Mobile satellite communication system

• US 5,528,247 A
• Filed: 06/07/1994
• Issued: 06/18/1996
• Est. Priority Date: 07/07/1993
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Nonami, Takayuki
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): PHAN, DAO LINDA
• Application Number:
  US08/255,963
• Time in Patent Office: 742 Days
• Field of Search: 342/357, 455/12.1, 455/33.1, 455/54.1
• US Class Current: 342/357.64
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: H04B 7/18552 using a telephonic control signal and a second ranging satellite determining absolute distances from a plurality of spaced points of known location G01S5/14

Abstract

The present invention relates to a mobile satellite communication system. It is the object of the invention to provide a mobile satellite communication system capable of monitoring a location of a mobile station by data on its absolute location on the ground L, in lieu of relative monitoring thereof with respect to satellite base stations, to thereby ensure an effective location registration and suppress an increase of traffic in communication lines arising from location registrations. The satellite base stations are each equipped with a navigation signal generator for issuing navigation signals. The mobile station detects its absolute location on the ground L based on the navigation signals received from the satellite base stations, and executes its location registration procedure by use of identification data (communication zone ID) associated with the communication zone in which it lies and which is determined by the thus detected absolute location data.

Claims

1. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground; and

(b) a plurality of satellite base stations each moving along its orbit round the earth and communicable with said mobile station located within its service area;

said mobile station including;

(c) a registration means which detects its absolute location on the earth based on communication signals from said satellite base stations and registers thus detected its absolute location into a system monitor section;

(d) a memory means for storing, as its location data, one of identification data corresponding to communication zones which are allocated in advance on the ground;

(e) a location detection means for detecting its absolute location on the Earth, based on signals from said satellite base stations;

(f) a zone decision means for determining which communication zone it lies in of all of said communication zones, based on an output from said location detection means; and

(g) a location registration means which, if the determined communication zone is not coincident with the communication zone associated with the identification data now being stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said determined communication zone.

2. A mobile satellite communication system according to claim 1, wherein

said mobile station further comprises:

(h) an update means which, if said determined communication zone is not coincident with said communication zone associated with said identification data now being stored, updates said identification data being stored into the identification data corresponding to said determined communication zone.

3. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground;

(b) a plurality of satellite base stations each moving along its orbit round the Earth and communicable with said mobile station located within its service area; and

(c) a plurality of switching centers placed on the ground and constituting a communication network in cooperation with said satellite base stations;

said plurality of satellite base stations each including

(d) a transmitter means for transmitting communication signals containing its absolute location data on its orbit round the Earth;

said mobile station including;

(e) a memory means for storing, as its location data, one of identification data corresponding to communication zones which are allocated in advance on the Ground;

(f) a location detection means for detecting its absolute location on the Earth, based on signals from said satellite base stations;

(g) a zone decision means for determining which communication zone it lies in of all of said communication zones, based on an output from said location detection means;

(h) a location registration means which, if the determined communication zone is not coincident with the communication zone associated with the identification data now being stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said determined communication zone; and

(i) an update means which, if said determined communication zone is not coincident with said communication zone associated with said identification data now being stored, updates said identification data being stored into the identification data corresponding to said determined communication zone.

4. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground;

(b) a plurality of satellite base stations each moving along its orbit round the earth and communicable with said mobile station located within its service area; and

(c) a GPS satellite;

said mobile station including;

(d) a registration means which detects its absolute location on the earth based on communication signals from said satellite base stations and registers thus detected its absolute location in a system monitor section;

(e) a memory means for storing, as its location data, one of identification data corresponding to communication zones which are allocated in advance on the ground;

(f) a location detection means for detecting its absolute location on the Earth, based on signals from said satellite base stations;

(g) a zone decision means for determining which communication zone it lies in of all of said communication zones, based on an output from said location detection means; and

(h) a location registration means which, if the determined communication zone is not coincident with the communication zone associated with the identification data now being stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said determined communication zone.

5. A mobile satellite communication system according to claim 4, wherein

said mobile station further comprises:

(i) an update means which, if said determined communication zone is not coincident with said communication zone associated with said identification data now being stored,

updates said identification data being stored into the identification data corresponding to said determined communication zone.

6. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground;

(b) a plurality of satellite base stations each moving along its orbit round the Earth and communicable with said mobile station located within its service area;

(c) a plurality of switching centers placed on the ground and constituting a communication network in cooperation with said satellite base stations; and

(d) a GPS satellite;

said mobile station including;

(e) a memory means for storing, as its location data, one of identification data corresponding to communication zones which are allocated in advance on the ground;

(f) a location detection means for detecting its absolute location on the Earth, based on signals from said satellite base stations;

(g) a zone decision means for determining which communication zone it lies in of all of said communication zones, based on an output from said location detection means;

(h) a location registration means which, if the determined communication zone is not coincident with the communication zone associated with the identification data now being stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said determined communication zone; and

(i) an update means which, if said determined communication zone is not coincident with said communication zone associated with said identification data now being stored, updates said identification data being stored into the identification data corresponding to said determined communication zone.

7. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground;

(b) a plurality of satellite base stations each moving along its orbit round the Earth and communicable with said mobile station located within its service area; and

(c) a plurality of switching centers placed on the ground and constituting a communication network in cooperation with said satellite base stations;

said plurality of switching centers each including;

(d) an identification data transmitter means for transmitting identification data corresponding to communication zone in which it lies;

said switching centers being provided individually corresponding to said communication zones;

said satellite base stations each including;

(e) an identification data transmitter means which, if service area of said satellite base station is located within one of said communication zones, transmits identification data received from said switching center placed in said one of said communication zones to said mobile station lying within said one of said communication zones;

said mobile station including;

(f) a registration means which detects a communication zone in which it lies based on communication signals containing said identification data from said satellite base stations and registers thus detected communication zone in which it lies into a monitor system;

(g) a memory means for storing as its location data, one of identification data corresponding to said communication zones;

(h) a zone detection means for detecting a communication zone in which it lies based on identification data from said satellite base stations; and

(i) a location registration means which, if the detected communication zone is not coincident with the communication zone associated with the identification data now being stored, loads into a system a location registration for permitting its location to be accessed, by use of the identification data corresponding to said detected communication zone.

