CN113068235A

CN113068235A - Circuit domain fallback method and device, computer readable storage medium and electronic equipment

Info

Publication number: CN113068235A
Application number: CN202110282730.5A
Authority: CN
Inventors: 刘宇
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2021-03-16
Filing date: 2021-03-16
Publication date: 2021-07-02
Anticipated expiration: 2041-03-16
Also published as: CN113068235B

Abstract

The disclosure relates to the technical field of communication, and provides a circuit switched fallback method and device, a storage medium and electronic equipment, wherein the method is applied to terminal equipment and comprises the following steps: receiving a first indication message sent by network equipment, wherein the first indication message comprises information of a fallback cell; when the fallback cell is determined to be a cell corresponding to a non-circuit domain network according to the information of the fallback cell, ignoring the first indication message; and selecting a cell corresponding to the circuit domain network as a target fallback cell, and trying to reside in the target fallback cell to carry out voice call. The method and the device can avoid the terminal equipment from switching to the cell corresponding to the non-circuit domain network according to the first indication information of the network equipment, and improve the success rate of circuit domain fallback.

Description

Circuit domain fallback method and device, computer readable storage medium and electronic equipment

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a circuit domain fallback method, a circuit domain fallback device, a computer-readable storage medium, and an electronic device.

Background

In the prior art, voice call can be realized through a circuit domain fallback technology in a range of overlapping coverage between an LTE network and a second generation mobile communication technology (2rd-generation, abbreviated as 2G) or a third generation mobile communication technology (3rd-generation, abbreviated as 3G) network.

Circuit Switched Fall Back (CSFB), which is a standard long term evolution LTE solution for the third Generation Partnership Project (3 GPP) protocol, that is, when a user has a voice call request, the terminal falls Back to the 2G or 3G network to perform a voice call. In the circuit switched fallback process, the LTE network issues a first indication message with a target 2G or 3G cell through a radio resource control protocol, and after receiving the first indication message, the terminal quickly registers to the 2G or 3G cell to perform voice service, so that voice call is completed.

Currently, with the application of a fifth generation mobile communication technology (5th-generation, abbreviated as 5G) network, there is a fallback information with a target 5G cell issued by an LTE network in the circuit domain fallback process. If the terminal registers from the LTE network to the 5G cell according to the protocol, the call waiting time is too long or the call fails.

Disclosure of Invention

An object of the present disclosure is to provide a circuit domain fallback method, a circuit domain fallback device, a computer readable storage medium, and an electronic device, so as to solve the problem of too long call waiting time or call failure at least to a certain extent.

According to a first aspect of the present disclosure, there is provided a circuit domain fallback method, which is applied to a terminal device, and includes: receiving a first indication message sent by network equipment, wherein the first indication message comprises information of a fallback cell; when the fallback cell is determined to be a cell corresponding to a non-circuit domain network according to the information of the fallback cell, ignoring the first indication message; and selecting a cell corresponding to the circuit domain network as a target fallback cell, and trying to reside in the target fallback cell to carry out voice call.

According to a second aspect of the present disclosure, there is provided a circuit domain fall back device, the device comprising: a message receiving module, configured to receive a first indication message sent by a network device, where the first indication message includes information of a fallback cell; a message ignoring module, configured to ignore the first indication message when determining, according to the information of the fallback cell, that the fallback cell is a cell corresponding to a non-circuit domain network; and the selective residing module is used for selecting the cell corresponding to the circuit domain network as a target fallback cell and trying to reside in the target fallback cell to carry out voice communication.

According to a third aspect of the present disclosure, there is provided a computer readable medium, on which a computer program is stored, which when executed by a processor, implements the circuit domain fallback method as described in the above embodiments.

According to a fourth aspect of the present disclosure, there is provided an electronic device comprising: one or more processors; a storage device for storing one or more programs which, when executed by the one or more processors, cause the one or more processors to implement the circuit domain fallback method as described in the above embodiments.

The circuit switched fallback method receives a first indication message sent by network equipment, wherein the first indication message comprises information of a fallback cell; when the fallback cell is determined to be a cell corresponding to the non-circuit domain network according to the information of the fallback cell, ignoring the first indication message; and selecting a cell corresponding to the circuit domain network as a target fallback cell, and trying to reside in the target fallback cell to carry out voice call. In the circuit switched fallback method disclosed by the disclosure, when the fallback cell in the first indication message is a cell corresponding to the non-circuit switched network, the terminal device can ignore the first indication message, actively select a cell corresponding to the circuit switched network, and determine a target fallback cell. The method and the device avoid the circuit domain fallback failure caused by the fact that the terminal device is switched to the cell corresponding to the non-circuit domain network according to the first indication message of the network device, thereby reducing the waiting time for accessing the voice call, improving the success rate of establishing the voice call connection and improving the user experience.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure. It is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without the exercise of inventive faculty.

