WO2012113214A1

WO2012113214A1 - Method, related system and device for keeping cs domain of single-card dual-standby terminal residing in two networks simultaneously

Info

Publication number: WO2012113214A1
Application number: PCT/CN2011/078988
Authority: WO
Inventors: 郑小春; 曾雪红; 徐龙; 孙炼
Original assignee: 华为技术有限公司
Priority date: 2011-02-21
Filing date: 2011-08-26
Publication date: 2012-08-30
Also published as: CN102137459B; CN102137459A

Abstract

Provided are a method,related system and device for keeping the CS domain of a single-card dual-standby terminal residing in two networks simultaneously. The method is applied at the network side and includes: receiving 2G and 3G network location update requests sent by a single-card terminal, with the requests carrying the same user ID; completing CS domain location update together with the terminal so that the CS domain of the terminal resides in 2G and 3G networks, and saving the location information about the networks resided in by the terminal; when receiving a CS domain service request sent by the calling user, preferably selecting the 2G network to execute the CS domain service according to the saved 2G location information, but when there is no 2G network location information or the 2G network cannot meet the requirement of the CS domain service, selecting the 3G network to execute the CS domain service according to the saved 3G location information. By way of the above solution, the UE resides in two networks simultaneously, and preferentially selects the 2G network to execute the CS domain service, avoiding frequent reselection between the 2G network and the 3G network, and improving the communication quality.

Description

Single card dual standby terminal CS domain simultaneously camping on two networks and related systems and devices

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method, a related system, and a device for simultaneously camping two networks in a CS domain of a single card dual standby terminal. Background technique

With the development of communication technologies, 3G (3rd-generation, third-generation communication technologies, such as WCDMA, TD-SCDMA, etc.), LTE (Long Term Evolution), WLAN (Wireless Local Area Networks), etc. High-speed data transmission communication networks are becoming more and more widely used. These networks are characterized by the ability to provide high-speed data services, while others also support voice services. For example, 3G networks can support voice services while providing high-speed data services.

Most of the current 3G terminals are 2G/3G dual-mode phones, such as WCDMA/GSM dual-mode, TD-SCDMA/GSM dual-mode phones. When the existing 2G/3G dual-mode terminal performs communication services, it usually resides on the 3G network preferentially. When the 3G network has no signal, it will reselect the 2G (second generation communication technology) network (such as the GSM network). ), re-select to the 3G network when the 3G network signal is restored.

However, the existing 2G network coverage is good, and the 3G network often has a poor coverage level, especially the indoor 3G signal is not good. Therefore, when the communication service is performed, it is easy for the 3G terminal to frequently reselect between the 2G network and the 3G network. In the process of reselection between the 2G network and the 3G network, it is easy to cause missed calls, thereby affecting the communication quality of the voice service. Summary of the invention

The embodiments of the present invention provide a method for a CS-domain of a single-card dual-standby terminal to simultaneously camp on two networks, and related systems and devices, so as to improve the communication quality of the voice service of the 3G terminal. The embodiment of the present invention provides a method for a CS-domain of a single-card dual-standby terminal to simultaneously reside on two networks, and is applied to a single SIM card terminal, where the SIM card includes a user identifier, and the method includes:

Sending, to the network side, a 2G network location update request and a 3G network location update request that carry the same user identifier, so that the network side receives the 2G network location update request and the 3G network location update request, and the terminal Completing the circuit switched CS domain location update process together, so that the CS domain of the terminal resides on the 2G network and the 3G network;

When the CS domain service request is initiated, the 2G network is preferentially selected to perform the CS domain service. When the 2G network does not meet the CS domain service requirement, the 3G network is selected to perform the CS domain service.

The embodiment of the present invention further provides a method for a CS-domain of a single-card dual-standby terminal to simultaneously reside on the network, and is applied to the network side, including:

Receiving a 2G network location update request and a 3G network location update request sent by the terminal, where the terminal is a single SIM card terminal, the SIM card includes a user identifier, the 2G network location update request, and the 3G network location update request Carrying the same user identifier; performing a circuit-switched CS domain location update procedure with the terminal, so that the CS domain of the terminal resides on the 2G network and the 3G network, and saves the 2G network where the terminal resides Location information and location information of the 3G network;

When receiving the CS domain service request sent by the calling user, the second domain network is preferentially selected according to the saved location information of the 2G network to perform the CS domain service, when the 2G network location information does not exist or the 2G network does not satisfy the CS When the domain service requires, the 3G network is selected to perform the CS domain service according to the saved location information of the 3G network.

The embodiment of the invention further provides a communication system, including:

2G mobile switching center MSC, 3G mobile switching center MSC, location home register HLR, and calling mobile switching center MSC;

The 2G MSC is configured to: receive a 2G network location update request sent by the terminal; The terminal is a single-user identity module SIM card, the SIM card includes a user identifier, the 2G network location update request carries the user identifier, and sends a first network location update request to the HLR, where the first network location The update request carries the user identifier, the 2G network identifier, and the 2G MSC identifier;

The 3G MSC is configured to receive a 3G network location update request sent by the terminal; the 3G network location update request also carries the user identifier; and send a second network location update request to the HLR, where the second The network location update request carries the user identifier, the 3G network identifier, and the 3G MSC identifier;

The 2G network identifier and the 3G network identifier are used to identify the type of the network where the terminal sends the location update request, and the 2G MSC identifier and the 3G MSC identifier are used to identify the MSC that receives the location update request.

The HLR is configured to save first location information according to the received first network location update request and the second network location update request, where the first location information includes a network where the terminal sends a location update request The network type and the identifier of the MSC that receives the location update request, and notifies the 2G MSC and the 3G MSC to insert user data, so that the 2G MSC and the 3G MSC save the second location information after receiving the notification, The second location information includes location area information of the network where the terminal sends the location update request; if the other MSC stores the old second location information, the MSC is notified to delete the old second location information;

The calling MSC is configured to receive a CS domain service request sent by the calling user, and query the HLR for routing information of the terminal;

The HLR is further configured to: preferentially obtain routing information from the 2G MSC according to the saved first location information; when there is no location information corresponding to the 2G network in the first location information, or the 2G network is not satisfied When the CS domain service requires, the routing information is obtained from the 3G MSC; the 2G MSC or the 3G MSC is further configured to: return the routing information to the HLR according to the saved second location information, so that the HLR Returning routing information of the terminal to the calling MSC; The calling MSC is further configured to initiate a call to the terminal to the 2G MSC that returns routing information or the 3G second location information.

2G/3G mobile switching center MSC, location home register HLR, and calling mobile switching center MSC;

The 2G/3G MSC is configured to receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single user identity module SIM card, the SIM card includes a user identifier, and the 2G network location And the update request and the 3G network location update request carry the same user identifier; send a first network location update request and a second network location update request to the HLR, where the first network location update request carries the a user identifier, a 2G network identifier, and a 2G/3G MSC identifier, where the second network location update request carries the user identifier, a 3G network identifier, and a 2G/3G MSC identifier;

The 2G network identifier and the 3G network identifier are used to identify the network type of the network where the terminal sends the location update request, and the 2G/3G MSC identifier is used to identify the MSC that receives the location update request.

The HLR is configured to: save the first location information according to the received first network location update request and the second network location update, where the first location information includes a network where the terminal sends a location update request The network type and the identifier of the MSC that receives the location update request; and notifies the 2G/3G MSC to insert the user data, and the network type is carried in the notification, so that the 2G/3G MSC saves the second location information after receiving the notification, The second location information includes the network type and location area information of a network where the terminal sends a location update request;

The HLR is further configured to: obtain routing information from the 2G/3G MSC according to the saved first location information; The 2G/3G MSC is further configured to: return routing information to the HLR, so that the HLR returns routing information of the terminal to the calling MSC;

The calling MSC is further configured to send a call connection to the 2G/3G MSC that returns routing information, and the 2G/3G MSC preferentially initiates a call to the terminal through the 2G network according to the saved second location information. When the 2G network location information does not exist in the second location information, or the 2G network does not meet the CS domain service requirement, the 2G/3G MSC initiates a call to the terminal through the 3G network according to the saved second location information.

The HLR is configured to: save the first location information according to the received first network location update request and the second network location update, where the first location information includes a network where the terminal sends a location update request And the network type and the identifier of the MSC that receives the location update request; and notifying the 2G/3G MSC to insert the user data, and the network type of the terminal is accessed when the notification is sent, so that the 2G/3G MSC saves the second location information after receiving the notification. The second location information includes the network type and location area information of a network where the terminal sends a location update request; The calling MSC is configured to receive a CS domain service request sent by the calling user, and query the HLR for routing information of the terminal;

The HLR is further configured to: preferentially obtain routing information for the 2G network from the 2G/3G MSC according to the saved first location information, where there is no location information or 2G corresponding to the 2G network in the first location information. When the network does not meet the service requirements of the CS domain, it is used to obtain routing information for the 3G network from the 2G/3G MSC;

The 2G/3G MSC is further configured to: return, to the HLR, routing information of a specified network type, so that the HLR returns routing information of the terminal to the calling MSC;

The calling MSC is further configured to send a call connection to the 2G/3G MSC that returns routing information, so that the 2G/3G MSC initiates a call to the terminal according to the saved second location information and routing information.

The embodiment of the present invention further provides a terminal, where the terminal is a single SIM card terminal, and the SIM card includes a user identifier, and the terminal includes:

a 2G processing module, configured to send, to the network side, a 2G network location update request that carries the user identifier, so that the network side completes the circuit switched CS domain location update together with the terminal after receiving the 2G network location update request a process, such that the CS domain of the terminal resides on a 2G network;

a 3G processing module, configured to send, to the network side, a 3G network location update request that carries the user identifier, so that after receiving the 3G network location update request, the network side completes a circuit switched CS domain location update with the terminal a process, such that the CS domain of the terminal resides on a 3G network;

a selection module, configured to: when the CS domain service request is initiated, preferentially select the 2G network to perform the CS domain service by using the 2G processing module, and when the 2G network does not meet the CS domain service requirement, The 3G processing module selects the 3G network to execute the CS domain service.

