System and method for group session communication

BACKGROUND OF THE INVENTION

00011. Field of the Invention

0002The present invention relates to a Push to talk over Cellular (PoC), and more particularly to a system and method for group session communication that enable to distribute presence information by voice data information.

00032. Description of the Related Art

0004<figref idref="DRAWINGS">FIG. 6</figref> is an example of a sequence chart illustrating how the group members (participants) of a group session communication recognize a newly joining member to this group session and an exited member from this group session during the group session communication using voice group communication in an existing Push to talk over Cellular (PoC) system. The group members are radio communication terminals <b>10</b> through <b>30</b>, and the radio communication terminal <b>10</b> is assumed to have established the group session.

0005In the initial state, the radio communication terminals participating in the group session (group session members) are the radio communication terminal <b>10</b> and radio communication terminal <b>20</b>, and the radio communication terminal <b>10</b>, as a creator of the group sesion, is conducting voice communication with the radio communication terminal <b>20</b>. The radio communication terminal <b>30</b> is receiving an invite signal from the radio communication terminal <b>10</b> via a communication system <b>100</b>. However, the radio communication terminal <b>30</b> is not responding to this invite signal at this time point.

0006The voice signal that is input to the radio communication terminal <b>10</b> is transformed to voice data M<b>200</b> and transmitted to the radio communication terminal <b>20</b> via the communication system <b>100</b>.

0007Then, the radio communication terminal <b>30</b> sends back a join response (S<b>200</b>), responding to the invite request, transmitted from the radio communication terminal <b>10</b>, to join this group session. Based on the join response transmitted from the radio communication terminal <b>30</b>, the communication system <b>100</b> recognizes that the radio communication terminal <b>30</b> is a newly joining member to this group session. The communication system <b>100</b> notifies all the participants (the radio communication terminals <b>10</b> through <b>30</b>) presence information (S<b>210</b>) that indicates “join” status, etc. to the group session of the radio communication terminals <b>10</b> through <b>30</b>. Generally, the participants are required to confirm visually this presence information displayed on own radio communication terminal.

0008After the radio communication terminal <b>30</b> has joined the group session communication, voice data M<b>210</b> generated by transforming the voice signal that is input to the radio communication terminal <b>10</b> are transmitted, via the communication system <b>100</b>, to the radio communication terminal <b>20</b> and the newly joined radio communication terminal <b>30</b>.

0009Next, a case in which the radio communication terminal <b>20</b> exits the group session is explained.

0010When the radio communication terminal <b>20</b> transmits an exit request (S<b>220</b>) from the group session communication, the communication system <b>100</b> receives this exit request and sends back to the radio communication terminal <b>20</b> an exit response (S<b>230</b>) from the group session communication. The communication system <b>100</b> then notifies the radio communication terminal <b>10</b> and the radio communication terminal <b>30</b> with presence information on the radio communication terminals <b>10</b> through <b>30</b> (S<b>240</b>). Upon receiving this notification, the radio communication terminal <b>10</b> and the radio communication terminal <b>30</b> recognize that the radio communication terminal <b>20</b> has exited the group session. The participants are also required to confirm visually this presence information displayed on the terminal.

0011After the radio communication terminal <b>20</b> has exited the group session, voice data M<b>220</b> generated by transforming the voice signal that is input to the radio communication terminal <b>10</b> are transmitted, via the communication system <b>100</b>, only to the radio communication terminal <b>30</b> who is the current participant of the group session.

0012The operations of the communication system as explained above, i.e., the conventional art related to the communication system that notifies other participants with increase and decrease of the number of the group session members is disclosed in Japanese Patent Laid-open No. 1992-290361.

0013In the existing communication system described above, information (terminal numbers, etc.) on the terminals joining the group session or the terminals exiting the group session is displayed on the terminals of all the participants of the group session. In the existing communication system, all the participants are notified with increase and decrease of the number of the group session members.

0014However, during the group session being established, the group session members are required to pay their attentions to visual signals transmitted from the speaker and documents related to the discussion. Consequently, it is possible for the group session members easily to pass over such presence information on the terminals joining the group session or exiting the group session.

0015Further, in a PoC using mobile terminals, during the group session communication, it is difficult for the group session members to watch the terminal display because they hold the mobile terminal at an ear for the communication. Thus, the group session members possibly pass over the displayed presence information.

0016As was described, the existing communication system has such a problem that it is difficult for the group session members to recognize the presence information which indicates increase and decrease of the number of the participants of the group session.