Fig. 1 schematically shows a structural schematic diagram of a networking scenario according to an embodiment of the present disclosure;

fig. 2 schematically shows a structural schematic diagram of an electronic device according to an embodiment of the present disclosure;

FIG. 3 schematically illustrates a flow diagram of a circuit domain looping method according to an embodiment of the present disclosure;

fig. 4 schematically illustrates a flowchart of a method of determining a target fallback cell according to an embodiment of the present disclosure;

fig. 5 schematically illustrates a flowchart of a method of determining candidate fallback cells according to an embodiment of the present disclosure;

fig. 6 schematically illustrates a flowchart of a method of attempting to camp on a target fallback cell according to an embodiment of the present disclosure;

FIG. 7 is a flow diagram schematically illustrating a circuit switched fallback method according to a specific embodiment of the present disclosure;

fig. 8 schematically illustrates a block diagram of a circuit domain fall back apparatus according to an embodiment of the present disclosure.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the subject matter of the present disclosure can be practiced without one or more of the specific details, or with other methods, components, devices, steps, and so forth. In other instances, well-known methods, devices, implementations, or operations have not been shown or described in detail to avoid obscuring aspects of the disclosure.

The block diagrams shown in the figures are functional entities only and do not necessarily correspond to physically separate entities. I.e. these functional entities may be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor means and/or microcontroller means.

The flow charts shown in the drawings are merely illustrative and do not necessarily include all of the contents and operations/steps, nor do they necessarily have to be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the actual execution sequence may be changed according to the actual situation.

In the related art in the field, according to the specification of 3GPP protocol 36.331, in the CSFB process, after receiving an RRC connection release message issued by an LTE network through Radio Resource Control (RRC). If the RRC connection release message includes a redirection message (RedirectedCarrierInfo), the terminal needs to select and camp according to the cell information included in the redirection message. In addition, the LTE network may also issue a handover message (RRC Connection Reconfiguration) including cell information, so that the terminal selects and camps on the cell information included in the handover message.

With the popularization of 5G networks and terminal devices supporting 5G network technology, more and more areas are overlappingly covered by LTE networks, 5G networks and 2G networks, or by LTE networks, 5G networks and 3G networks. Moreover, more and more terminal devices support an LTE network, a 5G network, and a 2G network, or support an LTE network, a 5G network, and a 3G network.

In the above background, when the terminal device enters the CSFB procedure, since the network device corresponding to the LTE network may have network abnormality or the network architecture is not reasonable, the LTE network may send the cell information with the 5G network to the terminal device as a redirection message or a handover message. When receiving the redirection message or the handover message, the terminal device attempts to camp on and access the 5G network according to the protocol specification, which may cause a CSFB procedure failure or increase a CSFB call delay, thereby causing a voice call to have an excessively long waiting time or a call failure.

Based on the problems in the related art, the embodiments of the present disclosure first provide a circuit domain fallback method, where the circuit domain fallback method is applied to a networking scenario, and the method is applied when a terminal device issues a voice call in an LTE network, and at this time, the terminal device does not start the voice call. Referring to fig. 1, in the networking scenario, the terminal device is in an overlapping coverage range of a 2G/3G network, an LTE network, and a 5G network, and the terminal device is currently connected to the LTE network, where the base station a is a base station to which the 2G/3G network belongs, the base station B is a base station to which the LTE network belongs, and the base station C is a base station to which the 5G network belongs. The base station and the terminal equipment in the networking scene both have CSFB capability, the terminal equipment is currently connected with the base station B, and the cell in which the base station B is located is the network equipment of the terminal equipment.

An exemplary embodiment of the present disclosure provides an electronic device for implementing a circuit domain fallback method. The electronic device comprises at least a processor and a memory for storing executable instructions of the processor, the processor being configured to perform the circuit domain fallback method via execution of the executable instructions.

The electronic device may be implemented in various forms, and may include, for example, a mobile device such as a mobile phone, a tablet computer, a notebook computer, a Personal Digital Assistant (PDA), a navigation device, a wearable device, an unmanned aerial vehicle, and a stationary device such as a desktop computer and a smart television.

The following takes the terminal device 200 in fig. 2 as an example, and exemplifies the configuration of the electronic device. It will be appreciated by those skilled in the art that the configuration of figure 2 can also be applied to fixed type devices, in addition to components specifically intended for mobile purposes. In other embodiments, terminal device 200 may include more or fewer components than shown, or combine certain components, or split certain components, or a different arrangement of components. The illustrated components may be implemented in hardware, software, or a combination of software and hardware. The interfacing relationship between the components is shown schematically and does not constitute a structural limitation of the terminal device 200.

As shown in fig. 2, the terminal device 200 may specifically include: the mobile terminal includes a processor 210, an internal memory 221, an external memory interface 222, a USB interface 230, a charging management Module 240, a power management Module 241, a battery 242, an antenna 1, an antenna 2, a mobile communication Module 250, a wireless communication Module 260, an audio Module 270, a speaker 271, a microphone 272, a microphone 273, an earphone interface 274, a sensor Module 280, a display screen 290, a camera Module 291, a pointer 292, a motor 293, a button 294, a Subscriber Identity Module (SIM) card interface 295, and the like. The sensor module 280 may include a depth sensor 2801, a pressure sensor 2802, a gyroscope sensor 2803, a barometric pressure sensor 2804, and the like.

Processor 210 may include one or more processing units, and the various processing units may be stand-alone devices or may be integrated within one or more processors.

The wireless communication function of the terminal device 200 may be implemented by the antenna 1, the antenna 2, the mobile communication module 250, the wireless communication module 260, 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 device 200 may be used to cover a single or multiple communication bands. Different antennas can also be multiplexed to improve the utilization of the antennas.

The wireless communication module 260 may provide a wireless communication solution applied to the terminal device 200, and may be one or more devices integrating at least one communication processing module.

