CN105009639A

CN105009639A - Method, device and system for selecting LTE network

Info

Publication number: CN105009639A
Application number: CN201380002743.6A
Authority: CN
Inventors: 吴晓波; 舒林; 邹烨
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2013-12-31
Filing date: 2013-12-31
Publication date: 2015-10-28
Also published as: WO2015100606A1

Abstract

Disclosed are a method, device and system for selecting an LTE network. During a CSFB process, a UE is triggered to switch from an LTE network to a CS domain of a 2G or 3G network. After a fall back via switching means to a network having a CS domain, an MSC sends a notification message to the UE, the notification message carrying a location area identity (LAI). The LAI includes a PLMN identity of the LTE network, so that the UE, according to the PLMN identity, preferentially returns to the LTE network.

Description

Method, device and system for selecting LTE network

A kind of method, equipment and the systems technology field of selection LTE network

The present invention relates to communication technical field, and in particular to method, equipment and the system of selection LTE network.

Background technology

Global system for mobile communications（Global System of Mobile communication, GSM) or WCDMA（Wideband Code Division Multiple Access, WCDMA) etc. the second generation (Second Generation, 2G) or third generation networks（Third Generation, 3G) network realizes comprehensive covering substantially.

With Long Term Evolution（Long Term Evolution, LTE) network technology development, these LTE network-covereds to some cities and traffic hot spot area, so in current communication network, LTE network and 2G or 3G network are simultaneously deposited.

User equipment (User Equipment, UE) may enter 2G or 3G network during call from LTE network, because LTE network is different from 2G or 3G network carrying mechanism, it is necessary to from packet switch（Packet Switching, PS) domain is switched to circuit switching（Circuit Switching, CS) domain, it is possible that the interruption of audio call, so as to influence the continuity that user speech is called.

Circuit domain dropping（Circuit Switched Fallback, CSFB user equipment (the User Equipment under) being covered for LTE, UE) when handling speech business, triggering UE is switched to the CS domains of 2G or 3G network from LTE network, the network with CS domains is return back to by way of switching, in the network processes speech business with CS domains.

But in the prior art, because UE is fallen back to after 2G or 3G network from LTE network switching, UE registering public land mobile network PLMN becomes the 2nd PLMN for turning to 2G or 3G networks from the first PLMN of LTE network.

When UE returns to LTE network from 2G or 3G network, because UE currently register PLMN as the 2nd PLMN, so UE can preferentially quarter at the 2nd PLMN, so as to cause UE can not return to the first PLMN, so as to cause the first PLMN operator customer loss occur in CSFB processes, so as to can not cooperate between causing operator. The content of the invention

For the above mentioned problem of prior art, the embodiment of the present invention provides a kind of method for selecting LTE network, during CSFB, the MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, so as to marks of the UE according to the PLMN, preferentially returns to the LTE network.The embodiment of the present invention additionally provides corresponding equipment and system.

First aspect present invention provides a kind of method for selecting LTE network, including：

Moving exchanging center MSC receives the first handover request message that mobile management entity MME is sent, and the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network；

The MSC receives handoff completion message, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the 2G or the CS domains of 3G network；

The MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network to be returned to.

With reference in a first aspect, in the first possible implementation,

The notification message is that TMSI reassigns message.

Second aspect of the present invention provides a kind of method for selecting LTE network, including：

User equipment (UE) positioned at Long Term Evolution LTE network is to mobile management entity MME transmission request message, and the request message is used for request circuit domain dropping CSFB;

The UE receives the switching command that evolution base station eNodeB is sent, and the switching command is used for the circuit-switched CS domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network；

According to the switching command, the UE is switched to the CS domains of the 2G or 3G network from the LTE network；

The UE receives the notification message that the MSC is sent, and the notification message includes Location Area Identification

The PLMN of LAI, the LAI comprising the LTE network is identified；

The UE selects the LTE network to be returned to according to the mark of the PLMN.

With reference to second aspect, in the first possible implementation, methods described also includes： The UE receives the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, and the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE networks to be returned to of the UE according to the PLMN.

With reference to second aspect or second aspect the first possible implementation, in second of possible implementation,

The notification message is that TMSI reassigns message.

Third aspect present invention provides a kind of moving exchanging center MSC, including：

Receiving unit, the first handover request message and handoff completion message for receiving mobile management entity MME transmission, the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the CS domains of the 2G or 3G networks；

Generation unit, the handoff completion message for being received according to the receiving unit generates notification message, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network to be returned to；

Transmitting element, the notification message for sending the generation unit generation.

With reference to the third aspect, in the first possible implementation,

The notification message is that TMSI reassigns message.

Fourth aspect present invention provides a kind of user equipment (UE), including：

Transmitting element, for sending request message to mobile management entity MME, the request message is used for request circuit domain dropping CSFB;

Receiving unit, the switching command for receiving evolution base station eNodeB transmissions, the switching command is used for the circuit switching (CS) domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network；

Switch unit, for the switching command received according to the receiving unit, the CS domains of the 2G or 3G network are switched to from the LTE network；

The receiving unit, is additionally operable to receive the notification message that the MSC is sent, the notification message bag The PLMN of LAI containing Location Area Identification, the LAI comprising the LTE network is identified；

Selecting unit, for the PLMN received according to the receiving unit mark, selects the LTE network to be returned to.

