JP2009284127A - Group speech system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out a group speech between networks which use different communication systems, and to provide a group speech system that improves convenience. <P>SOLUTION: The group speech system connects a press talk control server 1 of an "A" network and LCU (Line Control Unit) 5 of a "B" network, while it performs communication by a protocol in the "A" network with the press talk server, and performs communication by a protocol in the "B" network with the LCU 5, it includes a LCU proxy server 4 which performs "protocol conversion" associated with the communication between the press talk control server 1 and the LCU 5, and the press talk control server 1 transceives control data of group communication with the LCU 5 through the LCU proxy server 4, and controls group communication between a terminal 3 of the "A" network and a terminal 7 of the "B" network. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a group call system using wireless portable terminals, and more particularly to a group call system that enables group calls between networks having different communication methods.

2. Description of the Related Art Conventionally, there is a method using PoC (Push-to-Talk over Cellular) as a method for performing a group call by half-duplex many-to-many broadcast communication between a plurality of wireless portable terminals on an IP network.
In PoC, a portable terminal can be used like a transceiver, and when a button is pressed, a voice is transmitted to the other party. If group members are registered in advance, a plurality of members can be simultaneously registered as in a conference call. It is transmitted to the terminal, and a plurality of terminals receive the voice. The method of sending a message by pressing a button is called press talk.

In a system for making a group call using PoC, whether the group call control server starts a group call in response to a request from the terminal and whether or not permission is allowed when a request for transmission is received from the terminal during the call The transmission right is controlled by permitting the terminal to transmit the transmission right and releasing the transmission right when a transmission right release request is received from the terminal.
In addition, there is one that realizes a group call using another communication method, for example, on an ISDN network instead of an IP network.

[Prior art documents]
As a prior art related to a system for making a group call using PoC, “PushTalk service system development, NTT DoCoMo Technical Journal Vol.13 No.4, P6-13” is available.

PushTalk service system development, NTT DoCoMo Technical Journal Vol. 13 No. 4, P6-13

  However, the conventional group call system using PoC has a problem that it is inconvenient because a group call cannot be performed with a terminal of another network not using PoC.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a group call system that enables group calls between networks using different communication methods and can improve convenience. .

  The present invention for solving the problems of the above-described conventional example includes a press talk control server for controlling a group call in a first network that realizes a group call by press talk using a specific communication method, and a specific communication method. A group call system having a line control device for controlling a group call in a second network that realizes a group call using a press talk other than the above, wherein the press talk control server is connected to the line control device, and the press talk control server A proxy that communicates with the protocol in the first network, communicates with the line control device with the protocol in the second network, and performs protocol conversion associated with communication between the press talk control server and the line control device Server, and the press talk control server is a proxy server The group call control data is transmitted / received to / from the line control device via the network, the group call between the terminal included in the first network and the terminal included in the second network is controlled, and the group call is in progress In addition, when there is a transmission right acquisition request from a terminal included in the first network, the line connection device is requested to acquire the transmission right through the proxy server, and the transmission right is requested from the line connection device through the proxy server. If the transmission right is not acquired in the network of No. 2, the transmission right is granted to the requesting terminal, and if there is a transmission right acquisition request from the line connection device via the proxy server, the first It is characterized in that control is performed so that a transmission right is not given to terminals included in the network.

  According to the present invention, a group call is realized by a press talk control server that controls a group call in a first network that realizes a group call by a press talk using a specific communication method, and a press talk other than the specific communication method. And a line control device for controlling the group call in the second network, wherein the press talk control server and the line control device are connected to each other, and the press talk control server is a protocol in the first network. A communication server is used to communicate with the line control device using a protocol in the second network, and a proxy server that performs protocol conversion associated with communication between the press talk control server and the line control device is provided. Between the line controller and the proxy server Sending / receiving group call control data to control group calls between a terminal included in the first network and a terminal included in the second network, and a terminal included in the first network during the group call When a transmission right acquisition request is received from the line connection device, the line connection device is requested to acquire the transmission right through the proxy server, and the transmission right is acquired from the line connection device through the proxy server in the second network. If there is a request to acquire the transmission right from the line connection device via the proxy server, the transmission right is given to the terminal included in the first network. Since the group call system is controlled so as not to be assigned, the proxy server can be used without adding a special function to the existing line control device of the second network. First of different communication schemes by intervention, performs exchange of control data between the second network can be realized group call, there is an effect that it is possible to improve convenience.