The external memory interface 222 may be used to connect an external memory card, such as a Micro SD card, to extend the memory capability of the terminal device 200.

Internal memory 221 may be used to store computer-executable program code, including instructions. The internal memory 221 may include a program storage area and a data storage area. Wherein the storage program area may store an operating system, an application program required for at least one function, and the like. The storage data area may store data created during use of the terminal device 200, and the like. The processor 210 executes various functional applications of the terminal device 200 and data processing by executing instructions stored in the internal memory 221 and/or instructions stored in a memory provided in the processor.

The mobile terminal 200 may implement an audio function through the audio module 270, the speaker 271, the receiver 272, the microphone 273, the earphone interface 274, the application processor, and the like. Such as music playing, recording, voice calls, etc. Audio module 270 is used to convert digital audio information into an analog audio signal output and also to convert an analog audio input into a digital audio signal. Audio module 270 may also be used to encode and decode audio signals. The speaker 271 is used for converting the audio electric signal into a sound signal. The receiver 272 is used to convert the audio electrical signal into a sound signal. A microphone 273 for converting a sound signal into an electric signal. A headset interface 274 for connecting a wired headset.

The terminal device 200 may support one or more SIM card interfaces 295 for connecting a SIM card, so that the terminal device 200 interacts with a network through the SIM card to implement functions such as communication and data communication.

The circuit domain fall-back method and the circuit domain fall-back device according to the exemplary embodiments of the present disclosure are specifically described below. Fig. 3 shows a flow diagram of a circuit domain fallback method, as shown in fig. 3, the circuit domain fallback method at least includes the following steps:

step S310: receiving a first indication message sent by network equipment, wherein the first indication message comprises information of a fallback cell;

step S320: when the fallback cell is determined to be a cell corresponding to the non-circuit domain network according to the information of the fallback cell, ignoring the first indication message;

step S330: and selecting a cell corresponding to the circuit domain network as a target fallback cell, and trying to reside in the target fallback cell to carry out voice call.

In the circuit switched fallback method in the embodiment of the disclosure, when the fallback cell in the first indication message is a cell corresponding to the non-circuit switched domain network, the terminal device can ignore the first indication message, actively select a cell corresponding to the candidate circuit switched domain network, and determine the target fallback cell. The method and the device avoid the circuit domain fallback failure caused by switching the terminal device to the cell corresponding to the non-circuit domain network according to the first indication message of the network device, thereby reducing the waiting time for accessing the voice call, improving the success rate of establishing the voice call connection and improving the user experience.

It should be noted that, in the embodiment of the present disclosure, an execution main body of the circuit switched fallback method is a terminal device, the terminal device is an LTE terminal based on a CSFB technique, the LTE terminal resides on an LTE network at ordinary times, and when a voice call needs to be performed, the terminal device falls back to the circuit switched domain of the 2G/3G network through the CSFB technique to complete a current voice call service, that is, the terminal device does not reside on the LTE network and the 2G/3G network at the same time. In addition, the terminal equipment can support an LTE network, a 5G network and a 2G/3G network, and is positioned in an area covered by the LTE network, the 5G network and the 2G/3G network in an overlapping mode.

In order to make the technical solution of the present disclosure clearer, each step of the circuit domain fallback method is explained next.

In step S310, a first indication message of the network device is received, where the first indication message includes information of a fallback cell.

In an exemplary embodiment of the present disclosure, the network device may be a base station corresponding to an LTE network to which the terminal device currently accesses. Such as base station B in fig. 1. Before falling back to the 2G/3G network, the terminal equipment resides in a cell corresponding to the network equipment. The cell corresponding to the network device may be a cell allocated by the base station corresponding to the LTE network to which the terminal device registers the LTE network with the corresponding base station before the circuit switched fallback.

In the exemplary embodiment of the disclosure, when a network device receives a call request or a CSFB request initiated by a terminal device and directed to another terminal device, or the network device receives a call request or a CSFB request sent by another terminal device and directed to the terminal device, the network device enters a CSFB procedure, sends a first indication message to the terminal device, and the terminal device receives the first indication message sent by the network device.

Specifically, the first indication message may be a handover message or a redirection message, and the network device may send the first indication message to the terminal device in two ways. The first is a handover message sent through RRC Connection Reconfiguration (RRC Connection Reconfiguration), where the handover message carries information of a fallback cell; the second is a redirection message (redirectedarririnfo) sent through RRC connection release (RRC connection release), which carries information of the fallback cell.

That is to say, the terminal device receives a first indication message sent by the network device, and the first indication message includes: the terminal equipment receives a redirection message which is sent by the network equipment through RRC connection and carries the fallback cell, or the terminal equipment receives a switching message which is sent by the network equipment through RRC connection and carries the fallback cell.

The first indication message includes information of the fallback cell, where the information of the fallback cell may include a unique identifier of a cell, such as a frequency point of the fallback cell, a cell number of the fallback cell, a cell ID of the fallback cell, and a Location Area Identity (LAI) of the fallback cell, and may also include information of a cell type of the fallback cell.

For example, the cell number of the 4G network is denoted by ECI, and the cell number of the 2G network is denoted by CI. The cell type may include a 2G cell, a 3G cell, a 4G cell, a 5G cell, etc., wherein the 2G cell may include a GSM cell, a CDMA cell, a GERAN cell, etc.; the 3G cells may include CDMA2000 cells, WCDMA cells, TD-SCDMA cells, UTRA cells, etc.; the 4G cells can comprise an EUTRAN cell, a TD-LTE cell, an FDD-LTE cell, an LTE cell and the like; the 5G cells may include NR cells and the like. Of course, as the network is updated, the cell types may also include other types, which the present disclosure does not specifically limit.

