WO2012044109A2

WO2012044109A2 - Group communication method and apparatus

Info

Publication number: WO2012044109A2
Application number: PCT/KR2011/007230
Authority: WO
Inventors: 김성경; 장성철; 김은경; 이현; 윤철식
Original assignee: 한국전자통신연구원
Priority date: 2010-09-30
Filing date: 2011-09-30
Publication date: 2012-04-05
Also published as: WO2012044109A3

Abstract

Provided is a group communication method for a terminal. A terminal establishes a group call connection with a first base station which belongs to a group call area, and receives group call data from the first base station. When the terminal moves into the coverage of a second base station which belongs to the group call area, the terminal receives group call data from the second base station, without re-registration in the second base station.

Description

Group communication method and apparatus

The present invention relates to a group communication method and apparatus.

Since a group communication service in which a plurality of users participates in a call transmits the same downlink traffic to all users in the group at the same time, downlink multicast or broadcast based communication connection may be used as well as a unicast connection. Therefore, when using a group communication service in a cellular-based wireless access system, it is possible to consider existing broadcast service technologies such as multicast broadcast service (MBS) technology or terminal-based unicast service technology. .

Since the prior art is designed for a unicast service terminal or a broadcast service terminal, it is inefficient when the prior art idle mode method is applied to a group communication terminal. In particular, when the number of users currently participating in group communication is large, and most of the users participate in the service for the purpose of listening, uplink traffic may be limited to some specific users. In addition, group communication, such as push-to-talk (PTT), can have a very long call duration, unlike a one-to-one voice service in a general public network, and a long period of inactivity of voice traffic. Therefore, when users are scattered and moved across cells, unnecessary handovers are performed to maintain bidirectional connection setup even if no group communication traffic occurs. In addition, since the base station maintains unnecessary connection settings and continuously manages information of each terminal, efficiency decreases and power consumption of the terminal increases.

An embodiment of the present invention is to provide a group communication method and apparatus capable of performing an idle mode operation suitable for group communication.

According to an embodiment of the present invention, a group communication method of a terminal is provided. The group communication method may include: establishing a group call connection with a first base station belonging to a group call area, receiving group call data from the first base station, and moving to an area of a second base station belonging to the group call area And receiving group call data from the second base station without re-registering with the second base station.

The group communication terminal may further include receiving a group ID for a group call in the group call region from the first base station. In this case, the terminal may use the group ID in the second base station.

Receiving group call data from the first base station may include entering a dormant mode, and receiving group call data from the first base station in the dormant mode.

The step of entering the idle mode may include receiving a deregistration request message and a deregistration response message for the deregistration request message.

Moving to the area of the second base station may include moving to the area of the second base station in the idle mode.

Receiving group call data from the second base station may include receiving group call data from the second base station in the idle mode.

The group communication method may further include: entering a dormant mode, moving from a dormant mode to a third base station not belonging to the group call area, receiving broadcast information from the third base station, and from the broadcast information; The method may further include obtaining group call information of a group call region to which the third base station belongs.

The group communication method may further include receiving broadcast information including group call information from a third base station, and recognizing that the group call is out of the group call area based on the broadcast information.

In a group communication method of a terminal according to another embodiment of the present invention, the method includes: establishing a group call connection with a first base station, receiving group call data from the first base station, entering a dormant mode, and performing the idle Receiving group call data from the first base station in mode.

Entering the idle mode may include receiving a deregistration request message and a deregistration response message for the deregistration request message.

The group communication method further includes moving to a second base station belonging to the same group call area as the first base station, and receiving group call data from the second base station without re-registering with the second base station. can do.

The group communication method may include: moving to a second base station belonging to a group call area different from the first base station, receiving broadcast information from the second base station, and group call to which the second base station belongs from the broadcast information. The method may further include obtaining group call information of the region.

The group communication method may further include performing a location update with a second base station of the changed group call area when the group call area is changed in the idle mode.

The performing of the location update may include receiving information on the changed group call region from the second base station in a unicast manner.