[Summary of Invention]
Embodiments of the present invention will be described with reference to the drawings.
A group call system according to an embodiment of the present invention includes a press talk control server that controls group calls in a network using PoC (hereinafter referred to as “A network”), and a network that does not use PoC (hereinafter referred to as “B”). Network ”, for example, an LCU (Line Control Unit) that controls group calls in a self-supporting wireless system, and the like. An LCU proxy server is provided between the A network and the B network, and the LCU proxy server is connected to the LCU. Communicates with the B network protocol, converts the protocol between the A network and the B network, communicates with the press talk control server using the A network protocol, and the press talk control server As with the control, a session with the LCU proxy server is performed to control the transmission right in the group call, and the group call between the A network and the B network is executed. It is intended to and is able to significantly improve the convenience.

[System Overview of Embodiment: FIG. 1]
FIG. 1 is a schematic explanatory diagram of a group call system (present system) according to an embodiment of the present invention.
As shown in FIG. 1, this system connects an A network that makes a group call using PoC, a B network that makes a group call using a communication method other than PoC, and an A network and a B network. And an LCU proxy server 4. The A network assumes a next-generation wireless communication system, and the B network assumes a conventional private wireless system. Then, similarly to the case where the terminals of the A network and the B network perform group calls in the respective networks, the group calls can be performed across the differences in the communication methods. Here, the communication system of the B network will be described as ISDN.
Further, the network A of this system corresponds to the first network in the claims, and the network B corresponds to the second network in the claims.

  The A network includes a press talk control server 1, a BS (Base Station), and a PNC (Private Network Client) 3, and the B network includes an LCU (Line Control Unit). 5, BS 6, and PNC 7.

The press talk control server 1 controls the group call in the A network and controls the group call including the B network via the LCU proxy server 4 as a feature of this system.
The LCU 5 controls the group call of the B network as in the past, and in this system, the group call by the press talk with the A network is realized without adding a special function to the LCU 5. . The LCU 5 corresponds to a “line control device” in the claims.

  The LCU proxy server 4 is a characteristic part of the present system, and has a function of mediating between the A network and the B network by performing protocol conversion of control data exchanged between the press talk control server 1 and the LCU 5. Yes. The LCU proxy server 4 corresponds to a “proxy server” in the claims.

Although not shown, the press talk control server 1, the LCU proxy server 4 and the LCU 5 are configured by a computer. As main constituent means, a control unit including a CPU, a storage unit including a hard disk, and a work of the control unit are provided. A main memory functioning as a memory and an interface unit for exchanging data are provided.
And the function by each processing means in the press talk control server 1, the LCU proxy server 4, and the LCU 5 when the control unit expands and starts the program stored in the memory in the main memory and performs processing according to the program. Is realized.

The PNC 3 of the A network is a press talk terminal (wireless portable terminal) or a telephone terminal. In the case of a wired telephone, it is connected to an ANCF (to be described later) without going through a BS.
The PNC 7 is a wireless mobile terminal of the B network.
BSs 2 and 6 are base stations of the mobile communication system in the respective networks.

The network A's press talk control server 1 and the press talk control server 1 and the LCU proxy server 4 are connected by an IP line, and the BS 2 and the press talk control server 1 are connected by an IP line or an ISDN line. Has been. In the IP line, a session is managed by the TBCP / RTCP protocol.
The B network LCU proxy server 4 and the LCU 5 and the LCU 5 and the BS 6 are connected by ISDN lines. Further, PNC 3 and BS 2 and PNC 7 and BS 6 are connected by wireless communication.

