WO2023207153A1

WO2023207153A1 - Voice call method and apparatus

Info

Publication number: WO2023207153A1
Application number: PCT/CN2022/140478
Authority: WO
Inventors: 陈拴锋; 罗飞; 曾伟
Original assignee: 荣耀终端有限公司
Priority date: 2022-04-29
Filing date: 2022-12-20
Publication date: 2023-11-02
Also published as: CN115551111B; CN115551111A

Abstract

The embodiments of the present application relate to the field of terminals, and provided thereby are a voice call method and apparatus, which can solve the problem of continuous called failure of EPS fallback and improve user experience. The present application is used for a communications system comprising a first terminal device and a second terminal device, the second terminal device residing in a 5G SA network. The method comprises: the first terminal device initiates a call to the second terminal device; the second terminal device initiates EPS fallback to establish a voice call with the first terminal device; after the second terminal device falls back to an LTE network, it is determined that EPS fallback fails; at such a time, the second terminal device starts a first timer, and the second terminal device resides in the LTE network during the starting period of the first timer, such that the call from the first terminal device is subsequently directly received in the LTE network, and EPS fallback does not need to be continuously initiated, thereby avoiding the problem of continuous called failure of EPS fallback.

Description

A voice calling method and device

This application claims priority to the Chinese patent application submitted to the State Intellectual Property Office on April 29, 2022, with the application number 202210468848.1 and the invention title "A voice calling method and device", the entire content of which is incorporated into this application by reference. middle.

Technical field

The present application relates to the field of communications, and in particular, to a voice calling method and device.

Background technique

Under the fifth generation (5th generation, 5G) mobile communication system standalone (SA) network, the call plan (voice plan) can use the evolved packet system fallback (EPS Fallback) to carry voice. EPS Fallback is a solution for falling back from the fifth generation (5th generation, 5G) mobile communication system network to the fourth generation (4th generation, 4G) mobile communication system network. EPS Fallback voice services carry voice services through the 4G network data domain. That is, when the terminal device working on the 5G SA network initiates a voice call or has an incoming voice call, the network switches the 5G terminal to the 4G network through the handover process, and the voice over long term evolution (VoLTE) of the 4G network is used. ) technology provides voice services.

The EPS Fallback process can include RRC establishment, 4G cell camping after redirection, tracking area update (TAU)/attachment (ATTACH) process, voice bearer activation under 4G, session initialization protocol (session initiation protocol, SIP) interaction Wait for the sub-process, any abnormality in any sub-process will cause the call establishment to fail. After the call establishment fails, the called terminal device can return to the 5G network from the 4G network based on the Fast Return mechanism.

When call establishment fails, the calling terminal device usually performs automatic redialing (redial), or the user can manually redial to reinitiate the call. Since the called terminal equipment has returned to 5G through the Fast Return mechanism at this time, the called terminal equipment needs to perform the EPS Fallback process again. The called terminal equipment may have continuous EPS Fallback called failure problems, which affects the user experience.

Contents of the invention

In view of this, this application provides a voice calling method and device, which can solve the problem of continuous EPS Fallback called failure and improve user experience.

In the first aspect, this application provides a voice call method, which is applied to a communication system including a first terminal device and a second terminal device. The second terminal device resides in a fifth-generation mobile communication system independent networking 5G SA network; One terminal device initiates a call to the second terminal device; the second terminal device initiates the Evolved Packet System Fallback voice bearer EPS Fallback to establish a voice call with the first terminal device; after the second terminal device falls back to the Long Term Evolution LTE network, it is determined that the EPS Fallback fails; The second terminal device starts the first timer, and during the period of starting the first timer, the second terminal device resides on the LTE network.

Based on the method provided by the embodiments of this application, when it is determined that the EPS Fallback call establishment fails, the second terminal device (called terminal device) can start the first timer (Slow Return timer). Before the Slow Return timer expires, the called terminal device will not return to the 5G network through reselection or handover. That is, the called terminal device can be allowed to stay on 4G LTE for a longer period of time. In this way, when the calling terminal device (first terminal device) redials, the called terminal device can directly establish a call with the calling terminal device on 4G LTE, increasing the possibility of successful call establishment. Since the called terminal device has already resided on 4G LTE, there is no need to initiate EPS Fallback again to establish a call with the calling terminal device. This solves the problem of continuous EPS Fallback called failures encountered by users and improves user experience.

In a possible implementation, the method further includes: before the first timer times out, the second terminal device establishes a VOLTE voice call with the first terminal device. Before the first timer times out, the called terminal device remains in 4G LTE. In this way, when the calling terminal device (first terminal device) redials, the called terminal device can directly establish a VOLTE voice call with the first terminal device on 4G LTE, increasing the possibility of successful call establishment.

In a possible implementation, after the VOLTE voice call established between the second terminal device and the first terminal device ends, the second terminal device re-camps on the 5G SA network. The second terminal device returns to a higher standard network (5G SA network) to stay on the network, and can get better and more comprehensive services.

In a possible implementation, starting the first timer by the second terminal device includes: if the second terminal device meets a preset condition, starting the first timer; wherein the preset condition includes: the second terminal device is not turned on. In the default application program, the second terminal device does not turn on the game mode, and/or the second terminal device is in a screen-off state. It is understandable that when the called terminal device meets the preset conditions, that is, when the preset application is not opened, the game mode or performance mode is not turned on, and/or the screen is off, the requirements for network quality and data transmission rate are low. , can reside on a lower standard network (for example, 4G network) to provide services to users. At this time, turning on the first timer (Slow Return timer) will not affect the normal operation of the called terminal equipment, and can improve the call completion rate of the called terminal equipment. When the called terminal device does not meet the preset conditions, for example, the called terminal device opens a preset application, turns on game mode or performance mode, or is in a bright screen state, it has higher requirements for data transmission rate and network quality. , It is necessary to reside on a high-standard network (for example, 5G network) as soon as possible to provide users with smoother services. At this time, you can disable the Slow Return timer to avoid affecting the normal operation of the called terminal device.

In a possible implementation, the reasons for EPS Fallback failure include at least one of the following: the signal quality of the LTE cell corresponding to the designated frequency point of the network is lower than the preset threshold and the signal quality of the neighboring cells of the LTE cell is higher than the preset threshold, tracking The zone update TAU duration is longer than the preset duration, resulting in resource reservation failure, session initialization protocol SIP message transmission failure, and the second terminal device receiving error code 503 indicating that the call was abnormally released.

In a possible implementation, during the start of the first timer, the second terminal device suppresses 5G SA, or restricts reselection and handover to 5G. In this way, the second terminal device can stay on the LTE network during the start of the first timer, so that when the calling terminal device (first terminal device) redials, the called terminal device can directly communicate with the first terminal in 4G LTE The device establishes a VOLTE voice call, increasing the possibility of the call being successfully established.

In a possible implementation, the method further includes: if the second terminal device determines that EPS Fallback is successful, the second terminal device establishes a voice call with the first terminal device; after the call between the second terminal device and the first terminal device ends, the second terminal device The second terminal device re-resides in the 5G SA network. The second terminal device returns to a higher standard network (5G SA network) to stay on the network, and can get better and more comprehensive services.

In a possible implementation, re-camping the second terminal device to the 5G SA network includes: the second terminal device starts a second timer, and before the second timer times out, receives the first wireless resource issued by the network device. Control the release of the RRC release message. The first RRC release message carries the new wireless NR frequency point information. The second terminal device searches the network based on the NR frequency point information and sets up the network to the 5G SA network; or before the second timer times out, the receiving network The second RRC release message sent by the device does not carry NR frequency point information, and the second terminal device returns to the 5G SA network based on the historical resident NR frequency point information; or after the second timer times out, if If the first RRC release message or the second RRC release message is not received, the second terminal device returns to the 5G SA network based on the historical resident NR frequency point information.

