CN100502566C

CN100502566C - Method for realizing roam of group-calling

Info

Publication number: CN100502566C
Application number: CNB2005100886969A
Authority: CN
Inventors: 柳光; 陈德
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2005-08-01
Filing date: 2005-08-01
Publication date: 2009-06-17
Anticipated expiration: 2025-08-01
Also published as: CN1909720A

Abstract

The invention relates to a roaming method of group call, which comprises: A, the user terminal detects the change of its position, to report the roaming refresh message with contract group number ID to local mobile exchange center MSC; B, local MSC receives said roaming refresh message to judge if the position of user terminal is the roaming position of the group call marked by the group ID of said message; if it is, obtaining the position, and using it as the temporary group call region to be stored. The invention can initialize and receive group call at the roaming region of grouped user terminals.

Description

A kind of roaming implementation method of group calling

Technical field

The present invention relates to the communication technology in the wireless trunking communication system, relate in particular to a kind of roaming implementation method when wireless trunking communication system carries out group calling.

Background technology

Wireless trunking communication system (this paper is called for short group system) is a kind of less expensive of growing up in recent years, command dispatching and communication system more flexibly, be widely used in units such as government bodies, energy traffic, airport harbour, industrial and mining enterprises, fire-fighting police, water conservancy and military affairs, to satisfy the needs of constituent parts intercommunication.

In the present trunked communication system, each group comprises a group id ID and group call region, and wherein group call region is defined as the gang sub-district.

Fig. 1 is the structure chart of current cluster system.Referring to Fig. 1, group system mainly comprises user terminal (UE), Access Network part 11 and core net part 12.Wherein, Access Network part 11 mainly is made up of base station sub-system (BSS), and the UE that the base station transceiver (BTS) among the BSS is had jurisdiction over has formed a sub-district, and the base station controller of BSS (BSC) is responsible for communicating with core net part 12.Core net part 12 mainly comprises mobile switching centre (MSC), Visited Location Registor (VLR) and Group Call Register (GCR).

Fig. 2 is the structure chart of group system core net part.Referring to Fig. 2, below the various piece in the core net is illustrated respectively:

There is user profile in the attaching position register (HLR), comprises this user's international mobile subscriber knowledge sign indicating number (IMSI), the group ID tabulation of the affiliated group calling of this user.General, a user can belong to 50 groups at most.

GMSC (gateway mobile switching center) (GMSC) links to each other with external network, and GMSC also links to each other with the anchor mobile switching centre (Anchor MSC) of each group calling.

MSC is in charge of and safeguards a specific voice group call service (VGCS).

Relaying (Relay) MSC is when a group call region jumps a plurality of MSC, all MSC except that anchor MSC.It between anchor MSC and the relay MSC the tree-shaped relation of one-to-many.

Visited Location Registor (VLR) has the information such as group ID tabulation of user IMSI, the affiliated group calling of this user.When the user roamed, these information copied the VLR on the current ground of living in of user to from HLR.Simultaneously, the VLR lane place ID that also has connected MSC and had jurisdiction over.

Comprised group ID and group call region ID in the Group Call Register (GCR), group call region ID lumps together with group ID and is called group call reference information.Wherein with among the continuous GCR of anchor MSC comprised the routing iinformation relevant with this group call reference information, for example dispatching desk tabulation (dispatching desk can participate in conversation, and has the function of commander and scheduling group calling), relay MSC tabulation, the directly actuated cell list of anchor MSC.The GCR that links to each other with relay MSC has then comprised the routing iinformation relevant with this group call reference information, for example the cell list controlled of anchor MSC address, this relay MSC.