An embodiment of the present invention further provides an MSC, where the MSC is used for both 2G networks and a 2G/3G MSC of the 3G network, the MSC includes: a receiving module, a sending module, a route returning module, and a call selecting module;

The receiving module is configured to: receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single SIM card, the SIM card includes a user identifier, and the 2G network location update request and the 3G network location update request carry the same User identity; and the circuit switched CS domain of the terminal resides on the 2G network and the 3G network, and saves the location information of the resident 2G network and the location information of the 3G network;

The sending module is configured to send, to the HLR, a first network location update request and a second network location update request, where the first network location update request carries the user identifier, a 2G network identifier, and a 2G/3G MSC identifier, and the second network The location update request carries a user identifier, a 3G network identifier, and a 2G/3G MSC identifier;

By transmitting a first network location update request and a second network location update request,

The HLR saves the first location information according to the received first network location update request and the second network location update, where the first location information includes a network type and a receiving location of the network where the terminal sends the location update request. Update the identity of the requested MSC;

The receiving module is further configured to: receive an insertion user data notification sent by the HLR after receiving the first network location update request and the second network location update request, where the notification carries the network type of the network where the terminal sends the location update request, and receives Saving the second location information after the notification, where the second location information includes the network type and the location area information of the network where the terminal sends the location update request;

The receiving module is further configured to: receive a request for acquiring routing information sent by the HLR, where the HLR sends a request for obtaining routing information when the calling MSC queries the routing information request, and the calling MSC receives the calling user. Send a check to the HLR when sending a CS domain service request Request for routing information;

The route returning module is configured to: return, according to the request of the HLR, routing information to the HLR, so that the HLR returns the routing information of the terminal to the calling MSC;

The call selection module is configured to receive a call connection sent by the calling MSC according to the routing information, and preferentially initiate a call to the terminal through the 2G network according to the saved second location information, and when the 2G network does not meet the CS domain service requirement, according to the saved The two location information initiates a call to the terminal through 3G.

An embodiment of the present invention further provides an HLR, including: a location update receiving module, a saving module, and a route acquiring module;

The location update receiving module is configured to receive a first network location update request and a second network location update request respectively sent by the 2G mobile switching center MSC and the 3G MSC, where the first network location update request carries a user identifier, a 2G network The identifier and the 2G MSC identifier, where the second network location update request carries the user identifier, the 3G network identifier, and the 3G MSC identifier. The 2G network identifier and the 3G network identifier are used to identify the terminal corresponding to the user identifier. The type of the network where the location update request is sent, the 2G MSC identity and the 3G MSC identity are used to identify the MSC that receives the location update request;

The saving module is configured to save first location information according to the received first network location update request and the second network location update request, where the first location information includes where the terminal sends a location update request The network type of the network and the identifier of the MSC receiving the location update request; and notifying the 2G MSC and the 3G MSC to insert user data, so that the 2G MSC and the 3G MSC save the second location information after receiving the notification, The second location information includes location area information of the network where the terminal sends the location update request; if the other MSC stores the old second location information, the other MSC is notified to delete the old second location information; The information includes the identifier of the MSC of the terminal in the 2G network and the 3G network; the route obtaining module is configured to receive, by the calling MSC, a request for querying routing information of the terminal, and according to the saved first location Information to obtain routing information from the 2G MSC If the location information corresponding to the 2G network does not exist in the first location information or the 2G network does not satisfy the CS domain service requirement, obtain routing information from the 3G MSC; the calling MSC sends the received message to the calling party. Sending a request for querying routing information to the HLR when requesting a CS domain service;

The route obtaining module is further configured to: return, to the calling MSC, a routing information of the terminal

The method for the two-network dual-standby terminal CS domain to simultaneously reside on the two networks in the embodiment of the present invention, and the related system and device. After the terminal is turned on or moved, the terminal sends a 2G network location update request carrying the user identifier of the terminal to the network side. The 3G network location update request enables the terminal to reside on the 2G network and the 3G network at the same time. When the CS domain service is performed, the terminal or the network side preferentially selects the 2G network for communication, and when the 2G network does not meet the CS domain service requirement, Select 3G network for communication. In the embodiment of the present invention, the terminal resides on the 2G network and the 3G network at the same time, and the CS domain service preferentially selects the 2G network for communication. Since the 2G network generally has better coverage than the 3G network signal, the priority selection of the 2G network can be The communication quality of the CS domain service based on the voice service is improved, and the frequent reselection between the 2G network and the 3G network in the prior art is avoided, and the communication quality is improved. Meanwhile, the 2G network is not satisfied in the embodiment of the present invention. When the CS domain service requires and the 3G network can meet the CS domain service requirements, the 3G network is selected for the CS domain service. Since the terminal already resides in the 3G network, there is no need to initiate a read system message and a location update process, and the connection is not increased. Delay. DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, a brief description of the drawings to be used in the description of the embodiments will be briefly made. It is obvious that the drawings in the following description are some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in view of the drawings.

FIG. 1 is a schematic diagram of a CS-domain of a single-card dual-standby terminal simultaneously hosting two networks according to Embodiment 1 of the present invention; Flow chart of the law;

2 is a flowchart of a method for simultaneously camping two networks of a single-card dual-standby terminal CS domain according to Embodiment 2 of the present invention;

3 is a flowchart of a method for performing location update of a terminal according to Embodiment 3 of the present invention; FIG. 4A is a schematic diagram of separate deployment of a 2G CS domain core network and a 3G CS domain core network; FIG. 4B is a 2G CS domain core network and 3G CS. FIG. 5 is a flowchart of a location update process according to Embodiment 4 of the present invention;

5B is a schematic diagram of a terminal-resident core network in the embodiment shown in FIG. 5A;

FIG. 5C is a flowchart of a location update process according to Embodiment 6 of the present invention; FIG.

FIG. 5D is a schematic diagram of location update in the embodiment shown in FIG. 5C; FIG.

5E is a schematic diagram of location update in a location update process according to Embodiment 7 of the present invention; FIG. 6 is a flowchart of processing a voice called service on a network side according to Embodiment 8 of the present invention; Flow chart of the voice called flow;

7B is a flowchart of a voice called flow according to Embodiment 10 of the present invention;

7C is a flowchart of a voice called flow according to Embodiment 11 of the present invention;

8 is a flowchart of receiving a short message service according to Embodiment 12 of the present invention; FIG. 9A is a flowchart of a process for receiving a short message service according to Embodiment 13 of the present invention; FIG. 9B is a flowchart of Embodiment 14 of the present invention; FIG. 9 is a flowchart of a process for receiving a short message service according to Embodiment 15 of the present invention; FIG. 10 is a schematic diagram of a terminal according to Embodiment 16 of the present invention;

FIG. 1 is a schematic structural diagram of an MSC according to Embodiment 17 of the present invention;

FIG. 12 is a schematic structural diagram of an HLR according to Embodiment 18 of the present invention. detailed description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It is to be understood that the described embodiments are a part of the embodiments of the invention, rather than all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Embodiment 1

FIG. 1 is a flowchart of a method for simultaneously camping two networks of a single-card dual-standby terminal CS domain according to Embodiment 1 of the present invention, which is applied to a terminal (User Equipment, hereinafter referred to as UE), as shown in FIG. Includes:

Step 101: Send a 2G network location update request and a 3G network location update request that carry the same user identifier to the network side, so that after receiving the 2G network location update request and the 3G network location update request, the network side completes the CS with the UE ( Circuit Switching) The domain location update process, so that the CS domain of the UE resides on the 2G network and the 3G network;

The executor of this embodiment is a terminal (User Equipment, hereinafter referred to as UE). The UE in this embodiment may be a single-user identity module (SIM) card terminal, and the SIM card includes a user identifier, that is, the UE is a 2G/3G dual-mode terminal, the UE uses a USIM card, and the USIM is a global user identifier. The module (Universal Subscriber Identity Module) is a user card introduced by the 3G network and can be regarded as a special SIM card. In the embodiment of the present invention, the USIM card and the SIM card are not strictly distinguished.

It should be noted that, in the embodiment of the present invention, the "CS domain resides in the 2G (or 3G) network, and can also be understood as: "Connecting the CS domain to the 2G (or 3G) network", that is, the terminal initiates the LAU ( Location Area Update, the process of attaching to a 2G (or 3G) network.

After the UE is powered on or the UE's 2G and 3G network locations move, the UE sends 2G and 3G network location update requests to the network side (the sequence is not limited); specifically, the UE can move to the 2G network and the 3G network. The switching center (Mobile Switching Center, hereinafter referred to as: MSC) sends a location update request. The 2G and 3G network location update request carries the user identifier of the UE, and the UE can reside in 2G and 3G through the location update process. In the network. The user identifier may be an International Mobile Subscriber Identity (IMSI), and the network side may identify the UE by using the user identifier. In the embodiment of the present invention, the terminal uses a SIM (USIM) card, and the same user identifier is carried in the 2G network location update request and the 3G network location update request.

Through this step, the dual CS of the terminal CS domain in two different networks can be completed.

CS domain services (mainly voice services and short message services). In practical applications, in some cases, if the first network does not meet the camping condition, it may only camp on the second network, and then periodically detect whether the first network satisfies the camping condition, and when satisfied, simultaneously camps Go to the first network. For example, when the 2G signal does not meet the camping condition, the CS domain can only reside on the 3G network, and the UE periodically detects the 2G signal. When the 2G signal is recovered, the CS domain resumes to reside at the same time as the 2G network and the 3G network. To distinguish it from the standard 2G/3G "single card single standby" dual mode terminal, the UE in this embodiment may be referred to as a 2G/3G "single card dual standby" dual mode terminal.

After the resident is completed, the terminal can also save the 2G location information and the 3G location information of the resident network, which is specifically a location area in the 2G network and a location area in the 3G network, and if the terminal finds that the terminal is processed. When the location area is inconsistent with the saved location area, the location update process is initiated and resides in the current location area.

Step 102: When the CS domain service is initiated, the 2G network is preferentially selected to perform the CS domain service. When the 2G network does not meet the CS domain service requirement, the 3G network is selected to perform the CS domain service.

