifically as follows.

When the voice service V1 ends, it may be judged whether the terminal 100 satisfies the condition C1. Reference is specifically made to the above description, and no further description is given here.

If the terminal 100 satisfies the condition C1, the terminal 100 may start the timer D1.

If the timer D1 times out, the terminal 100 does not receive the inter-system measurement control message. I.e., from the start of the timer D1 to the expiration of the timer D1, the terminal 100 does not receive the inter-system measurement control message. The terminal can search the network on the 5G frequency band and measure the signal quality of the network. The signal quality may be RSPR, RSRQ, SINR, or RSSI.

If a 5G cell is searched and the signal quality of the 5G cell satisfies the threshold, the terminal 100 may locally release the RRC link of 4G and attempt to access the 5G cell whose signal satisfies the threshold.

Next, in a specific example, the network access method is described by way of example.

Referring to fig. 11, the terminal 100 may include a talk module, an LTE access layer module, and an NR access layer module. The LTE access layer module may also be referred to as a 4G access layer module, which may implement related functions according to a radio resource control layer protocol of LTE (4G). The NR access layer module may also be referred to as a 5G access layer module, which may implement related functions according to a radio resource control layer protocol of NR (5G). The call module may be configured to detect an end of a voice service and send a voice service end notification to the LTE access layer module.

For example, as shown in fig. 11, the call module, the LTE access layer module, and the NR access layer module may be modules or functional entities in a modem (modem) of the terminal 100.

As shown in fig. 11, when the terminal 100 resides in the 5G radio access network, if there is a voice service to be executed by the terminal 100, EPS fallback is performed, the terminal falls back from the 5G radio access network to the 4G radio access network, and then a long term evolution-term evolution (VOLTE) call is performed through the 4G radio access network. That is, through EPS fallback, an RRC link is established between the LTE access layer module and the access network device 200, and data transmission of voice service is performed through the RRC link.

When the voice service ends, the call module may send a VOLTE call end notification to the LTE access layer module, where the VOLTE call end notification may include a "volte_ END, callStartInNrFlag =true" field.

The LTE access layer module may determine that the terminal 100 is in a connected state under the 4G network, i.e., may determine that an RRC link exists between the LTE access layer module and the access network device 200. Then, the LTE access layer module may determine whether the terminal 100 satisfies the condition C1, which may be specifically described above, and will not be described herein. If the terminal 100 satisfies the condition C1, the LTE access layer module may start the timer D1.

If the timer D1 times out, the terminal 100 does not receive the inter-system measurement control message. The LTE access layer module may send a network search request to the NR access layer module.

And the NR access layer module is used for searching the 5G cell on the 5G frequency band in response to the network searching request. If the 5G cell is searched, and the signal quality of the 5G cell is higher than the threshold value. And the NR access layer module sends a network searching success message to the LTE access layer module.

The LTE access layer module may actively release the RRC link of LTE (4G), i.e., release the RRC link between the LTE access layer module and the access network device 200, in response to the network search success message.

The LTE access layer module may send a link release success message to the NR access layer module. And the NR access layer module can attempt to access the 5G cell after receiving the link release success message. In particular, the access to the 5G cell may be attempted by a random access procedure.

In some embodiments, the NR access layer module may fail to access the 5G cell, for example, in a random access procedure, when the timer expires, the NR access layer module does not receive the contention resolution result sent by the access network device 300, which indicates that the access to the 5G cell fails. When the NR access layer module fails to access the 5G cell, the LTE access layer module may send an RRC connection reestablishment request to the access network device 200. The access network device 200 transmits an RRC connection reestablishment message to the LTE access layer module in response to the RRC connection reestablishment request. The LTE access layer module may send an RRC connection re-establishment complete message to the access network device 200. Therefore, the NR access layer module can reestablish the RRC link between the LTE access layer module and the access network equipment 200 under the condition of failure in accessing the 5G cell, so that the original data service can be continuously carried out through the 4G network.

In some embodiments, if no cell is searched on the 5G frequency band, or the signal quality of the searched cell does not meet the threshold value. The LTE access layer module continues to maintain the RRC link between it and the access network device 200.

By the network access method provided by the embodiment of the application, the terminal can actively search the 5G frequency band under the condition that the terminal does not receive the inter-system measurement control message in the preset time period after the EPS fallback voice service is finished. When the 5G cell is searched and the signal quality of the 5G cell meets the threshold value, the RRC link of the LTE can be locally released and the terminal is tried to access the 5G cell, so that the terminal can quickly return to the 5G network, and the user network experience is improved.