In the group system, the corresponding GCR of each MSC, GCR has write down some group call reference information and relevant routing iinformation thereof that this MSC supports, comprising determining group call region ID (GCA ID by group ID and sub-district ID, Group Call Area ID) information, this group call region id information is as shown in the following Table 1:

	Group ID i	Group ID j	……	Group ID k
	Group ID i	Group ID j	……	Group ID k	Sub-district ID n	GCA?ID?x
Sub-district ID m		GCA?ID?y			Sub-district ID n	GCA?ID?x
Sub-district ID m		GCA?ID?y			……		……
Sub-district ID l				GCA?ID?z	……		……

Table 1

As above shown in the table 1, wherein sub-district ID has comprised all sub-districts in this MSC district, and group ID has comprised all groups in local GCR registration.Also to routing iinformation that should group calling, if the anchor MSC that wherein local MSC is current GCA group calling that ID identifies, then the routing iinformation of GCA ID correspondence is dispatching desk tabulation, relay MSC tabulation, the directly actuated cell list of anchor MSC to each GCA ID; If local MSC is the relay MSC of current GCA group calling that ID identifies, then the routing iinformation of GCA ID correspondence is the cell list that anchor MSC address, this relay MSC are controlled.

For a group calling, may only have an anchor MSC, also may have an anchor MSC and at least one relay MSC.Fig. 3 realizes the anchor MSC of group calling and the tree type schematic diagram of relay MSC in the prior art.Referring to Fig. 3, main exhale user terminal (UE) by local sub-district BTS and the BSC among the BSS when the request of the MSC of locality initiation group calling, the group ID (Group ID) that is exhaled group is carried in this group calling request, after local MSC receives the group calling request, inquire about group call region id information table among the corresponding GCR of this MSC according to wherein group ID and the main sub-district ID (Cell ID) that exhales the UE place, be above-mentioned table 1, determine the main group call region ID at the present place of UE that exhales; Carry out paging then according to the routing iinformation of this group call region ID, and according to this routing iinformation from this GCR query call.Routing iinformation herein and corresponding group calling process thereof be in two kinds of situation:

One, local MSC is the anchor MSC of this group calling, then the address list of the routing iinformation that returns of the GCR dispatching desk address list that need connect for this group calling, relevant relay MSC and by the directly actuated cell address tabulation of this anchor MSC; In paging, anchor MSC is responsible for being established to being connected of described each sub-district, dispatching desk and relay MSC, set up the meeting bridge (be used for transporting speech) of group calling, and the cell paging under this anchor MSC control exhaled UE, promptly ordered the UE issuing page message of BTS in the sub-district of BSS under each sub-district; After relay MSC is received calling, inquire about the directly actuated cell address tabulation of this relay MSC to the GCR of its connection, UE is exhaled in paging in the sub-district of this relay MSC control; Exhaled in the process of UE at cell paging, the BTS of sub-district sends the beep-page message of this calling at notification channel (NCH) channel on the one hand, comprising and indicate its group-calling channel parameter (the group-calling channel parameter network be the wireless channel that this group calling distributes, specifically comprise frequency, information such as time slot and encryption key, exhaled UE to get final product this channel of demodulation as long as know these information) so that UE monitors in the group, and the group ID of this group calling or the number of being exhaled UE, the UE that is under the idle condition reads beep-page message from NCH, and judge whether to be self signatory group calling according to group ID wherein, perhaps exhale UE to judge whether self is exhaled UE according to quilt wherein, if, then select to add or do not add this group calling, and return page response to network side; On the other hand, BTS sends beep-page message at the descending FACCH channel of other group callings of having set up, the current UE that is participating in other group calling receives new group calling beep-page message at the descending FACCH channel of group calling, if also be the signatory group calling of oneself or self exhaled UE, then select to leave current group calling and add new group calling or continue to stay current group calling, and return page response to network side.

Two, local MSC is not the anchor MSC of this group calling, and then the routing iinformation that returns of GCR is the anchor MSC address of this group calling; Local MSC sends to anchor MSC with this group calling request, is responsible for finishing this group calling by anchor MSC, and the follow-up processing procedure of anchor MSC is identical with above-mentioned first kind of situation.