SUMMARY OF THE INVENTION

0017The present invention has invented to solve the above described problem, and aims to provide a communication system which makes it easier for the group session members to recognize the presence information which indicates increase and decrease of the number of the participants of the group session communication.

0018According to the present invention, all participants of the group session communication can recognize the status change of participants by voice data information. The communication system according to the present invention comprises a call control server and a media control server. The call control server accepts a request from each of the group members for joining or exiting the group session communication. A predetermined number of communication terminals are defined as group members who organize a group of the group session communication. When the call control server has accepted the request from one of group members for joining or exiting the group session communication, the call control server transmits information on the group member to the media control server. The media control server extracts media data, from a memory means, corresponding to the information on the group member, and distributes the media data as voice data information to all group members participating in the group session communication.

0019According to the present invention, a communication system which makes it easier for the group members to recognize the presence information indicating increase and decrease of the number of the participants of the group session communication is realized.

BRIEF DESCRIPTION OF THE DRAWINGS

0020The above and further objects, exemplary novel features and advantages of the present invention will be more fully understood from the following detailed description when read together with the accompanying drawings in which:

0021<figref idref="DRAWINGS">FIG. 1</figref> is a diagram showing a communication system that relates to the present invention;

0022<figref idref="DRAWINGS">FIG. 2</figref> is a diagram showing an example of the structure of the group attributes data;

0023<figref idref="DRAWINGS">FIG. 3</figref> is a sequence chart showing an example of the operation of the communication system;

0024<figref idref="DRAWINGS">FIG. 4</figref> is a sequence chart showing an example of the operation for a radio communication terminal newly joining the group session;

0025<figref idref="DRAWINGS">FIG. 5</figref> is a sequence chart showing an example of the operation for a radio communication terminal exiting the group session; and

0026<figref idref="DRAWINGS">FIG. 6</figref> is a sequence chart showing the operation of an existing communication system.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

0027A preferred embodiment of the present invention is described below. <figref idref="DRAWINGS">FIG. 1</figref> shows the structure of a communication system including a group voice communication system <b>100</b> of the present embodiment.

0028The group voice communication system <b>100</b> is connected to radio communication terminals <b>10</b>, <b>20</b> and <b>30</b> through a network <b>200</b> and base stations <b>310</b> and <b>320</b>. The group voice communication system <b>100</b> is a system that realizes group session communication represented by a PoC, and mainly performs call control, media control, group list management and presence information management related to group session communication.

0029Within the group voice communication system <b>100</b>, a call control server <b>110</b> mainly performs call control for group session communication using voice group communication. The call control server <b>110</b> also performs routing among the radio communication terminals <b>10</b>, <b>20</b> and <b>30</b>, a media control server <b>120</b>, a presence information management server <b>140</b>, etc.

0030The media control server <b>120</b> mainly performs management and control for group session using voice group communication, distribution of voice media (which are media data distributed to the radio communication terminals currently participating the session to notify “join to the session” and “exit from the session”), or session member information.

0031The group list management server <b>130</b> mainly manages information related to the group and the members.

0032The presence information management server <b>140</b> mainly performs management and distribution of the presence information on the members. For example, the presence information server <b>140</b> performs unified management of member status such as “join to the session” or “exit from the session,” or “conference in progress” and “out for lunch.”

0033<figref idref="DRAWINGS">FIG. 2</figref> shows an example of the data structure of the information on the group and the members that are managed by the group list management server <b>130</b>.

0034The group member list information shown in <figref idref="DRAWINGS">FIG. 2</figref> is defined by the manager of the group for each member. In the field of media data, a media type (“voice” in the present embodiment) which the media control server <b>120</b> can deal with, is stored.

0035The media data themselves. (voice data) are pre-stored (memorized) in the media control server <b>120</b> by the manager of the group, and distributed to the group session members by the media control server <b>120</b>.

0036Since the radio communication terminals <b>10</b> through <b>30</b>, the network <b>200</b>, base stations <b>310</b> and <b>320</b> according to the conventional art can be applied to the present embodiment, detailed explanation of the structure of these constituents is omitted.

0037In the following, operation for recognizing “join to” and “exit from” the session is explained which occur during the group session communication in the group voice communication system related to the present invention.

0038<figref idref="DRAWINGS">FIG. 3</figref> is an example of the operation sequence.

