System for determining and registering location of mobile terminal for communication system with non-geosynchronous satellites

• US 5,543,813 A
• Filed: 07/29/1994
• Issued: 08/06/1996
• Est. Priority Date: 08/12/1993
• Status: Expired due to Fees

• Current Assignee: KDDI Corporation
• Original Assignee: Kokusai Densin Denwa Kabushiki Kaisha
• Inventors: Shinonaga, Hideyuki, Araki, Noriyuki, Itoh, Yasuhiko
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): PHAN, DAO LINDA
• Application Number:
  US08/282,309
• Time in Patent Office: 739 Days
• Field of Search: 342/352, 342/357, 455/12.1, 364/459
• US Class Current: 342/357.2
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/0295 Proximity-based methods, e.g. position inferred from reception of particular signals
• CPC Class Codes: H04B 7/18545 Arrangements for managing station mobility, i.e. for station registration or localisation

Abstract

The non-geosynchronous orbiting satellites each transmit identification information given to each of spot beams irradiated from them. A mobile terminal, when registering its location, receives the spot beam identification information at some moments in time with the predetermined time interval. Then, the mobile terminal transmits the received spot beam identification information and each of their reception time together with the terminal identification information assigned to the mobile terminal. On the basis of an overlapped area of spot beam coverage areas at time when each of identification information is received by the terminal, a terrestrial network estimates and registers the latest location of the mobile terminal.

Claims

1. A system for determining and registering the location of a mobile terminal for a communication system with non-geosynchronous satellites wherein:

a plurality of non-geosynchronous satellites are disposed and a plurality of land earth stations are disposed on the earth;

each of said satellites irradiates a spot beam to its satellite coverage area on the earth where mobile terminals can communicate with the satellite, or each of said satellites irradiates a spot beam to each of a plurality of smaller areas into which said satellite coverage areas is divided, through which spot beams said satellite can communicate with said mobile terminals in said satellite coverage area;

identification information given to each of said spot beams is transmitted through each of said spot beams;

said mobile terminal, when registering its location, receives said spot beam identification information at a plurality of moments in time, said mobile terminal transmits, via said satellite, at a plurality of sets of information including received spot beam identification information and information on reception time of each spot beam identification information; and

an overlapped area of a plurality of spot beam coverage areas at the time when each of said spot beam identification information is received at said mobile terminal, is used as the location information of said mobile terminal.

2. A system for determining and registering the location of a mobile terminal for a communication system with non-geosynchronous orbiting satellites wherein:

a plurality of non-geosynchronous satellites are disposed and a plurality of land earth stations are disposed on the earth;

each of said satellites irradiates a spot beam to its satellite coverage area on the earth where mobile terminals can communicate with the satellite, or each of said satellites irradiates a spot beam to each of a plurality of smaller areas into which said satellite coverage area is divided, through which spot beams said satellite can communicate with said mobile terminals in said satellite coverage area;

identification information given to each of said spot beams is transmitted through each of said spot beams;

said mobile terminal, when registering its location, receives a plurality of said spot beam identification information at the same time, and transmits, via said satellite, said received spot beam identification information and information on time when said mobile terminal received said spot beam identification information; and

an overlapped area of a plurality of spot beam coverage areas at the time when a plurality of sets of spot beam identification information are received at said mobile terminal, is used as the location information of said mobile terminal.