But, above-mentioned prior art scheme can only make the user in the defined group call region of cluster system to call group call reference information, if group calling UE leaves the group call region of its affiliated group calling, when being the UE roaming, then this UE does not receive the beep-page message of this group calling in current area, so can't be as being exhaled UE to participate in group calling; In addition, if the master exhales UE to be in the roaming place of current group calling, after the master exhales the call request of UE reporting group call, because the GCA ID of this UE not registration correspondence on the GCR of roaming place, therefore local MSC can't find corresponding GCA ID when GCR inquires about above-mentioned table 1, can refuse the group calling request that this master exhales UE at last, therefore, roaming UE can not initiatively initiate group calling in the roaming place, the roaming position district that network can recording user yet.

Summary of the invention

In view of this, main purpose of the present invention is to provide a kind of roaming implementation method of group calling, participates in group calling to realize the cluster user terminal at random zone.

A kind of roaming implementation method of group calling, this method comprises:

A, user terminal monitor its belonging positions district and change and then report the roaming updating message of carrying its signatory group calling group ID to local moving exchanging center MSC;

After B, local MSC receive this roaming updating message, judge according to the group call reference information of preserving among the local Group Call Register GCR whether the lane place that user terminal ought advance into is the roaming place of the group group calling that ID identified in this message, if, then obtain this location area information, this lane place is preserved as the temporary group calling zone of this group calling at network side.

Preferably, described local MSC, according to the group call reference information of preserving among the local GCR judge user terminal when the lane place that advance into whether be that the method for the roaming place of the described group of group calling that ID identified is:

Inquire about the group call reference information of preserving among the local GCR, judge whether to have group call reference information by described group calling ID and described lane place corresponding stored, if no, judge that then it is the roaming place of the described group of group calling that ID identified that user terminal is worked as the lane place that advances into.

Preferably, among the step B, described local MSC further comprises after receiving the roaming updating message: local MSC checks that it is to enter local MSC district from other MSC districts that the lane place of user terminal changes, and still changes between the lane place in local MSC district;

If user terminal is when the roaming place of the lane place that advances into for its signatory group calling, and it is to enter local MSC district from other MSC districts that the lane place of user terminal changes, then local MSC is except carrying out described this location area information of obtaining, outside the step that this lane place is preserved as the temporary group calling zone of described group calling, also further inquire about the anchor MSC address of the described group calling that sets in advance on the HLR, with of the temporary group calling zone corresponding preservation of this anchor MSC address with described group calling, the address of local MSC is sent to this anchor MSC, and preserve as the interim relay MSC address of described group calling the address that anchor MSC should locality MSC;

If user terminal changes between the lane place that advance into for the lane place of the roaming place of its signatory group calling and user terminal changes is lane place in local MSC district, then only carry out described this location area information of obtaining, the step that this lane place is preserved as the temporary group calling zone of described group calling.

It is to enter local MSC district from other MSC districts that the lane place of described inspection user terminal changes, still the method that changes between the lane place local MSC district in is: whether record the information of this user terminal among the Visited Location Registor VLR of local MSC inquiry locality, if not then judge that the variation of user terminal location district is to enter local MSC district from other MSC districts; Otherwise, judge that it is to change between the lane place in local MSC district that the user terminal location district changes.

The roaming implementation method of described group calling further comprises: whether local MSC monitor user ' terminal leaves the lane place as the temporary group calling zone of described group calling, if then delete this temporary group calling area information.

Local MSC is at the described user terminal of described lane place timing paging, the described user terminal of paging when perhaps running into group calling; Judge whether to receive the page response of user terminal,, judge that then this user terminal does not leave this lane place if receive; Otherwise, judge that this user terminal has left this lane place.

The roaming implementation method of described group calling further comprises:

Whether local MSC monitor user ' terminal leaves local MSC district, if, then notify described anchor MSC deletion should locality MSC as the record of the interim relay MSC of described group calling, the anchor MSC address of the described group calling of deleting local MSC simultaneously and being preserved and the temporary group calling area information of described group calling.

The method whether described local MSC monitor user ' terminal leaves local MSC district is:

Local MSC is this user terminal of timing paging in all temporary group calling zones of this user terminal, the described user terminal of paging when perhaps running into group calling; Judge whether to receive the page response of user terminal,, judge that then this user terminal does not leave local MSC district if receive; Otherwise, judge that this user terminal has left local MSC district.