0039In this example, the group session members are radio communication terminals <b>10</b> through <b>30</b>. And the radio communication terminal <b>10</b> establishes the session. In the initial state, the radio communication terminal <b>10</b> and the radio communication terminal <b>20</b> are participants of the session. The radio communication terminal <b>10</b> is the speaker and is communicating with the radio communication terminal <b>20</b>. Only the radio communication terminals <b>20</b> and <b>30</b> who are invited by the radio communication terminal <b>10</b> can join this session. Other radio communication terminals cannot join the session.

0040The voice signal that is input to the radio communication terminal <b>10</b> is transformed to voice data M<b>100</b> and transmitted to the radio communication terminal <b>20</b> via the communication system <b>100</b>.

0041The radio communication terminal <b>30</b> sends back a join response (S<b>100</b>), responding to the invite request to join this group session transmitted from the radio communication terminal <b>10</b>. Then, based on the join response transmitted from the radio communication terminal <b>30</b>, the communication system <b>100</b> recognizes that the radio communication terminal <b>30</b> is a newly joining member to this group session.

0042The presence information management server <b>140</b> of the communication system <b>100</b> notifies all the participants with presence information, in a visually recognizable form, that the radio communication terminal <b>30</b> has newly joined the session (S<b>110</b>).

0043<figref idref="DRAWINGS">FIG. 4</figref> shows the detailed operation within the group voice communication system <b>100</b> from the time when the radio communication terminal <b>30</b> transmits a session join response until the time when the media control server <b>120</b> outputs a session join notification as media data (voice data). In <figref idref="DRAWINGS">FIG. 4</figref>, “server” is denoted with abbreviation “SV.”

0044The call control server <b>110</b> receives a session join response from the radio communication terminal <b>30</b> (S<b>100</b>). The call control server <b>110</b> acquires information on the newly joining member to the group session from the message presenting the session join response, and notifies the media control server <b>120</b> (S<b>111</b>).

0045The media control server <b>120</b> receives from the call control server <b>110</b> the information on the newly joining member to the session. Then, the media control server <b>120</b> transmits to the group list management server <b>130</b> an acquire request for information on the newly joining member as a group member (S<b>112</b>).

0046The group list management server <b>130</b>, upon receiving the acquire request for information on the group member, finds information on the group member newly joining the session from within the group attributes data and responds to the media control server <b>120</b> (S<b>113</b>).

0047The media control server <b>120</b> receives the information on the group member responded from the group list management server <b>130</b>. The media control server <b>120</b> confirms whether media data corresponding to the acquired information on the group member are stored or not, and responds to the call control server <b>110</b> with the information on the newly joining member to the group session (S<b>114</b>).

0048The media control server <b>120</b> also reads out the media data corresponding to the acquired information on the group member from a built-in memory or an externally attached memory device, and distributes this media data M<b>110</b> (voice data) as a session join notification to the radio communication terminals <b>10</b> and <b>20</b> who are the current participants of the group session. For example, the media control server <b>120</b> distributes to the radio communication terminals <b>10</b> and <b>20</b>, the current participants of the group session, such voice data as “The user Mr. A of the radio communication terminal <b>30</b> has joined the session” as a session join notification (M<b>110</b>).

0049While the radio communication terminal <b>10</b> and the radio communication terminal <b>20</b> are continuing group session communication, the users of both radio communication terminals recognize, by receiving the media data M<b>110</b> from the group voice communication system <b>100</b>, that the radio communication terminal <b>30</b> has joined the session.

0050Now, the explanation continues with <figref idref="DRAWINGS">FIG. 3</figref> again.

0051As the radio communication terminal <b>30</b> has joined the session, the voice signal that is input to the radio communication terminal <b>10</b> is transformed to voice data M<b>120</b> and transmitted not only to the radio communication terminal <b>20</b> but also to the radio communication terminal <b>30</b>.

0052<figref idref="DRAWINGS">FIG. 5</figref> shows the detailed operation within the group voice communication system <b>100</b> from the time when the radio communication terminal <b>20</b> transmits a session exit request until the time when the media control server <b>120</b> outputs a session exit notification as media data (voice data). In <figref idref="DRAWINGS">FIG. 5</figref>, “server” is denoted with abbreviation “SV.”

0053The call control server <b>110</b> receives a session exit request from the radio communication terminal <b>20</b> (S<b>120</b>). While the call control server <b>110</b> responds to the radio communication server <b>20</b> with a session exit response (S<b>130</b>), it also acquires information on the exiting member from the group session from the message presenting the session exit request, and notifies the media control server <b>120</b> (S<b>141</b>).