With reference to fourth aspect, in the first possible implementation,

The receiving unit, it is additionally operable to receive the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE network to be returned to for the PLMN that the selecting unit is received according to the receiving unit.

The embodiment provided by the present invention, during CSFB, the MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, so as to marks of the UE according to the PLMN, the LTE network is preferentially returned to.

Brief description of the drawings

Technical scheme in order to illustrate the embodiments of the present invention more clearly, the accompanying drawing used required in being described below to embodiment is made cylinder and singly introduced, apparently, drawings in the following description are only some embodiments of the present invention, for those skilled in the art, on the premise of not paying creative work, other accompanying drawings can also be obtained according to these accompanying drawings.

Fig. 1 is an embodiment schematic diagram of the method for selection LTE network in the embodiment of the present invention；

Fig. 2 is another embodiment schematic diagram of the method for selection LTE network in the embodiment of the present invention；Fig. 3 is another embodiment schematic diagram of the method for selection LTE network in the embodiment of the present invention；Fig. 4 is another embodiment schematic diagram of the method for selection LTE network in the embodiment of the present invention；Fig. 5 is another embodiment schematic diagram of selection LTE network in the embodiment of the present invention；

Fig. 6 is another embodiment schematic diagram of selection LTE network in the embodiment of the present invention；

Fig. 7 is an embodiment schematic diagram of mobile switching centre in the embodiment of the present invention；

Fig. 8 is an embodiment schematic diagram of user equipment in the embodiment of the present invention；

Fig. 9 is an embodiment schematic diagram of system in the embodiment of the present invention.

Embodiment

The embodiment of the present invention provides a kind of method for selecting LTE network, during CSFB, the MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, so as to marks of the UE according to the PLMN, preferentially return to The LTE network.The embodiment of the present invention additionally provides corresponding equipment and system.It is described in detail individually below.

The present embodiments relate to section communication noun bilingual and abbreviation include：Mobile management entity (Mobile Managenment Entity, MME), evolution base station (Envolved NodeB, eNodeB), user equipment（User Equipment, UE), mobile switching centre（Mobile Services Switching Centre, MSC), the second generation or 3rd generation mobile communication technology（2rd Generation/3rd Generation, 2G or 3G), base station（Base Station, BS), the base station in the embodiment of the present invention include base station controller（Base Station Controller, BSC) and radio network controller（ Radio Network Controller, RNC);Long Term Evolution（Long Term Evolution, LTE), serving GRPS support node（Serving GPRS Support Node, SGSN), circuit domain dropping（Circuit Switched Fallback, CSFB), land radio access web（Terrestrial Radio Access Network, UTRAN), global system for mobile communications（Global System of Mobile communication, GSM), enhanced data rates for gsm evolution technology（EnhancedDataRateforGSMEvolution, EDGE) global system for mobile communications/enhanced data rates for gsm evolution technology Radio Access Network（ GSM / EDGE Radio Access Network, GERAN ).

First, second, third, fourth, 5th etc. in the embodiment of the present invention is only used for distinguishing different configured information, message or other objects, does not represent ordinal relation.

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those skilled in the art are obtained under the premise of creative work is not made belongs to the scope of protection of the invention.

Refering to Fig. 1, Fig. 1 be in the embodiment of the present invention UE by be switched to from LTE network the realization of 2G or 3G network falling process and switching after active call process and caller process after return to the process of LTE network：S100, UE send request of activating business to MME, and the request of activating business is used for request circuit domain dropping CSFB.

S100a, MME may determine that whether LTE network and 2G or 3G network support that UE is switched to the CS domains of 2G or 3G network for CSFB from LTE network.

MME can also without judging, but it is default think that communication network is supported will be described for the CSFB UE is switched to the CS domains of the 2G or 3G network from the LTE network, or only some networks therein are judged.

The communication network is the LTE network and the 2G or 3G network.

S105, MME activate business request according to, sent a notification message to evolution base station eNodeB, the notification message is used for the CS domains for indicating that the UE is moved to 2G or 3G network for the CSFB by the eNodeB from LTE network, it is, notification message is used to indicate that the eNB should be moved to 2G or 3G network for UE described in the CSFB.

When MME judges that LTE network and 2G or 3G network support that the UE is switched to the CS domains of the 2G or 3G network for the CSFB from the LTE network, MME can inform that network is switched to the CS domains of 2G or 3G network by sending a notification message, so that eNodeB is initiated as the switching requirement that the UE is switched to the CS domains of 2G or 3G network by the CSFB from the LTE network.

S 110, evolution base station eNodeB send switching to MME and require message.

The switching requires that message can be to require message from the LTE network to the switching of the packet switched ps domain of the 2G or 3G network,（For example：LTE to 2/3G PS HO Required message), or message is required from the LTE networks to the switching of the CS domains of the 2G or 3G network,（For example：LTE to 2/3G SRVCC HO Required message）, or from the LTE network to the 2G or the ps domain of 3G network and the CS domains switching require message,（For example：LTE to 2/3G SRVCC and PS HO Required message）.