[Processing means of press talk control server 1]
The press talk control server 1 includes an access network control function (ANCF), a private network proxy (PNP), a press-talk server participating function (PTPF), and a press-talk server control function (PTCF) as processing means.

Here, each processing means provided in the press talk control server 1 will be described.
The ANCF controls establishment or release of the access link between the PNC 3 and the PNP in response to a request from the BS 2 or a request from the PNP. If a conventional BS2 is connected, it is controlled by the ISDN protocol.

The PNP converts the transmission right control signal from the ISDN message to TBCP / RTCP or vice versa. Also, media flow control (bandwidth allocation, filtering, QoS marking) is performed.
Note that ANCF and PNP are realized by a gateway, and PNP is a proxy module created in correspondence with a location-registered PNC.

The PTPF stores setting information for each PNC, and performs connection control of the press talk communication based on the setting information (the incoming call priority, whether the response mode is automatic or manual).
The PTCF controls group calls by press talk, and performs group member calling, transmission right management, and PT (Press Talk) voice packet duplication and transfer. In particular, in this system, control data is exchanged with the LCU 5 via the LCU proxy server 4 to realize a group call including the B network of the conventional communication method.

[Processing means of LCU proxy server 4]
The LCU proxy server 4 includes PTPF (LCU) and LCUproxy as processing means.
The PTPF (LCU) communicates with the PTCF of the press talk control server 1 of the A network via the IP line, and performs the same session as the PTPF in the A network to the PTCF to perform a session necessary for the group call. .

  The LCU proxy is connected to the LCU 5 of the B network, communicates with the LCU 5 using the protocol of the B network in the same manner as the BS 6 and the wired telephone of the B network, and distributes the signaling and data (VoIP, PT) received from the LCU 5 Do. At the same time, the LCU proxy performs mutual conversion between the network A protocol (TBCP / RTCP) and the network B protocol (ISDN) for the control signal associated with the group call.

  The group call in the B network is controlled by the LCU 5 as in the conventional case. By providing the LCU proxy server 4, a group call using PoC can be realized between the A network and the B network without modifying the LCU 5 and the BS 6 of the B network.

[Group call overview]
Before describing group call control in this system, an outline of group call will be described.
In this system, the identification number and group number of a member who makes a group call are registered in advance in the network A's press talk control server 1 (the PTCF) and the network B's LCU 5 in advance. As a feature of the system, group call members can include PNCs in different networks.

  For example, in the case of a group composed of members of the A network and the B network, the press talk control server 1 of the A network corresponds to the group number (group number a) managed by the A network and the B of the A network. The group number (group number b) managed by the network is stored, and in the LCU 5 of the B network, the members of the B network and the A network correspond to the group number (group number b) managed by the B network. The group number (group number a) managed by is stored.

  Then, for example, when a group call request including the group number a is transmitted from a member of the network A, the press talk control server 1 calls the member of the network A stored corresponding to the group number a as well as the LCU. A group call request is transmitted to the LCU 5 via the proxy server 4 with the group number b. The LCU 5 calls the member stored corresponding to the group number b.

Then, the press talk control server 1 and the LCU 5 set the responding members to the same group call, the base station (BS) assigns a radio channel to each member, and the group call is started. . During a call, the press talk control server 1 associates group calls between the A network and the B network, and the LCU proxy server 4 performs protocol conversion to mediate communication between the press talk control server 1 and the LCU 5. Thus, when viewed from the A network, a group call with the B network can be realized using PoC, and when viewed from the B network, a group call with the A network is realized using conventional ISDN.
The transmission right control during a call performed by the press talk control server 1 is a feature of this system, and will be described in detail later.

[Example of functional configuration during group call: Fig. 2]
Next, a functional configuration example of the present system during a group call will be described with reference to FIG. FIG. 2 is a schematic explanatory diagram illustrating a functional configuration example of the system.
As shown in FIG. 2, in network A, three base stations BS1, BS2, and BS3 are connected to the press talk control server 1, and two terminals, PNC (A) and PNC (D), are connected to BS1. The location is registered, the location of PNC (B) is registered in BS2, and the location of PNC (C) is registered in BS3. PNC (A) to PNC (D) are members of the group call.