In step S320, when it is determined that the fallback cell is the cell corresponding to the non-circuit domain network according to the information of the fallback cell, the first indication message is ignored.

In the exemplary embodiment of the disclosure, since the network device corresponding to the LTE network may have a network anomaly or an unreasonable network architecture. In order to ensure that the terminal device successfully falls back to the 2G/3G network from the LTE network, after receiving a first indication message sent by the network device, the terminal device judges whether the falling cell is a cell corresponding to the circuit switched domain network according to the information of the falling cell.

Specifically, according to a preset mapping relationship, whether the fallback cell is a cell corresponding to the circuit switched domain network is judged according to the cell type or the unique identifier of the fallback cell. The preset mapping relationship may include a circuit domain network, a cell type and/or a unique identifier of a cell corresponding to the circuit domain network, and may also include a non-circuit domain network, and a cell type and/or a unique identifier of a cell corresponding to the non-circuit domain network.

The fallback cells include a cell corresponding to the circuit domain network and a cell corresponding to the non-circuit domain network, the cell corresponding to the circuit domain network may include a 2G cell and a 3G cell, and the cell corresponding to the non-circuit domain network may include a 4G cell and a 5G cell. The predetermined mapping relationship is configured in advance according to a network architecture, and the disclosure does not specifically limit specific contents in the predetermined mapping relationship.

Respectively matching the cell type of the fallback cell with the cell type of a cell corresponding to a circuit domain network and the cell type of a cell corresponding to a non-circuit domain network in a preset mapping relation, and if the cell type of the fallback cell is matched with the cell type corresponding to the circuit domain network, namely the cell type of the fallback cell is a 2G cell or a 3G cell, judging that the fallback cell is the cell corresponding to the circuit domain network; and if the cell type of the fallback cell is matched with the cell type of the cell corresponding to the non-circuit domain network, namely the cell type of the fallback cell is a 4G cell or a 5G cell, judging that the fallback cell is the cell corresponding to the non-circuit domain network. Or if the cell type of the fallback cell is an NR cell, determining that the fallback cell is a cell corresponding to the non-circuit domain network; and if the cell type of the fallback cell is an UTRA cell or a GERAN cell, determining that the fallback cell is a cell corresponding to the circuit domain network.

In addition, the fallback cell can be judged to be a cell corresponding to the circuit domain network or a cell corresponding to the non-circuit domain network according to the unique identifier of the fallback cell. The determination method is the same as the determination method according to the cell type of the fallback cell, and is not described herein again.

In the exemplary embodiment of the disclosure, if the fallback cell is a cell corresponding to the non-circuit domain network, the first indication message is ignored, and the RRC connection is actively released, that is, the terminal device performs a local release RRC action.

In an exemplary embodiment of the present disclosure, when a fallback cell is a cell corresponding to a circuit switched network, a target fallback cell is determined in the fallback cell. If the number of the fallback cells is one, taking the fallback cell as a target fallback cell and trying to reside; and if the number of the fallback cells is multiple, sequencing the multiple fallback cells according to the signal strength of each fallback cell, and configuring the fallback cell with the strongest signal as the target fallback cell.

In addition, the first indication message may further include the signal strength of the fallback cells, and the signal strength of the fallback cells in the first indication message may be sorted; the fallback cells can also be measured according to the frequency points of the fallback cells in the first indication message to obtain the updated signal strength of the fallback cells, and the fallback cells are sequenced according to the updated signal strength of the fallback cells.

Continuing to refer to fig. 3, in step S330, a cell corresponding to the cs domain network is selected as a target fallback cell, and the cell is attempted to camp on the target fallback cell for performing a voice call.

In an exemplary embodiment of the present disclosure, fig. 4 is a flowchart illustrating a method for determining a target fallback cell, and as shown in fig. 4, in step S410, it is determined whether the fallback cell is a cell corresponding to a circuit switched domain network according to information of the fallback cell; in step S420, when the fallback cell is a cell corresponding to the cs network, determining a target fallback cell in the fallback cell according to the signal strength of the fallback cell; in step S430, when the fallback cell is a cell corresponding to the non-circuit domain network, the terminal device actively selects a cell corresponding to the circuit domain network as the target fallback cell.

In an exemplary embodiment of the present disclosure, historical circuit switched fallback information may be acquired, and a cell corresponding to a circuit switched network is selected as a candidate fallback cell according to the historical circuit switched fallback information; and determining a target fallback cell in the candidate fallback cells according to a preset condition.

The historical circuit switched fallback information may include the inter-system systems fallback when the historical circuit switched fallback is successfully completed, and/or include the information of the historical fallback cells fallback when the historical circuit switched fallback is successfully completed. The different system types returned by the history circuit switched fallback when the historical circuit switched fallback is successful may include a 2G network or a 3G network, and the history fallback cell may include a 2G cell or a 3G cell. The historical circuit switched fallback information may further include information such as call start time, source IP address, destination IP address, and terminal device identifier, which is not specifically limited by this disclosure.