The switching requires that message can include UE ability informations, for indicate band information, access that UE supported can etc..For example, the UE ability informations can be at least one in 3 (classmark3) of class 2 (classmark2) of mark and class mark.In the prior art, when UE does not support that LTE network switches to the CS of 2G/3G networks, eNodeB will not issue UE ability information MME, therefore MME does not have UE ability information.But in MME after UE ability information is got, UE ability information can be sent to MSC by MME, so that MSC can go to 2G/3G CS switchings.In embodiments of the present invention, UE ability informations can be passed to by MME by handover request message.

S115, MME send the first handover request message to MSC, and the first handover request message is used for the circuit-switched CS domain for 3G network. MSC is issued because the first handover request message is MME, therefore the switching of the first handover request message calls is from LTE network to 2G or the switching in the CS domains of 3G network, i.e., first handover request is PS to CS handover request.

The first handover request message can carry the 3rd configured information, and the 3rd configured information is used for please

CS domains, that is to say, that represent that first handover request sends for CSFB by the 3rd configured information.3rd configured information also can indicate that the UE supports to be switched to 2G the or 3G network Cs S domains from the LTE network.The first handover request message can not also indicate CSFB, and now MSC is default thinks that the first handover request sends for CSFB.

After MME receives UE ability information from eNodeB, the first handover request message can be carried

UE ability informations, for example, the ability information identifies at least one in classmark2 and class mark classmark3 for class.

S120, MME send the second handover request message to SGSN, and the second handover request message is used to ask the SGSN to initiate from the LTE network to the switching of the 2G or the packet switched ps domain of 3G network.

UE from LTE network be switched to CS domains when, ps domain can be switched to simultaneously, ps domain is switched to when can also be different.This programme can so be reduced to network dependency degree, that is, only require that operator supports the CS domains switching of LTE to 2G or 3G network, without forcing operator to support the ps domain switching of LTE to 2G or 3G network.

S121, MSC send the 3rd handover request message to base station, and the 3rd handover request message is used for the CS domains distribution CS domains resource for asking the base station to be switched to the 2G or 3G network for the UE.

The 3rd handover request message is additionally operable to the circuit-switched CS domain for asking the base station that user equipment (UE) is switched to the 2G or 3G network for CSFB from Long Term Evolution LTE network.Base station is the CS domains distribution CS domains resource that the UE is switched to the 2G or 3G network from LTE network.For example, the CS languages resource of base station distribution includes the Radio Resource between cable resource and base station and UE between base station and MSC.

S125, base station send the 3rd handover request ack message to MSC, the information of CS domains Radio Resource is included in 3rd handover request ack message, the information of CS domains Radio Resource is used for the CS domains that the UE is switched to the 2G or 3G network from the LTE network. S130, MSC send the information for including CS domains Radio Resource in the first switching response message, first switching response message to MME.

S135a, MME send switching to eNodeB and require response message, and the switching requires to include the information of CS domains Radio Resource in response message.

S135b, eNodeB send the information for including CS domains Radio Resource in switching command, the switching command to UE.

The switching command may be used to indicate that the UE is switched to the ps domain of the 2G or 3G network from the LTE network.

S140, UE are switched to the CS domains of the 2G or 3G network from the LTE network according to switching command.

UE, using the information of the resource included in switching command, is the CS domains that the CSFB is switched to the 2G or 3G network from the LTE network.

UE generates the 3rd session during the 2G or 3G network CS domains are switched to from the LTE network.UE can not also generate session being switched to from the LTE network during the 2G or 3G network CS domains.

When the packet encryption algorithm identification containing CS of the resource, the UE activates the encryption of CS domains according to the CS encryption algorithm identifications during the 2G networks or 3G network is switched to from the LTE network.

After the completion of S145, UE switching, to base station（BSC or RNC) send switching completion（HO Complete) message.

Or, when UE sends LAU message to base station, to avert failure, base station does not send location update request message to the MSC, and base station directly transmits location updating and accepts message to the UE.

Handoff completion message in step S145 is transmitted to MSC by S150, base station.

S155, UE send connection management service request to MSC（ CM Serivce Request ).

S160, MSC send authentication request (Authenticate Request) to UE.

This step S160 can not also be performed, i.e.,：The MSC does not send authentication request message to the UE.

S165, UE send Authentication Response (Authenticate Response) to MSC.

S170, MSC send safe mode command (Security mode command) to base station, carry complete raw protection information, (Integrity Protection Information) and/or power mouthful confidential information, (Encryption ), Information so that base station sends safe mode command to UE.

This step S170 can not also be performed, i.e.,：The MSC does not send safe mode command to the base station.

S175, base station send safe mode command to UE.Particularly, safe mode command of the base station in step S170, performs this step, or base station performs this step after S145 message is received.

S180, alternatively, MSC sends connection management business (CM service Accept) S185, the UE that take orders to UE and sends the first CS calling connections to MSC and set up request message (Setup), and the first CS calling connections, which set up request message, to be used to ask the MSC to generate the first session for the CSFB.Or, the first CS calling connections, which set up request message, to be used to ask the MSC to generate the 3rd session for the CSFB.

S190, MSC receive the first CS calling connections and set up after request message, if the first CS calling connections, which set up request message, to be used to ask the MSC to generate the first session for the CSFB, the first session release message is sent to the UE, the first session release message is being switched to the 3rd session generated during the 2G or 3G network CS domains from the LTE network for asking the UE to discharge the UE.