According to another embodiment of the present invention, a terminal including a controller and a receiver is provided. The controller establishes a group call connection with a first base station belonging to a group call area. The receiving unit receives group call data from the first base station, and receives group call data from the second base station without re-registering with the second base station when moving to the area of the second base station belonging to the group call area. do.

The controller may be allocated a group ID for a group call in the group call region from the first base station and use the group ID in the second base station.

The terminal may further include a idle mode controller for entering a idle mode. In this case, the receiver may receive group call data from the first base station in the idle mode.

According to an embodiment of the present invention, even if the terminal moves to another base station by the group call area, the group call service may be continuously provided.

Even if the terminal receiving the group call according to another embodiment of the present invention enters the idle mode, the group call service may be continuously provided.

1 to 4 are diagrams each illustrating a group communication system according to an embodiment of the present invention.

5 to 7 are diagrams each illustrating a group communication method in a group communication system according to an embodiment of the present invention.

8 is a block diagram of a group communication device according to an embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, a terminal may be a mobile terminal (MT), a mobile station (MS), an advanced mobile station (AMS), a high reliability mobile station (HR-MS). May also refer to a subscriber station (SS), a portable subscriber station (PSS), an access terminal (AT), a user equipment (UE), and the like. It may also include all or part of the functionality of the HR-MS, SS, PSS, AT, UE and the like.

In addition, the base station (BS) may be an advanced base station (ABS), a high reliability base station (HR-BS), a node B (node B), an advanced node B (evolved node B, eNodeB), access point (AP), radio access station (RAS), base transceiver station (BTS), mobile multihop relay (MMR) -BS, relay serving as a base station station, RS), a high reliability relay (HR-RS) serving as a base station, etc., and may also refer to ABS, Node B, eNodeB, AP, RAS, BTS, MMR-BS, RS, HR. It may include all or part of functions such as -RS.

Referring to FIG. 1, traffic is transmitted from a predetermined node 110 to at least one

base station

121, 122 for group communication. The predetermined node may be an upper node such as a group call server 110, for example, a PTT server. In this case, the PTT server 110 and the

base stations

121 and 122 may be connected through a router (not shown), a control station (not shown), or the like. The base station (121, 122) establishes a group call connection in the radio access section, and transmits the traffic to the terminals (131-134, 135-138) belonging to its own area among the user group 130 in a multicast manner.

2 to 4, the group communication system may be classified into three types according to the operation method of the base station.

The group communication system shown in FIG. 2 uses a single base station group call service. Each base station manages a terminal belonging to its own cell area for a group call for group communication. Accordingly, even if a plurality of terminals belong to the same user group, a group identifier (ID) is assigned according to a cell to which the terminal belongs. That is, the group ID for identifying the group call is unique only in the corresponding base station. The group call connectivity of the terminal is limited to the serving base station, and the terminal resets the connection to the group call at the target base station at the time of handover and receives a group ID.

The group communication system shown in FIG. 3 uses a macro BS group call service. A group call zone is defined across a plurality of base stations, and connection settings for the group call are managed within the group call zone. Accordingly, the group ID for identifying the group call is unique in the same group call area. That is, a unique group ID is assigned to each group call area. In the macro base station group call service, a group call service is provided in a corresponding cell regardless of the presence or absence of a group call terminal in an active state in the base station.

In this case, the group call area may be dynamically defined around the area where group communication occurs, and may be identified by the group call area ID. The information on the group call area may be determined during the group call setup process or may be determined in advance in the user group configuration step for the group call. The same group call setup can also be made across multiple group call regions. If the group call area is different, the group call connection setup information and the resource allocation for the group call may be different.

The group communication system illustrated in FIG. 4 uses an MS-positioned group call service. The group communication system of FIG. 4 is similar to the group communication system shown in FIG. 3 in that a plurality of base stations share a group call connection setup, but is a base station in a cell area in which terminals of a user group are in an active state. There is a difference in providing a group call service by forming a group call area using only these two groups. Therefore, a unique group ID is given for each service.

Meanwhile, the group communication system described with reference to FIGS. 3 and 4 may further include a controller for managing the group call area and the group ID. Such a controller may be mounted in the group call server 110 (in FIG. 1) or may be constructed as a separate server.