In addition, the terminal equipment can record and store the circuit switched fallback information after the circuit switched fallback is successful each time. For example, the information may be stored in an internal memory, so that the next cs fallback procedure calls cs fallback information to select a new fallback cell.

In the exemplary embodiment of the present disclosure, neighboring cell frequency point search may be performed in the inter-system, and a candidate fallback cell may be selected according to a search result.

Specifically, the neighboring cell frequency point search may be performed in the different system systems that are dropped when the last circuit domain drop is successfully completed, that is, the terminal device searches for the 2G/3G cell. And performing full-band search in the different system types returned when the circuit switched fallback is successfully completed last time to obtain a plurality of 2G/3G cells.

And further, judging whether the signal strength of each 2G/3G cell is greater than a threshold value, and if the signal strength of the 2G/3G cell is greater than the threshold value, taking the 2G/3G cell as a candidate fallback cell. And screening a plurality of searched 2G/3G cells according to other indexes, and configuring the 2G/3G cells meeting the indexes as candidate fallback cells. The other indicators may be indicators that meet a network standard, for example, the WCDMA network standard may be based on the RSCP or Ec/N0 indicators, the TD-SCDMA network standard is based on the RSCP indicators, and the GSM, GPRS, and EDGE network standards are based on the RSSI indicators, which is not specifically limited in this disclosure.

The circuit switched fallback method can search in the different system types which are fallback when the historical circuit switched fallback is successfully completed so as to select a new fallback cell, the success rate of searching the 2G/3G cell is guaranteed, the success rate of circuit switched fallback is further improved, the call waiting time is shortened, and the user experience is improved.

In an exemplary embodiment of the present disclosure, the signal strength of a history fallback cell is measured according to the information of the history fallback cell, and a candidate fallback cell is selected according to the signal strength of the history fallback cell.

Specifically, the signal strength of the history fallback cell may be measured according to the frequency point information of the history fallback cell, and when the signal strength is greater than the threshold value, the history fallback cell is used as a candidate fallback cell.

According to the circuit switched fallback method, the terminal equipment determines the candidate fallback cells in the historical fallback cells directly, and then determines the target fallback cells and tries to reside, so that the circuit switched fallback time is shortened.

In an exemplary embodiment of the present disclosure, fig. 5 shows a flowchart of a method for determining a candidate fallback cell, and as shown in fig. 5, in step S510, a neighboring cell frequency point search is performed in an inter-system, and a first candidate cell corresponding to a circuit domain network is selected according to a search result; in step S520, measuring the signal strength of the history fallback cell according to the information of the history fallback cell, and selecting a second candidate cell corresponding to the circuit switched domain network according to the signal strength of the history fallback cell; in step S530, the first candidate cell and the second candidate cell are configured as candidate fallback cells.

Step S510 may be executed first and then step S520 is executed, step S520 may be executed first and then step S510 is executed, and step S510 and step S520 may also be executed at the same time, which is not specifically limited by the present disclosure.

It should be noted that the method for obtaining the first candidate cell is the same as the method for selecting the candidate fallback cell according to the search result in the above embodiment, and the method for obtaining the second candidate cell is the same as the method for selecting the candidate fallback cell according to the signal strength of the historical fallback cell in the above embodiment, which is not described herein again.

In an exemplary embodiment of the present disclosure, the number of candidate fallback cells may include a plurality of candidate fallback cells, and the target fallback cell is determined among the plurality of candidate fallback cells according to a preset condition.

The preset condition may be to determine the candidate fallback cell with the strongest signal as the target fallback cell. Specifically, the candidate fallback cells are ranked according to the signal strength of the candidate fallback cells, and the candidate fallback cell with the strongest signal is configured as the target fallback cell.

In addition, the preset condition may also be that the candidate fallback cell with the most stable signal is determined as the target fallback cell, and the preset condition is not specifically limited by the present disclosure.

In an exemplary embodiment of the present disclosure, fig. 6 shows a flowchart of a method for attempting to camp on a target fallback cell, as shown in fig. 6, in step S610, system information of the target fallback cell is read; in step S620, determining whether the target fallback cell meets the camping condition according to the system information of the target fallback cell; in step S630, when the target fallback cell satisfies the camping condition, camping in the target fallback cell and initiating access; in step S640, when the target fallback cell does not satisfy the camping condition, a new target fallback cell is selected.

Specifically, selecting a new target fallback cell may be reselecting the target fallback cell according to a preset condition among the candidate fallback cells. For example, a candidate fallback cell having a signal strength second only to the target fallback cell is selected as the new target fallback cell.

The system information of the cell includes cell frequency point information, a circuit domain service load state, a cell ID, a Public Land Mobile Network (PLMN), a Location Area Code (LAC), a minimum access level, and other information. The camping condition that the target fallback cell needs to satisfy may include one or more of the following conditions: first, the PLMN where the cell is located needs to satisfy one of the following conditions: a selected PLMN; a registered PLMN; equivalent plmn (eplmn); second, the cell is not barred; thirdly, the cell belongs to at least one tracking area which is not forbidden to roam; fourth, the cell meets S criteria, etc.

In an exemplary embodiment of the disclosure, before receiving a first indication message sent by a network device, receiving a heterogeneous system frequency point measurement control message sent by the network device, and selecting a circuit domain system frequency point for measurement; and sending the measurement result to the network equipment so that the network equipment returns a first indication message carrying cell information corresponding to the circuit domain network.

