Method for managing location information, related relay device and location information management device

• US 7,058,410 B2
• Filed: 10/21/2002
• Issued: 06/06/2006
• Est. Priority Date: 10/23/2001
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Hiyama, Satoshi, Sasada, Koji
• Primary Examiner(s): Vuong, Quochien B.
• Application Number:
  US10/274,843
• Publication Number:
  US 20030092443A1
• Time in Patent Office: 1,324 Days
• Field of Search: 455/422.1, 455/433, 455/435.1, 455/456.1, 342/357.01, 342/45, 340/988, 340/989
• US Class Current: 455/456.1
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A location register 13 stores as location information of a relay device 21 to area identification information of a location registration area where relay device 21 is currently located and stores as location information of one or a plurality of mobile communication terminals 7 transported in a moving object 2, relay device identification information of relay device 21 to thereby subordinate one or more of a plurality of mobile communication terminals 7 to relay device 21. In the case that a master/slave relationship should be discontinued with some of a plurality of mobile communication terminals 7, relay device 21 transmits, to location register 13, a dependency registration removal request specifying the part of a plurality of mobile communication terminals 7. Location register 13 updates location information of the mobile communication terminals 7 specified in the dependency registration removal request to area identification information of a location registration area in which relay device 21 is currently located.

Claims

1. A method for managing location information for identifying an area in which a mobile communication device is located, the method being used in a mobile communication network serving a plurality of mobile communication devices, the method comprising:

storing, in a case that among said plurality of mobile communication devices a first master/slave relationship is established between two mobile communication devices, identification information of the device acting as a master device, which information functions as location information for the other of the two devices acting as a slave device, and storing, in a case that a mobile communication device is not currently in a dependency relation with any other of the plurality of mobile communication devices, identification information of a location registration area in which the mobile communication device is currently located, the location information being stored in a location information management device;

transmitting, from said mobile communication device acting as a master device in said first master/slave relationship to said location information management device, in a case that said first master/slave relationship should be discontinued to establish a second master/slave relationship between said mobile communication device acting as a slave device of said first master/slave relationship and another of said plurality of mobile communication devices of the network, said another device to act as a master device of said second master/slave relationship, a dependency registration change request specifying said mobile communication terminal acting as a slave device in said first master/slave relationship and said another mobile communication device to act as a master device in said second master/slave relationship; and

updating, in said location information management device, location information of said mobile communication device acting as a slave device specified in said dependency registration change request to identification information of said another mobile communication device to act as a master device of said second master/slave relationship;

wherein said mobile communication device acting as a master device in said first master/slave relationship is in a dependency relation with another of said plurality of mobile communication devices to establish a third master/slave relationship, and said mobile communication device acting as a slave device in said first master/slave relationship is in a dependency relation with the mobile communication device acting as a master device in said third master/slave relationship and acts as a slave device in said second master/slave relationship.

2. The method according to claim 1, wherein a plurality of first master/slave relationships is established, the master device being a single mobile communication device within said plurality of first master/slave relationships,

the method further comprising:

in a case that said plurality of first master/slave relationships should be discontinued to establish a plurality of second master/slave relationships, the master device being a single mobile communication device within said plurality of second master/slave relationships,

transmitting a dependency registration change notification from said single mobile communication device acting as a master device in said plurality of first master/slave relationships, to all of a plurality of mobile communication devices acting as slave devices corresponding to said plurality of first master/slave relationships, said dependency registration change notification specifying said single mobile communication device to act as a master device in said second master/slave relationships; and

wherein said dependency registration change request specifies said all of a plurality of mobile communication devices acting as slave devices in said plurality of first master/slave relationships and said single mobile communication device to act as a master device in said plurality of second master/slave relationships.

3. The method according to claim 1, wherein a plurality of first master/slave relationships is established, the master device being a single mobile communication device within said plurality of first master/slave relationships,

the method further comprising:

in a case that said plurality of first master/slave relationships should be discontinued to establish a plurality of second master/slave relationships, the master device being a single mobile communication device within said plurality of second master/slave relationships,

transmitting a dependency registration change notification from said single mobile communication device acting as a master device in said plurality of first master/slave relationships, to all of a plurality of mobile communication devices acting as slave devices corresponding to said plurality of first master/slave relationships, said dependency registration change notification indicating the change of dependency registration; and

wherein said dependency registration change request specifies among said all of a plurality of mobile communication devices, mobile communication devices which have responded to said dependency registration change notification and said single mobile communication device to act as a master device in said plurality of second master/slave relationships.

4. The method according to claim 1, wherein a plurality of first master/slave relationships is established, the master device being a single mobile communication device within said plurality of first master/slave relationships,

the method further comprising:

in a case that said plurality of first master/slave relationships should be discontinued to establish a plurality of second master/slave relationships, the master device being a single mobile communication device within said plurality of second master/slave relationships,

transmitting a dependency registration change notification indicating the change of dependency registration from said single mobile communication device acting as a master device in said plurality of first master/slave relationships, said dependency registration change notification specifying one or more of a plurality of mobile communication devices acting as slave devices corresponding to said plurality of first master/slave relationships; and

wherein said dependency registration change request specifies said one or more of a plurality of mobile communication devices acting as slave devices and said single mobile communication device to act as a master device in said plurality of second master/slave relationships.