In the press talk control server 1, proxy modules corresponding to each PNC are created, and PNP (A) and PTPF (A) are created for PNC (A) and connected to BS1 by ANCF. .
The PTCF performs a session with the PTPF (A) to PTPF (D) to control the group call in the A network. Similarly, the PTCF communicates with the PTPF (LCU) of the LCU proxy server 4 to perform the A network. And control the group call between the B network and the B network.

  A TCF (Transcoding Function) of the press talk control server 1 performs a voice codec conversion process, and duplicates voice data corresponding to the codec used in each of the A network and the B network. The duplicated audio data is distributed to the members of the group call by PTCF.

The LCU proxy server 4 that connects the A network and the B network is the same as that shown in FIG. 1, and includes a PTPF (LCU) and an LCU proxy that performs protocol conversion.
The B network is composed of an LCU 5 and a PNC 7. In the example of FIG. 2, the PNC 7 of the B network is a wired telephone and is connected to the LCU 5 without going through the BS. A BS connected to the LCU 5 may be provided as shown in FIG.

[Transmission right control sequence]
Next, a procedure when a group call is started in the system shown in FIG. 2 and a member acquires a transmission right will be described.
[Acquisition of transmission right from network A to network B (when successful): FIG. 3, FIG. 4, FIG. 5]
First, an example in which a transmission right is requested from the A network to the B network and acquisition is successful will be described with reference to FIGS. 3 to 5 are schematic explanatory diagrams showing a sequence of acquiring a transmission right from the A network to the B network (when succeeding), and FIGS. 3, 4, and 5 are connected in time series. .

  As shown in FIG. 3, when the PNC (A) of the network A detects that the transmission button is pressed (101) in the state where transmission is possible, the ANCF + PNP of the press talk control server 1 through the corresponding base station BS1. A “transmission right confirmation” is transmitted to (A) (102). The transmission right confirmation may not include the transmission source terminal information, and in this case, only the information that it is a transmission right confirmation request from BS1 is transmitted.

  The ANCF + PNP (A) that has received the transmission right confirmation request selects a representative member for the source BS (103). Here, the PNP of the PNC (A) that is called as a member of the corresponding group call and registered in the BS 1 (ie, PNP (A)) is selected as a representative.

  The ANCF + PNP (A) transmits “Talk Burst Request” to the PTPF (A) (104), and the PTPF (A) transmits “Talk Burst Request” to the PTCF (105).

The PTCF that manages the transmission right in the A network confirms that no transmission right has been acquired in the A network (106), and notifies the members of the A network of the transmission right display (110). .
At the same time, the PTCF transmits “Talk Burst Request” to the PTPF (LCU) of the LCU proxy server 4 in order to confirm the transmission right to the B network (107).

  Then, the PTPF (LCU) transmits “Talk Burst Request” to the LCU proxy (108), and the LCU proxy converts the control data into the protocol of the B network and transmits “transmission right confirmation” to the LCU 5 (109). .

On the other hand, the PTCF of the A network notifies the other members of the transmission right display while the B network is confirming the transmission right.
First, the PTCF transmits “Talk Burst Taken” to the PTPF (B) (111), and the PTPF (B) transmits “Talk Burst Taken” to the ANCF + PNP (B) (112).

  The ANCF + PNP (B) specifies the BS of the member B (PNC (B)) (113), confirms that the BS is different from the BS of the member A (114), and further displays a transmission right indication to the BS. It is confirmed that it has not been performed yet (115), and a transmission right display indicating that member A is requesting transmission right is notified to BS2 + PNC (B) (116).

  In addition, the PTCF transmits “Talk Burst Taken” to the PTPF (D) (117), and the PTPF (D) transmits “Talk Burst Taken” to the ANCF + PNP (D) (118).

  When ANCF + PNP (D) identifies the BS of member D (PNC (D) (119) and confirms that it is the same BS1 as the BS of member A (120), the transmission right indication to the BS is displayed as member A In this case, the display of the transmission right is not notified (121).