Specifically, after receiving a heterogeneous system frequency point measurement control message sent by a network device, a terminal device selects to measure a frequency point of a 2G/3G cell, and sends information of the measured 2G/3G cell to the network device, so that the network device selects a fallback cell in the 2G/3G cell and sends a first indication message carrying the fallback cell to the terminal device. .

In addition, after the terminal equipment sends out the circuit domain fallback request, the measurement of the non-circuit domain system frequency point is stopped no matter whether the inter-system frequency point measurement control message sent by the network equipment is received or not. In the circuit switched fallback process, the terminal device only measures the frequency point of the circuit switched system, and the first indication message sent by the network device is guaranteed not to carry information of a cell corresponding to the non-circuit switched network.

In addition, the terminal equipment can also be set to stop measuring the 5G cell so as to ensure the success rate of the circuit switched fallback.

In an exemplary embodiment of the present disclosure, when the fallback cell is a cell corresponding to the non-circuit domain network, the network device is disabled and recorded.

Specifically, the terminal device determines that the fallback cell is a cell corresponding to the non-circuit domain network, and then determines that the network device has a network abnormal condition caused by unreasonable network design. The terminal device disables the network device and records the network device in a disabled network device list.

In addition, the information of the network equipment can be shared to the server through a big data technology, so that other terminal equipment can also acquire the network equipment which is forbidden currently in real time.

In an exemplary embodiment of the present disclosure, in response to a next voice call request, it is determined whether a network device is a disabled network device; and when the network equipment is the forbidden network equipment, selecting the cell corresponding to the circuit domain network as the target fallback cell.

Specifically, when the terminal device performs the next voice call, a forbidden network device list is obtained first, and whether the network device is a forbidden network device is judged; if the network device is a forbidden network device, the terminal device may actively select a cell corresponding to the circuit domain network as a candidate fallback cell, and determine a target fallback cell in the candidate fallback cells.

In an exemplary embodiment of the present disclosure, when the voice call is ended, the target fallback cell is switched to a first cell, where the first cell is a cell determined according to the first indication message. Because the network equipment has network abnormality, in order to avoid normal communication of the terminal equipment, when the voice call is finished, the terminal equipment is directly switched from the target fallback cell to the cell corresponding to the first indication message, and the terminal equipment is prevented from continuously communicating with the network equipment with the network abnormality.

For example, the terminal device receives a first indication message carrying a 5G cell sent by the network device, and the terminal device actively selects a cell corresponding to the circuit domain network as a target fallback cell, tries to camp on the target fallback cell, and performs a voice call. After the voice call is finished, the terminal equipment selects the 5G cell carried in the first indication message and tries to camp.

In addition, the network device may not send the first indication message to the terminal device, or the first indication message sent by the network device to the terminal device does not carry information of the fallback cell. Therefore, after the terminal device sends the call request or the CSFB request to the network device, if the first indication message returned by the network device is not received or the first indication message carrying the fallback cell returned by the network device is not received within the preset time period, the terminal device actively selects the 2G/3G cell, determines the target fallback cell among the plurality of 2G/3G cells, and tries to camp on and access the target fallback cell.

Next, taking the specific application scenario shown in fig. 7 as an example, the flow of the circuit domain fallback method is completely described, as shown in fig. 7, the circuit domain fallback method in the specific application scenario includes the following steps:

in step S710, the terminal device sends a circuit switched fallback request to the network device, and receives a first indication message of the network device, where the first indication message includes information of a fallback cell;

for example, the first indication message may be that the network device sends RRC connection release information with redirected courierinfo of GERAN/UTRA cell or NR cell to the terminal device; it may also be that the RRC Connection Reconfiguration message sent by the network device instructs the terminal device to handover to a GERAN/UTRA cell or an NR cell.

In step S720, when it is determined that the fallback cell is the NR cell according to the information of the fallback cell, ignoring the first indication message;

in step S730, the terminal device actively acquires historical circuit switched fallback information, searches according to the historical circuit switched fallback information, and determines a plurality of 2G/3G cells as candidate fallback cells;

in step S740, the candidate fallback cell with the strongest signal strength is used as the target fallback cell;

in step S750, when it is determined that the target fallback cell meets the camping condition according to the system information of the target fallback cell, camping on the target fallback cell and initiating access;

in step S760, a voice call is performed in the target fallback cell;

in step S770, after the voice call is finished, the target fallback cell is handed over to the NR cell.

The circuit switched fallback method in the embodiment of the disclosure avoids the problem that the call waiting time is too long or the call fails due to the fact that the terminal device is mechanically redirected or switched to the NR cell according to the protocol requirements in the CSFB process, improves the success rate of the circuit switched fallback in the abnormal network, and improves the call experience of the user.

Those skilled in the art will appreciate that all or part of the steps implementing the above embodiments are implemented as computer programs executed by a CPU. When executed by the CPU, performs the functions defined by the above-described methods provided by the present disclosure. The program may be stored in a computer readable storage medium, which may be a read-only memory, a magnetic or optical disk, or the like.

Furthermore, it should be noted that the above-mentioned figures are only schematic illustrations of the processes involved in the methods according to exemplary embodiments of the present disclosure, and are not intended to be limiting. It will be readily understood that the processes shown in the above figures are not intended to indicate or limit the chronological order of the processes. In addition, it is also readily understood that these processes may be performed synchronously or asynchronously, e.g., in multiple modules.