When the UE initiates the CS domain service, it preferentially selects the 2G network for communication according to the saved location information of the network (a certain location area in the 2G network), for example:

When the UE initiates a voice call, the UE initiates a call in the 2G network according to the saved location information of the 2G network according to the configured service selection policy, and the call flow is consistent with the standard process;

When the UE actively sends the short message, the UE sends the short message preferentially on the 2G network according to the configured service selection network policy, and the process is consistent with the standard process.

Further, if the 2G network does not meet the CS domain service requirements (such as 2G network signal is poor or If the 2G network load is too high or the video call service is not supported by the 2G network, the 3G network can be selected for communication.

Further, in consideration of reducing the impact on the existing ordinary terminal, it is necessary to distinguish the single card dual standby terminal, and the network only processes the single card dual standby terminal according to the present invention. The single-card dual-standby terminal carries the single-card dual-standby terminal identifier when the location update request is sent, so that the network recognizes the single-card dual-standby terminal and processes it.

The UE in this embodiment resides on the 2G network and the 3G network at the same time, but only one USIM card can only save one set of data, and another set of data can be saved in the storage space of the UE (such as flash memory, Flash Memory). The UE is managed on its behalf.

The data managed by the UE specifically includes:

Location-related data information, including: Location Area Information (LAI), Location Update Status;

Temporary Mobile Subscriber Identity (TMSI); network initial search parameters, such as frequency points.

In the embodiment of the present invention, after the UE is powered on or the location is moved, the UE sends a 2G network location update request and a 3G network location update request that carries the user identifier of the UE to the network, so that the UE can reside on the 2G network and the 3G network at the same time; When the CS domain service is performed, the UE preferentially selects the 2G network for communication, and if the 2G network signal does not satisfy the CS domain service requirement, the 3G network is selected for communication. In the embodiment of the present invention, when the UE camps on the 2G network and the 3G network at the same time, and the 2G network is preferentially selected for the CS domain service, since the information coverage of the 2G network is generally better than that of the 3G network, the priority selection of the 2G network can be improved. The communication quality of the voice service-based CS domain service avoids frequent reselection between the 2G network and the 3G network, improves the communication quality, and can also be used when the 2G network signal does not meet the requirements or when the video call service is used. When the 3G network is used as the backup and the 3G network is selected for the CS domain service, the UE already resides on the 3G network. Therefore, it is not necessary to initiate the read system message and the location update process, and the connection delay is not increased. Embodiment 2

2 is a flowchart of a method for simultaneously camping two networks of a single-card dual-standby terminal CS domain according to Embodiment 2 of the present invention, which is applied to the network side, as shown in FIG. 2, the method includes:

Step 201: Receive a 2G network location update request and a 3G network location update request sent by the UE, complete the CS domain location update process with the UE, so that the CS domain of the UE resides on the 2G network and the 3G network; Location information of the 2G network and location information of the 3G network.

The UE in this embodiment is a single SIM card terminal, and the SIM card contains the user identifier. The 2G network location update request and the 3G network location update request carry the same user identifier.

The execution entity of this embodiment is a related device on the network side (hereinafter referred to as the network side). After the UE is powered on or after the UE's network location moves, the UE sends a location update request to the network side; the network side receives the location update request sent by the UE, and completes the CS domain location update process with the UE, so that the CS domain of the UE is stationed. Stay on 2G networks and 3G networks.

The location update request includes the user identifier of the UE, and also carries the current location information of the UE. Specifically, after the UE is updated in the location of the 2G network, the network side receives the 2G network location update request sent by the UE; when the UE is updated in the location of the 3G network, the network side receives the 3G network location update request sent by the UE.

The UE sends a location update request to the 2G network and the 3G network, and the network side saves the 2G network location information and the 3G network location information of the UE according to the location update request, so that the UE resides in the 2G network and the 3G network at the same time.

The network side may include a network element device such as an MSC and a Home Location Register (hereinafter referred to as HLR). Receiving, by the MSC, a location update request sent by the UE, and then sending the user identifier of the UE, the network identifier, and the identifier of the MSC to the HLR; the HLR returns an indication of inserting the user data to the MSC, and then the MSC saves the location information of the UE under the network identifier. . Step 202: When receiving the CS domain service request sent by the calling user, preferentially select the 2G network to perform the CS domain service according to the saved location information of the 2G network; when there is no location information of the 2G network or the 2G network does not satisfy the CS domain service When required, the 3G network is selected to perform the CS domain service according to the saved location information of the 3G network.

The UE in this embodiment is a called user. When receiving the CS domain service request (such as a voice call service request or a short message service request), the network side preferentially selects the 2G network for communication according to the saved location information of the 2G network.

Further, if there is no location information of the 2G network or the 2G network does not meet the CS domain service requirement, the network side selects the 3G network to communicate according to the saved location information of the 3G network, for example, the network side may choose to send a voice call from the 3G network or Receive short messages.

Specifically, the location information of the 2G network and the location information of the 3G network include first location information and second location information;

The first location information includes a network type and an MSC identifier stored in the location home register HLR, where the network type is a type of the network in which the terminal sends the location update request, and the MSC identifier is an identifier of the MSC that receives the location update request.

The second location information includes the network type stored in the mobile switching center MSC (that is, the type of the network where the terminal sends the location update request) and the location area information, where the location area information is a terminal sending a location update request. The location area in the network.

In the embodiment of the present invention, after the UE is powered on or the location is moved, the network side receives the location update request that is sent by the UE and carries the user identifier of the UE, so that the UE can reside on the 2G network and the 3G network at the same time; The network side preferentially selects the 2G network for communication; if the 2G network signal does not satisfy the CS domain service requirement, the 3G network is selected for communication. In the embodiment of the present invention, the UE is simultaneously camped on the 2G network and the 3G network, and the network side preferentially selects the 2G network for the CS domain service. Since the information coverage of the 2G network is generally better than that of the 3G network, the priority selection of the 2G network is Improve the communication quality of CS domain services based on voice services, avoid frequent reselection between 2G networks and 3G networks, and improve communication quality; And when the 2G network signal does not meet the requirements, the 3G network can also be used as the backup. When the 3G network is selected for the CS domain service, since the UE has already camped on the 3G network, it is not necessary to initiate the read system message and the location update process, and thus Will increase the turn-on delay.

Further, in consideration of the process of network deployment, some networks support the single-card dual-standby service capability (that is, the network side requirements are met in the embodiment of the present invention), and some networks do not support the single-card dual-standby service capability, and the UE needs to identify the network capability. It only resides in one network when the network does not have the single card dual standby service capability.

In order to enable the UE to identify the network capability, the network side may carry the network capability identifier in the broadcast system message, for example: whether the network supports the single card dual standby service capability on the RNS (Radio Network Subsystem), when the configuration is supported. In the service, the network system supports the single card dual standby capability identifier in the broadcast system message, the UE reads the system message to determine the network capability, and sets the terminal working mode. Only when the 2G/3G system message indicates that the single card dual standby capability is supported. , the single card dual standby function mode is enabled.

Further, in consideration of reducing the impact on the existing ordinary terminal, it is necessary to distinguish between the single card dual standby terminal, the network identification single card dual standby terminal, and only the single card dual standby terminal according to the present invention.

It should be noted that, in the actual network deployment, a VLR (Visitor Location Register) is also needed to store information related to the service. For convenience of description, the embodiments of the present invention do not strictly distinguish between the MSC and the VLR, and the VLR The functions in the embodiments are all incorporated in the MSC, and those skilled in the art can implement the solution in the embodiments of the present invention according to the actual network deployment.

In actual deployment of the network, the MSC may include a 2G MSC for processing 2G services, a 3G MSC for processing 3G services, and a calling MSC for handling calling services. The MSC is divided into functions based on functions. In actual processing, the MSC that performs these functions may be a physical network element (MSC) or multiple physical network elements. For example, the 2G MSC and the 3G MSC are respectively implemented by two physical MSCs, or the 2G MSC and the 3G MSC are completed by one physical MSC, and the physical MSC is a 2G/3G MSC. Similarly, the calling MSC The same physical MSC can also be used with 2G MSC or 3G MSC or 2G/3G MSC. In the following embodiments, for convenience of description, a 2G MSC, a 3G MSC, a calling MSC, and a 2G/3G MSC respectively represent a physical MSC. Those skilled in the art can implement the solution by using the examples given in the embodiments of the present invention and combining actual network deployment situations (using one or more physical MSCs).

The technical solution of the embodiment of the present invention can be generally divided into two phases, the first phase is a location update phase, which is used to complete 2G and 3G location update; the second phase is a CS domain service processing phase (voice call and short message). For the calling MSC or SMC (Short Message Center), after receiving the CS domain service, the 2G MSC or the 3G MSC is selected for CS domain service processing. The technical solutions provided by the embodiments of the present invention will be specifically described below through specific embodiments. Embodiment 3

Based on the foregoing first and second embodiments, the third embodiment of the present invention provides a method for performing location update on a terminal. The network side includes an MSC and an HLR network element device as an example. FIG. 3 is a terminal according to Embodiment 3 of the present invention. A flowchart of a method for performing a location update, see FIG. 3, the method includes:

Step 301: The UE sends a location update request that carries the user identifier of the UE to the MSC. The UE sends a location update request to the MSC when the UE is powered on or when the network location moves. The MSC here refers to the MSC corresponding to the network after the MSC or the UE corresponding to the network in the UE is powered on (for example, moving from the 2G network to the 3G network). It should be noted that sometimes the UE moves only within the network responsible for one MSC (for example, moving from one 2G location area to another 2G location area), then the MSC is the same MSC as the original MSC; When the UE sends the request, it does not need to know the specific MSC, but only needs to send the request in the current network, and the request is received and processed by the MSC corresponding to the network, and the embodiment of the present invention (including other embodiments) Update the request from the UE to the MSC to The expression "the UE sends a location update request to the MSC" is expressed. This expression does not mean that the UE needs to know the MSC to be transmitted by itself and sends a request to the MSC.