Described user terminal is monitored the method that its belonging positions district changes: network side is broadcasted each location area information, and whether the location area information that user terminal is received by judgement changes is determined whether its belonging positions district changes.

The method that described local MSC obtains location area information is: the identification information according to the user terminal that carries in the described roaming updating message is inquired about local VLR, obtains this user terminal present located location area information.

The number of the signatory group calling group ID that carries in the described roaming updating message is at least one; Network side all carries out the processing of step B to each group group calling that ID identified.

Because method of the present invention is when user terminal moves to the roaming place of group calling, network side is preserved the current belonging positions of portable terminal district as the temporary group calling zone of this group calling, when initiating group calling, if portable terminal is caller, owing to, therefore can finish group calling from the temporary group calling zone that local MSC can find this group calling; If user terminal is called,, therefore also can finish group calling because local MSC can carry out paging to user terminal in the temporary group calling zone.Therefore, the present invention can realize that the cluster user terminal is at random zone initiation group calling and reception group calling.

The present invention strides the MSC district when moving into the roaming place of group calling at user terminal, not only the current belonging positions of portable terminal district is preserved as the temporary group calling zone of this group calling, but also with the interim relay MSC of local MSC as this group calling, so just expanded the routing iinformation when user terminal is in the roaming place, be the tree relation of anchor MSC and relay MSC, make user terminal can realize the roaming of group calling when mobile equally striding the MSC district.

Description of drawings

Fig. 1 is the structure chart of current cluster system;

Fig. 2 is the structure chart of group system core net part;

Fig. 3 realizes the anchor MSC of group calling and the tree type schematic diagram of relay MSC in the prior art;

Fig. 4 is the zone definitions figure of existing group system;

Fig. 5 is the flow chart of the roaming implementation method of group calling of the present invention;

Fig. 6 group calling is realized the tree schematic diagram of roaming back anchor MSC and relay MSC.

Embodiment

Below by specific embodiments and the drawings the present invention is described in further details.

Fig. 4 is the zone definitions figure of existing group system.Referring to Fig. 4, distinguish different service areas according to the size of service area scope.Wherein scope minimum service district is the sub-district; Big slightly service area is a base station overlay area, can comprise some each sub-districts; Bigger again is the lane place, a lane place can be made up of at least one base station overlay area, the lane place is the maximum service district that user terminal can be discerned, network side can send the broadcast message of lane place periodically, when user terminal when mobile, can judge whether the lane place at its current place changes according to the lane place broadcast message of network side; The service area bigger again than the lane place is the MSC district, administered by MSC; Maximum service area is Public Land Mobile Nerwork (PLMN) district.

Fig. 5 is the flow chart of the roaming implementation method of group calling of the present invention.Referring to Fig. 5, this flow process comprises:

Step 501, user terminal are in the process that moves, can receive the location area information of network side broadcasting, whenever user terminal changes according to location area information judgement self present located lane place, then this user terminal comprises in this roaming updating message to local MSC report of user roaming updating message: show that this message is the type identification field of roaming updating message, the identification information of user terminal, group ID and the number of group ID and the information of size that this user will upgrade group calling.

User terminal receives location area information at every turn and all can preserve, as long as original location area information of preserving with self when the location area information of receiving is different, then user terminal judgement self present located lane place changes, and replaces the location area information of original preservation after finding to change at once with new location area information.

The group ID that comprises in the described roaming updating message wishes to upgrade the group calling area information so that realize the group ID of roaming at network side for all user terminals, and these groups ID may be the group ID of the part group in all signatory group callings of this user.User terminal can receive user's manual command, and the group ID in this roaming updating message manually is provided with; Also can automatic setting be set by man-machine interface (MMI), for example the group of all under user terminal ID is set to the form preservation of telephone directory, and give an attribute i.e. " each location area updating reports the roaming updating message " to each group ID that need upgrade, after user terminal judged that at every turn the position is upgraded, the group ID that will have this attribute automatically was carried in the roaming updating message and reports.The group ID that comprises in the described roaming updating message normally user's frequency of utilization the highest or some groups of paying close attention to.The group calling that does not comprise in the roaming updating message for reporting of user, then network side is not supported the roaming of user in these groups, comprises initiating caller and called.