Embodiments of the disclosed apparatus are described below, which can be used to implement the circuit domain fallback method described above in the present disclosure. For details not disclosed in the embodiments of the apparatus of the present disclosure, please refer to the embodiments of the circuit domain fallback method described above in the present disclosure.

Fig. 8 schematically illustrates a block diagram of a circuit domain fall back apparatus according to one embodiment of the present disclosure.

Referring to fig. 8, according to a circuit domain fall-back device 800 of an embodiment of the present disclosure, the circuit domain fall-back device 800 includes: a message receiving module 801, a message ignoring module 802 and a selective residing module 803. Specifically, the method comprises the following steps:

a message receiving module 801, configured to receive a first indication message sent by a network device, where the first indication message includes information of a fallback cell;

a message ignoring module 802, configured to ignore the first indication message when determining, according to the information of the fallback cell, that the fallback cell is a cell corresponding to the non-circuit domain network;

the selective residing module 803 is configured to select a cell corresponding to the circuit domain network as a target fallback cell, and attempt to reside in the target fallback cell to perform a voice call.

In an exemplary embodiment of the present disclosure, the message receiving module 801 may also be configured to receive a redirection message carrying a fallback cell, which is sent by a network device through radio resource control; or receiving a switching message which is sent by the network equipment through the radio resource control and carries the fallback cell.

In an exemplary embodiment of the present disclosure, the selective residing module 803 may further be configured to obtain historical circuit domain fallback information, and select a cell corresponding to the circuit domain network as a candidate fallback cell according to the historical circuit domain fallback information; and determining a target fallback cell in the candidate fallback cells according to a preset condition.

In the exemplary embodiment of the present disclosure, the selective camping module 803 may also be configured to perform neighboring cell frequency point search in the inter-system, and select a candidate fallback cell according to a search result. The historical circuit switched fallback information comprises different system systems which are fallback when the historical circuit switched fallback is successfully completed.

In an exemplary embodiment of the present disclosure, the selective parking module 803 may be further configured to measure the signal strength of the history fallback cells according to the information of the history fallback cells, and select the candidate fallback cells according to the signal strength of the history fallback cells. The historical circuit switched fallback information comprises information of a historical fallback cell which is fallback when the historical circuit switched fallback is successfully completed.

In an exemplary embodiment of the present disclosure, the selective parking module 803 may be further configured to rank the candidate fallback cells according to the signal strength of the new fallback cell, and configure the candidate fallback cell with the strongest signal as the target fallback cell.

In an exemplary embodiment of the present disclosure, the selective camping module 803 may also be used to read system information of the target fallback cell; judging whether the target fallback cell meets the residence condition or not according to the system information of the target fallback cell; when the target fallback zone meets the residence condition, the target fallback zone resides in the target fallback zone and initiates access; and when the target fallback zone does not meet the residence condition, selecting a new target fallback zone.

In an exemplary embodiment of the present disclosure, the circuit domain fallback apparatus 800 may further include a measurement cell module (not shown in the figure), where the measurement cell module may be configured to receive an inter-system frequency point measurement control message sent by a network device before receiving a first indication message of the network device, and select a circuit domain system frequency point for measurement; and sending the measurement result to the network equipment so that the network equipment returns the first indication message of the cell corresponding to the carrying circuit domain network.

In an exemplary embodiment of the present disclosure, the circuit switched fallback apparatus 800 may further include an definitely forbidden cell module (not shown in the figure), and the forbidden cell module may be configured to forbid and record the network device when the fallback cell is a cell corresponding to the non-circuit switched network.

In an exemplary embodiment of the present disclosure, the circuit domain fallback apparatus 800 may further include a forbidden cell determining module (not shown in the figure), where the forbidden cell determining module may be configured to determine whether the network device is a forbidden network device in response to the next voice call request; and when the network equipment is the forbidden network equipment, selecting the cell corresponding to the circuit domain network as the target fallback cell.

In an exemplary embodiment of the present disclosure, the circuit switched fallback apparatus 800 may further include a cell determining module (not shown in the figure), and the cell determining module may be configured to determine a target fallback cell in the fallback cell when the fallback cell is a cell corresponding to the circuit switched network.

In an exemplary embodiment of the present disclosure, the circuit switched fallback apparatus 800 may further include a returning cell module (not shown in the figure), which may be configured to switch from the target fallback cell to a first cell when the voice call is ended, where the first cell is a cell determined according to the first indication message.

The specific details of each circuit domain fallback apparatus are already described in detail in the corresponding circuit domain fallback method, and therefore are not described herein again.

It should be noted that although in the above detailed description several modules or units of the apparatus for performing are mentioned, such a division is not mandatory. Indeed, the features and functionality of two or more modules or units described above may be embodied in one module or unit, according to embodiments of the present disclosure. Conversely, the features and functions of one module or unit described above may be further divided into embodiments by a plurality of modules or units.

In an exemplary embodiment of the present disclosure, an electronic device capable of implementing the above method is also provided.

As will be appreciated by one skilled in the art, aspects of the present disclosure may be embodied as a system, method or program product. Accordingly, various aspects of the present disclosure may be embodied in the form of: an entirely hardware embodiment, an entirely software embodiment (including firmware, microcode, etc.) or an embodiment combining hardware and software aspects that may all generally be referred to herein as a "circuit," module "or" system.