The user identifier of the UE is used to identify the UE user, and may be, for example, the IMSI mentioned above.

In addition, the UE may also carry the “terminal capability identifier” in the location update request, that is, it is used to identify whether the UE is a single-card terminal (or a single-card dual-standby terminal) capable of simultaneously camping on two networks in the embodiment of the present invention. If yes, the MSC receives the subsequent process according to the embodiment of the present invention; if not, the MSC follows the normal processing flow in the prior art. By carrying the "terminal capability identifier", the processing on the network side can be better compatible with the terminal in the prior art and the single card dual standby terminal provided in the embodiment of the present invention.

Step 302: After receiving the location update request sent by the UE, the MSC sends a location update request to the HLR, and carries the user identifier, the network identifier, and the MSC identifier in the request.

It should be noted that the location update request sent by the MSC to the HLR and the location update request sent by the UE to the MSC are two different location update requests. For the specific implementation, refer to the description in the standard.

The user identifier is the same as the user identifier in step 301; the network identifier is used to identify the type of the network where the terminal sends the location update request, for example, is a 2G network or a 3G network; where the MSC identifier is used to identify the receiving location update. The requested MSC, for example, when there are multiple MSCs, the MSC is identified as MSC1 or MSC2.

Step 303: The HLR saves location information of the UE according to each identifier in the received location update request.

In order to distinguish the location information saved by the MSC in the subsequent step, the location information here is referred to as "first location information", and the final first location information is: a certain user (determined by the user identity) in a certain network (determined by the network identity) ), corresponding to a certain MSC (determined by the MSC identity). For example, user A is on a 2G network, and the corresponding MSC is MSC1.

It should be noted that when the UE moves to another MSC in the network corresponding to one MSC. The location update request sent by the corresponding network, the HLR also returns an indication of deleting the user data to the original MSC, so that the original MSC deletes the location information of the UE, and the type of the location information to be deleted should be carried in the indication message ( For example, the 2G network) instructs the MSC to delete the corresponding location information.

When the UE sends the location update request to be moved within the network corresponding to the MSC, the MSC directly saves the location information of the UE under the current network identifier after receiving the location update request in step 302 without notifying the HLR. This is because the UE is moving within the MSC. For the pre-mobile and post-mobile, the corresponding MSC of the UE under the current network identifier is the MSC, so there is no need to change the record in the HLR.

Step 304: The HLR sends an "Insert User Data" message to the MSC, where the message carries the network identifier; the network identifier here has the same meaning as the network identifier in step 302;

Step 305: The MSC also saves location information of the UE according to the received message.

The location information here is referred to as "second location information" to distinguish it from the "first location information" in the HLR. The second location information recorded in the MSC is specifically: a certain user is located in a certain location area in a certain network. For example, User A is located in the 2G1 location area in the 2G network, where 2G1 represents a location area of the 2G network, and similarly, 2G2 is used to indicate another location area of the 2G network, and 3G1, 3G2 represent two locations of the 3G network. Area. In the MSC, it is not necessary to record the MSC information as in the HLR, since this information is known to the MSC itself.

In fact, in step S302, the MSC may also record the second location information after receiving the terminal location update request. The embodiment of the present invention does not limit the location information of the MSC and the HLR when the terminal is stored. As long as the location is updated, the location information of the terminal is available in both the MSC and the HLR.

After the step 305, if the network side receives the CS domain service request sent by the calling user, the network that needs to be located after the terminal moves (the location update process is completed by the location update process) is executed to perform the CS domain service. Side based on the saved location information of the updated 2G network The location information of the information and/or 3G network selects the updated network to perform the CS domain service.

In addition, in various embodiments of the present invention, the UE is not limited to sending the location update request after the power on or the location is moved, but sends the location update request when any location update trigger condition (such as periodic location update) is satisfied; The conditions have been defined in detail in the protocol standard and will not be described here. When the UE sends a location update request, the corresponding MSC updates the location information according to the location update request, and the MSC determines whether to update according to whether the UE has moved between the MSCs or whether it is registered with the MSC for the first time. The information in the HLR does not need to update the record in the HLR if the location update of the UE does not result in a change of the MSC corresponding to the UE.

In the embodiments of the present invention, the 2G CS domain core network and the 3G CS domain core network may be deployed separately, that is, the 2G network and the 3G network respectively correspond to one MSC; or may be deployed in a unified manner, that is, the 2G and 3G networks correspond to one MSC. Figure 4A is a schematic diagram of the deployment of the 2G CS domain core network and the 3G CS domain core network, and Figure 4B is a schematic diagram of the 2G CS domain core network and the 3G CS domain core network. The process of the location update process is different according to the situation in which the UE sends the location update request and the deployment of the 2G CS domain core network and the 3G CS domain core network. The location update process shown in Fig. 3 will be described in detail below with reference to Figs. 5A-5E. Embodiment 4

5A is a flowchart of a location update process according to Embodiment 4 of the present invention, and FIG. 5B is a schematic diagram of a terminal residing core network in the embodiment shown in FIG. 5A. In this embodiment, a UE is located in a location area of a 2G network when the UE is powered on. (2G1) and a location area (3G1) located in the 3G network, and the 2G network and the 3G network reside in the 2G and 3G location update processes, as shown in FIG. 5A, specifically including:

Step 501 A: The UE sends a location update request to the MSC1 that carries the 2G network with the UE user identifier.

Step 502A: The MSC1 sends the carrying user identifier, the network identifier, and the MSC to the HLR. The identified location update request;

Because it is a location update of the 2G network, the network identifier is a "2G network" identifier (ie, indicating that the network type is a 2G network); see FIG. 5B, since the MSC corresponding to the 2G network is MSC1, the MSC identifier here is the "MSC1" identifier. (ie indicating that the MSC is MSC1).

After the location update request is sent by the MSC1, the HLR can save the following first location information of the terminal: the terminal user A of the 2G network, and the corresponding MSC is the MSC1;

"User A: 2G Network: MSC1" to indicate. User A is the UE in this embodiment.

The above location information can also be expressed in the manner of Table 1 below for convenience of explanation.

Table 1

In the specific implementation, this part can be temporarily saved, and then saved to the actual storage area after the subsequent steps (such as 504A) are completed. If the subsequent steps fail, the temporarily saved content can be released. In fact, in the embodiment of the present invention, it is only necessary to save the location information after the location update is completed, and it is not limited to which step to save.

Step 503A: The HLR sends an "Insert User Data" message to the MSC1, and carries a network identifier in the message.

Similar to the network identifier in the above step 502A, the network identifier here is also a "2G network" identifier, and is used for the MSC to save the second location information according to the identifier.

Through step 503A, the MSC1 can be caused to save the terminal location information according to the received message.

The second location information of the terminal here is: which location area in which network the terminal is located. As shown in FIG. 5B, the terminal is located in the 2G1 location area in the 2G network. Therefore, the saved information is "end user A is located in the 2G1 location area", and in FIG. 5A, "user A: 2G network: 2G1," Said. The above location information can also be expressed in the manner of Table 2 below for convenience of explanation.

Table 2

As described in the foregoing third embodiment, the step of saving the terminal location information by the MSC1 may also be performed after the step 501A.

Step 504A, MSC1 sends an "Insert User Data Confirmation" message to the HLR.

Step 505A: The HLR sends a "Location Update Confirmation" message to the MSC1.

Step 506A: The MSC1 sends a "Location Update Accept" message to the UE.

The process in the step 503A-step 506A and each message are defined in the standard, and the above-mentioned steps can be implemented by those skilled in the art according to the description in the standard, and details are not described herein again. Through the above steps, the location update of the UE in the 2G network is completed, and the location information of the terminal is saved on the HLR and the MSC.

Similarly, the process of performing location update on the 3G network is similar to the foregoing steps, including: Step 507A: The UE sends a location update request to the MSC1 that carries the 3G network with the UE user identifier.

Step 508A: The MSC1 sends a location update request for the user identifier, the carrying network identifier, and the MSC identifier to the HLR; the network identifier is specifically “3G network”, and the MSC identifier is still “MSC1”; after this step, the location information for the user in the HLR Becomes: "User A: 2G network: MSC1, and 3G network: MSC1".

Step 509A: The HLR sends an "Insert User Data" message to the MSC1, where the message carries the network identifier; the network identifier is specifically "3G network"; after receiving the message, the MSC1 adds a 3G location area to the location information, as shown in Figure 5B. As shown, the 3G location area is 3G1, so the location information of the last terminal in MSC1 is "User A: 2G1 and 3G1".

It should be noted that if other MSCs have old terminal location area information, then It is known that the MSC deletes the old terminal location area information. For example, if the 2G or 3G service is handled by the MSC2 after the update, the old information in the MSC1 needs to be deleted. When the delete message is sent, the network type is also carried, so that the old MSC (such as MSC1) deletes the second location information of the specified network type, for example, the user 2's "2G network: 2G3" location information is deleted.

Step 510A, MSC1 sends an "Insert User Data Confirmation" message to the HLR.

Step 511A: The HLR sends a "Location Update Confirmation" message to the MSC1.

Step 512A: The MSC1 sends a "Location Update Accept" message to the UE.

Through the above process, the location area update of the terminal in the 2G network and the 3G network can be completed, where step 501 A-step 506A is the location update initiated by the UE in the 2G1 location area of the 2G network MSC1, and steps 507A-512A are the UE The location update initiated by the 3G1 location area of the 3G network MSC1, the flow of the two location updates is similar. In addition, this embodiment does not limit the order of 2G and 3G network update, that is, the steps may be performed first.

507A-512A, then perform steps 501A-506A. Embodiment 5

The fifth embodiment of the present invention provides another location update process. The application scenario of the location update process is as follows: The two networks where the CS domain is located after the UE is powered on (that is, the 2G network and the 3G network that need to reside) correspond to one MSC, respectively. For example, here are 4 settings:

The 2G network corresponds to MSC1;

The 3G network corresponds to MSC2;

For this scenario, the terminal sends a location update request to MSC1 (corresponding to 2G location update) and MSC2 (corresponding to 3G location update) when performing 2G or 3G location update; MSC 1, MSC2, and HLR processing methods can be implemented. The steps in the fourth example will not be described here.