In the second aspect, this application provides a voice call method, which is applied to a communication system including a first terminal device and a second terminal device. The second terminal device resides in a fifth-generation mobile communication system independent networking 5G SA network; The second terminal device receives the call signaling corresponding to the call initiated by the first terminal device; the second terminal device initiates the Evolved Packet System Fallback voice bearer EPS Fallback to establish a voice call with the first terminal device; after the second terminal device falls back to the Long Term Evolution LTE network, It is determined that the EPS Fallback fails; the second terminal device starts the first timer, and during the start of the first timer, the second terminal device resides on the LTE network.

In a possible implementation, the method further includes: before the first timer times out, the second terminal device establishes a VOLTE voice call with the first terminal device.

In a possible implementation, after the VOLTE voice call established between the second terminal device and the first terminal device ends, the second terminal device re-camps on the 5G SA network.

In a possible implementation, starting the first timer by the second terminal device includes: if the second terminal device meets a preset condition, starting the first timer; wherein the preset condition includes: the second terminal device is not turned on. In the default application program, the second terminal device does not turn on the game mode, and/or the second terminal device is in a screen-off state.

In a possible implementation, during the activation of the first timer, the second terminal device suppresses 5G SA, or restricts reselection and handover to 5G.

In a possible implementation, the method further includes: if the second terminal device determines that EPS Fallback is successful, the second terminal device establishes a voice call with the first terminal device; after the call between the second terminal device and the first terminal device ends, the second terminal device The second terminal device re-resides in the 5G SA network.

In a possible implementation, re-camping the second terminal device to the 5G SA network includes: the second terminal device starts a second timer, and before the second timer times out, receives the first wireless resource issued by the network device. Control the release of the RRC release message. The first RRC release message carries the new wireless NR frequency point information. The second terminal device searches the network based on the NR frequency point information and sets up the network to the 5G SA network; or before the second timer times out, the receiving network The second RRC release message sent by the device does not carry the NR frequency point information. The second terminal device returns to the 5G SA network based on the historical resident NR frequency point information; or after the second timer times out, if If the first RRC release message or the second RRC release message is not received, the second terminal device returns to the 5G SA network based on the historical resident NR frequency point information.

In a third aspect, the present application provides a computer program product, which when the computer program product is run on a computer, causes the computer to execute the method described in any of the above aspects and any possible design manner thereof.

In a fourth aspect, the present application provides a computer-readable storage medium that includes computer instructions. When the computer instructions are run on the second terminal device (such as a mobile phone), the second terminal device is caused to execute the method described in the second aspect and any possible implementation thereof.

In a fifth aspect, embodiments of the present application provide a processing device, which includes a processor. The processor is coupled to a memory. The memory stores program instructions. When the program instructions stored in the memory are executed by the processor, the device implements the second step described above. Aspects and methods described in any possible design method. The device may be a second terminal device; or may be a component of the second terminal device, such as a chip.

In a sixth aspect, the present application provides a chip system, which includes one or more interface circuits and one or more processors. The interface circuit and the processor are interconnected through lines.

The above chip system can be applied to a second terminal device including a communication module and a memory. The interface circuit is configured to receive signals from the memory of the first terminal device and send the received signals to the processor, the signals including computer instructions stored in the memory. When the processor executes the computer instructions, the second terminal device can execute the method described in the second aspect and any possible design manner thereof.

In a seventh aspect, embodiments of the present application provide a communication system, including a first terminal device and a second terminal device. The first terminal device and the second terminal device respectively perform part of the steps and cooperate with each other to implement the above-mentioned first aspect. and any possible design method.

Description of the drawings

Figure 1 is a schematic flow chart provided by an embodiment of the present application;

Figure 2 is a schematic structural diagram of a communication system provided by an embodiment of the present application;

Figure 3 is a schematic structural diagram of a terminal device provided by an embodiment of the present application;

Figure 4 is another schematic flow diagram provided by an embodiment of the present application;

Figure 5 is a schematic display diagram provided by an embodiment of the present application;

Figure 6 is another display schematic diagram provided by an embodiment of the present application;

Figure 7 is another schematic flow diagram provided by an embodiment of the present application;

FIG. 8 is a schematic structural diagram of a chip system provided by an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Among them, in the description of this application, unless otherwise stated, "/" means that the related objects are an "or" relationship. For example, A/B can mean A or B; "and/or" in this application "It is just an association relationship that describes related objects. It means that there can be three relationships. For example, A and/or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. Among them, A ,B can be singular or plural. Furthermore, in the description of this application, unless otherwise specified, "plurality" means two or more than two. "At least one of the following" or similar expressions thereof refers to any combination of these items, including any combination of a single item (items) or a plurality of items (items). For example, at least one of a, b, or c can represent: a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, c can be single or multiple . In addition, in order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as “first” and “second” are used to distinguish identical or similar items with basically the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the number and execution order, and words such as "first" and "second" do not limit the number and execution order. At the same time, in the embodiments of this application, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "such as" in the embodiments of the present application is not to be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete manner that is easier to understand.

Currently, under the 5G SA network, the call plan can use EPS Fallback. EPS Fallback is a call solution (voice solution) that falls back from 5G to 4G. For example, as shown in Figure 1, the EPS Fallback process may include the following steps:

S1. When the terminal device initiates a calling or called call, the terminal device resident in the NR cell (i.e. 5G cell) interacts with the 5G network (network, NW) based on SIP signaling to trigger the establishment of the multimedia subsystem (IP multimedia subsystem, IMS). )Voice conversation process.

S2 and 5G NW send a redirection message to the terminal device. The redirection message is used to instruct the terminal device to fall back to the 4G NW. The redirection message includes the network designated frequency point.

S3. The terminal device selects the 4G cell in the 4G NW according to the designated frequency point of the network.

S4. The terminal device executes the TAU program or the ATTACH process according to the network configuration to complete registration in the 4G cell, and the 4G network activates the voice bearer.

S5. Under 4G NW, the terminal device and the network continue to interact with each other through SIP to complete the final establishment of the call.

In the above process, when the called terminal equipment falls back to the 4G network (i.e., long term evolution (LTE) network), if the call establishment fails, the called terminal equipment can quickly return to the 5G network from the 4G network based on the Fast Return mechanism. . This is because terminal equipment always tries to stay on a higher-standard network to obtain better and more comprehensive services.

Specifically, after the called terminal equipment falls back to the 4G network, if it is determined that the call establishment fails, it can quickly return to 5G based on the FR mechanism. Specifically, the fast return (FR) timer can be started to switch back to the 5G network from the 4G network based on the following three methods.

1) Before the FR timer times out, if the network sends an RRC Release message (RRC connection release), and the RRC Release message carries NR frequency point information, the terminal device will search the network based on the NR frequency point information to return to the NR network (that is, re-station). Net to NR).

2) Before the FR timer times out, if the network issues an RRC Release message and the RRC Release message does not carry frequency information, the terminal device can return to the NR network based on the historical resident NR frequency information.

3) After the FR timer times out (after), if the terminal device does not receive the RRC Release message, the terminal device releases the local RRC connection (the terminal actively releases the RRC connection) and returns to the NR network based on the historical resident NR frequency point information. .

For the calling terminal device, when the call establishment fails, the calling terminal device usually automatically redials, or the user can manually redial to reinitiate the call process. Since the called terminal equipment has returned to 5G through the Fast Return mechanism (the FR timer usually does not exceed 5s), the called terminal equipment needs to perform the EPS Fallback process again, and the called terminal equipment may experience continuous EPS Fallback called failures. question.