Next, description will be made with reference to FIG.
As shown in FIG. 4, for example, when the PNC (C) of the A network detects that the transmission button is pressed (122), the base station BS3 sends “Transmission right” to the ANCF + PNP (C) of the press talk control server 1. “Confirm” is transmitted (123). ANCF + PNP (C) selects a representative PNP for the source BS. Here, the PNP of PNC (C) is selected as a representative (124).

  Then, the ANCF + PNP (C) transmits “Talk Burst Request” to the PTPF (C) (125), and the PTPF (C) transmits “Talk Burst Request” to the PTCF (126).

When receiving the “Talk Burst Request”, the PTCF confirms that the member A is requesting the transmission right (127), and transmits the “Talk Burst Deny” rejecting the transmission right to the PTPF (C) (128). .
The PTPF (C) transmits “Talk Burst Deny” to the ANCF + PNP (C) (129), and the ANCF + PNP (C) specifies the BS of the member C (130) and is a BS different from the member A (131). When it is confirmed that the transmission right display to the BS is not performed (132), the transmission indicating that member A is requesting transmission right and the request from member C is not accepted is sent to BS3 + PNC (C). The right display is notified (133).

  On the other hand, independently of the processing in the network A, the LCU of the network B receives the transmission right confirmation from the LCU proxy (processing 109 in FIG. 3), and no member of the group call in the B network has the transmission right. It confirms that it has not been acquired (140), and notifies the transmission right display to the members in the B network (141).

Furthermore, it demonstrates using FIG.
Then, the LCU of the B network transmits “transmission right acceptance” to the LCU proxy (142), the LCU proxy converts it to the protocol of the A network, and transmits “Talk Burst Granted” to the PTPF (LCU) (143). ), The PTPF (LCU) transmits “Talk Burst Granted” to the PTCF of the A network (144).

  PTCF sends “Talk Burst Granted” to PTPF (A) (145), PTPF (A) sends “Talk Burst Granted” to ANCF + PNP (A) (146), and ANCF + PNP (A) is a member. A's BS is identified (147), and "transmission right acceptance" is transmitted to BS1 + PNC (A) (148). Thereby, the transmission right is obtained for the PNC (A). Here, a transmission right indication indicating that the member A has obtained the transmission right is transmitted to the PNC (D).

  When a voice packet is transmitted from the PNC (A) that has obtained the transmission right to the PTCF via BS1, ANCF + PNP (A), and PTPF (A) (149 to 151), the PTCF sends voice data to the TCF. The codec conversion instruction is output (152), and the audio data corresponding to the codec used is duplicated and transmitted to the group members (153).

  The PTCF sends a voice packet to the LCU proxy via the PTPF (LCU) (154, 155), the LCU proxy converts it into voice data and sends it to the LCU (156). Distribute voice data to group members.

In the A network, the PTCF transmits a voice packet to the ANCF + PNP (B) via the PTPF (B) for the member B (160, 161), and the ANCF + PNP (B) specifies the BS of the member B (162). When it is confirmed that the voice packet transfer to the BS has not been performed yet (163), the voice packet is transmitted to BS2 + PNC (B) (164).
Similarly, the PTCF transmits voice packets to members C (165 to 169) and member D (170 to 174).
In this manner, a sequence is performed when acquisition of transmission rights from the A network to the B network is successful.

[Acquisition of transmission right from network A to network B (in case of failure): FIGS. 6 and 7]
Next, an example in which a transmission right is requested from the A network to the B network and acquisition fails will be described with reference to FIGS. FIGS. 6 and 7 are schematic explanatory diagrams showing a sequence of acquiring a transmission right from the A network to the B network (in the case of failure), and FIGS. 6 and 7 are connected in time series. In order to simplify the explanation, it is assumed here that the members of the A network are only PNC (A) and PNC (B).