Next, a group communication method of a terminal in a group communication system in which a group call area is defined will be described with reference to FIGS. 5 to 7.

Referring to FIG. 5, a terminal 10 belonging to a user group for group communication first establishes a group call connection, that is, a multicast connection, with the serving base station 21 (S510). The terminal 10 continuously receives the group call data through the serving base station (S520). At this time, the base station 21 transmits the group call data to the terminal of the user group belonging to its area in a multicast manner.

In this way, while receiving the group call data, the terminal 10 may enter the idle mode (S530). For example, if there is no data to be transmitted for a certain period or if there is no connection setting other than the group call, the terminal 10 may enter a dormant mode. In order to enter the idle mode, the terminal 10 and the serving base station 21 deregistration request (DREG-REQ) message for the unicast connection establishment and the deregistration response (DREG-REQ) -RSP) messages can be exchanged. In the idle mode, the terminal 10 periodically repeats a paging listening interval and a paging unavailable interval. In addition, the terminal 10 may receive the group call data in the group call area through the multicast connection for the group call even in the idle mode (S540).

When the next terminal 10 moves from the base station 21 to another base station 22 belonging to the same group call area as the base station 21 (S550), since the two

base stations

21 and 22 belong to the same group call area, the terminal 10 continuously receives the group call data through the base station 22 without changing the group call connection setting information (S560). That is, the terminal 10 can continuously receive the group call data without having to re-register with the base station 22.

Meanwhile, as shown in FIG. 5, while the terminal 10 receives the group call service in the idle mode, the group call area to which the terminal 10 belongs may be changed. In this case, the terminal 10 receives broadcast information broadcast from the base station 23 belonging to the changed group call region as shown in FIG. 6 (S610), and recognizes the change of the group call region through the received broadcast information ( S620). The broadcast information may include group call information, and the group call information may include a group call area ID and a group ID. The terminal 10 recognizes the change in the group call area and acquires wireless connection information of the group call such as a group ID corresponding to the group call to be serviced (S630). Accordingly, the terminal 10 continuously receives the group call data from the base station 23 (S640). When the group call area is changed, the terminal 10 may perform location update on the corresponding group call area. In this case, the terminal 10 and the base station 23 may exchange the group call information of the group call region changed during the location update process in a unicast manner.

Next, referring to FIG. 7, after the terminal 10 receives a group call service by establishing a group call connection with the base station 21 after entering the idle mode (S710, S720, S730, and S740), The base station 21 may move out of the group call area to which the base station 21 belongs to another base station 24 (7650). The terminal 10 receives broadcast information periodically broadcasted from the base station 24 (S760). Such broadcast information may include group call information, and the group call information may include a group call area ID and a group ID. The terminal 10 obtains the group call information of the group call area to which the base station 24 belongs from the broadcast information. If there is no information on the group call received in the broadcast information, the terminal 10 ends the idle mode and enters the network into the base station 230. Perform the procedure (S670). The terminal 10 may perform a network entry procedure by exchanging a ranging request (RNG-REQ) message and a ranging response (RNG-RSP) message with the base station 24. Thereafter, the terminal 10 performs group call connection establishment with the base station 230 (S680), and receives a group call service again (S690). At this time, the base station 24 may be included in the group call area and operated through information exchange with the controller managing the group call area, or may maintain a separate group call connection setting.

As described above, according to an embodiment of the present invention, even if the UE moves to another base station by the group call area, the group call service can be continuously provided, and the group call service is performed even when the UE receiving the group call enters the idle mode. You can continue to receive.

Meanwhile, if the group call data is absent for a certain period after the UE enters the idle mode, the group call connection may be deregistered. In this case, when group call data is generated, the base station may simultaneously page terminals belonging to a user group with a multicast paging message. In order to page a user group, the base station may use a multicast deregistration ID (DID) or a group ID previously assigned to the user group. By using a multicast paging message, it is possible to prevent an overload of paging signaling that may occur when paging a plurality of terminals of a user group, and thus delay group call setup.