Finally, the user location information stored in the HLR is: "User A: 2G network: MSC1, and 3G network: MSC2"; User location information stored in MSC1 and MSC2 is Corresponding to a certain location area in a certain network (equivalent to splitting the location information in the MSC in Embodiment 3 into two, which are respectively saved by the two MSCs).

In the embodiment of the present invention, when the HLR sends the user data message or deletes the user data message to the MSC1 or the MSC2, the network identifier may not be carried, because each MSC only corresponds to one network, and the MSC does not need to distinguish the 2G network or the 3G network. Network, so there is no need to carry a network identity. Similarly, there is no need to store information of the network type in the second location information. Embodiment 6

FIG. 5C is a flowchart of a location update process according to Embodiment 6 of the present invention, and FIG. 5D is a schematic diagram of location update in the embodiment shown in FIG. 5C.

Core network integration deployment (2G, 3G network corresponds to the same MSC), as shown in Figure 5D, MSC1 corresponds to both 2G network (location area 2G1 and 2G2) and 3G network (location area 3G1 and 3G2); MSC2 Corresponds to 2G networks (such as 2G3, 2G4) and 3G networks (such as 3G3, 3G4). The UE is initially located in the network (2G2, 3G2) corresponding to the MSC1, and then moved to the network (2G3, 3G3) corresponding to the MSC2.

As shown in FIG. 5C, the location update process of the embodiment of the present invention includes:

Step 501C: The UE sends a location update request to the MSC2 that carries the 3G network with the UE user identifier.

As shown in FIG. 5C, the UE moves, and the UE's 3G network location moves from the 3G2 location area of the MSC1 to the 3G3 location area of the MSC2, and the UE performs the operation of step 501C.

Step 502C: After receiving the location update initiated by the UE, the MSC2 queries the MSC2 to have no 3G location record of the user, and sends a location update request carrying the user identifier, the 3G network identifier, and the MSC2 identifier to the HLR.

Because it is a location update of the 3G network, the network identifier is a "3G network" identifier (ie, indicating that the network type is a 3G network); see FIG. 5D, since the corresponding MSC is the MSC2 after the 3G network moves, the MSC identifier here is "MSC2". "Identification (ie indicating that the MSC is MSC2). After the location update request is sent by the MSC2, the HLR can save the following first location information of the terminal: that is, the terminal user A of the 3G network, and the corresponding MSC is the MSC2;

"User A: 3G Network: MSC2" to indicate. User A is the UE in this embodiment.

The above location information can also be expressed in the manner of Table 3 below for convenience of explanation.

table 3

Step 503C: The HLR sends an "Insert User Data" message to the MSC2, where the message carries the network identifier. Like the network identifier in the foregoing step 502C, the network identifier here is also the "3G network" identifier.

In step 503C, the MSC2 may be configured to save the second location information of the terminal according to the received message; where the second location information is: which location in the network the terminal is located. As shown in FIG. 5D, after the terminal moves, it is located in the 3G3 location area of the 3G network. Therefore, the saved information is "end user A is located in the 3G3 location area of the 3G network", and is represented by "user A: 3G network: 3G3" in FIG. 5C. . The above location information can also be expressed in the manner of Table 4 below for convenience of explanation.

Table 4

As described in the foregoing third embodiment, the step of saving the terminal location information by the MSC2 may also be performed after the step 501C.

Step 504C: The MSC2 sends an "Insert User Data Confirmation" message to the HLR. Step 505C: After receiving the "Insert User Data Confirmation" message returned by the MSC2, the HLR sends a "Delete User Data" message carrying the 3G network identifier to the MSC1.

The UE moves from MSC1 to MSC2, thereby deleting the location information of the UE originally existing in MSC1. When the message is sent, the network type is also carried, so that the old MSC (MSC1) deletes the second location information of the specified network type.

Step 505C may not be performed until after execution of 503C, 504C, but may be performed in parallel with 503C.

Step 506C: The MSCl receives the delete user data message, deletes the user 3G location record location information in the MSC1 according to the 3G network identifier in the message, and returns a user data deletion confirmation message to the HLR.

Step 507C: After receiving the MSC deletion user data confirmation message, the HLR sends a "Location Update Confirmation" message to the MSC2.

Step 508C: The MSC2 sends a "Location Update Accept" message to the UE.

Through the above steps, the location update of the UE in the 3G network is completed, and the location information of the terminal is saved on the HLR and the MSC.

Similarly, the process of performing location update on the 2G network is similar to the foregoing steps, including: Step 509C: The UE sends a location update request to the MSC2 that carries the 2G network with the UE user identifier.

As shown in FIG. 5D, the UE moves, and the 2G network location of the UE is updated from the 2G2 location area of the MSC1 to the 2G3 location area of the MSC2, and the UE performs the operation of step 509C.

It should be noted that, in this embodiment, the 3G network location and the 2G network location of the UE are both moved from the MSC1 to the MSC2. However, the embodiment is not limited thereto. For example, the 3G network location of the UE may be moved from the MSC 1 to the MSC2. The 2G network location can be moved from MSC3 to MSC4.

Step 510C: The MSC2 sends a location update request for the user identifier, the network identifier, and the MSC identity to the HLR. The network identifier is specifically a "2G network" and the MSC identifier is "MSC2". After the step, the location information for the user in the HLR changes. For: "User A: 2G Network: MSC2, and 3G network: MSC2".

Step 511C: The HLR sends an "Insert User Data" message to the MSC2, where the message carries the network identifier; the network identifier is specifically "2G network"; after receiving the message, the MSC2 adds a 2G location area in the location information, as shown in Figure 5D. As shown, the 2G location area is 2G3, so the second location information of the last terminal in MSC2 is "User A: 2G Network: 2G3 and 3G Network: 3G3".

Step 512C, MSC2 sends an "Insert User Data Confirmation" message to the HLR.

Step 513 C: The HLR sends the deleted user data carrying the 2G network identifier to the MSCl.

Step 514C: The MSCl receives the delete user data message, deletes the user 2G location record in the MSC1 according to the 2G network identifier in the message, and returns a user data deletion confirmation message to the HLR.

Step 515C: The HLR sends a "Location Update Confirmation" message to the MSC2.

Step 516C: The MSC2 sends a "Location Update Accept" message to the UE.

Through the above process, the location area update of the terminal on the 2G network and the 3G network can be completed. Step 501C-step 508C is a location update of the UE in the 3G network, and step 509C-step 516C is a location update of the UE in the 2G network, and the processes of the two location updates are similar. Furthermore, this embodiment does not limit the order of 2G and 3G network updates.

The embodiment shown in FIG. 5C and FIG. 5D is a scenario in which the 2G and the 3G reside in the same core network. In this embodiment, the location movement of the UE is not limited thereto, and may also be applied to the different cores where the 2G and the 3G reside in different cores. The scene of the net. Example 7

The seventh embodiment of the present invention provides another location update process. The application scenario of the location update process is as follows: The two networks in which the UE's CS domain resides correspond to the same MSC UE moving in the same MSC. FIG. 5E is a more detailed location in the location update process according to Embodiment 7 of the present invention; New schematic. As shown in FIG. 5E, the 2G network location of the UE is updated from the 2G1 location area to the 2G2 location area, and the 2G network location of the UE is updated from the 3G1 location area to the 3G2 location area; where 2G1 and 2G2 belong to the same MSC, and 3G1 and 3G2 belong to the same One MSC. In this embodiment, the MSC to which the 2G network location belongs and the MSC to which the 3G network location belongs may be the same or may not be the same. FIG. 5E shows the case where the 2G and 3G network locations belong to the same MSC. In this embodiment, the UE initiates the 2G network location update and the 3G network location update respectively, and the MSC determines that the location update belongs to the intra-office location update, and the MSC updates the two location information records stored in the VLR without notifying the HLR. Finally, the user location information saved in the MCS is "User A: 2G Network: 2G2 and 3G Network: 3G2".

Through the location update procedure in the embodiment shown in Figures 5A-5E, the UE can reside in both the 2G network and the 3G network in the CS domain.

Through the foregoing location update embodiment, the dual CS of the terminal CS domain in the two networks can be implemented. The processing flow when the network side performs voice and short message services will be specifically described below. Example eight

In the embodiment of the present invention, when the network side receives the call request (voice service) of the user, the network side preferentially selects the 2G network for the CS domain service processing according to the saved terminal location information (stored in the MSC and the HLR respectively).

FIG. 6 is a flowchart of processing a voice called service on the network side according to Embodiment 8 of the present invention. As shown in FIG. 6, the process includes:

Step 601: The HLR receives the routing request sent by the calling MSC according to the voice request of the calling user, and requests routing information from the MSC (hereinafter referred to as 2G MSC) corresponding to the 2G network where the called UE camps; wherein, the calling MSC is mainly Call the MSC corresponding to the user.

Step 602: The HLR obtains routing information corresponding to the called UE from the 2G MSC, and sends the obtained routing information to the calling MSC, so that the calling MSC can preferentially communicate through the 2G network. The 2G and 3G core networks may be deployed separately or in combination. The voice service flow shown in FIG. 6 is described in detail below through the specific embodiments shown in FIG. 7A to FIG. 7C. Example nine

FIG. 7A is a flowchart of a voice called flow according to Embodiment 9 of the present invention. The application scenario of this embodiment is: 2G and 3G core networks are deployed separately. In this embodiment, since the 2G and 3G core networks are deployed separately, the MSCs corresponding to the 2G and 3G networks are different; therefore, the HLR selects to use the 2G network, and after the HLR obtains the MSC2 corresponding to the 2G, the UE can be directly obtained from the MSC2. Routing information, the routing information is 2G routing information; the HLR sends the routing information to the calling MSC; the HLR sends the obtained routing information to the calling MSC, and then the calling MSC routes to the MSC2, MSC2 according to the routing information. The paging is sent, so that the voice service passes through the 2G network. Specifically, as shown in FIG. 7A, the process may include:

Step 701A: The calling MSC receives the incoming call request and requests routing information from the HLR. When the calling user wants to conduct a call service with the called user, it first sends a request to the calling MSC, and after receiving the request, the calling MSC requests routing information from the HLR.