In order to solve the above problem, embodiments of this application provide a method. When the called terminal equipment falls back to 4G during the EPS Fallback process, if the called call establishment fails, the called terminal equipment can be controlled to delay returning to the 5G network. In this way, when the calling terminal device redials, the called terminal device can directly establish a call on VOLTE, which greatly increases the possibility of successful call establishment (compared to EPS Fallback, VOLTE does not include falling back from 5G to 4G and re-establishing the call on 4G). The registration and other processes take a short time, and the VOLTE network has been commercially available for a long time and is relatively stable). As a result, it solves the problem of continuous EPS Fallback call failures encountered by users without basically affecting the user's registration in the 5G SA network, and can improve the user experience.

Compared with the existing technology, after the EPS Fallback fails, the called terminal device executes the Fast Return mechanism and quickly returns to 5G. As a result, the called terminal device needs to execute the EPS Fallback process again when the calling terminal device redials, and may encounter EPS continuously. Fallback execution failure problem. This application considers from the perspective of ensuring the success of the call, allowing the called terminal equipment to stay on LTE for a longer period of time, so that when the calling terminal equipment redials, the called terminal equipment can directly establish a call on VOLTE, improving the efficiency of the call. The called call pass rate. As a result, it solves the problem of continuous EPS Fallback call failures encountered by users without basically affecting the user's registration in the 5G SA network, and can improve the user experience.

Figure 2 shows a schematic diagram of a communication system to which the technical solution provided by the embodiment of the present application is applicable. The communication system may include a terminal device 100, a 5G NW 200, a 4G NW 300 and an IMS 400.

The terminal device 100 may be a calling terminal device (or called a calling-side terminal device) or a called-side terminal device (or called a called-side terminal device). The terminal device 100 may include a smartphone (such as a mobile phone equipped with an Android system or an iOS system), a tablet computer, a notebook computer, a handheld computer, a mobile Internet device (MID), a wearable device (such as a smart watch, a smart phone, etc.) ring, etc.) or other devices that can access the Internet. In the embodiment of this application, the terminal-side device may be a terminal sold independently, or may be a chip in the terminal. Among the technical solutions provided by the embodiments of the present application, the technical solution provided by the embodiments of the present application is described by taking the device for realizing the functions of the terminal being a terminal-side device as an example.

User information is stored in the terminal device 100 . The user information may include an international mobile subscriber identification number (IMSI). The IMSI may be stored in a subscriber identity module (SIM) card of the terminal device 100. The terminal device 100 can use the user information as an identity identifier to initiate or receive calls through various voice solutions.

The deployment method of 5G NW 200 is standalone (SA). Among them, the 5G NW 200 may include a 5G base station 201 and a 5G core network (5G core network, 5GC) 202. The 5G base station 201 is connected to the 5G core network 202, and the 5G core network 202 is connected to the IMS 400.

The 5G base station 201 may be a next generation base station (next generation NodeB, gNB). gNB can be connected to the terminal device 100 and communicate with the terminal device 100 using 5G NR access technology, that is, gNB and the terminal device 100 communicate through NR links.

The 5G core network 202 is used for switching, forwarding, connecting, and routing data. Network elements in the 5G core network 202 are functional virtual units, which may include but are not limited to: units used for access and mobility management functions (AMF), units used for session management functions (session management function (SMF), network elements for unified data management (unified data management, UDM), etc.

IMS 400 may mainly include call session control function entity (call session control function, CSCF) and home subscriber server (home subscriber server, HSS). CSCF is used to control signaling and authentication during multimedia call sessions, and cooperate with other network entities to control sessions, etc. HSS is used to manage user data.

The 4G NW 300 may include a 4G base station 301 and a 4G core network (evolved packet core, EPC) 302. The 4G base station 301 is connected to the 4G core network 302, and the 4G core network 302 is connected to the IMS 400.

The 4G base station 301 may be an evolved base station (evolved Node B, eNB).

The 4G core network 302 mainly includes the following network elements: mobility management entity (MME), serving gateway (SGW), packet data network gateway (PGW), home subscriber server (home subscriber server, HSS) and application server (application server, AS), etc. The main functions of MME include access control, mobility management, attachment and detachment, session management (such as bearer establishment, modification and release), etc. SGW is mainly used for routing and forwarding of data packets. The main functions of PGW include user-based packet filtering function, legal interception function, IP address allocation function, etc. HSS is used to store user subscription information, user subscription data, and mobile user location information.

It can be understood that the units shown in Figure 2 do not constitute a specific limitation on the communication system. The communication system may also include more or less units than shown in the figure, or combine some units, or split some units, or different The unit layout is not limited by this application.

As shown in FIG. 3 , it is a schematic structural diagram of a terminal device 100 provided by an embodiment of the present application. The terminal device 100 may be a first electronic device. As shown in Figure 3, the terminal device 100 may include a processor 410, an external memory interface 420, an internal memory 421, a universal serial bus (USB) interface 430, a charging management module 440, a power management module 441, and a battery 442 , Antenna 1, Antenna 2, mobile communication module 450, wireless communication module 460, audio module 470, speaker 470A, receiver 470B, microphone 470C, headphone interface 470D, sensor module 480, button 490, motor 491, indicator 492, camera 493 , display screen 494, and subscriber identification module (subscriber identification module, SIM) card interface 495, etc. Among them, the sensor module 480 may include a pressure sensor 480A, a gyro sensor 480B, an air pressure sensor 480C, a magnetic sensor 480D, an acceleration sensor 480E, a distance sensor 480F, a proximity light sensor 480G, a fingerprint sensor 480H, a temperature sensor 480J, a touch sensor 480K, and an environment. Light sensor 480L, bone conduction sensor 480M, etc.

The processor 410 may include one or more processing units. For example, the processor 410 may include an application processor (application processor, AP), a modem processor, a graphics processing unit (GPU), and an image signal processor. (image signal processor, ISP), controller, memory, video codec, digital signal processor (digital signal processor, DSP), baseband processor, and/or neural-network processing unit (NPU) wait. Among them, different processing units can be independent devices or integrated in one or more processors.

The controller may be the nerve center and command center of the terminal device 100 . The controller can generate operation control signals based on the instruction operation code and timing signals to complete the control of fetching and executing instructions.

The processor 410 may also be provided with a memory for storing instructions and data. In some embodiments, the memory in processor 410 is cache memory. This memory may hold instructions or data that have been recently used or recycled by processor 410 . If the processor 410 needs to use the instruction or data again, it can be called directly from the memory. Repeated access is avoided and the waiting time of the processor 410 is reduced, thus improving the efficiency of the system.

In some embodiments, processor 410 may include one or more interfaces. Interfaces may include integrated circuit (inter-integrated circuit, I2C) interface, integrated circuit built-in audio (inter-integrated circuit sound, I2S) interface, pulse code modulation (pulse code modulation, PCM) interface, universal asynchronous receiver and transmitter (universal asynchronous receiver/transmitter (UART) interface, mobile industry processor interface (MIPI), general-purpose input/output (GPIO) interface, subscriber identity module (SIM) interface, and /or universal serial bus (USB) interface, etc.

It can be understood that the interface connection relationships between the modules illustrated in this embodiment are only schematic illustrations and do not constitute a structural limitation on the terminal device 100 . In other embodiments, the terminal device 100 may also adopt different interface connection methods in the above embodiments, or a combination of multiple interface connection methods.

The charge management module 440 is used to receive charging input from the charger. Among them, the charger can be a wireless charger or a wired charger. In some wired charging embodiments, the charging management module 440 may receive charging input from the wired charger through the USB interface 430 . In some wireless charging embodiments, the charging management module 440 may receive wireless charging input through the wireless charging coil of the terminal device 100 . While charging the battery 442, the charging management module 440 can also provide power to the electronic device through the power management module 441.