5. The method according to claim 1,

wherein said mobile communication device acting as a master device in said first master/slave relationship is a first relay device installed in a first moving object, and a mobile communication device which is in a dependency relation with said mobile communication device acting as a master device in said first master/slave relationship is a mobile communication terminal moving to a new place with said first relay device, said mobile communication terminal being accommodated in said first moving object;

and

wherein said another mobile communication device to act as a master device in said second master/slave relationship is a second relay device installed in a second moving object, and a mobile communication device which is in a dependency relation with said another mobile, communication device to act as a master device in said second master/slave relationship is a mobile communication terminal moving to a new place with said second relay device, said mobile communication terminal being accommodated in said second moving object.

6. A relay device installed in a moving object capable of transporting a mobile communication device, comprising:

communication means for performing communications with a location information management device which stores as location information of said relay device, identification information for identifying a location registration area where said relay device is currently located and which stores as location information of said mobile communication device between two mobile communication devices, identification information of the device acting as a master device, which information functions as location information for the other of the two devices acting as a slave device, and storing, in a case that a mobile communication device is not currently in a dependency relation with any other of the plurality of mobile communication devices, identification information of a location registration area in which the mobile communication device is currently located; and

control means for, in a case that said first master/slave relationship should be discontinued to establish a second master/slave relationship between said mobile communication device acting as a slave device in said first master/slave relationship and another of said plurality of mobile communication devices of the network, said another device to act as a master device in said second master/slave relationship, controlling said location information management device to update location information of a mobile communication device acting as a slave device specified in a dependency registration change request, to identification information of said another mobile communication device to act as a master device in said second master/slave relationship in the case of receiving said dependency registration change request from said mobile communication device acting as a master device in said first master/slave relationship, said request specifying said mobile communication device to be a slave device in said first master/slave relationship and said another communication device to act as a master device in said second master/slave relationship;

said mobile communication device acting as a master device in said first master/slave relationship is in a dependency relation with another of said plurality of mobile communication devices to establish a third master/slave relationship, and said mobile communication device acting as a slave device in said first master/slave relationship is in a dependency relation with the mobile communication device acting as a master device in said third master/slave relationship and acts as a slave device in said second master/slave relationship.

7. A location information management device for managing location information which identifies an area in which a mobile communication device is located, the device being provided in a mobile communication network serving a plurality of mobile communication devices, comprising:

memory storage means for storing said location information of each one of said plurality of mobile communication devices, said memory storage means storing, in a case that among said plurality of mobile communication devices a first master/slave relationship is established in a mobile communication network serving a plurality of mobile communication devices and comprising;

(a) memory storage means for storing said location information of each one of said plurality of mobile communication devices, said memory storage means storing, in a case that among said plurality of mobile communication devices a first master/slave relationship is established between two mobile communication devices, identification information of the device acting as a master device, which information functions as location information for the other of the two devices acting as a slave device, and storing, in a case that a mobile communication device is not currently in a dependency relation with any other of the plurality of mobile communication devices, identification information of a location registration area in which the mobile communication device is currently located; and

(b) control means for, in a case that said first master/slave relationship should be discontinued to establish a second master/slave relationship between said mobile communication device acting as a slave device in said first master/slave relationship and another of said plurality of mobile communication devices of the network, said another device to act as a master device in said second master/slave relationship, controlling said location information management device to update location information of a mobile communication device acting as a slave device specified in a dependency registration change request, to identification information of said another mobile communication device to act as a master device in said second master/slave relationship in the case of receiving said dependency registration change request from said mobile communication device acting as a master device in said first master/slave relationship, said request specifying said mobile communication device to be a slave device in said first master/slave relationship and said another communication device to act as a master device in said second master/slave relationship; and

a plurality of mobile communication devices which performs communications with said location information management device,

wherein said mobile communication device acting as a master device in said first master/slave relationship is in a dependency relation with another of said plurality of mobile communication devices to establish a third master/slave relationship, and said mobile communication device acting as a slave device in said first master/slave relationship is in a dependency relation with the mobile communication device acting as a master device in said third master/slave relationship and acts as a slave device in said second master/slave relationship.

8. A mobile communication system comprising:

a location information management device for managing location information which identifies an area in which a mobile communication device is located, the device being provided transported in said moving object, identification information for identifying said relay device, thereby to subordinate said mobile communication device to said relay device; and

control means for, in a case that a first master/slave relationship between said relay device and said mobile communication device should be discontinued to establish a second master/slave relationship between said mobile communication device and another of a plurality of mobile communication devices served by a mobile communication network, said another device to act as a master device, controlling said relay device to transmit a dependency registration change request specifying the mobile communication device acting as a slave device in said first master/slave relationship and said another mobile communication device to act as a master device in said second master/slave relationship, thereby to change said identification information of said relay device acting as a master device in said first master/slave relationship, to identification information of said another mobile communication device to act as a master device in said second master/slave relationship, said identification information of said relay device being stored in said location information management device as location information of said mobile communication device acting as a slave device;

wherein said mobile communication device acting as a master device in said first master/slave relationship is in a dependency relation with another of said plurality of mobile communication devices to establish a third master/slave relationship, and said mobile communication device acting as a slave device in said first master/slave relationship is in a dependency relation with the mobile communication device acting as a master device in said third master/slave relationship and acts as a slave device in said second master/slave relationship.