If the first CS calling connections, which set up request message, to be used to ask the MSC to generate the 3rd session for the CSFB, MSC need not send the first session release message to the UE.

5195th, MSC carries out the processing of calling opposite end.

5196th, MSC sends ring (Alerting) message to UE.UE waits opposite end response message.

Further, off-hook is called, into talking state.

S198, MSC send another notification message to the UE, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Particularly, another notification message carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, registration PLMN (Registed PLMN for indicating the UE, RPLMN) identified for the PLMN of LTE network, or, another notification message carries the PLMN information of LTE network, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Alternatively, another notification message carry equivalence PLMN (Equivalent PLMN, EPLMN) list is to UE.

Particularly, another notification message can reassign message for TMSI（TMSI Reallocation Request, Temporary Mobile Subscriber Identities Reallocation Request) give UE, the TMSI reassigns message and carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Alternatively, the TMSI, which is reassigned, carries equivalence PLMN (Equivalent PLMN, EPLMN) list, wherein the PLMN that equivalence PLMN includes LTE network is identified.

Note, S198 can any moment transmission after S150 step message is received.

Wherein, UE is when attachment is combined, and MME is in location update message is sent by LTE network

PLMN information brings MSC, so that MSC knows the PLMN information of the LTE network.

S199, UE select the LTE network to be returned to according to the mark of the PLMN.

After end of calling, because the calling is triggered by CSFB, UE needs to return to LTE network after completing calling.Base station is according to the 3rd handover request message, determine that the calling is triggered by CSFB, the base station of the 2G or 3G network are after the call release message that the MSC is sent is received, the base station of the 2G or 3G networks UE is redirected to the LTE network, or, the UE is switched to the LTE network by the base station, and the call release message is release command Iu Release Command or clear command Clear Command.

Now, UE registers PLMN (Registed PLMN, RPLMN) and identified for the PLMN of LTE network, so when UE returns to LTE network, UE can preferentially quarter at the LTE PLMN.Wherein, the base station of 2G or 3G networks, which is sent, redirects message (RRC Release with Redirection or RRC Release) instruction UE return LTE networks.

Particularly, if the notification message carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, or, the notification message carries the PLMN information of LTE network, then the UE thinks that currently registering the PLMN that PLMN (Registed PLMN, RPLMN) is LTE network identifies.

It should be noted that in the present embodiment, base station can parse the CS signalings between UE and MSC.Base station receives the signaling message that UE is sent to MSC, such as connection management service request, Authentication Response, first CS calling connections set up the signaling messages such as request message.Base station can use the connection set up in the handoff procedure in the CS domains in LTE network to 2G or 3G network that the signaling message is sent into MSC, or the signaling message is sent into MSC using direct-sending message.

In Fig. 1, during CSFB, the MSC sends another notification message to the UE, another notification message carries Location Area Identification LAI, the PLMN comprising the LTE network identifies so as to marks of the UE according to the PLMN in the LAI, so as to preferentially return to the LTE network.Refering to Fig. 2, Fig. 2 selects the process that LTE network is returned to after passive calling procedure and called process after process and network switching for network switching in the embodiment of the present invention：

S0b-S0c:MSC sends CS paging requests to MME, MME triggering pagings.

Step S200-S250 is identical with the step S100-S150 in Fig. 1, will not be repeated here.

S255, UE send page response to MSC.

S260, MSC send authentication request to UE.

This step S260 can not also be performed, i.e.,：The MSC does not send authentication request message to the UE.S265, UE send Authentication Response to MSC.

S270, MSC send safe mode command to base station; integrity protection information (Integrity Protection Information) and/or power mouthful confidential information (Encryption Information) are carried, safe mode command is sent to UE with 1 ^ stations.

This step S270 can not also be performed, i.e.,：The MSC does not send safe mode command to the base station.

S275, base station send safe mode command to UE.Particularly, safe mode command of the base station in step S270, performs this step, or base station performs this step after S245 message is received.

S280, MSC send the 2nd CS calling connections to UE and set up request message, and the 2nd CS calling connections, which set up request message, to be used to ask the UE to generate the second session for the CSFB.Or, the 2nd CS calling connections, which set up request message, to be used to ask the UE to generate the 3rd session for the CSFB.

After the step of UE the 2nd CS calling connections for receiving moving exchanging center MSC transmission set up request message, in addition to：

The UE is received or sent the session data of second session using the resource. S285, MSC receive the confirming call message that UE is sent.

If S290, the 2nd CS calling connections, which set up request message, to be used to ask the UE to generate the second session for the CSFB, MSC sends the second session release message to UE, and second session discharges the 3rd session generated during the CS domains that disappear.

If the 2nd CS calling connections, which set up request message, to be used to ask the UE to generate the 3rd session for the CSFB, MSC need not send the second session release message to the UE.

The UE receives the session release message that the MSC is sent.

S295, MSC send ring (Alerting) message to UE.UE enters talking state.

S296, MSC trigger opposite end ring.

S298, MSC send another notification message to the UE, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Alternatively, another notification message carries equivalence PLMN (Equivalent PLMN, EPLMN) list to UE.