Step 502, the current affiliated MSC of user terminal, be local MSC, the message of user terminal is received in parsing, in case the type identification that is resolved to is the roaming updating message, judge then whether this user terminal arrives a new MSC district, the lane place that is user terminal changes whether enter local MSC district from other MSC districts, if user terminal has arrived a new MSC district, execution in step 503; Otherwise the lane place that shows user terminal change to be to change between the lane place in local MSC district, execution in step 508.

In this step 502, because those of ordinary skills know: user terminal sends any message to network side, comprise above-mentioned roaming updating message, must set up RRC with the local networks side is connected, after setting up RRC, local MSC has obtained the identify label of user terminal, for example temporary mobile subscriber identity (TMSI) or international mobile subscriber are known sign indicating number (IMSI), local MSC receives the roaming updating message of user terminal, local VLR is inquired about in identify label according to this user terminal that obtains, judge the information of whether having preserved this user terminal among the VLR, if preservation is arranged, judge that then this user terminal does not arrive a new MSC district, promptly the lane place of user terminal change to be to change between the lane place in local MSC district; Otherwise, judge that this user terminal has arrived a new MSC district, need the identification information of this user terminal of storage this moment, whether leave this MSC district to be used for this user terminal of follow-up monitoring.

Step 503, described local MSC parse the group ID in the described roaming updating message, and ID begins to handle from first group,

Step 504, this locality MSC inquire about in the group call reference information among the connected local GCR whether identical group ID record is arranged, if have, then execution in step 506, illustrate that the roaming place of user terminal supports identical group ID number this moment, roaming user terminal can be initiated group calling, but the called of calling is local user terminal, and this situation also can be received beep-page message simultaneously, but is the call information of roaming place Local Local User Terminal; If there is not identical group ID record, then judge and do not have described group of ID and the corresponding group call reference information of forming of user terminal present position-region among the local MSC, simultaneously judge that in view of the above active user's terminal enters into the roaming place of the described group of group calling that ID identified, execution in step 505.

Step 505, the described lane place of active user's terminal is preserved as the temporary group calling zone of the described group of group calling that ID identified, promptly add current group of ID, the corresponding group call reference information of forming in active user's terminal position district in local GCR, its form is included sub-district ID in current group of ID, active user's terminal position district and the mapping table of group call region ID; Wherein, active user's terminal position district ID with and all sub-district ID of comprising obtain according to inquiry VLR by local MSC, group call region ID is the interim group call region ID that gets, in case user terminal leaves present position-region, then the group call region ID with this lane place correspondence deletes.Described corresponding relation is referring to following table 2:

Table 2

As shown in table 2, under roaming condition, for same group of ID, the temporary group calling area I D of all sub-districts is identical in lane place.

This moment, local MSC need notify the anchor MSC active user of current group calling to be in local MSC to have jurisdiction in the lane place.In order to reach this purpose, the anchor MSC address of the present invention's each group calling that the preservation user terminal is contracted in HLR in advance; And the roaming sign of each group calling that user terminal contracts is set in HLR, the number of this roaming sign equals the group calling number that user terminal is contracted, and corresponding respectively group calling separately, i.e. only corresponding group calling of roaming sign, and with two kinds of current roaming states that in this group calling, whether are in of different state representation user terminals, for example " 0 " represents non-roaming state, " 1 " expression roaming state.User terminal is in different group callings, and its situation about whether roaming is also different, must not mentionlet alone brightly with each component, just knows whether present this user is in the roaming place in this group calling as long as MSC checks this sign.For each group calling, all have corresponding group call region, if user terminal present located zone does not belong to the group call region of this group calling, then for this group calling, this user terminal is in roaming state.