The power management module 441 is used to connect the battery 442, the charging management module 440 and the processor 410. The power management module 441 receives input from the battery 442 and/or the charging management module 440, and supplies power to the processor 410, internal memory 421, external memory, display screen 494, camera 493, wireless communication module 460, etc. The power management module 441 can also be used to monitor battery capacity, battery cycle times, battery health status (leakage, impedance) and other parameters. In some other embodiments, the power management module 441 may also be provided in the processor 410. In other embodiments, the power management module 441 and the charging management module 440 can also be provided in the same device.

The wireless communication function of the terminal device 100 can be implemented through the antenna 1, the antenna 2, the mobile communication module 450, the wireless communication module 460, the modem processor and the baseband processor.

Antenna 1 and Antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in terminal device 100 may be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example: Antenna 1 can be reused as a diversity antenna for a wireless LAN. In other embodiments, antennas may be used in conjunction with tuning switches.

The mobile communication module 450 can provide wireless communication solutions including 2G/3G/4G/5G applied on the terminal device 100. The mobile communication module 450 may include at least one filter, switch, power amplifier, low noise amplifier (LNA), etc. The mobile communication module 450 can receive electromagnetic waves from the antenna 1, perform filtering, amplification and other processing on the received electromagnetic waves, and transmit them to the modem processor for demodulation. The mobile communication module 450 can also amplify the signal modulated by the modem processor and convert it into electromagnetic waves through the antenna 1 for radiation. In some embodiments, at least part of the functional modules of the mobile communication module 450 may be disposed in the processor 410 . In some embodiments, at least part of the functional modules of the mobile communication module 450 and at least part of the modules of the processor 410 may be provided in the same device.

A modem processor may include a modulator and a demodulator. Among them, the modulator is used to modulate the low-frequency baseband signal to be sent into a medium-high frequency signal. The demodulator is used to demodulate 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. After the low-frequency baseband signal is processed by the baseband processor, it is passed to the application processor. The application processor outputs sound signals through audio devices (not limited to speaker 470A, receiver 470B, etc.), or displays images or videos through display screen 494. In some embodiments, the modem processor may be a stand-alone device. In other embodiments, the modem processor may be independent of the processor 410 and may be provided in the same device as the mobile communication module 450 or other functional modules.

The wireless communication module 460 can provide applications on the terminal device 100 including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) network), Bluetooth (bluetooth, BT), and global navigation satellites. System (global navigation satellite system, GNSS), frequency modulation (frequency modulation, FM), near field communication technology (near field communication, NFC), infrared technology (infrared, IR) and other wireless communication solutions. The wireless communication module 460 may be one or more devices integrating at least one communication processing module. The wireless communication module 460 receives electromagnetic waves via the antenna 2 , frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 410 . The wireless communication module 460 can also receive the signal to be sent from the processor 410, frequency modulate it, amplify it, and convert it into electromagnetic waves through the antenna 2 for radiation.

In some embodiments, the antenna 1 of the terminal device 100 is coupled to the mobile communication module 450, and the antenna 2 is coupled to the wireless communication module 460, so that the terminal device 100 can communicate with the network and other devices through wireless communication technology. Wireless communication technologies can include global system for mobile communications (GSM), general packet radio service (GPRS), code division multiple access (CDMA), broadband code division Multiple access (wideband code division multiple access, WCDMA), time-division code division multiple access (TD-SCDMA), long term evolution (long term evolution, LTE), BT, GNSS, WLAN, NFC, FM , and/or IR technology, etc. GNSS can include global positioning system (GPS), global navigation satellite system (GLONASS), Beidou navigation satellite system (BDS), quasi-zenith satellite system (quasi-zenith) satellite system (QZSS) and/or satellite based augmentation systems (SBAS).

The terminal device 100 implements display functions through a GPU, a display screen 494, an application processor, and the like. The GPU is an image processing microprocessor and is connected to the display screen 494 and the application processor. GPUs are used to perform mathematical and geometric calculations for graphics rendering. Processor 410 may include one or more GPUs that execute program instructions to generate or alter display information.

Display 494 is used to display images, videos, etc.

Display 494 includes a display panel. The display panel can use a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active matrix organic light emitting diode or an active matrix organic light emitting diode (active-matrix organic light emitting diode). emitting diode (AMOLED), flexible light-emitting diode (FLED), Miniled, MicroLed, Micro-oLed, quantum dot light emitting diode (QLED), etc.

The terminal device 100 can implement the shooting function through the ISP, camera 493, video codec, GPU, display screen 494, application processor, etc.

The ISP is used to process the data fed back by the camera 493. For example, when taking a photo, the shutter is opened, the light is transmitted to the camera sensor through the lens, the light signal is converted into an electrical signal, and the camera sensor passes the electrical signal to the ISP for processing, and converts it into an image visible to the naked eye. ISP can also perform algorithm optimization on image noise, brightness, and skin color. ISP can also optimize the exposure, color temperature and other parameters of the shooting scene. In some embodiments, the ISP may be located in the camera 493.

Camera 493 is used to capture still images or video. The object passes through the lens to produce an optical image that is projected onto the photosensitive element. The photosensitive element can be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the optical signal into an electrical signal, and then passes the electrical signal to the ISP to convert it into a digital image signal. ISP outputs digital image signals to DSP for processing. DSP converts digital image signals into standard RGB, YUV and other format image signals. In some embodiments, the terminal device 100 may include 1 or N cameras 493, where N is a positive integer greater than 1.

Digital signal processors are used to process digital signals. In addition to digital image signals, they can also process other digital signals. For example, when the terminal device 100 selects a frequency point, the digital signal processor is used to perform Fourier transform on the frequency point energy.

Video codecs are used to compress or decompress digital video. The terminal device 100 may support one or more video codecs. In this way, the terminal device 100 can play or record videos in multiple encoding formats, such as moving picture experts group (MPEG) 1, MPEG2, MPEG3, MPEG4, etc.

NPU is a neural network (NN) computing processor. By drawing on the structure of biological neural networks, such as the transmission mode between neurons in the human brain, it can quickly process input information and can continuously learn by itself. The NPU can realize intelligent cognitive applications of the terminal device 100, such as image recognition, face recognition, speech recognition, text understanding, etc.

The external memory interface 420 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the terminal device 100. The external memory card communicates with the processor 410 through the external memory interface 420 to implement the data storage function. Such as saving music, videos, etc. files in external memory card. In the embodiment of this application, an external memory card (for example, Micro SD card) can be used to store all pictures in the system album. Micro SD cards are usually open to users, and users can freely delete and access pictures in the system album.

Internal memory 421 may be used to store computer executable program code, which includes instructions. The processor 410 executes instructions stored in the internal memory 421 to execute various functional applications and data processing of the terminal device 100 . For example, in this embodiment of the present application, the processor 410 may display corresponding display content on the display screen 494 in response to the user's second operation or first operation on the display screen 494 by executing instructions stored in the internal memory 421 . The internal memory 421 may include a program storage area and a data storage area. Among them, the stored program area can store an operating system, at least one application program required for a function (such as a sound playback function, an image playback function, etc.). The storage data area may store data created during use of the terminal device 100 (such as audio data, phone book, etc.). In addition, the internal memory 421 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, universal flash storage (UFS), read-only memory (read-only memory) memory, ROM), etc.

The terminal device 100 can implement audio functions through the audio module 470, the speaker 470A, the receiver 470B, the microphone 470C, the headphone interface 470D, and the application processor. Such as music playback, recording, etc.

The audio module 470 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. Audio module 470 may also be used to encode and decode audio signals. In some embodiments, the audio module 470 may be disposed in the processor 410, or some functional modules of the audio module 470 may be disposed in the processor 410. Speaker 470A, also known as "speaker", is used to convert audio electrical signals into sound signals. The terminal device 100 can listen to music through the speaker 470A, or listen to a hands-free call. Receiver 470B, also called "earpiece", is used to convert audio electrical signals into sound signals. When the terminal device 100 answers a call or a voice message, the voice can be heard by bringing the receiver 470B close to the human ear. Microphone 470C, also known as "microphone" and "microphone", is used to convert sound signals into electrical signals. The terminal device 100 may be provided with at least one microphone 470C. In some embodiments, the terminal device 100 may be provided with two microphones 470C, which in addition to collecting sound signals, may also implement a noise reduction function. In some embodiments, the terminal device 100 can also be equipped with three, four or more microphones 470C to collect sound signals, reduce noise, identify sound sources, and implement directional recording functions, etc.