Particularly, another notification message can reassign message for TMSI（ TMSI Reallocation

Request, Temporary Mobile Subscriber Identities Reallocation Request) give UE, the TMSI reassigns message and carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Alternatively, the TMSI reassign message carry equivalence PLMN (Equivalent PLMN,

EPLMN) list is to UE, wherein the PLMN that equivalence PLMN includes LTE network is identified.

Note, S298 can any moment transmission after S250 step message is received.

Wherein, UE is when attachment is combined, and MME is in location update message is sent by LTE network PLMN information brings MSC, so that MSC knows the PLMN information of the LTE network.

S299, UE select the LTE network to be returned to according to the mark of the PLMN.

After end of calling, because the calling is triggered by CSFB, UE needs to return to after completing calling

LTE network.Base station determines that the calling is triggered by CSFB according to the 3rd handover request message, therefore, the base station of the 2G or 3G network after the call release message that the MSC is sent is received, the 2G or

The UE is redirected to the LTE network by the base station of 3G network, or, the UE is switched to the LTE network by the base station, and the call release message is release command Iu Release Command or clear command Clear Command.

Particularly, if another notification message carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, or, another notification message carries the PLMN information of LTE networks, then the UE thinks that currently registering the PLMN that PLMN (Registed PLMN, RPLMN) is LTE network identifies.

In fig. 2, during CSFB, the MSC sends another notification message to the UE, another notification message carries Location Area Identification LAI, the PLMN comprising the LTE network identifies so as to marks of the UE according to the PLMN in the LAI, so as to preferentially return to the LTE network.Refering to Fig. 3, Fig. 3 be in the embodiment of the present invention UE by be switched to from LTE network the realization of 2G or 3G network falling process and switching after active call process and caller process after return to the process of LTE network：Wherein, step H100 and HlOOa is identical with the step S100 and S100 in Fig. 1, and here is omitted.

H105, MME activate business request according to, the first notification message is sent to evolution base station eNB, first notification message is used to indicate that the UE is moved to 2G or 3G network by the evolution base station eNB for the CSFB from LTE network, it is, the first notification message is used to indicate that the eNB should be moved to 2G or 3G network for UE described in the CSFB.

H110 and H115 is identical with the step S110 and S115 in Fig. 1, and here is omitted. H120, MME send the handover request message from PS to PS to SGSN, and the handover request message from PS to PS is used to ask the SGSN to initiate from the LTE network to the switching of the 2G or the packet switched ps domain of 3G network.

Step H120 is optional step, when network prepares UE being switched to CS domains from LTE network, can be also switched to ps domain, can also not switch to ps domain.

H121, MSC are to 2G or 3G network base station（BSC or RNC) the second handover request message is sent, the second handover request message is used for the CS domains for asking the base station that the UE is switched to 2G or 3G network from LTE network.

H125, base station send the second switching request acknowledgement message to MSC, second switching request acknowledgement message includes RAB RAB, and the UE is using the RAB for the CSFB from the LTE network switchings to the 2G or 3G network ps domain.

H130, MSC send to MME and the RAB are included in the first handover request ack message, first handover request ack message.

H135a, MME send switching to eNB and require response, and the switching requires to include the RAB in response order.

HI 35b, eNB send to UE and the RAB are included in switching command, the switching command.

Alternatively, before eNB sends the switching command to the UE, eNB determines that the UE is supported from the LTE network to the switching of the 2G or the ps domain of 3G network.

H140, UE, according to the RAB included in switching command, are the ps domain that the CSFB is switched to the 2G or 3G network from the LTE network.

After the completion of H145, UE switching, handoff completion message is sent to base station（ HO Complete ).

Alternatively, base station is received after handoff completion message, can use the CS RAB generated in step H125.When in step H125 without generation CS RAB, base station can set up a new CS RAB.

Handoff completion message in step S145 is transmitted to MSC by H150, base station.

H155-H185 is identical with the step S155 and S185 in Fig. 1, and here is omitted.

H185a, MSC are sent in call treatment（Call proceeding) message is to UE.

H190, base station send second notification message to UE.

UE can send the second push-notification-answer message to base station. In order to which the existing handling process with UE is matched to greatest extent, reduce abnormal, avoid call failure, received in the base station in the call setup message of the UE transmissions or the call treatment of MSC transmissions after message, the base station sends second notification message to the UE, the second notification message includes the CSRAB, the CS RAB as described in the CS RAB or step H145a described in step H125 that the base station is that the UE is distributed.The second notification message can be set up or radio bearer reconfiguration message for radio bearer.UE can use CS RAB to carry out voice call.

The base station can also send the second notification message after the third notice message of MSC transmissions is received.The MSC sends second notification message to the base station after receiving at least one following message, and the second notification message is used to ask the base station to be UE distribution CS domains resource.

Wherein, the following message includes：The handoff completion message that the base station is sent, the connection management business request information that the UE is sent, the first CS call connection request message that the UE is sent.

H195, MSC send ring (Alerting) message to UE.UE waits opposite end response message.

After called off-hook, calling and called enter talking state.

UE off-hooks, into talking state.

H198, MSC send third notice message to the UE, the registration for indicating the UE

PLMN (Registed PLMN, RPLMN) identifies for the PLMN of LTE network.