Exemplary embodiments of the present disclosure also provide a computer-readable storage medium having stored thereon a program product capable of implementing the above-described method of the present specification. In some possible embodiments, various aspects of the disclosure may also be implemented in the form of a program product including program code for causing a terminal device to perform the steps according to various exemplary embodiments of the disclosure described in the above-mentioned "exemplary methods" section of this specification, when the program product is run on the terminal device, for example, any one or more of the steps in fig. 3 to 7 may be performed.

Exemplary embodiments of the present disclosure also provide a program product for implementing the above method, which may employ a portable compact disc read only memory (CD-ROM) and include program code, and may be run on a terminal device, such as a personal computer. However, the program product of the present disclosure is not limited thereto, and in this document, a readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

The readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

A computer readable signal medium may include a propagated data signal with readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated data signal may take many forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A readable signal medium may also be any readable medium that is not a readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Program code for carrying out operations for the present disclosure may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C + + or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., through the internet using an internet service provider).

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

1. A circuit switched fallback method is applied to terminal equipment and is characterized by comprising the following steps:

receiving a first indication message sent by network equipment, wherein the first indication message comprises information of a fallback cell;

when the fallback cell is determined to be a cell corresponding to a non-circuit domain network according to the information of the fallback cell, ignoring the first indication message;

and selecting a cell corresponding to the circuit domain network as a target fallback cell, and trying to reside in the target fallback cell to carry out voice call.

2. The circuit switched fallback method of claim 1, wherein receiving the first indication message sent by the network device comprises:

receiving a redirection message which is sent by the network equipment through wireless resource control and carries the fallback cell; or

And receiving a switching message which is sent by the network equipment through wireless resource control and carries the fallback cell.

3. The cs fallback method of claim 1, wherein selecting a cell corresponding to the cs network as the target fallback cell comprises:

obtaining historical circuit domain fallback information, and selecting a cell corresponding to the circuit domain network as a candidate fallback cell according to the historical circuit domain fallback information;

and determining the target fallback cell in the candidate fallback cells according to a preset condition.

4. The circuit switched fallback method according to claim 3, wherein the historical circuit switched fallback information includes a different system type that is fallback when the historical circuit switched fallback is successfully completed;

selecting a cell corresponding to the circuit switched domain network as a candidate fallback cell according to the historical circuit switched domain fallback information, wherein the selecting comprises:

and searching adjacent cell frequency points in the different system modes, and selecting the candidate fallback cells according to the search result.

5. The CS domain fallback method according to claim 3, wherein the historical CS domain first indication message comprises information of a historical fallback cell that is fallback when the historical CS domain fallback is successfully completed;

and measuring the signal intensity of the historical fallback cells according to the information of the historical fallback cells, and selecting the candidate fallback cells according to the signal intensity of the historical fallback cells.

6. The CS domain fallback method according to claim 3, wherein determining the target fallback cell among the candidate fallback cells according to a preset condition comprises:

and sequencing the candidate fallback cells according to the signal strength of the candidate fallback cells, and configuring the candidate fallback cell with the strongest signal as the target fallback cell.

7. The cs fallback method of claim 1, wherein attempting to camp on the target fallback cell comprises:

reading system information of the target fallback cell;

judging whether the target fallback cell meets a residence condition or not according to the system information of the target fallback cell;

when the target fallback cell meets the residence condition, the target fallback cell resides in the target fallback cell and initiates access;

and when the target fallback zone does not meet the residence condition, selecting a new target fallback zone.

8. The circuit domain fallback method according to claim 1, wherein before receiving the first indication message sent by the network device, the method further comprises:

receiving a different system frequency point measurement control message sent by the network equipment, and selecting a circuit domain system frequency point for measurement;

and sending the measurement result to the network equipment so that the network equipment returns a first indication message carrying a cell corresponding to the circuit domain network.

9. The circuit domain fallback method according to claim 1, further comprising:

and when the fallback cell is the cell corresponding to the non-circuit switched domain network, disabling and recording the network equipment.

10. The circuit domain fallback method according to claim 9, further comprising:

responding to the voice call request of the next time, and judging whether the network equipment is forbidden network equipment or not;

and when the network equipment is the forbidden network equipment, selecting a cell corresponding to the circuit domain network as the target fallback cell.

11. The circuit domain fallback method according to claim 1, further comprising:

and when the fallback cell is a cell corresponding to the circuit domain network, determining the target fallback cell in the fallback cell.

12. The circuit domain fallback method according to claim 1, further comprising:

and when the voice call is finished, switching from the target fallback cell to a first cell, wherein the first cell is determined according to the first indication message.

13. A circuit switched fall back apparatus, comprising:

a message receiving module, configured to receive a first indication message of a network device, where the first indication message includes information of a fallback cell;

a message ignoring module, configured to ignore the first indication message when determining, according to the information of the fallback cell, that the fallback cell is a cell corresponding to a non-circuit domain network;

and the selective residing module is used for selecting the cell corresponding to the circuit domain network as a target fallback cell and trying to reside in the target fallback cell to carry out voice communication.

14. A computer-readable storage medium on which a computer program is stored, the program, when executed by a processor, implementing the circuit domain fallback method according to any one of claims 1 to 12.

15. An electronic device, comprising:

one or more processors;

storage means for storing one or more programs that, when executed by the one or more processors, cause the one or more processors to implement the circuit domain fallback method as claimed in any one of claims 1 to 12.