As shown in FIG. 6, processes 201 to 216 in this sequence are the same as the processes 101 to 116 shown in FIG. 3, and therefore, detailed description is omitted here, and only the outline is described.
In a state where transmission is possible, PNC (A) detects that the transmission button is pressed (201), and “Talk Burst Request” is transmitted to PTCF via BS1, ANCF + PNP (A), ANCF + PNP (A), and PTPF (A). (203-205).

The PTCF confirms that no transmission right has been acquired in the A network (206), and notifies the transmission right display to members of the A network (210).
At the same time, the PTCF transmits “Talk Burst Request” to the PTPF (LCU) of the LCU proxy server 4 in order to confirm the transmission right to the B network (207).

  The PTPF (LCU) transmits “Talk Burst Request” to the LCU proxy (208), and the LCU proxy converts the control data to the protocol of the B network and transmits “transmission right confirmation” to the LCU 5 (209).

As shown in FIG. 3, the PTCF notifies the members in the network A of the transmission right indication (210 to 216).
On the other hand, the LCU of the B network confirms the transmission right of the group member and confirms that the transmission right is assigned to any member in the B network (220), and displays “transmission right display” on the LCU proxy. Transmit (221).

  When the LCU proxy receives the “transmission right indication” from the LCU, the LCU proxy converts it to the protocol of the network A, transmits “Talk Burst Deny” to the PTPF (LCU) (222), and the PTPF (LCU) “Talk Burst Deny”. Is transmitted to the PTCF of the A network (223).

  When PTCF sends “Talk Burst Deny” to member A, ANCF + PNP (A) is received via PTPF (A) (224, 225), and ANCF + PNP (A) identifies the BS of PNC (A). (226), and a “transmission right indication” is transmitted to the BS 1 (227). Thereby, PNC (A) displays that the transmission right was not acquired.

Next, description will be made with reference to FIG.
Then, when a terminal having a transmission right in the B network performs transmission, voice data is input to the LCU proxy via the LCU (230), and the LCU proxy converts the voice data into a voice packet and converts it into a PTPF ( LCU) (231). The PTPF (LCU) transmits a voice packet to the PTCF (232).

When the PTCF receives the voice packet, it performs codec conversion (233), duplicates and transmits voice data corresponding to the codec used to the group member (234), and member A (235-239) in the A network. The voice packet is transmitted to member B (240 to 244).
In this way, a sequence is performed when acquisition of the transmission right from the A network to the B network fails.

[Acquisition of transmission right from network B to network A (when successful): FIG. 8]
Next, an example in which a transmission right is requested from the B network to the A network and acquisition is successful will be described with reference to FIG. FIG. 8 is a schematic explanatory diagram illustrating a sequence for acquiring a transmission right from the B network to the A network (when successful). Here, in order to simplify the explanation, the member in the A network is only PNC (A).

  As shown in FIG. 8, when the LCU detects that a member in the network B has pressed the transmission button in the state where transmission is possible (301), the LCU transmits “transmission right display” to the LCU proxy ( 302), the LCU proxy converts to the protocol of the A network and transmits “Talk Burst Taken” to the PTPF (LCU) (303). Then, the PTPF (LCU) transmits “Talk Burst Taken” to the PTCF of the A network (304).

When the PTCF receives “Talk Burst Taken” from the PTPF (LCU), the PTCF notifies the members in the A network of the transmission right indication (305).
That is, the PTCF transmits “Talk Burst Taken” to the PTPF (A) (306), and the PTPF (A) transmits “Talk Burst Taken” to the ANCF + PNP (A) (307).

  The ANCF + PNP (A) specifies the BS of the member A (308), and when the transmission right display to the BS is not yet performed (309), transmits “transmission right display” to BS1 + PNC (A). (310).

  Then, when voice data is transmitted from the member in the B network that has acquired the transmission right, the LCU receives this and outputs it to the LCU proxy (311), and the LCU proxy converts it into a voice packet and PTPF (LCU) (312), and the PTPF (LCU) transmits a voice packet to the PTCF of the A network (313).