Particularly, the third notice message carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, registration PLMN (Registed PLMN for indicating the UE, RPLMN) identified for the PLMN of LTE network, or, the third notice message carries the PLMN information of LTE network, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Alternatively, the third notice message carries equivalence PLMN (Equivalent PLMN, EPLMN) list to UE.

Particularly, the third notice message can reassign message for TMSI（TMSI Reallocation Request, Temporary Mobile Subscriber Identities Reallocation Request) give UE, the TMSI reassigns message and carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network. Alternatively, the TMSI reassigns message and carries equivalence PLMN (Equivalent PLMN, EPLMN) lists to UE, wherein the PLMN that equivalence PLMN includes LTE network is identified.

Note, H198 can any moment transmission after H150 step message is received.

Wherein, UE is when attachment is combined, and the PLMN information of LTE network is brought MSC by MME in location update message is sent, so that MSC knows the PLMN information of the LTE network.

H199, UE select the LTE network to be returned to according to the mark of the PLMN.

In figure 3, during CSFB, the MSC sends third notice message to the UE, the third notice message carries Location Area Identification LAI, the PLMN comprising the LTE network identifies so as to marks of the UE according to the PLMN in the LAI, so as to preferentially return to the LTE network.Refering to Fig. 4, Fig. 4 selects the process that LTE network is returned to after passive calling procedure and called process after process and network switching for network switching in the embodiment of the present invention：

H0b-H0c:MSC sends CS paging requests to MME, MME triggering pagings.Step H200-H250 is identical with the step H100-H150 in Fig. 3, will not be repeated here.

H255, UE send page response to MSC.

H260, alternatively, MSC send authentication request to UE.

H265, alternatively, UE send Authentication Response to MSC.

H270, MSC send safe mode command to base station; integrity protection information (Integrity Protection Information) and/or power mouthful confidential information (Encryption Information) are carried, safe mode command is sent to UE with 1 ^ stations.

This step H270 can not also be performed, i.e.,：The MSC does not send safe mode command to the base station.

H275, base station send safe mode command to UE.Particularly, base station is according in step H270 Safe mode command, performs this step, or base station performs this step after H245 message is received.H280, MSC send the 2nd CS calling connections to UE and set up request message, and the 2nd CS calling connections, which set up request message, to be used to ask the UE to generate the second session.

Note, except CS call in addition to, MSC can also 2G/3G networks to UE initiate CS supplementary service requests, than:Mouth location service request, or USSD (UnstmcturedSupplementaryServiceData, unstructured supplementary data traffic service request.That is, it can be because MSC will initiate CS callings in 2G or 3G network or initiate CS supplementary service requests that UE retracts from LTE network execution circuit.

H285, MSC receive the confirming call message that UE is sent.

H290, base station send second notification message to UE.UE can send the second push-notification-answer message to base station.

In order to which the existing handling process with UE is matched to greatest extent, reduce abnormal, avoid call failure, received in the base station after the call setup message of the MSC transmissions or the confirming call message of UE transmissions, the base station sends second notification message to the UE, the second notification message includes the CSRAB, the CS RAB as described in the CS RAB or step H245a described in step H225 that the base station is that the UE is distributed.The second notification message can be set up or radio bearer reconfiguration message for radio bearer.UE can use CS RAB to carry out voice call.

Wherein, the following message includes：The handoff completion message that the base station is sent, the page response that the UE is sent, the 2nd CS call connection request message that the MSC is sent.

H295, MSC send ring (Alerting) message to UE.

UE off-hooks, into talking state.

H298, MSC send third notice message to the UE, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Particularly, the third notice message carries Location Area Identification LAI, PLMN information is the PLMN information of LTE network in wherein described Location Area Identification, registration PLMN (Registed PLMN for indicating the UE, RPLMN) identified for the PLMN of LTE network, or, the threeway Know that message carries the PLMN information of LTE network, for indicating that the registration PLMN (Registed PLMN, RPLMN) of the UE identifies for the PLMN of LTE network.

Particularly, the third notice message can reassign message for TMSI（ TMSI Reallocation

Note, H298 can any moment transmission after H250 step message is received.

H299, UE select the LTE network to be returned to according to the mark of the PLMN.

In Fig. 4, during CSFB, the MSC sends third notice message to the UE, and the third notice message carries the PLMN comprising the LTE network in Location Area Identification LAI, the LAI and identified_:So as to marks of the UE according to the PLMN, so as to preferentially return to the LTE network.

Refering to Fig. 5, one embodiment of the method for selection LTE network provided in an embodiment of the present invention includes：101st, the first handover request that moving exchanging center MSC reception mobile management entity MME is sent disappears Breath, the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network.

102nd, the MSC receives handoff completion message, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the 2G or the CS domains of 3G network.

103rd, the MSC sends a notification message to the UE, and the notification message carries Location Area Identification

The PLMN comprising the LTE network is identified in LAI, the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network to be returned to.

The notification message is that TMSI reassigns message.The description seen in the embodiment corresponding to Fig. 1-Fig. 4, here is omitted.

Refering to Fig. 6, another embodiment of the method for selection LTE network provided in an embodiment of the present invention includes：201st, the user equipment (UE) positioned at Long Term Evolution LTE network is to mobile management entity MME transmission request message, and the request message is used for request circuit domain dropping CSFB.