Headphone interface 470D is used to connect wired headphones. The headphone interface 470D can be a USB interface 430, or a 3.5mm open mobile terminal platform (OMTP) standard interface, or a cellular telecommunications industry association of the USA (CTIA) standard interface.

The pressure sensor 480A is used to sense pressure signals and can convert the pressure signals into electrical signals. In some embodiments, pressure sensor 480A may be disposed on display screen 494. There are many types of pressure sensors 480A, such as resistive pressure sensors, inductive pressure sensors, capacitive pressure sensors, etc. A capacitive pressure sensor may include at least two parallel plates of conductive material. When a force is applied to pressure sensor 480A, the capacitance between the electrodes changes. The terminal device 100 determines the intensity of the pressure based on the change in capacitance. When a touch operation is performed on the display screen 494, the terminal device 100 detects the strength of the touch operation according to the pressure sensor 480A. The terminal device 100 may also calculate the touched position based on the detection signal of the pressure sensor 480A. In some embodiments, touch operations acting on the same touch location but with different touch operation intensities may correspond to different operation instructions. For example: when a touch operation with a touch operation intensity less than the first pressure threshold is applied to the short message application icon, an instruction to view the short message is executed. When a touch operation with a touch operation intensity greater than or equal to the first pressure threshold is applied to the short message application icon, an instruction to create a new short message is executed.

The gyro sensor 480B may be used to determine the motion posture of the terminal device 100 . In some embodiments, the angular velocity of the terminal device 100 around three axes (ie, x, y, and z axes) may be determined by the gyro sensor 480B. The gyro sensor 480B can be used for image stabilization. For example, when the shutter is pressed, the gyro sensor 480B detects the angle at which the terminal device 100 shakes, calculates the distance that the lens module needs to compensate based on the angle, and allows the lens to offset the shake of the terminal device 100 through reverse movement to achieve anti-shake. The gyro sensor 480B can also be used for navigation and somatosensory gaming scenarios.

Air pressure sensor 480C is used to measure air pressure. In some embodiments, the terminal device 100 calculates the altitude through the air pressure value measured by the air pressure sensor 480C to assist positioning and navigation.

Magnetic sensor 480D includes a Hall sensor. The terminal device 100 may use the magnetic sensor 480D to detect the opening and closing of the flip holster. In some embodiments, when the terminal device 100 is a flip machine, the terminal device 100 may detect the opening and closing of the flip according to the magnetic sensor 480D. Then, based on the detected opening and closing status of the leather case or the opening and closing status of the flip cover, features such as automatic unlocking of the flip cover are set.

The acceleration sensor 480E can detect the acceleration of the terminal device 100 in various directions (generally three axes). When the terminal device 100 is stationary, the magnitude and direction of gravity can be detected. It can also be used to identify the posture of electronic devices and be used in horizontal and vertical screen switching, pedometer and other applications.

Distance sensor 480F, used to measure distance. The terminal device 100 can measure distance through infrared or laser. In some embodiments, when shooting a scene, the terminal device 100 can use the distance sensor 480F to measure distance to achieve fast focusing.

Proximity light sensor 480G may include, for example, a light emitting diode (LED) and a light detector, such as a photodiode. The light emitting diode may be an infrared light emitting diode. The terminal device 100 emits infrared light through a light emitting diode. The terminal device 100 detects infrared reflected light from nearby objects using photodiodes. When sufficient reflected light is detected, it can be determined that there is an object near the terminal device 100 . When insufficient reflected light is detected, the terminal device 100 may determine that there is no object near the terminal device 100 . The terminal device 100 can use the proximity light sensor 480G to detect when the user holds the terminal device 100 close to the ear for talking, so as to automatically turn off the screen to save power. The proximity light sensor 480G can also be used in holster mode, and pocket mode automatically unlocks and locks the screen.

The ambient light sensor 480L is used to sense ambient light brightness. The terminal device 100 can adaptively adjust the brightness of the display screen 494 according to the perceived ambient light brightness. The ambient light sensor 480L can also be used to automatically adjust white balance when taking photos. The ambient light sensor 480L can also cooperate with the proximity light sensor 480G to detect whether the terminal device 100 is in the pocket to prevent accidental touching.

Fingerprint sensor 480H is used to collect fingerprints. The terminal device 100 can use the collected fingerprint characteristics to realize fingerprint unlocking, access application lock, fingerprint photography, fingerprint answering incoming calls, etc.

Temperature sensor 480J is used to detect temperature. In some embodiments, the terminal device 100 uses the temperature detected by the temperature sensor 480J to execute the temperature processing policy. For example, when the temperature reported by the temperature sensor 480J exceeds a threshold, the terminal device 100 reduces the performance of a processor located near the temperature sensor 480J in order to reduce power consumption and implement thermal protection. In other embodiments, when the temperature is lower than another threshold, the terminal device 100 heats the battery 442 to prevent the low temperature from causing the terminal device 100 to shut down abnormally. In some other embodiments, when the temperature is lower than another threshold, the terminal device 100 performs boosting on the output voltage of the battery 442 to avoid abnormal shutdown caused by low temperature.

Touch sensor 480K, also known as "touch panel". The touch sensor 480K can be disposed on the display screen 494. The touch sensor 480K and the display screen 494 form a touch screen, which is also called a "touch screen". Touch sensor 480K is used to detect a touch operation on or near it. The touch sensor can pass the detected touch operation to the application processor to determine the touch event type. Visual output related to the touch operation may be provided through display screen 494. In other embodiments, the touch sensor 480K may also be disposed on the surface of the terminal device 100 in a position different from that of the display screen 494 .

Bone conduction sensor 480M can acquire vibration signals. In some embodiments, the bone conduction sensor 480M can acquire the vibration signal of the vibrating bone mass of the human body's vocal part. The bone conduction sensor 480M can also contact the human body's pulse and receive blood pressure beating signals. In some embodiments, the bone conduction sensor 480M can also be provided in the earphone and combined into a bone conduction earphone. The audio module 470 can analyze the voice signal based on the vibration signal of the vibrating bone piece of the vocal part acquired by the bone conduction sensor 480M, and implement the voice function. The application processor can analyze the heart rate information based on the blood pressure beat signal obtained by the bone conduction sensor 480M to implement the heart rate detection function.

The buttons 490 include a power button, a volume button, etc. Key 490 may be a mechanical key. It can also be a touch button. The terminal device 100 may receive key input and generate key signal input related to user settings and function control of the terminal device 100 .

Motor 491 can produce vibration prompts. Motor 491 can be used for vibration prompts for incoming calls and can also be used for touch vibration feedback. For example, touch operations for different applications (such as taking pictures, audio playback, etc.) can correspond to different vibration feedback effects. Acting on touch operations in different areas of the display screen 494, the motor 491 can also correspond to different vibration feedback effects. Different application scenarios (such as time reminders, receiving information, alarm clocks, games, etc.) can also correspond to different vibration feedback effects. The touch vibration feedback effect can also be customized.

The indicator 492 may be an indicator light, which may be used to indicate charging status, power changes, or may be used to indicate messages, missed calls, notifications, etc.