In this step 505, local MSC visit HLR inquires about the address of the anchor MSC of current group calling according to the group ID of current group calling, and after HLR returned Query Result, local MSC preserved the address of this anchor MSC, and with current group the corresponding preservation of temporary group calling area I D.And to this anchor MSC transmission routing update message, the address of carrying group ID He this locality MSC of current group calling in this routing update message; After anchor MSC receives this routing update message, visit connected GCR, upgrade the routing iinformation of this group ID correspondence, be about to MSC address, this locality and preserve as an interim relay MSC address of this group calling.

Step 506～step 507, local MSC judge whether the group ID in the described roaming updating message all disposes, if, process ends then; Otherwise, begin next one group ID is handled, return step 504.

Step 508, described local MSC parse the group ID in the described roaming updating message, and ID begins to handle from first group.

Step 509, local MSC visit local VLR, whether the group call region of inquiring about in the pairing group call reference information of current group calling ID comprises the current affiliated lane place of user terminal fully, promptly judge whether to have group call reference information by described group calling ID and described lane place corresponding stored, if have, judge that then it is not the roaming place of the described group of group calling that ID identified that user terminal is worked as the lane place that advances into, then execution in step 511; Otherwise, judge that it is the roaming place of the described group of group calling that ID identified that user terminal is worked as the lane place that advances into, execution in step 510.

Step 510, because the residing local MSC of active user's terminal district does not change, therefore with GCR that this locality MSC is connected on preserved certainly this user terminal the group ID of signatory group calling, and should locality MSC be the anchor MSC or the relay MSC of the signatory group calling of user terminal at this moment certainly, therefore only need on local GCR, to upgrade the location area information of current group calling correspondence this moment, be about to roam the lane place ID that carries in the updating message temporary group calling area part and the corresponding preservation of group ID as current group calling, as the group call reference information of this group calling, also soon this lane place ID adds in the group call region tabulation of this group ID correspondence.

Step 511～step 512, local MSC judge whether the group ID in the described trip updating message all disposes, if, process ends then; Otherwise, begin next one group ID is handled, return step 509.

The described embodiment of Fig. 5 participates in the purpose of calling out when realizing that the cluster user terminal is roamed between different MS C district.

Certainly, participate in the purpose of calling when roaming in this MSC of user terminal district in order to be implemented in, the present invention also can remove above-mentioned steps 502, and step 501 back is execution in step 508 and its subsequent step directly.

Through after the above-mentioned flow processing, for a group calling, the anchor MSC of its original realization group calling and the tree of relay MSC can change.Fig. 6 group calling is realized the tree schematic diagram of roaming back anchor MSC and relay MSC.Referring to Fig. 6, roam into the reposition district 61 of a certain group calling when user terminal after, the information of this lane place 61 is stored among the GCR of MSC under it by above-mentioned flow processing, MSC is the new relay MSC 62 of this group calling under it, and this relay MSC 62 is interim relay MSC, add the address of the anchor MSC that preserves this group calling in this relay MSC, and on the anchor MSC address of this group calling, add the address of this newly-increased relay MSC 62.By processing of the present invention, when user terminal was in the roaming position district of group calling, variation had taken place in the anchor MSC of this group calling and the tree of relay MSC, added and had advanced new routing iinformation, i.e. dotted line identification division among Fig. 6.

MSC when the roaming place, promptly the MSC62 among Fig. 6 monitors user terminal and leaves this MSC district, then deletes the routing iinformation that is added.Concrete implementation method is:

Roaming place MSC reads the described user terminal identification information of being preserved, according to the described user terminal of timing paging in all temporary group calling zones of the user terminal of this identification information in local MSC, the described user terminal of paging when perhaps running into group calling; And judge whether to receive the page response of user terminal, if receive, judge that then this user terminal does not also leave this MSC district; Otherwise, judge that this user terminal has left this MSC district.