The PTCF receives the voice packet, outputs an instruction for codec conversion of the voice data to the TCF, performs codec conversion (314), and duplicates and transmits the voice data corresponding to the codec used to the group member (315).
Then, the PTCF transmits the voice packet to PNC (A) via PTPF (A), ANCF + PNP (A), and BS1 (316 to 320).
In this way, the sequence in the case where the transmission right from the B network to the A network is successfully acquired is performed.

[Group call transmission right release from network A: Fig. 9]
Next, a sequence for releasing the transmission right from the network A will be described with reference to FIG. FIG. 9 is a schematic explanatory diagram showing a sequence for releasing the group call transmission right from the network A.
As shown in FIG. 9, when the release of the transmission button is detected by the PNC (A) of the network A (401), “transmission right release” is transmitted to the ANCF + PNP (A) via the BS (402). The ANCF + PNP (A) selects a representative member at the stage of acquiring the transmission right for the transmission source BS (403). Here, it is assumed that the PNP of PNC (A) is selected as a representative.

  Then, the ANCF + PNP (A) transmits “Talk Burst Release” to the PTPF (A) (404), and the PTPF (A) transmits “Talk Burst Release” to the PTCF (405).

  The PTCF notifies the members in the network A of the release of the transmission right (407) and also transmits a “Talk Burst Release” to the PTPF (LCU) (406) to notify the members of the network B, and the PTPF (LCU) transmits the LCU. “Talk Burst Release” is transmitted to the proxy (408). The LCU proxy converts to the protocol of the B network and transmits “transmission right release” to the LCU (409).

The PTPF transmits “Talk Burst Idle” to the member B other than the sender (member A), and the “Talk Burst Idle” is received by the ANCF + PNP (B) via the PTPF (B) (411, 412). ).
When ANCF + PNP (B) receives “Talk Burst Idle”, it identifies the BS of member B (413). If the transmission right to the BS has not been released yet (414), PNC ( “Transmission right release” is transmitted to B) (415).

  Then, the PTCF transmits “Talk Burst Idle” to the member A who is the speaker via PTPF (A) (416), and ANCF + PNP (A) receives “Talk Burst Idle” (417). Then, the ANCF + PNP (A) transmits “transmission right release” to the PNC (A) via the BS (418 to 420).

On the other hand, when receiving the “transmission right release” (409), the LCU of the network B releases the transmission right (410) and transmits “transmission right release” to the LCU proxy (421).
The LCU proxy performs protocol conversion and transmits “Talk Burst Idle” to the PTPF (LCU) (422), and the PTPF (LCU) transmits “Talk Burst Idle” to the PTCF of the A network (423).
Then, the state shifts to a state where transmission is possible.
In this way, the transmission right release sequence from the network A is performed.

[Group call transmission right release from network B: FIG. 10]
Next, a sequence for releasing the transmission right from the B network will be described with reference to FIG. FIG. 10 is a schematic explanatory diagram showing a sequence for releasing a group call transmission right from the B network.
As shown in FIG. 10, when the LCU of the network B detects the release of the transmission button from any member in the network B (501), the LCU transmits “transmission right release” to the LCU proxy (502). ), The LCU proxy converts to the protocol of the A network and transmits “Talk Burst Idle” to the PTPF (LCU) (503). The PTPF (LCU) transmits “Talk Burst Idle” to the PTCF of the A network (504).

  The PTCF transmits “Talk Burst Idle” to the PTPF (A) (506), and the PTPF (A) transmits “Talk Burst Idle” to the ANCF + PNP (A) (507).

The ANCF + PNP (A) transmits “transmission right release” to the PNC (A) via the BS (508 to 510).
Then, the state shifts to a state where transmission is possible.
In this way, the transmission right release sequence from the network B is performed.

[Effect of the embodiment]
According to the group call system according to the embodiment of the present invention, between the A network that performs group call by press talk using PoC and the B network that performs group call by, for example, ISDN communication without using PoC, An LCU proxy server 4 for connecting the A network and the B network is provided, and the LCU proxy server 4 is connected to the press talk control server 1 for controlling the group call of the A network via an IP line and behaves like a BS of the A network. It is connected to the PTPF (LCU) and the LCU that controls the group call of the B network through an ISDN line and behaves like the BS of the B network. LCU proxy that performs mutual conversion of the B network, without adding a special function to the L network 5 of the conventional network B It is possible to realize a group call between the network A and network B, there is an effect that it is possible to improve convenience.