In addition, when the terminal of the user group enters the network according to paging, the network entry priority may be differentiated according to the class of the terminal in order to control excessive delay and collision due to the ranging procedure. Alternatively, a terminal group that does not need to check the existence of the terminal when establishing a group call may start a group communication service in a listening mode without a network entry procedure. Such a terminal may attempt network entry at a point where an uplink connection setting is required or when network entry overload is eliminated.

Next, a group communication apparatus for performing a group communication method according to an embodiment of the present invention will be described in detail with reference to FIG. 8.

Referring to FIG. 8, the group communication device 800 includes a controller 810, a receiver 820, and an idle mode controller 830. The group communication device 800 may be formed in the terminal 10 or may be the terminal 10 itself.

The receiver 820 receives group call data and broadcast information transmitted from the base station as described with reference to FIGS. 5 to 7.

As described with reference to FIGS. 5 to 7, the controller 810 establishes a group call connection with the base station, and checks whether the base station currently belonging to the current group call area based on broadcast information when moving. In addition, the control unit 810 is assigned a group ID from the base station, and uses the same group ID assigned in the same group call area.

The idle mode controller 830 controls the operation of the terminal 10 in the idle mode as described with reference to FIGS. 5 to 7.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims

As a group communication method of a terminal,

Establishing a group call connection with a first base station belonging to a group call area;

Receiving group call data from the first base station,

Moving to an area of a second base station belonging to the group call area, and

Receiving group call data from the second base station without re-registering with the second base station

Group communication method comprising a.
In claim 1,

Receiving from the first base station a group ID for a group call in the group call region;

The terminal uses the group ID in the second base station.

Group communication method.
In claim 1,

Receiving the group call data from the first base station,

Entering idle mode, and

Receiving group call data from the first base station in the idle mode

Group communication method comprising a.
In claim 3,

The step of entering the dormant mode may include receiving a deregistration request message and a deregistration response message for the deregistration request message with the first base station.
In claim 1,

Moving to the area of the second base station comprises moving to the area of the second base station in an idle mode.
In claim 5,

Receiving group call data from the second base station comprises receiving group call data from the second base station in the dormant mode.
In claim 1,

Entering idle mode,

Moving to a third base station not belonging to the group call area in the idle mode;

Receiving broadcast information from the third base station, and

Acquiring group call information of a group call region to which the third base station belongs from the broadcast information;

Group communication method further comprising.
In claim 1,

Receiving broadcast information including group call information from a third base station, and

Recognizing that the group call area is out of the group based on the broadcast information

Group communication method further comprising.
As a group communication method of a terminal,

Establishing a group call connection with the first base station,

Receiving group call data from the first base station,

Entering idle mode, and

Receiving group call data from the first base station in the idle mode

Group communication method comprising a.
In claim 9,

The step of entering the idle mode includes receiving a deregistration request message with the base station and a deregistration response message for the deregistration request message.
In claim 9,

Moving to a second base station belonging to the same group call region as the first base station, and

Receiving group call data from the second base station without re-registering with the second base station

Group communication method further comprising.
In claim 9,

Moving to a second base station belonging to a group call region different from the first base station,

Receiving broadcast information from the second base station, and

Acquiring group call information of a group call region to which the second base station belongs from the broadcast information;

Group communication method further comprising.
In claim 9,

If the group call area is changed in the idle mode, performing a location update with a second base station of the changed group call area.
In claim 13,

The performing of the location update includes receiving information on the changed group call area from the second base station in a unicast manner.
A control unit for establishing a group call connection with a first base station belonging to a group call area, and

A receiver that receives group call data from the first base station and receives group call data from the second base station without re-registering with the second base station when moving to the area of the second base station belonging to the group call area.

Group communication device comprising a.
The method of claim 15,

The control unit is assigned a group ID for a group call in the group call area from the first base station, and the second base station also uses the group ID.
The method of claim 15,

Further comprising a idle mode control unit for entering the idle mode,

The receiving unit receives group call data from the first base station in the idle mode.

Group communication device.