Referring to fig. 12, an embodiment of the present application provides a terminal 1200, where the terminal 1200 may perform the operations performed by the terminal in the embodiments of the methods shown in fig. 4 or fig. 11. Wherein terminal 1200 can include a processor 1210, a memory 1220, and a transceiver 1230. The memory 1220 has stored therein instructions that can be executed by the processor 1210. When executed by processor 1210, terminal 1200 may perform the operations performed by the terminal in the various method embodiments illustrated in fig. 4 or 11 described above. In particular, processor 1210 may perform data processing operations and transceiver 1230 may perform data transmission and/or reception operations.

Referring to fig. 13, an embodiment of the present application provides a chip system 1300 that may be applied to a terminal. The chip system 1300 includes: a processor 1310 and an interface circuit 1320. The processor 1310 is connected to the interface circuit 1320 for performing the operations performed by the terminal in the method embodiments shown in fig. 4 or fig. 11.

In some embodiments, the chip system 1300 also includes a memory 1330. Stored in memory are instructions that are executable by the processor 1310. The instructions, when executed by processor 1310, may cause system-on-chip 1300 to perform the operations performed by the terminal in the various method embodiments illustrated in fig. 4 or 11 described above.

It is to be appreciated that the processor in embodiments of the present application may be a central processing unit (central processing unit, CPU), but may also be other general purpose processors, digital signal processors (digital signal processor, DSP), application specific integrated circuits (application specific integrated circuit, ASIC), field programmable gate arrays (field programmable gate array, FPGA) or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general purpose processor may be a microprocessor, but in the alternative, it may be any conventional processor.

The method steps in the embodiments of the present application may be implemented by hardware, or may be implemented by a processor executing software instructions. The software instructions may be comprised of corresponding software modules that may be stored in random access memory (random access memory, RAM), flash memory, read-only memory (ROM), programmable ROM (PROM), erasable programmable PROM (EPROM), electrically erasable programmable EPROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may 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 loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted across a computer-readable storage medium. The computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)), or wireless (e.g., 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, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a Solid State Disk (SSD)), or the like.

It will be appreciated that the various numerical numbers referred to in the embodiments of the present application are merely for ease of description and are not intended to limit the scope of the embodiments of the present application.

Claims

1. The network access system is characterized by comprising 4G access network equipment, 5G access network equipment and a terminal; wherein, the liquid crystal display device comprises a liquid crystal display device,

the terminal is connected to 5G access network equipment, the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR;

when the terminal performs voice service, the 5G access network device is used for indicating that the terminal is connected to the 4G access network device through an EPS fallback program so that the terminal performs the voice service through the 4G access network device;

the terminal is used for receiving the hang-up operation and responding to the hang-up operation to end the voice service; or the terminal is used for receiving a hang-up instruction from the 4G access network equipment and ending the voice service in response to the hang-up instruction;

when the terminal and the 4G access network equipment keep RRC connection, the terminal is used for actively sending a measurement report to the 4G access network equipment in response to the end of the voice service, the measurement report is used for triggering the 4G access network equipment to send different system measurement control information to the terminal, and the different system measurement control information is used for triggering the terminal to be reconnected to the 5G access network equipment.

2. The system of claim 1, wherein the 4G access network device is configured to send a foreign system measurement control message to the terminal in response to the measurement report, the foreign system measurement control message being configured to trigger the terminal to measure signal quality of a foreign system neighbor.

3. The system of claim 1, wherein the terminal for actively sending measurement reports to the 4G access network device comprises:

and when the terminal does not receive the inter-system measurement control message in a first time period, the terminal is used for actively sending the measurement report to the 4G access network equipment, wherein the first time period is a time period started when or after the voice service is ended.

4. A system according to any of claims 1-3, wherein the terminal being configured to actively send measurement reports to the 4G access network device comprises:

the terminal is used for determining that the terminal meets a first condition; wherein the first condition includes at least one of:

the method comprises the steps that delay sensitive data service is not executed, the voice service is not an emergency call service, the voice service is not in an emergency call callback mode, the execution duration of the voice service is smaller than a first threshold value, the moving speed of the terminal is smaller than a second threshold value during the execution of the voice service, the voice service is not in an evolution type unified land wireless access network-new air interface dual-connection EN-DC state, and the voice service is not in a test mode;

The terminal is used for actively sending the measurement report to the 4G access network equipment.

5. A system according to any of claims 1-3, wherein the terminal is further configured to actively measure the signal quality of the first network provided by the 5G access network device when no inter-system measurement control message is received;

the terminal is further configured to actively disconnect the RRC connection between the terminal and the 4G access network device and attempt to access the first network when the signal quality of the first network is above a first threshold.

6. The system of claim 5, wherein the terminal is further configured to send an RRC connection reestablishment request to the 4G access network device to reestablish the RRC connection between the terminal and the 4G access network device when the terminal fails to attempt to access the first network.