202nd, the UE receives the switching command that evolution base station eNodeB is sent, and the switching command is used for the circuit switching (CS) domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network.

203rd, according to the switching command, the UE is switched to the CS domains of the 2G or 3G network from the LTE network.

204th, the UE receives the notification message that the MSC is sent, and the notification message includes Location Area Identification LAI, and PLMNs of the LAI comprising the LTE network is identified.

The UE receives the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, and the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE networks to be returned to of the UE according to the PLMN.

The notification message is that TMSI reassigns message.

The above-mentioned process step and the detailed description of other process steps of user equipment, may refer to the description in the embodiment corresponding to Fig. 1-Fig. 4, here is omitted in the present embodiment.

Refering to Fig. 7, moving exchanging center MSC 80 provided in an embodiment of the present invention includes：Receiving unit 801, Generation unit 802 and transmitting element 803.

Receiving unit 801, the first handover request message and handoff completion message for receiving mobile management entity MME transmission, the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the 2G or the CS domains of 3G network.

Generation unit 802, the handoff completion message for being received according to the receiving unit 801 generates notification message, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network source to be returned to.

Transmitting element 803, for sending the notification message that the generation unit 802 is generated.

The notification message is that TMSI reassigns message；

The notification message carries equivalence PLMN lists, wherein the PLMN that the PLMN lists of equal value include the LTE network is identified.

MSC in the present embodiment can perform the method and step of the MSC described in Fig. 1-Fig. 5 embodiments of the method, and receiving unit 801 is used to receiving the message that other entities are sent to MSC, transmitting element 803 be used for

Refering to Fig. 8, user equipment 90 provided in an embodiment of the present invention includes：Transmitting element 901, receiving unit 902, switch unit 903 and selecting unit 904.

Transmitting element 901, for sending request message to mobile management entity MME, the request message is used for request circuit domain dropping CSFB.

Receiving unit 902, the switching command for receiving evolution base station eNodeB transmissions, the switching command is used for the circuit-switched CS domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network.

Switch unit 903, for the switching command received according to the receiving unit 901, the CS domains of the 2G or 3G network are switched to from the LTE network.

The receiving unit 902, is additionally operable to receive the notification message that the MSC is sent, the notification message Comprising Location Area Identification LAI, PLMNs of the LAI comprising the LTE network is identified.

Selecting unit 904, for the PLMN received according to the receiving unit 902 mark, selects the LTE network to be returned to.

The receiving unit 902, it is additionally operable to receive the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE networks to be returned to for the PLMN that the selecting unit 904 is received according to the receiving unit 902.

UE in the present embodiment can perform the method and step of the UE described in Fig. 1-Fig. 4 and Fig. 6 embodiments of the method, and receiving unit 902 is used to receive the message that other entities are sent to UE, and transmitting element 901 is used for it

The said apparatus embodiment provided by the present invention, during CSFB, the MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE networks is identified in the LAI, so as to marks of the UE according to the PLMN, the LTE networks are preferentially returned to.

It will be appreciated by those skilled in the art that in above-mentioned Fig. 7 and Fig. 8 embodiment, the transmitting element for sending message can be realized using transmitter, the receiving unit for receiving message can be realized using receiver.Or, transmitting element and receiving unit can be realized using transceiver.In physics realization, transmitter or transceiver can be realized with a physical entity, can also be realized using multiple physical entities, and transmitter and transceiver can be realized using a physical entity, it can also be realized using multiple physical entities, the present invention is without limitation.Other units, such as generation unit, allocation unit, redirection unit, switch unit, determining unit unit can realize that the present invention is without limitation using one or more processors.

Refering to Fig. 9, an embodiment of the system of selection LTE network provided in an embodiment of the present invention includes：Mobile management entity 60, evolution base station 70, mobile switching centre 80, base station 100 and user equipment 90;