The routing iinformation that described deletion is added comprises: local MSC notice anchor MSC deletes the address record of this locality MSC as interim relay MSC; All temporary group calling area I D information relevant and corresponding anchor MSC address that local MSC notifies local GCR deletion to be preserved with this user terminal.

When user terminal was just roamed between the lane place at local MSC, whether then local MSC monitor user ' terminal left the lane place as the temporary group calling zone of described group calling, if then delete this temporary group calling area information.

The method whether described monitor user ' terminal is left as the lane place in described group calling temporary group calling zone is: local MSC is at the described user terminal of described lane place timing paging, the described user terminal of paging when perhaps running into group calling; Judge whether to receive the page response of user terminal,, judge that then this user terminal does not leave this lane place if receive; Otherwise, judge that this user terminal has left this lane place.

By method of the present invention, when user terminal is in the roaming district of a certain group calling, current present position district id information is kept on the local GCR as group call reference information, and with the relay MSC of local MSC as this group calling.Therefore, in case this moment, this user terminal was initiated the group calling request, local MSC can find the group call region ID in its corresponding group call reference information, therefore can further the group calling request be sent to anchor MSC, and finish group calling with existing group calling flow process.

In case another user terminal of described group calling is initiated group calling, then anchor MSC also can send to beep-page message local MSC, because should locality MSC have become a relay MSC of this group calling this moment, local MSC carries out paging to roaming user terminal again, thereby realizes being exhaled this roaming user terminal.

The above; only for the preferable embodiment of the present invention, but protection scope of the present invention is not limited thereto, and anyly is familiar with the people of this technology in the disclosed technical scope of the present invention; the variation that can expect easily or replacement all should be encompassed within protection scope of the present invention.

Claims

1, a kind of roaming implementation method of group calling is characterized in that, this method comprises:

2, the roaming implementation method of group calling according to claim 1, it is characterized in that, described local MSC according to the group call reference information of preserving among the local GCR judge user terminal when the lane place that advance into whether be that the method for the roaming place of the described group of group calling that ID identified is:

3, the roaming implementation method of group calling according to claim 1 is characterized in that:

Among the step B, described local MSC further comprises after receiving the roaming updating message: local MSC checks that it is to enter local MSC district from other MSC districts that the lane place of user terminal changes, and still changes between the lane place in local MSC district;

If user terminal is when the roaming place of the lane place that advances into for its signatory group calling, and it is to enter local MSC district from other MSC districts that the lane place of user terminal changes, then local MSC is except carrying out described this location area information of obtaining, outside the step that this lane place is preserved as the temporary group calling zone of described group calling, also further inquire about the anchor MSC address of the described group calling that sets in advance on the attaching position register HLR, with of the temporary group calling zone corresponding preservation of this anchor MSC address with described group calling, the address of local MSC is sent to this anchor MSC, and preserve as the interim relay MSC address of described group calling the address that anchor MSC should locality MSC;

4, the roaming implementation method of group calling according to claim 3 is characterized in that:

5, according to the roaming implementation method of claim 1 or 3 described group callings, it is characterized in that, this method further comprises: whether local MSC monitor user ' terminal leaves the lane place as the temporary group calling zone of described group calling, if then delete this temporary group calling area information.

6, the roaming implementation method of group calling according to claim 5 is characterized in that, the method whether described monitor user ' terminal is left as the lane place in described group calling temporary group calling zone is:

7, the roaming implementation method of group calling according to claim 3 is characterized in that, this method further comprises:

8, the roaming implementation method of group calling according to claim 7 is characterized in that, the method whether described local MSC monitor user ' terminal leaves local MSC district is:

9, the roaming implementation method of group calling according to claim 1 is characterized in that:

10, the roaming implementation method of group calling according to claim 1, it is characterized in that: the method that described local MSC obtains location area information is: the identification information according to the user terminal that carries in the described roaming updating message is inquired about local VLR, obtains this user terminal present located location area information.

11, the roaming implementation method of group calling according to claim 1 is characterized in that: the number of the signatory group calling group ID that carries in the described roaming updating message is at least one; Network side all carries out the processing of step B to each group group calling that ID identified.