Router and mobile communication terminal for mobile communication network

• US 7,277,708 B2
• Filed: 04/19/2002
• Issued: 10/02/2007
• Est. Priority Date: 01/29/2002
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kato, Tsuguo, Nakatsugawa, Keiichi
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US10/125,806
• Publication Number:
  US 20030144001A1
• Time in Patent Office: 1,992 Days
• Field of Search: 455/436, 455/437, 455/440, 455/442, 455/443, 455/456.1, 455/456.5, 455/456.6, 455/574, 455/343.1, 455/552.1, 455/524, 455/525, 370/331, 370/332, 370/333
• US Class Current: 455/437
• CPC Class Codes: H04B 7/15528 Control of operation parameters of a relay station to exploit the physical medium
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04W 36/0019 adapted for mobile IP [MIP]
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/005 Data network PoA devices
• CPC Class Codes: H04W 88/14 Backbone network devices

Abstract

The present invention provides a mobile communication network system comprising a first mobile communication network having a plurality of routers, a second mobile communication network having a plurality of routers, and a mobile communication terminal. A router located in an end section of a communication area of the first mobile communication network sends an end message indicating that it is located in the end section, to the mobile communication terminal. The terminal initiates communications with a router of the second mobile communication network, whilst the terminal is communicating with the router located in the end section, upon receiving the end message sent by the router located in the end section.

Claims

1. A mobile communication terminal comprising:

a first communication unit for performing radio communications with at least one of a plurality of routers provided in a first mobile communication network;

a second communication unit for performing radio communications with at least one of a plurality of routers provided in a second mobile communication network; and

a control unit for controlling said second communication unit so that said second communication unit initiates communications with said router provided in said second mobile communication network, whilst said first communication unit is communicating with a router located in an end section of a communication area of said first mobile communication network, upon receiving a message sent by said router located in said end section, said message indicating that said router is located in the end section.

2. The mobile communication terminal according to claim 1, wherein said control unit switches off power supplied to said second communication unit until said first communication unit receives said message, and switches on the power supplied to said second communication unit, when said first communication unit receives said message.

3. A mobile communication network system comprising a first mobile communication network having a plurality of routers, a second mobile communication network having a plurality of routers, and a mobile communication terminal;

wherein, of the plurality of routers of said first mobile communication network, a router located in an end section of a communication area of said first mobile communication network comprises a transmission unit for sending an end message indicating that it is located in the end section of said communication area, to said mobile communication terminal, and

said mobile communication terminal comprises;

a first communication unit for performing radio communications with at least one of the plurality of routers of said first mobile communication network;

a second communication unit for performing radio communications with at least one of the plurality of routers provided in said second mobile communication network; and

a control unit for controlling said second communication unit so that said second communication unit initiates communications with said router provided in said second mobile communication network, whilst said first communication unit is communicating with the router located in the end section of the communications area of said first mobile communication network, upon receiving the end message sent by said router located in said end section.

4. A communication method in a mobile communication network system comprising a first mobile communication network having a plurality of routers, a second mobile communication network having a plurality of routers, and a mobile communication terminal, comprising steps of:

in a router located in an end section of a communication area of said first mobile communication network, of the plurality of routers of said first mobile communication network, sending an end message indicating that said router is located in the end section of said communication area, to said mobile communication terminal; and

in said mobile communication terminal, initiating communications with a router provided in said second mobile communication network, whilst said mobile communication terminal is communicating with the router located in the end section of the communication area of said mobile communication, upon receiving said end message sent by said router located in said end section.