  Further, according to the present system, the press talk control server 1 requests the LCU 5 to acquire the transmission right via the LCU proxy server 4 when a request for acquisition of the transmission right is received from a member of the network A during the group call. When the member in the network B receives from the LCU 5 via the LCU proxy server 4 that the transmission right has not been acquired, the transmission right is given to the member in the network A that is the requester of the transmission right. Since the group call system notifies the other member of the transmission right indication indicating that another member has acquired the transmission right, when the transmission right is requested by a member of the A network, transmission of the B network The transmission right can be given to the requester of the A network after confirming the right, and other members can transmit the transmission right to members other than the requester of the A network by effectively using the time inquired to the B network. With a notification that , Between networks of different communication systems, the effect of the transmission right control of the group call can be performed smoothly.

  Further, according to the present system, when the press talk control server 1 makes a transmission right acquisition request from the LCU 5 via the LCU proxy server 4 during the group call, the B network transmits to the members in the A network. Since the group call system notifies the transmission right display indicating that the right has been acquired, when there is a transmission right acquisition request from the B network, the transmission right is not given to the members of the A network, and the smooth group There is an effect that a call can be realized.

  Further, according to the present system, when the press talk control server 1 receives a transmission right acquisition request from a member of the A network and inquires the LCU for the transmission right of the B network via the LCU proxy server 4, When there is a transmission right acquisition request from another member of the network A, the transmission right is not given to another member, so that transmission right control can be performed smoothly.

  The present invention is suitable for a group call system that enables group calls between networks having different communication methods.

It is a schematic explanatory drawing of the group call system (this system) concerning an embodiment of the invention. It is a schematic explanatory view showing a functional configuration example of the system. It is a schematic explanatory drawing which shows the sequence of acquisition (when succeeding) of the transmission right with respect to B network from A network. It is a schematic explanatory drawing which shows the sequence of acquisition (when succeeding) of the transmission right with respect to B network from A network. It is a schematic explanatory drawing which shows the sequence of acquisition (when succeeding) of the transmission right with respect to B network from A network. It is a schematic explanatory drawing which shows the sequence of acquisition of the transmission right from A network to B network (when it fails). It is a schematic explanatory drawing which shows the sequence of acquisition of the transmission right from A network to B network (when it fails). It is a schematic explanatory drawing which shows the sequence of acquisition (when succeeding) of the transmission right with respect to A network from B network. It is a schematic explanatory diagram showing a sequence for releasing the group call transmission right from the A network. It is a schematic explanatory diagram showing a sequence for releasing the group call transmission right from the B network.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Press talk control server, 2 ... BS (base station), 3 ... PNC (terminal), 4 ... LCU proxy server, 5 ... LCU (line control unit), 6 ... BS, 7 ... PNC

Claims (1)

A press talk control server that controls a group call in a first network that realizes a group call by a press talk using a specific communication method, and a second network that realizes a group call by a press talk other than the specific communication method A group call system having a line control device for controlling group calls in
The press talk control server and the line control device are connected, the press talk control server communicates with the protocol in the first network, and the line control device communicates with the protocol in the second network. And a proxy server for performing protocol conversion associated with communication between the press talk control server and the line control device,
The press talk control server transmits / receives group call control data to / from the line control device via the proxy server, and a terminal included in the first network and a terminal included in the second network Control group calls to and from
During a group call, if there is a transmission right acquisition request from a terminal included in the first network, the line connection device is requested to acquire the transmission right via the proxy server, and the line connection device When receiving from the proxy server that the transmission right is not acquired in the second network, the transmission right is granted to the requesting terminal, and the transmission right is transmitted from the line connection device via the proxy server. When a request for acquisition is received, a group call system is controlled so that a transmission right is not granted to a terminal included in the first network.

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