The SIM card interface 495 is used to connect a SIM card. The SIM card can be connected to or separated from the terminal device 100 by inserting it into the SIM card interface 495 or pulling it out from the SIM card interface 495 . The terminal device 100 can support 1 or N SIM card interfaces, where N is a positive integer greater than 1. SIM card interface 495 can support Nano SIM card, Micro SIM card, SIM card, etc. The same SIM card interface 495 can insert multiple cards at the same time. Multiple cards can be of the same type or different types. The SIM card interface 495 is also compatible with different types of SIM cards. The SIM card interface 495 is also compatible with external memory cards. The terminal device 100 interacts with the network through the SIM card to implement functions such as calls and data communications. In some embodiments, the terminal device 100 adopts eSIM, that is, an embedded SIM card. The eSIM card can be embedded in the terminal device 100 and cannot be separated from the terminal device 100 .

The methods in the following embodiments can all be implemented in the terminal device 100 with the above hardware structure.

It can be understood that the structure illustrated in this embodiment does not constitute a specific limitation on the terminal device 100. In other embodiments, the terminal device 100 may include more or less components than shown in the figures, or some components may be combined, or some components may be separated, or may be arranged differently. The components illustrated may be implemented in hardware, software, or a combination of software and hardware. For example, the terminal device 100 may also include auxiliary devices such as a mouse, a keyboard, and a drawing pad to perform the process of creating, transmitting, receiving, and customizing target expressions.

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Among them, in the description of this application, unless otherwise specified, "at least one" refers to one or more, and "plurality" refers to two or more than two. In addition, in order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as “first” and “second” are used to distinguish identical or similar items with basically the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the number and execution order, and words such as "first" and "second" do not limit the number and execution order.

For ease of understanding, the voice calling method provided by the embodiment of the present application will be introduced in detail below with reference to the accompanying drawings.

As shown in Figure 4, this embodiment of the present application provides a voice call method, including:

401. In response to user operation, the calling terminal device (first terminal device) sends a call request message.

For example, the call request message may be an INVITE sip message. The call request message can reach the NR network where the called terminal equipment is registered via the calling side network (the network where the calling terminal equipment is registered).

Among them, the calling side network can include 5G NR network, 4G LTE network, 3G/2G network, etc. That is, the calling terminal device can be registered (or parked) in the 5G NR network, 4G LTE network, 3G/2G network, etc. This application does not limit it.

In response to the user's operation of dialing the number, the calling terminal device sends a call request message. For example, the user can open the phone application or address book application of the calling terminal device (for example, a mobile phone), and enter or select the called number. As shown in (a) of Figure 5, the calling terminal device can display the dialing interface 501, and in response to the user's operation of clicking the dial button 502 on the interface 501, the calling terminal device sends a call request message. At the same time, as shown in (b) of Figure 5, the calling terminal device can display an interface 503, and the interface 503 can include a text prompt 504 to prompt the user that the called user is being called. Of course, the user can also initiate a call to the called user through other methods (for example, through the address book), which is not limited in this embodiment of the present application.

402. The NR network on the called side sends a paging message to the called terminal device (second terminal device).

403. After receiving the paging message, the called terminal device initiates the NR RRC establishment process.

It should be noted that step 403 is not a necessary process. The RRC establishment process is only required when the called mobile phone is in the idle state.

404. The called terminal device performs SIP signaling interaction with the NR network on the called side.

Specifically, the NR network on the called side may send an invitation (INVITE) message to the called terminal device. After receiving the INVITE message, the called terminal device can reply to SIP messages such as 100trying message and session progress message (183Session Progress message). Among them, the 100trying message is used to indicate that the INVITE message has been received. The 183 message is used to prompt the progress of session establishment and session description protocol (session description protocol, SDP) negotiation.

405. The NR network on the called side sends an RRC connection release message to the called terminal device, instructing the called terminal device to fall back to 4G.

Among them, the RRC connection release message carries target frequency point information, and the target frequency point corresponds to the LTE cell.

If the NR network on the called side supports the N26 interface (that is, the AMF supports the N26 interface), the 5G radio access network (NG-RAN) can perform EPS fallback through handover or redirection and use IMS voice services. If AMF does not support the N26 interface, NG-RAN can only redirect EPS fallback and use IMS voice services. Among them, N26 is the interface between the 4G core network and the 5G core network and is used for the interoperability of 4G and 5G.

406. The called terminal equipment selects an LTE cell to camp on based on the frequency point designated by the NR network on the called side.

That is, the called UE can select an LTE cell to camp on based on the target frequency point.

407. The called terminal device initiates a TAU/ATTACH request.

After the called terminal device is connected to the 4G base station, it can initiate a TAU/ATTACH request to the 4G core network through the 4G base station.

When the N26 interface is supported between the 4G core network and the 5G core network, the called terminal device initiates a TAU request (request), otherwise it initiates an attach request (ATTACH request). Among them, the ATTACH request includes tracking area identity (TAI) and evolved universal terrestrial radio access network cell global identifier (E-UTRAN (evolved universal terrestrial radio access network) Cell Global Identifier, ECGI) and other information . TAU request includes information such as TAI, ECGI and voice domin preference.

408. The called terminal device completes the process of establishing the RRC connection on LTE.

The ATTCH/TAU request at the non-access stratum (NAS) layer can trigger the called terminal device to establish an RRC connection at the access stratum (AS) layer. Specifically, the called terminal device can send an RRC connection request message to the network device, and the network device replies with an RRC connection setup message to the called terminal device, and then the called terminal device sends an RRC connection complete message to complete the RRC connection establishment.

409. The called terminal device completes the LTE registration process.

The called terminal device can receive an ATTACH accept (ATTACH accept) or tracking area accept (TAU accept) message from the LTE network on the called side. The called terminal device replies an ATTACH complete or TAU complete message to the LTE network on the called side to complete LTE. registration process.

Among them, ATTACH accept includes the tracking area list (TAL). The TAL includes multiple TAs. When the called terminal device moves among multiple TAs indicated by the TAL, it does not need to perform TA updates to reduce frequent interactions with the network.

410. The LTE network on the called side activates the voice bearer.

After the called terminal device completes registration in LTE, the network side can trigger the establishment of a voice bearer with a QoS (quality of service) class identifier (QCI) of 1, so that subsequent calls can be made through this voice bearer.

411. The called terminal device completes the establishment of the subsequent call process on 4G LTE.

Specifically, the called terminal interacts with the LTE network on the called side such as provisional response acknowledgment (PRACK)/status update (update) and other SIP messages. The specific process may refer to the existing technology and will not be described in detail here. Afterwards, the called terminal device sends a 180Ringing message to the calling terminal device through the LTE network on the called side. The called terminal device prompts incoming call information on the UI, and the user can choose to answer the call to complete the call establishment. At this point, the call is completely established.

It should be noted that after step 405, the called terminal device falls back to 4G. If an abnormality occurs in any step or between steps 406, 407, 408, 409, 410 or 411 (for example, the signal quality of the LTE cell corresponding to the designated frequency point (target frequency point) of the network is poor and there is a neighbor with better signal quality. area (the neighboring cell does not belong to the LTE cell corresponding to the target frequency point), slow TAU causes resource reservation timeout, failure to send SIP messages, or the called terminal device receives error code 503 indicating that the call was abnormally released, etc.) , after the called terminal equipment falls back to 4G, it cannot complete the establishment of the call process with the calling terminal equipment.

In order to solve the above problem, the called terminal device can perform the following steps:

412. The called terminal equipment starts the slow return (Slow Return) timer (i.e., the first timer). During the start of the Slow Return timer, the UE does not return to the 5G network through reselection or handover.

Preferably, if the called terminal equipment fails to establish a call before sending a ringing message to the network, the called terminal equipment can start the Slow Return timer (first timer). The name of the Slow Return timer is just an example and is not limited by this application. During the start of the Slow Return timer, the UE does not return to the 5G network through reselection or handover, and remains resident on the 4G network, waiting for the network to call again.