Step 702A: The HLR queries the user location information (first location information). It is assumed that the 2G network of the called user corresponds to the MSC2, and the 3G network corresponds to the MSC4. The HLR preferentially obtains the route to the 2G MSC (MSC2) according to the configured service selection policy. Information, where the routing information is represented by a roaming number, therefore, obtaining routing information from the MSC 2 is accomplished by requesting the MSC 2 to provide the roaming number of the called user.

The foregoing HLR preferentially obtains routing information from the 2G MSC, that is, the location information corresponding to the 2G network is saved in the user location information in the HLR (for example, user A: 2G network: MSC2); if not, the routing information is obtained from the 3G MSC. The premise is that the location information corresponding to the 3G network is stored in the user location information in the HLR.

Step 703A: The MSC2 queries the location information of the called user, and returns the roaming number corresponding to the called user to the HLR. Since the 2G and 3G core networks are deployed separately, there is only one location information (second location information) of the called user in the MSC2.

Step 704A: The HLR returns the routing information of the called user to the calling MSC.

After receiving the roaming number of the called user, the HLR sends the routing information indicated by the roaming number to the calling MSC.

Step 705A: The calling MSC sends a page according to the routing information to perform call connection. The calling MSC routes to the MSC2 according to the routing information, and the MSC2 sends a page.

In this embodiment, if the paging fails through the 2G MSC, the terminal can re-acquire the 3G routing information to the HLR when the terminal has the capability of simultaneously camping on the two networks, and the HLR obtains the 3G routing information and the HLR obtains the 2G routing information. The process is similar, but the network type needs to be identified. Then the HLR sends the acquired 3G routing information to the 2G MSC. The 2G MSC connects the call to the 3G MSC according to the 3G routing information, and the 3G MSC pages the called party from the 3G network. User, and establish a call in the 3G network.

In addition, if the HLR queries the 3G MSC for the routing information in step 702A, the subsequent 3G MSC processing mode is similar to that of the 2G MSC processing, and will not be described in detail herein. Finally, the calling MSC sends a paging through the 3G MSC. Example ten

FIG. 7B is a flowchart of a voice called flow according to Embodiment 10 of the present invention. The application scenario of this embodiment is: 2G and 3G core network are deployed in a unified manner, and the MSC selects to use the 2G network, that is, configures the network in the MSC. In this embodiment, the HLR sends a roaming number request to the MSC2, and the MSC2 returns the roaming number information to the HLR. The HLR sends the routing information corresponding to the roaming number information to the calling MSC, and then the calling MSC sends the voice according to the routing information. The call is routed to the MSC2, and the MSC2 selects the 2G network to send the page. Specifically, as shown in FIG. 7B, the process may include:

Step 701B: The calling MSC receives the incoming call request and requests routing information from the HLR. Step 702B: The HLR queries the user location information, and the 2G location and the 3G location of the called user all correspond to the same MSC (for example, MSC1), and the HLR sends a request for providing a roaming number to the MSC1.

Step 703B: The MSC1 allocates the user roaming number and returns it to the HLR.

Step 704B: The HLR returns the routing information (represented by the roaming number) of the called user to the calling MSC.

Step 705B: The calling MSC routes to the corresponding MSC1 according to the routing information, and performs call connection.

Step 706B: The MSC1 sends a paging to the UE in the 2G network according to the configured network selection policy. Similarly, in this embodiment, if the paging fails through the 2G routing information, after determining that the terminal has the capability of simultaneously camping on the two networks, it can re-acquire 3G routing information to the HLR and establish a call in the 3G network. Embodiment 11

7C is a flowchart of a voice called flow according to Embodiment 11 of the present invention. The application scenario of this embodiment is: 2G and 3G core network are deployed in a unified manner, and the HLR selects to use the 2G network, that is, configures the network in the HLR. In this embodiment, the MSC needs to be able to allocate a 2G or 3G roaming number according to the network identifier, and send a page according to the different network identifier of the roaming number in the corresponding network identifier; the HLR sends the provided roaming number carrying the 2G network identifier to the MSC2. Requesting, then MSC2 returns to the HLR the roaming number information for the 2G network corresponding to the UE, and the HLR sends the routing information corresponding to the roaming number information to the calling MSC; then the calling MSC routes to the MSC2 according to the routing information, and the MSC2 according to the routing information The 2G roaming number is sent to the paging, so that the voice service is carried over the 2G network. Specifically, as shown in FIG. 7C, the process includes:

Step 701C: The calling MSC receives the incoming call request and requests routing information from the HLR. Step 702: The HLR queries the user location information, and the 2G location and the 3G location of the called user correspond to the same MSC (for example, MSC1). The HLR sends the request for providing the roaming number carrying the 2G network identifier to the MSC1 according to the configured service selection policy. , which carries 2G The network identifier is used to notify the MSC1 to return the 2G roaming number. If the 3G roaming number needs to be returned, the 3G network identifier is carried.

Step 703C: The MSC1 allocates a 2G roaming number according to the request for providing a roaming number of the 2G identifier sent by the HLR, and returns the RN to the HLR.

Step 704C: The HLR returns the 2G routing information corresponding to the 2G roaming number of the called user to the calling MSC.

Step 705C: The calling MSC sends a call connection to the MSC1 that returns the routing information, so that the MSC1 initiates a call to the terminal according to the saved location information and routing information.

Here, the routing information is represented by a roaming number, and the roaming number returned by the MSC1 can be further divided into a 2G roaming number and a 3G roaming number. The MSC1 can select a 2G network or a 3G network for voice service by using the routing information represented by the 2G roaming number or the 3G roaming number and the saved location information (second location information).

Similarly, in this embodiment, if the paging fails through the 2G routing information, the call can be established in the 3G network after determining that the terminal has the capability of simultaneously camping on the two networks. Example twelve

FIG. 8 is a flowchart of receiving a short message service according to Embodiment 12 of the present invention. As shown in FIG. 8, the process of receiving a short message service includes:

Step 801: The HLR receives the routing request sent by the SMC according to the short message request of the calling user, and queries the MSC2 corresponding to the UE for the 2G network. The SMC is an SMC that sends a short message request to the called user.

This embodiment is a service flow when the UE receives a short message, and the UE stays in the 2G and 3G networks simultaneously in the CS domain. For the short message service, the network side preferentially selects the 2G network for communication according to the configured network selection policy.

The calling user sends a short message, and the SMC sends a short message routing request to the HLR according to the short message request, where the short message routing request carries the user identifier of the UE as the called party; After receiving the short message routing request, the MSC corresponding to the UE for the 2G network (ie, the MSC2) is queried.

According to the foregoing FIG. 4A and FIG. 4B, the 2G CS domain core network and the 3G CS domain core network may be deployed separately or in combination. When the 2G CS domain core network and the 3G CS domain core network are deployed separately, the MSC for the 2G network is different from the MSC for the 3G network; when the 2G CS domain core network and the 3G CS domain core network are deployed in one, The MSCs for 2G networks and 3G networks are the same.

Step 802: The HLR sends the identifier of the MSC2 to the SMC to communicate through the 2G network.

After the HLR queries the MSC2, it sends the identifier of the MSC2 to the SMC.

The receiving short message service flow shown in FIG. 8 is described in detail below through FIG. 9A to FIG. 9C. Example thirteen

FIG. 9A is a flowchart of a process for receiving a short message service according to Embodiment 13 of the present invention. The application scenario of this embodiment is: 2G and 3G core networks are deployed separately, and the MSC corresponding to the 2G and 3G networks is different; therefore, the HLR selects After the 2G network is used, the HLR obtains the MSC2 corresponding to the 2G, and then directly sends the identifier of the MSC2 to the SMC, and then the SMC can send the short message through the MSC2. Specifically, as shown in FIG. 9A, the process includes:

Step 901A: After receiving the short message sent by the calling user, the SMC requests the HLR to be routed by the SMC to the called user.

Step 902A: The HLR queries the user location information, where the 2G location of the called user corresponds to the MSC2, and the 3G location corresponds to the MSC4. The HLR preferentially selects the MSC2 corresponding to the 2G according to the configured service selection network policy, and returns the identifier of the MSC2 to the SMC.

Step 903 A. The SMC sends a short message to the MSC2.

The UE supports receiving short messages from a 2G network or a 3G network. Embodiment 14

FIG. 9B is a flowchart of a process for receiving a short message service according to Embodiment 14 of the present invention. In this embodiment, a 2G and a 3G core network are deployed in combination, and the MSC selects to use a 2G network, that is, configures a network selection policy in the MSC; In this embodiment, the HLR returns the identifier of the MSC2 to the SMC, and the SMC sends a short message to the MSC2. After receiving the short message, the MSC2 selects the 2G network to deliver the short message according to the configured network selection policy. Specifically, as shown in FIG. 9B Show that the process includes:

Step 901B: After receiving the short message sent by the calling user, the SMC requests the HLR to be routed by the SMC to the called user.

Step 902B: The HLR queries the user location information, and the 2G location and the 3G location of the called user all correspond to the same MSC (for example, MSC1), and the HLR sends the identifier of the MSC1 to the SMC.

Step 903B: The SMC sends a short message to the MSC1. After receiving the short message, the MSC1 queries the user location information. The user has both the 2G location information and the 3G location information. The MSC1 preferentially sends the short message from the 2G network according to the configured service selection policy. Message.

The UE supports receiving short messages from a 2G network or a 3G network. Example fifteen

9C is a flowchart of a process for receiving a short message service according to Embodiment 15 of the present invention. In this embodiment, a 2G and a 3G core network are deployed in a unified manner, and the HLR selects to use a 2G network, that is, a network selection policy is configured in the HLR; In an embodiment, when the HLR returns the identifier of the MSC2 to the SMC, the HMC sends a 2G network identifier to the SMC, so that the SMC can carry the 2G network identifier when sending the short message to the MSC2, and then the MSC2 selects to use the 2G network to send the short according to the 2G network identifier. Specifically, as shown in FIG. 9C, the process includes:

Step 901C: After receiving the short message sent by the calling user, the SMC requests the HLR to be routed by the SMC to the called user.