0054The media control server <b>120</b> receives from the call control server <b>110</b> the information on the exiting member from the session. Then, the media control server <b>120</b> transmits to the group list management server <b>130</b> an acquire request for information on the exiting member as a group member (S<b>142</b>).

0055The group list management server <b>130</b>, upon receiving the acquire request for information on the group member, finds information on the group member exiting the session from within the group attributes data and responds to the media control server <b>120</b> (S<b>143</b>).

0056The media control server <b>120</b> receives the information on the group member responded from the group list management server <b>130</b>. The media control server <b>120</b> confirms whether media data corresponding to the acquired information on the group member are stored or not, and responds to the call control server <b>110</b> with the information on the exiting member from the group session (S<b>144</b>).

0057The media control server <b>120</b> also reads out the media data corresponding to the acquired information on the group member from a built-in memory or an externally attached memory device, and distributes this media data M<b>130</b> (voice data) as a session exit notification to the radio communication terminals <b>10</b> and <b>30</b> who are the current participants of the group session. For example, the media control server <b>120</b> distributes to the radio communication terminals <b>10</b> and <b>30</b>, the current participants of the group session, such voice data as “The user Mr. B of the radio communication terminal <b>20</b> has exited the session” as a session exit notification (M<b>130</b>).

0058Now, the explanation continues with <figref idref="DRAWINGS">FIG. 3</figref> again.

0059As the radio communication terminal <b>20</b> has exited the session, the voice signal that is input to the radio communication terminal <b>10</b> is transformed to voice data M<b>140</b> and transmitted only to the radio communication terminal <b>30</b>.

0060As is explained above, since the group voice communication system according to the present embodiment uses voice data as the media data for notifying other participants with presence information indicating increase and decrease of the number of the participants of the session, the participants are able to recognize “join” and “exit” of other members without a visual means. Therefore, since the communication system uses voice data as the media data, the participants are able to recognize “join” and “exit” of other participants without passing over such information.

0061And, since a server within the group voice communication system <b>100</b> manages media data, information management at the radio communication terminals can be simplified.

0062And, since a server within the group voice communication system <b>100</b> manages media data, media data for the radio communication terminals joining the group session can be distributed simultaneously.

0063Furthermore, as is described above, since the manager of the group stores the media data themselves (voice data) in the media control server <b>120</b>, i.e., the manager of the group manages the content of the media data, it is possible to prevent any false content from being registered as media data. In other words, if the user of each radio communication terminal individually registers media data, then registration under a false name is possible, and there may be a danger that newly joining members to the group session or exiting members from the group session can not be identified. However, in the group voice communication system according to the present embodiment, there exists no such danger.

0064And, since a radio communication terminal can join the group session by responding to the call from the inviting member, uninvited ones never join the group session.

0065Further, the above embodiment is a preferred example of the present invention, and the present invention is not limited to this embodiment.

0066In the above embodiment, a case is explained where the media control server <b>120</b> distributes media data in the group attributes data without any modification. However, the media control server <b>120</b> can modify and distribute the media data in the group attributes data (e.g., unify the form of expression or adjust the replay time).

0067And, in the above embodiment, a case is described as an example where the radio communication terminals perform voice group session each other, but the present invention can be applied as far as the group session is run including at least voice communication. In this case, the media data should include at least voice, and in addition to voice the media data may include moving pictures, still pictures, texts, etc.

0068And, when the present invention is applied to a case where only the manager of the group is able to recognize the participants of the group session, the participants are unable to identify newly joining members or exiting members, and media data (e.g., melody, etc.) only identifiable by the manager of the group may be used.

0069And a communication terminal for group session communication is not necessarily a radio communication terminal, but may be a communication terminal connected to the network with wire.

0070And, in the above embodiment, a case is explained where the group voice communication system is implemented with hardware such as servers, etc. However, the present invention is realizable using programs which can implement the functions of these servers <b>110</b> through <b>140</b>.

0071In this way, the present invention allows various modifications.

0072The previous description of embodiment is provided to enable a person skilled in the art to make and use the present invention. Moreover, various modifications to this embodiment will be readily apparent to those skilled in the art, and the generic principles and specific examples defined herein may be applied to other embodiments without the use of inventive faculty. Therefore, the present invention is not intended to be limited to the embodiment described herein but is to be accorded with the widest scope as defined by the limitations of the claims and equivalents.

0073Further, it is noted that the inventor's intent is to refrain all equivalents of the claimed invention even if the claims are amended during prosecution.