In order to remain resident on the 4G network, during the start of the Slow Return timer, the called terminal device can suppress 5G SA (e.g., suppress NR measurements; and/or disable 5G SA capabilities), or limit reselection and handover to 5G .

Optionally, before the called terminal equipment starts the Slow Return timer, it can be determined whether the called terminal equipment meets the preset conditions. The preset conditions include: the called terminal device does not open the preset application, the called terminal device does not open the game mode or performance mode, and/or the called terminal device is in a screen-off state. Among them, the preset application programs may include programs with high data transmission rate requirements. For example, game applications, live broadcast applications, etc.

It is understandable that when the called terminal device meets the preset conditions, that is, when the preset application is not opened, the game mode or performance mode is not turned on, and/or the screen is off, the requirements for network quality and data transmission rate are low. , can reside on a lower standard network (for example, 4G network) to provide services to users. At this time, turning on the Slow Return timer will not affect the normal operation of the called terminal equipment, and can improve the call completion rate of the called terminal equipment. When the called terminal device does not meet the preset conditions, for example, the called terminal device opens a preset application, turns on game mode or performance mode, or is in a bright screen state, it has higher requirements for data transmission rate and network quality. , It is necessary to reside on a high-standard network (for example, 5G network) as soon as possible to provide users with smoother services. At this time, you can disable the Slow Return timer to avoid affecting the normal operation of the called terminal device.

It should be added that the Slow Return timer is started when the called terminal device determines that the call establishment failed after falling back to LTE (4G) during the EPS Fallback process. That is, the Slow Return timer is started only when the EPS Fallback process fails abnormally. . If the EPS Fallback call process is successfully established, the existing Fast Return mechanism can be used after the call ends.

Among them, the length of the Slow Return timer can be determined based on the time required for the calling terminal device to redial, for example, the value can be 45 seconds. There are no specific limitations in this application.

413. The calling terminal device initiates a redial operation to the called device.

The calling terminal device can automatically initiate redialing, or the user can initiate redialing manually.

For example, as shown in (a) of FIG. 6 , when the call establishment fails for the first time, the calling terminal device may display the interface 505 , and the interface 505 may include a single redial button 506 . In response to the user clicking single redial button 506, the calling terminal device may enter single redial. If the peer is still not connected, as shown in (b) of Figure 6, the calling terminal device may display an interface 507, which may include an infinite redial button 508, in response to the user clicking the infinite redial button 508. , the calling terminal device can enter automatic replay. The calling terminal device can repeatedly dial the entered number before the call is connected.

Alternatively, the user can pre-set in the call application of the calling terminal device to allow automatic redialing or the terminal device supports automatic redialing in specific scenarios. In this way, when the first call fails to establish a call, the mobile phone can automatically enter automatic redialing. There is no need for users to perform manual redial operations.

414. If the called terminal equipment receives an incoming call from the calling terminal equipment again before the timer times out, it will directly establish a connection with the calling terminal equipment through VOLTE.

As shown in Figure 7, when the EPS Fallback process ends, the called terminal device determines whether the EPS Fallback process failed abnormally. If it is determined that the EPS Fallback process fails abnormally, you can start the Slow Return timer. If it is determined that the EPS Fallback process did not fail abnormally (that is, it ended normally), after the call ends, it can quickly return to 5G based on the FR mechanism. Among them, the duration of the Slow Return timer (for example, 45s) is greater than the Fast Return timer (for example, 5s). After the called terminal device starts the Slow Return timer, it determines whether a new incoming call is received before the Slow Return timer expires. If the calling terminal device reinitiates the call, the called terminal device can receive the paging message or INVITE message on 4G again before the timer expires. At this time, it can be considered that the called terminal device received the paging message or INVITE message before the Slow Return timer expires. New call. If a new incoming call is received before the Slow Return timer expires, the Slow Return timer can be terminated and a call connection is established with the calling terminal device based on VOLTE.

If the calling terminal device does not reinitiate the call, or if the calling terminal device reinitiates the call, but the called terminal device does not receive the paging message or INVITE message before the Slow Return timer times out, it can be considered that the called terminal device No new calls were received before the timer expired. At this time, when the Slow Return timer times out, the called terminal device can quickly return to the 5G network. For example, the terminal device can return to the NR network based on the historical resident NR frequency point information.

Based on the method provided by the embodiment of this application, when it is determined that the EPS Fallback call establishment fails, the called terminal device can start the Slow Return timer. Before the Slow Return timer expires, the called terminal device will not return to the 5G network through reselection or handover. That is, the called terminal device can be allowed to stay on 4G LTE for a longer period of time. In this way, when the calling terminal equipment redials, the called terminal equipment uses the VOLTE method to establish a call with the calling terminal equipment, which greatly increases the possibility of successful call establishment. This solves the problem of continuous EPS Fallback call failures encountered by some users without basically affecting the user's resident 5G SA network, which can improve user experience.

The following is a more detailed example of how this application solves the problem of continuous EPS Fallback failures. For example, when the LTE cell corresponding to the network-specified frequency point (for example, an LTE weak-signal macro cell) has poor signal quality and there is a neighboring cell with better signal quality (for example, an LTE strong-signal indoor sub-cell), the terminal device determines the signal based on the network-specified frequency. When the frequency point is stationed in the cell network, it will camp in the LTE weak signal macro cell. Although the subsequent network can prompt the terminal device to switch to the LTE strong signal indoor cell based on reconfiguration, EPS Fallback failure often occurs before the cell handover is completed. If the terminal device quickly returns to the 5G network based on the FR mechanism, when the EPS Fallback process is initiated again, it will camp on the weak signal macro cell again based on the network designated frequency point, which may cause the EPS Fallback to fail again. When the solution of the embodiment of this application is adopted, after the first EPS Fallback fails, the UE can stay in the LTE network for a longer period of time. At this time, the UE has camped in the LTE strong signal indoor cell based on handover or reselection. When the called terminal device receives an incoming call from the calling terminal device again, it can directly establish a VOLTE call on the strong-signal indoor sub-cell without initiating the EPS Fallback process, thereby avoiding the problem of continuous EPS Fallback failures.

For another example, in the early days of SA network deployment, some networks had serious compatibility issues. When the UE falls back to the LTE network through EPS Fallback, the TAU process takes a long time and the TAU ACCEPT message reply is slow. This will cause the resource reservation to time out and eventually cause the EPS Fallback to fail. After EPS Fallback fails, if the terminal device quickly returns to the 5G network based on the FR mechanism, when EPS Fallback is initiated again, the problem of EPS Fallback failure due to slow TAU may be encountered again. After adopting the solution provided by the embodiment of this application, the UE can stay in the LTE network for a longer period of time. In this way, when the calling terminal device receives a call again, the called terminal device can receive the incoming call directly on LTE without the need to perform TAU, that is, there is no need to initiate the EPS Fallback process again, thereby avoiding the problem of continuous EPS Fallback failures.

An embodiment of the present application also provides a chip system. As shown in FIG. 8 , the chip system includes at least one processor 801 and at least one interface circuit 802 . The processor 801 and the interface circuit 802 may be interconnected by wires. For example, interface circuitry 802 may be used to receive signals from other devices (eg, memory of an electronic device). As another example, interface circuit 802 may be used to send signals to other devices (eg, processor 801).

For example, the interface circuit 802 may read instructions stored in a memory in the electronic device and send the instructions to the processor 801 . When the instructions are executed by the processor 801, the terminal device (the terminal device 100 shown in FIG. 3) can be caused to perform various steps in the above embodiments.

Of course, the chip system may also include other discrete devices, which are not specifically limited in the embodiments of this application.

Embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium includes computer instructions. When the computer instructions are run on an electronic device (the terminal device 100 shown in Figure 3), the terminal device causes the terminal device to 100 executes each function or step performed by the calling terminal device or the called terminal device in the above method embodiment.