Step 902C: The HLR queries the user location information, the 2G location and the 3G location of the called user. Both correspond to the same MSC (for example, MSC1), and the HLR will

The identity of the MSC1 and the 2G network identity are sent to the SMC.

Step 903: The SMC sends a short message carrying the 2G network identifier to the MSC1.

Step 904C: After receiving the short message, the MSC1 sends the 2G network identifier to query the location information of the user on the 2G network, and sends a short message from the 2G network. Example sixteen

Based on the foregoing embodiment, the embodiment of the present invention provides a terminal, and FIG. 10 is a schematic diagram of a terminal according to Embodiment 16 of the present invention; as shown in FIG. 10, the terminal is a single SIM card terminal, and the SIM card includes a user identifier. The terminal specifically includes:

The 2G processing module 1001 is configured to send, to the network side, a 2G network location update request that carries the user identifier, so that after receiving the 2G network location update request, the network side completes the circuit switched CS domain location with the terminal. Updating the process such that the CS domain of the terminal resides on the 2G network;

The 3G processing module 1002 is configured to send, to the network side, a 3G network location update request that carries the user identifier, so that after receiving the 3G network location update request, the network side completes the circuit switched CS domain location together with the terminal. Updating the process such that the CS domain of the terminal resides on the 3G network;

The selecting module 1003 is configured to: when the CS domain service request is initiated, preferentially select the 2G network to perform the CS domain service by using the 2G processing module, and when the 2G network does not meet the CS domain service requirement, pass the The 3G processing module selects the 3G network to perform the CS domain service.

The 2G processing module is mainly used to process services related to 2G networks. The 3G processing module is mainly used to process services related to 3G networks. The two modules are functionally independent modules, each running a 2G protocol stack and a 3G protocol stack. When implemented in hardware, both modules can be implemented with the same processing chip (there are two separate functional modules, for example two processing based on hardware) Modules, enclosed in a processing chip), or implemented separately with a hardware processing chip.

For the working process and working principle of each module in this embodiment, refer to the detailed description in the foregoing method embodiments, and details are not described herein again.

In the embodiment of the present invention, the UE camps on the 2G network and the 3G network at the same time, and the 2G network is preferentially selected for the CS domain service. Since the coverage of the 2G network is generally better than that of the 3G network, the priority selection of the 2G network can improve the voice service. The communication quality of the main CS domain service avoids frequent reselection between the 2G network and the 3G network, improves the communication quality; and when the 2G network signal does not meet the requirements, the 3G network can also be used as the backup, and the 3G network is selected. When the CS domain service is performed, the UE already camps on the 3G network, so there is no need to initiate a location update procedure, and the connection delay is not increased. Example seventeen

11 is a schematic structural diagram of an MSC according to Embodiment 17 of the present invention. As shown in FIG. 11, the MSC is a 2G/3G MSC that is used for both a 2G network and a 3G network, and the MSC includes: a receiving module 1101, and a sending The module 1103, the route returning module 1105, and the call selection module 1107; the receiving module 1101 is configured to receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single SIM card, the SIM card includes a user identifier, and the 2G network location The update request and the 3G network location update request carry the same user identifier; and the circuit switched CS domain of the terminal resides on the 2G network and the 3G network, and saves the location information of the resident 2G network and the location information of the 3G network;

The sending module 1103 is configured to send a first network location update request and a second network location update request to the HLR, where the first network location update request carries the user identifier, the 2G network identifier, and the 2G/3G MSC identifier, and the second network location update The request carries a user identifier, a 3G network identifier, and a 2G/3G MSC identifier;

The 2G network identifier and the 3G network identifier are used to identify the network type of the network where the terminal sends the location update request, and the 2G/3G MSC identifier is used for the identifier connection. Receiving the MSC of the location update request;

And sending, by the first network location update request and the second network location update request, the HLR to save the first location information according to the received first network location update request and the second network location update, where the first location information The network type of the network where the terminal sends the location update request and the identifier of the MSC that receives the location update request;

The receiving module 1101 is further configured to: receive an insertion user data notification sent by the HLR after receiving the first network location update request and the second network location update request, where the notification carries the network type of the network where the terminal sends the location update request, and receives the network type Saving the second location information after the notification, where the second location information includes the network type and the location area information of the network where the terminal sends the location update request;

The receiving module 1101 is further configured to: receive a request for acquiring routing information sent by the HLR, where the HLR sends a request for obtaining routing information when the calling MSC queries the routing information request, where the calling MSC sends the receiving caller. When requesting a CS domain service, sending a request for querying routing information to the HLR;

The route returning module 1105 is configured to return routing information to the HLR according to the request of the HLR, so that the HLR returns the routing information of the terminal to the calling MSC;

The call selection module 1107 is configured to receive a call connection sent by the calling MSC according to the routing information, and preferentially initiate a call to the terminal through the 2G network according to the saved second location information, and when the 2G network does not meet the CS domain service requirement, according to the saved The two location information initiates a call to the terminal through 3G.

For the working process and working principle of each module in this embodiment, refer to the detailed description in the foregoing method embodiments, and details are not described herein again. In the specific hardware implementation, it can be implemented based on the hardware architecture of the existing MSC. For example, the code can be updated in the chip to implement the corresponding functional module.

The MSC provided by the embodiment of the present invention can be used together with the UE and other network side devices to enable the UE to residing on the 2G network and the 3G network at the same time, and to preferentially select the 2G network for the CS domain service to communicate, thereby avoiding the 2G network and the 3G network. Frequent re-election, improving communication quality Amount; and when the 2G network signal does not meet the requirements, the 3G network can also be used as a backup. Example 18

FIG. 12 is a schematic structural diagram of an HLR according to Embodiment 18 of the present invention. As shown in FIG. 12, the HLR includes: a location update receiving module 1201, a saving module 1203, and a route obtaining module 1205.

The location update receiving module 1201 is configured to receive a first network location update request and a second network location update request respectively sent by the 2G mobile switching center MSC and the 3G MSC, where the first network location update request carries a user identifier, a 2G network identifier, and The 2G MSC identity, the second network location update request carries a user identity, a 3G network identity, and a 3G MSC identity.

The 2G network identifier and the 3G network identifier are used to identify a type of a network where the terminal corresponding to the user identifier sends a location update request, where the 2G MSC identifier and the 3G MSC identifier are used to identify a receiving location update. Requested MSC.

The saving module 1203 is configured to save the first location information according to the received first network location update request and the second network location update request, where the first location information includes a network where the terminal sends the location update request a network type and an identifier of the MSC that receives the location update request; and notifying the 2G MSC and the 3G MSC to insert user data, so that the 2G MSC and the 3G MSC save the second location information after receiving the notification, where the The second location information includes location area information of the network where the terminal sends the location update request; if another MSC stores the old second location information, the other MSC is notified to delete the old second location information. The first location information in the embodiments of the present invention may simultaneously include an identifier of an MSC corresponding to the end user in the 2G network and the 3G network.

The route obtaining module 1205 is configured to receive a request for querying routing information of the terminal sent by the calling MSC, and obtain routing information for the 2G network according to the saved first location information; When there is no location information corresponding to the 2G network in a location information or the 2G network does not satisfy the CS domain service requirement, the 3G MSC is acquired for the 3G network. Routing information; The calling MSC sends a request for querying routing information to the HLR when receiving a CS domain service request sent by the calling user.

The route obtaining module 1205 is further configured to: return, to the calling MSC, a routing information of the terminal.

In the HLR provided in this embodiment, the terminal is simultaneously saved in the 2G network.

The identifier of the MSC and the identifier of the MSC corresponding to the 3G network enable the HLR to preferentially select the 2G network for the CS domain service.

The 2G MSC and the 3G MSC in this embodiment may be one physical network element (MSC) or multiple physical network elements. For example, the 2G MSC and the 3G MSC are respectively implemented by two physical MSCs, or the 2G MSC and the 3G MSC are completed by one physical MSC, and the physical MSC is a 2G/3G MSC. Similarly, the calling MSC can also use the same physical MSC as the 2G MSC or 3G MSC or 2G/3G MSC.

It should be noted that when the 2G MSC and the 3G MSC are completed by one physical MSC (2G/3G MSC), when receiving the CS domain service request sent by the calling MSC, the route obtaining module 1205 in the HLR may preferentially forward to the 2G. The /3G MSC obtains the routing information for the 2G network. Alternatively, the route obtaining module 1205 may be replaced by another route obtaining module A. When the route obtaining module A obtains routing information from the 2G/3G MSC, the routing information is not limited to 2G. The routing information of the network, but only the routing information corresponding to the 2G/3G MSC is sent to the calling MSC. When the calling MSC calls the 2G/3G MSC, the 2G/3G MSC preferentially delivers the CS domain service through the 2G network.