Action and the interaction between them that mobile management entity 60, evolution base station 70, mobile switching centre 80, base station 100 and user equipment 90 are each performed, it may refer to Fig. 1-Fig. 4 description, and the description of Fig. 5 to Fig. 8 embodiment of the method and device embodiment, here is omitted.Those of ordinary skill in the art with reference to what the embodiments described herein was described it is to be appreciated that respectively show The unit and algorithm steps of example, it can be realized with electronic hardware, computer software or the combination of the two, in order to clearly demonstrate the interchangeability of hardware and software, the composition and step of each example are generally described according to function in the above description.These functions are performed with hardware or software mode actually, depending on the application-specific and design constraint of technical scheme.Professional and technical personnel can realize described function to each specific application using distinct methods, but this realization is it is not considered that beyond the scope of this invention.It is apparent to those skilled in the art that, clean with cylinder for convenience of description, the specific work process of the system of foregoing description, device and unit may be referred to the corresponding process in preceding method embodiment, will not be repeated here.In several embodiments provided herein, it should be understood that disclosed systems, devices and methods, it can realize by another way.For example, device embodiment described above is only schematical, for example, the division of the unit, it is only a kind of division of logic function, there can be other dividing mode when actually realizing, such as multiple units or component can combine or be desirably integrated into another system, or some features can be ignored, or do not perform.In addition, shown or discussed coupling or direct-coupling or communication connection each other can be by the INDIRECT COUPLING of some interfaces, device or unit or communication connection or electricity, mechanical or other forms are connected.The unit illustrated as separating component can be or may not be physically separate, and the part shown as unit can be or may not be physical location, you can with positioned at a place, or can also be distributed on multiple NEs.Some or all of unit therein can be selected to realize the purpose of scheme of the embodiment of the present invention according to the actual needs.In addition, each functional unit in each embodiment of the invention can be integrated in a processing unit or unit is individually physically present or two or more units are integrated in a unit.Above-mentioned integrated unit can both be realized in the form of hardware, it would however also be possible to employ the form of SFU software functional unit is realized.If the integrated unit is realized using in the form of SFU software functional unit and as independent production marketing or in use, can be stored in a computer read/write memory medium.Understood based on such, this hair The part that bright technical scheme substantially contributes to prior art in other words, or all or part of the technical scheme can be embodied in the form of software product, the computer software product is stored in a storage medium, including some instructions are to cause a computer equipment（Can be personal computer, server, or network equipment etc.）Perform all or part of step of each embodiment methods described of the invention.And foregoing storage medium includes：USB flash disk, mobile hard disk, read-only storage（ROM, Read-Only Memory), random access memory（RAM, Random Access Memory), magnetic disc or CD etc. are various can be with the medium of store program codes.The LTE network being previously mentioned in the present invention, including LTE A networks and subsequently it is likely to occur LTE versions.It is described above; only embodiment of the invention; but protection scope of the present invention is not limited thereto; any one skilled in the art the invention discloses technical scope in; various equivalent modifications or substitutions can be readily occurred in, these modifications or substitutions should be all included within the scope of the present invention.Therefore, protection scope of the present invention should be defined by scope of the claims.

Claims

Claim

1st, a kind of method for selecting LTE network, it is characterised in that including：

Moving exchanging center MSC receives the first handover request message that mobile management entity MME is sent, and the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network；

The MSC receives handoff completion message, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the 2G or the CS domains of 3G network；

The MSC sends a notification message to the UE, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network to be returned to.

2nd, according to the method described in claim 1, it is characterised in that

The notification message is that TMSI reassigns message.

3rd, a kind of method for selecting LTE network, it is characterised in that including：

User equipment (UE) positioned at Long Term Evolution LTE network is to mobile management entity MME transmission request message, and the request message is used for request circuit domain dropping CSFB;

The UE receives the switching command that evolution base station eNodeB is sent, and the switching command is used for the circuit-switched CS domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network；

According to the switching command, the UE is switched to the CS domains of the 2G or 3G network from the LTE network；

The UE receives the notification message that the MSC is sent, and the notification message includes Location Area Identification LAI, and PLMNs of the LAI comprising the LTE network is identified；

The UE selects the LTE network to be returned to according to the mark of the PLMN.

4th, method according to claim 3, it is characterised in that methods described also includes：The UE receives the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, and the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE networks to be returned to of the UE according to the PLMN.

5th, the method according to claim 3 or 4, it is characterised in that The notification message is that TMSI reassigns message.

6th, a kind of moving exchanging center MSC, it is characterised in that including：

Receiving unit, the first handover request message and handoff completion message for receiving mobile management entity MME transmission, the first handover request message is used for the circuit-switched CS domain for asking the MSC that user equipment (UE) is switched to second generation 2G or third generation 3G network for circuit domain dropping CSFB from Long Term Evolution LTE network, and the handoff completion message indicates that the UE has completed the switching from the LTE network to the CS domains of the 2G or 3G networks；

Generation unit, the handoff completion message for being received according to the receiving unit generates notification message, the notification message carries Location Area Identification LAI, the PLMN comprising the LTE network is identified in the LAI, and the PLMN of the LTE network is identified for indicating the UE according to the PLMN of the LTE network mark selections LTE network to be returned to；

Transmitting element, the notification message for sending the generation unit generation.

7th, mobile switching centre according to claim 6, it is characterised in that

The notification message is that TMSI reassigns message.

8th, a kind of user equipment (UE), it is characterised in that including：

Transmitting element, for sending request message to mobile management entity MME, the request message is used for request circuit domain dropping CSFB;

Receiving unit, the switching command for receiving evolution base station eNodeB transmissions, the switching command is used for the circuit switching (CS) domain for indicating that the UE is switched to 2G or 3G network for the CSFB from the LTE network；

Switch unit, for the switching command received according to the receiving unit, the CS domains of the 2G or 3G network are switched to from the LTE network；

The receiving unit, is additionally operable to receive the notification message that the MSC is sent, the notification message includes Location Area Identification LAI, and PLMNs of the LAI comprising the LTE network is identified；

Selecting unit, for the PLMN received according to the receiving unit mark, selects the LTE network to be returned to. 9th, user equipment according to claim 8, it is characterised in that

The receiving unit, it is additionally operable to receive the redirection message or connection release message of eating dishes without rice or wine of the base station transmission of the 2G or 3G network, the redirection message or connection release message of eating dishes without rice or wine trigger the mark selection LTE network to be returned to for the PLMN that the selecting unit is received according to the receiving unit.