An embodiment of the present application also provides a computer program product. When the computer program product is run on a computer, it causes the computer to perform various functions or steps performed by the electronic device in the above method embodiment.

The embodiment of the present application also provides a voice calling device. The device can be divided into different logical units or modules according to functions. Each unit or module performs different functions, so that the device performs the electronic equipment in the above method embodiment. Each function or step performed.

Through the above description of the embodiments, those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above functional modules is used as an example. In actual applications, the above functions can be allocated as needed. It is completed by different functional modules, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. For the specific working processes of the systems, devices and units described above, reference can be made to the corresponding processes in the foregoing method embodiments, which will not be described again here.

In the several embodiments provided in this embodiment, it should be understood that the disclosed system, device and method can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, for example, multiple units or components may be The combination can either be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the coupling or direct coupling or communication connection between each other shown or discussed may be through some interfaces, and the indirect coupling or communication connection of the devices or units may be in electrical, mechanical or other forms.

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

In addition, each functional unit in each embodiment of this embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware or software functional units.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this embodiment is essentially or contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , including several instructions to cause a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the method described in each embodiment. The aforementioned storage media include: flash memory, mobile hard disk, read-only memory, random access memory, magnetic disk or optical disk and other media that can store program codes.

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be covered by the protection scope of the present application. . Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A voice call method, characterized in that it is applied to a communication system including a first terminal device and a second terminal device, and the second terminal device resides in a fifth-generation mobile communication system independent networking 5G SA network;

The first terminal device initiates a call to the second terminal device;

The second terminal device initiates the Evolved Packet System Fallback voice bearer EPS Fallback to establish a voice call with the first terminal device;

After the second terminal equipment falls back to the Long Term Evolution LTE network, it is determined that EPS Fallback fails;

The second terminal device starts a first timer, and during the startup of the first timer, the second terminal device resides on the LTE network.
The method of claim 1, further comprising:

Before the first timer times out, the second terminal device establishes a VOLTE voice call with the first terminal device.
The method according to claim 2, characterized in that:

After the VOLTE voice call established between the second terminal device and the first terminal device ends, the second terminal device re-camps to the 5G SA network.
The method according to any one of claims 1 to 3, characterized in that starting the first timer by the second terminal device includes:

If the second terminal device meets the preset condition, start the first timer;

Wherein, the preset conditions include: the second terminal device does not open the preset application program, the second terminal device does not open the game mode, and/or the second terminal device is in a screen-off state.
The method according to any one of claims 1 to 4, characterized in that the reasons for the EPS Fallback failure include at least one of the following:

The signal quality of the LTE cell corresponding to the designated frequency point of the network is lower than the preset threshold and the signal quality of the neighboring cells of the LTE cell is higher than the preset threshold. The tracking area update TAU duration is longer than the preset duration, resulting in resource reservation failure and session initialization. The protocol SIP message fails to be sent, and the second terminal device receives error code 503 indicating that the call was abnormally released.
The method according to any one of claims 1 to 5, characterized in that,

During the startup of the first timer, the second terminal device suppresses 5G SA or restricts reselection and handover to 5G.
The method according to any one of claims 1 to 6, characterized in that the method further includes:

If the second terminal device determines that EPS Fallback is successful, the second terminal device establishes a voice call with the first terminal device;

After the call between the second terminal device and the first terminal device ends, the second terminal device re-camps on the 5G SA network.
The method according to claim 7, characterized in that re-camping the second terminal device to the 5G SA network includes:

The second terminal device starts a second timer, and before the second timer times out, receives a first radio resource control release RRC release message issued by the network device. The first RRC release message carries a new wireless NR frequency. point information, the second terminal device searches the network based on the NR frequency point information and sets up on the 5G SA network; or

Before the second timer times out, receive the second RRC release message issued by the network device. The second RRC release message does not carry NR frequency point information. The second terminal device is based on the historical resident NR frequency point. information back to the 5G SA network; or

After the second timer times out, if the first RRC release message or the second RRC release message is not received, the second terminal device returns to the 5G SA network based on the historical resident NR frequency point information.
A voice call method, characterized in that it is applied to a communication system including a first terminal device and a second terminal device, and the second terminal device resides in a fifth-generation mobile communication system independent networking 5G SA network;

The second terminal device receives call signaling corresponding to the call initiated by the first terminal device;

The second terminal device initiates the Evolved Packet System Fallback voice bearer EPS Fallback to establish a voice call with the first terminal device;

After the second terminal equipment falls back to the Long Term Evolution LTE network, it is determined that EPS Fallback fails;

The second terminal device starts a first timer, and during the startup of the first timer, the second terminal device resides on the LTE network.
The method of claim 9, further comprising:

Before the first timer times out, the second terminal device establishes a VOLTE voice call with the first terminal device.
The method according to claim 10, characterized in that:

After the VOLTE voice call established between the second terminal device and the first terminal device ends, the second terminal device re-camps to the 5G SA network.
The method according to any one of claims 9 to 11, wherein starting the first timer by the second terminal device includes:

If the second terminal device meets the preset condition, start the first timer;

Wherein, the preset conditions include: the second terminal device does not open the preset application program, the second terminal device does not open the game mode, and/or the second terminal device is in a screen-off state.
The method according to any one of claims 9 to 12, characterized in that the reasons for the EPS Fallback failure include at least one of the following:

The signal quality of the LTE cell corresponding to the designated frequency point of the network is lower than the preset threshold and the signal quality of the neighboring cells of the LTE cell is higher than the preset threshold. The tracking area update TAU duration is longer than the preset duration, resulting in resource reservation failure and session initialization. The protocol SIP message fails to be sent, and the second terminal device receives error code 503 indicating that the call was abnormally released.
The method according to any one of claims 9 to 13, characterized in that,

During the activation period of the first timer, the second terminal device suppresses 5G SA, or restricts reselection and handover to 5G.
The method according to any one of claims 9 to 14, characterized in that the method further includes:

If the second terminal device determines that EPS Fallback is successful, the second terminal device establishes a voice call with the first terminal device;

After the call between the second terminal device and the first terminal device ends, the second terminal device re-camps to the 5G SA network.
The method according to claim 15, characterized in that re-camping the second terminal device to the 5G SA network includes:

The second terminal device starts a second timer, and before the second timer times out, receives a first radio resource control release RRC release message issued by the network device. The first RRC release message carries a new wireless NR frequency. point information, the second terminal device searches the network based on the NR frequency point information and sets up on the 5G SA network; or

Before the second timer times out, receive the second RRC release message issued by the network device. The second RRC release message does not carry NR frequency point information. The second terminal device is based on the historical resident NR frequency point. information back to the 5G SA network; or

After the second timer times out, if the first RRC release message or the second RRC release message is not received, the second terminal device returns to the 5G SA network based on the historical resident NR frequency point information.
A computer-readable storage medium, characterized by including computer instructions;

When the computer instructions are executed on the second terminal device, the second terminal device is caused to perform the method according to any one of claims 9-16.
A second terminal device, characterized in that it includes a processor, the processor is coupled to a memory, the memory stores program instructions, and when the program instructions stored in the memory are executed by the processor, the first The two terminal devices implement the method described in any one of claims 9-16.
A chip system, characterized in that the chip system includes one or more interface circuits and one or more processors; the interface circuit and the processor are interconnected through lines;

The chip system is applied to a second terminal device including a communication module and a memory; the interface circuit is used to receive a signal from the memory and send the signal to the processor, where the signal includes information stored in the memory. computer instructions; when the processor executes the computer instructions, the second terminal device performs the method according to any one of claims 9-16.
A voice call system, characterized in that it includes a first terminal device and a second terminal device, and the first terminal device and the second terminal device are used to perform the method described in any one of claims 1-8. method.