The HLR provided by the embodiment of the present invention can be used together with the UE and other network side devices to enable the UE to residing on the 2G network and the 3G network at the same time, and to preferentially select the 2G network for the CS domain service to communicate, thereby avoiding the 2G network and the 3G network. Frequent re-election between them improves the communication quality; and when the 2G network signal does not meet the requirements, the 3G network can also be used as a backup. Example 19

The embodiment of the invention provides a communication system, including:

The 2G MSC is configured to receive a 2G network location update request sent by the terminal; the terminal is a single user identity module SIM card, the SIM card includes a user identifier, and the 2G network location update request carries the user identifier Sending a first network location update request to the HLR, where the first network location update request carries the user identifier, a 2G network identifier, and a 2G MSC identifier;

The HLR is configured to save first location information according to the received first network location update request and the second network location update request, where the first location information includes a network where the terminal sends a location update request The network type and the identifier of the MSC that receives the location update request; and the 2G MSC and the 3G MSC are notified to insert the user data, and the network type is carried in the notification, so that the 2G MSC and the 3G MSC receive the notification. Saving the second location information, where the second location information includes the network type and the location area information of the network where the terminal sends the location update request; if other MSCs store the old second location information, notify the other MSC to delete the old location information. Second location information;

The calling MSC is configured to receive a CS domain service request sent by the calling user, to the The HLR queries the routing information of the terminal;

The HLR is further configured to: preferentially obtain routing information from the 2G MSC according to the saved first location information; and acquire a route to the 3G MSC when the location information corresponding to the 2G network does not exist in the first location information. Information

The 2G MSC or the 3G MSC is further configured to: return the routing information to the HLR according to the saved second location information, so that the HLR returns the routing information of the terminal to the calling MSC;

The calling MSC is further configured to initiate a call to the terminal to the 2G MSC that returns routing information or the 3G second location information. Example twenty

The embodiment of the invention provides a communication system, including:

The HLR is configured to: according to the received first network location update request and the first And the first location information includes a network type of the network where the terminal sends the location update request and an identifier of the MSC that receives the location update request, and notifies the 2G/3G MSC to insert the user. Data, the network type is carried in the notification, so that the 2G/3G MSC saves the second location information after receiving the notification, where the second location information includes the network type and a location area of the network where the terminal sends the location update request information;

The HLR is further configured to: obtain, according to the saved first location information, routing information to the 2G/3G MSC;

The 2G/3G MSC is further configured to: return routing information to the HLR, so that the HLR returns routing information of the terminal to the calling MSC;

The calling MSC is further configured to send a call connection to the 2G/3G MSC that returns routing information, and the 2G/3G MSC preferentially initiates a call to the terminal through the 2G network according to the saved second location information. When the 2G network location information does not exist in the second location information, or the 2G network does not meet the CS domain service requirement, the 2G/3G MSC initiates a call to the terminal through the 3G network according to the saved second location information. Embodiment 21

The embodiment of the invention provides a communication system, including:

The 2G/3G MSC is configured to receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single user identity module SIM card, the SIM card includes a user identifier, and the 2G network location And the update request and the 3G network location update request carry the same user identifier; send a first network location update request and a second network location update request to the HLR, where the first network location update request carries the User standard The second network location update request carries the user identifier, the 3G network identifier, and the 2G/3G MSC identifier, and the 2G/3G MSC identifier;

The HLR is configured to: save the first location information according to the received first network location update request and the second network location update, where the first location information includes a network where the terminal sends a location update request And the network type and the identifier of the MSC that receives the location update request; and notifying the 2G/3G MSC to insert the user data, and the network type of the terminal is accessed when the notification is sent, so that the 2G/3G MSC saves the second location information after receiving the notification. The second location information includes the network type and the location area information of the network where the terminal sends the location update request. The calling MSC is configured to receive the CS domain service request sent by the calling user, and query the HLR. Routing information of the terminal;

For the specific interaction of the network elements in the communication system in the foregoing three embodiments, and the beneficial effects of the communication system, refer to the description in the method embodiment, and details are not described herein.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting thereof; although the present invention has been described in detail with reference to the foregoing embodiments, It should be understood that: the technical solutions described in the foregoing embodiments may be modified, or some of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the essence of the corresponding technical solutions. The spirit and scope of the technical programme.

Claims

A single-card dual-standby terminal circuit-switching method in which a cs-domain resides in a network at the same time, and is characterized in that it is applied to a SIM card terminal of a single-user identity module, and the SIM card includes a user identifier, and the method includes:

When the CS domain service is initiated, the 2G network is preferentially selected to perform the CS domain service. When the 2G network does not meet the CS domain service requirement, the 3G network is selected to perform the CS domain service.

2. A single-card dual-standby terminal circuit switching method in which a CS domain simultaneously resides on two networks, and is characterized in that it is applied to a network side, including:

3. The method of claim 2, wherein:

The location information of the 2G network and the location information of the 3G network include first location information and second location information; The first location information includes a network type and an MSC identifier stored in the location home register HLR, where the network type is a type of the network in which the terminal sends the location update request, and the MSC identifier is an identifier of the MSC that receives the location update request.

The second location information includes the network type and location area information stored in the mobile switching center MSC, where the location area information is a location area in a network where the terminal sends a location update request.

4. The method according to claim 2, further comprising:

Receiving, by the terminal, a network location update request that carries the user identifier, and completing a CS domain location update procedure with the terminal, so that the CS domain of the terminal resides. To the updated network; simultaneously update the location information of the saved 2G network and/or the location information of the 3G network;

When receiving the CS domain service request sent by the calling user, the updated network is selected to execute the CS domain service according to the saved updated location information of the 2G network and/or the location information of the 3G network.

5. A communication system, comprising:

The 3G MSC is configured to receive a 3G network location update request sent by the terminal; the 3G network location update request also carries the user identifier; and send a second network location update request to the HLR, where the second The network location update request carries the user identifier, the 3G network identifier, and the 3G MSC identifier; The 2G network identifier and the 3G network identifier are used to identify the type of the network where the terminal sends the location update request, and the 2G MSC identifier and the 3G MSC identifier are used to identify the MSC that receives the location update request.

The HLR is configured to save first location information according to the received first network location update request and the second network location update request, where the first location information includes a network where the terminal sends a location update request The network type and the identifier of the MSC that receives the location update request, and notifies the 2G MSC and the 3G MSC to insert user data, so that the 2G MSC and the 3G MSC save the second location information after receiving the notification, The second location information includes location area information of the network where the terminal sends the location update request; if other MSCs store the old second location information, notify other MSCs to delete the old second location information; the calling MSC is used by Receiving a CS domain service request sent by the calling user, and querying, by the HLR, routing information of the terminal;

The HLR is further configured to: preferentially obtain routing information from the 2G MSC according to the saved first location information; when there is no location information corresponding to the 2G network in the first location information, or the 2G network is not satisfied When the CS domain service requires, the routing information is obtained from the 3G MSC; the 2G MSC or the 3G MSC is further configured to: return the routing information to the HLR according to the saved second location information, so that the HLR Returning routing information of the terminal to the calling MSC;

The calling MSC is further configured to initiate a call to the terminal to the 2G MSC that returns routing information or the 3G second location information.

6. A communication system, comprising:

The 2G/3G MSC is configured to receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single user identity module SIM card, where the SIM card is Having a user identifier, the 2G network location update request and the 3G network location update request carrying the same user identifier; sending a first network location update request and a second network location update request to the HLR, where The network location update request carries the user identifier, the 2G network identifier, and the 2G/3G MSC identifier, where the second network location update request carries the user identifier, the 3G network identifier, and the 2G/3G MSC identifier.

The calling MSC is configured to receive a CS domain service request sent by the calling user, to the

The HLR queries the routing information of the terminal;

7. A communication system, comprising: 2G/3G mobile switching center MSC, location home register HLR, and calling mobile switching center MSC;

The 2G/3G MSC is further configured to: return, to the HLR, routing information of a specified network type, so that the HLR returns routing information of the terminal to the calling MSC; The calling MSC is further configured to send a call connection to the 2G/3G MSC that returns routing information, so that the 2G/3G MSC initiates a call to the terminal according to the saved second location information and routing information.

A terminal, wherein the terminal is a single-user identity module, a SIM card terminal, and the SIM card includes a user identifier, and the terminal includes:

A mobile switching center MSC, wherein the MSC is a 2G/3G MSC that is used for both a 2G network and a 3G network, and the MSC includes: a receiving module, a sending module, a route returning module, and a call selecting module;

The receiving module is configured to: receive a 2G network location update request and a 3G network location update request sent by the terminal; the terminal is a single user identity module SIM card, and the SIM card includes a user identifier, a 2G network location update request, and a 3G network location update request. Carrying the same user identifier; and camping the terminal's circuit-switched CS domain to the 2G network and the 3G network, and storing the location information of the resident 2G network and the location information of the 3G network;

The sending module is configured to send a first network location update to the location home register HLR Requesting a second network location update request, the first network location update request carrying the user identifier, a 2G network identifier, and a 2G/3G MSC identifier, where the second network location update request carries a user identifier, a 3G network identifier And 2G/3G MSC logo;

And transmitting, by the first network location update request and the second network location update request, the HLR to save the first location information according to the received first network location update request and the second network location update, where The first location information includes a network type of the network where the terminal sends the location update request and an identifier of the MSC that receives the location update request;

The receiving module is further configured to: receive an insert user data notification sent by the HLR after receiving the first network location update request and the second network location update request, where the inserted user data notification carries the network where the terminal sends the location update request a network type, where the second location information is saved after receiving the notification, where the second location information includes the network type and location area information of the network where the terminal sends the location update request;

The receiving module is further configured to: receive a request for acquiring routing information sent by the HLR, where the HLR sends a request for obtaining routing information when the calling MSC queries the routing information request, and the calling MSC receives the calling user. When the CS domain service request is sent, a request for querying routing information is sent to the HLR;

The call selection module is configured to receive a call connection sent by the calling MSC according to the routing information, and preferentially initiate a call to the terminal through the 2G network according to the saved second location information, where the 2G network location information does not exist in the second location information or When the 2G network does not meet the CS domain service requirement, the 3G network initiates a call to the terminal through the 3G according to the saved second location information.

10. A location attribution register HLR, comprising: a location update receiving mode Block, save module and route acquisition module;

The saving module is configured to save first location information according to the received first network location update request and the second network location update request, where the first location information includes where the terminal sends a location update request The network type of the network and the identifier of the MSC receiving the location update request; and notifying the 2G MSC and the 3G MSC to insert user data, so that the 2G MSC and the 3G MSC save the second location information after receiving the notification, The second location information includes location area information of the network where the terminal sends the location update request; if the other MSC stores the old second location information, the other MSC is notified to delete the old second location information; The information includes the identifier of the MSC of the terminal in the 2G network and the 3G network; the route obtaining module is configured to receive, by the calling MSC, a request for querying routing information of the terminal, and according to the saved first location Obtaining routing information from the 2G MSC; when there is no location information or 2G corresponding to the 2G network in the first location information When the network does not meet the CS domain service requirement, the routing information is obtained from the 3G MSC; the calling MSC sends a request for querying the routing information to the HLR when receiving the CS domain service request sent by the calling user;