7. A network access method, comprising:

the terminal is connected to 5G access network equipment, wherein the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR;

when the terminal performs voice service, the terminal is connected to 4G access network equipment to perform the voice service through the 4G access network equipment, wherein the terminal is accessed to the 4G access network equipment through the indication of the 5G access network equipment, and the indication is the indication of the 5G access network equipment through an EPS fallback program;

The terminal receives a hang-up operation and responds to the hang-up operation to end the voice service; or the terminal receives a hang-up instruction from the 4G access network equipment and responds to the hang-up instruction to end the voice service;

when the terminal and the 4G access network equipment keep RRC connection, the terminal responds to the end of the voice service and actively transmits a measurement report to the 4G access network equipment, wherein the measurement report is used for triggering the 4G access network equipment to transmit different system measurement control information to the terminal, and the different system measurement control information is used for triggering the terminal to be reconnected to the 5G access network equipment.

8. The method of claim 7, wherein the method further comprises:

the terminal receives a different system measurement control message from the 4G access network device, wherein the different system measurement control message is a message sent by the 4G access network device in response to the measurement report;

and the terminal responds to the inter-system measurement control message and measures the signal quality of the inter-system neighbor cell.

9. The method of claim 7, wherein the terminal actively transmitting a measurement report to the 4G access network device comprises:

And when the terminal does not receive the inter-system measurement control message in a first time period, the terminal actively transmits the measurement report to the 4G access network equipment, wherein the first time period is a time period started when or after the voice service is ended.

10. The method according to any of claims 7-9, wherein the terminal actively sending a measurement report to the 4G access network device comprises:

the terminal determines that the terminal meets a first condition; wherein the first condition includes at least one of:

11. The method according to any one of claims 7-9, further comprising:

When the terminal does not receive the inter-system measurement control message, the terminal actively measures the signal quality of a first network provided by the 5G access network equipment;

and when the signal quality of the first network is higher than a first threshold, the terminal actively disconnects the RRC connection between the terminal and the 4G access network equipment and tries to access the first network.

12. The method of claim 11, wherein the method further comprises:

and when the terminal fails to attempt to access the first network, sending an RRC connection reestablishment request to the 4G access network equipment so as to reestablish the RRC connection between the terminal and the 4G access network equipment.

13. A terminal, comprising: a processor, a memory, a transceiver;

the memory is used for storing computer instructions;

when the terminal is running, the processor executes the computer instructions to cause the terminal to perform:

the method comprises the steps of connecting to 5G access network equipment, wherein the 5G access network equipment does not support VoNR, and/or the 5G core network equipment corresponding to the 5G access network equipment does not support VoNR;

when the terminal performs voice service, connecting to 4G access network equipment to perform the voice service through the 4G access network equipment, wherein the terminal accesses to the 4G access network equipment through the indication of the 5G access network equipment, and the indication is the indication of the 5G access network equipment through an EPS fallback program;

Receiving a hang-up operation, and ending the voice service in response to the hang-up operation; or receiving a hang-up instruction from the 4G access network equipment, and ending the voice service in response to the hang-up instruction;

and when the terminal and the 4G access network equipment keep RRC connection, actively sending a measurement report to the 4G access network equipment in response to the end of the voice service, wherein the measurement report is used for triggering the 4G access network equipment to send inter-system measurement control information to the terminal, and the inter-system measurement control information is used for triggering the terminal to be reconnected to the 5G access network equipment.

14. The terminal of claim 13, wherein the processor executes the computer instructions such that the terminal further performs:

receiving a inter-system measurement control message from the 4G access network device, the inter-system measurement control message being a message sent by the 4G access network device in response to the measurement report;

and measuring the signal quality of the neighboring cell of the different system in response to the measurement control message of the different system.

15. The terminal of claim 13, wherein the processor executes the computer instructions such that the terminal further performs:

And when the terminal does not receive the inter-system measurement control message in a first time period, the measurement report is actively sent to the 4G access network equipment, wherein the first time period is a time period started when or after the voice service ends.

16. The terminal of any of claims 13-15, wherein the processor executes the computer instructions such that the terminal further performs:

determining that the terminal meets a first condition; wherein the first condition includes at least one of:

and actively sending the measurement report to the 4G access network equipment.

17. The terminal of any of claims 13-15, wherein the processor executes the computer instructions such that the terminal further performs:

When the terminal does not receive the inter-system measurement control message, measuring the signal quality of a first network provided by the 5G access network equipment;

and when the signal quality of the first network is higher than a first threshold, actively disconnecting the RRC connection between the terminal and the 4G access network equipment, and attempting to access the first network.

18. The terminal of claim 17, wherein the processor executes the computer instructions such that the terminal further performs:

19. A chip system, comprising: a processor and interface circuit;

the processor is connected to the interface circuit for executing instructions to cause a terminal on which the chip system is mounted to perform the method of any of claims 7-12.

20. A computer storage medium comprising computer instructions which, when run on a terminal, cause the terminal to perform the method of any of claims 7-12.