8. A mobile satellite communication system according to claim 7, wherein

said mobile stations further comprising:

(j) an update means which, if the detected communication zone is not coincident with the communication zone associated with the identification data now being stored, updates said identification data being stored into the identification data corresponding to said detected communication zone.

9. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground; and

(b) a plurality of satellite base stations each moving along its orbit round the Earth and communicable with said mobile station located within its service area;

said mobile stations including;

(c) a registration means which detects a terrestrial communication zone in which it lies based on zone identification data from a switching center of a terrestrial mobile communication system provided on each of terrestrial communication zones which are allocated in advance in the terrestrial mobile communication system, and which informs a system monitor section of a location in which it lies by use of its identification data;

(d) a memory means for storing, as its location data, one of identification data corresponding to terrestrial communication zones which are allocated in advance on the ground in said terrestrial mobile communication system;

(e) a zone detection means for detecting a terrestrial communication zone in which it lies, based on zone identification data from a switching center of said terrestrial mobile communication system provided on each of said terrestrial communication zones; and

(f) a location registration means which, if the detected terrestrial communication zone is not coincident with the terrestrial communication zone associated with the identification data now being stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said detected terrestrial communication zone.

10. A mobile satellite communication system according to claim 9, wherein

said mobile station further comprises:

(g) an update means which, if the detected terrestrial communication zone is not coincident with the terrestrial communication zone associated with the identification data now being stored, updates said identification data being stored into the identification data corresponding to said detected terrestrial communication zone.

11. A mobile satellite communication system comprising:

(a) a mobile station movable on the ground;

(b) a plurality of satellite base stations each moving along its orbit round the Earth and communicable with said mobile station located within its service area; and

(c) a plurality of earth switching centres placed on the ground and constituting a communication network in cooperation with said satellite base stations;

said mobile stations including;

(d) a memory means for storing, as its location data, one of identification data corresponding to terrestrial communication zones which are allocated in advance on the ground in said terrestrial mobile communication system;

(e) a zone detection means for detecting a terrestrial communication zone in which it lies, based on zone identification data from a switching center of said terrestrial mobile communication system provided on each of said terrestrial communication zones;

(f) a location registration means which, if the detected communication zone is not coincident with the terrestrial communication zone associated with the identification data being now stored, loads into a system monitor section a location registration for permitting its location to be accessed, by use of the identification data corresponding to said detected terrestrial communication zone; and

(g) an update means which, if the detected terrestrial communication zone is not coincident with the terrestrial communication zone associated with the identification data now being stored, updates said identification data being stored into the identification data corresponding to said detected terrestrial communication zone.

12. A location registration method for registering data on the location of a mobile station into a monitor section of a mobile satellite communication system, comprising the steps of:

(a) causing a mobile station to detect its absolute location on the earth based on communication signals from a plurality of satellite base stations; and

(b) registering thus detected absolute location into said monitor section;

wherein said step (b) includes the steps of;

(b1) judging which communication zone it lies in of communication zones which are allocated in advance on the ground, based on its absolute location detected in said step (a);

(b2) comparing said communication zone judged in said step (b1) with a communication zone being previously stored; and

(b3) if said judged communication zone is different from said communication zone being stored, registering its location into said monitoring section by use of identification data associated with said judged communication zone.

13. A location registration method according to claim 12, wherein

said step (b) further includes the step of:

(b4) updating said stored communication zone into said judged communication zone.

14. A location registration method for registering data of the location of a mobile station into a monitor section of a mobile satellite communication system, comprising the steps of:

(a) causing said mobile station to detect its absolute location on the earth based on signals from a plurality of GPS satellites; and

(b) registering thus detected absolute location into said monitor unit;

wherein said step (b) includes the steps of;

(b1) judging which communication zone it lies in of communication zones which are allocated in advance on the ground, based on its absolute location detected in said step (a);

(b2) comparing said communication zone judged in said step (b1) with a communication zone being previously stored; and

(b3) if said judged communication zone is different from said communication zone being stored, registering its location into said monitoring section by use of identification data associated with said judged communication zone.

15. A location registration method according to claim 14, wherein

said step (b) further includes the step of:

(b4) updating said stored communication zone into said judged communication zone.

16. A location registration method for registering data on the location of a mobile station into a monitor section of a mobile satellite communication system, comprising the steps of:

(a) causing a switching center to transmit identification data associated with a communication zone in which it lies to a plurality of satellite base stations;

(b) causing each of said satellite base stations to transmit said identification data received to a mobile station lying within a communication zone which it serves;

(c) causing said mobile station to receive said identification data transmitted from said satellite base stations to detect its communication zone;

(d) causing said mobile station to register the communication zone detected in said step (c) into said monitor section;

wherein said step (d) includes the steps of;

(d1) comparing its communication zone detected in said step (c) with a communication zone being previously stored; and

(d2) if said detected communication zone is different from said stored communication zone, registering its location into said monitor section by using identification data associated with said detected communication zone.

17. A location registration method according to claim 16, wherein said step (d) further includes the step of:

(d3) updating said stored communication zone into said detected communication zone.

18. A location registration method for registering data on the location of a mobile station into a monitor section of a mobile satellite communication system, comprising the steps of:

(a) causing said mobile station to detect a terrestrial communication zone in which it lies based on signals from a switching center provided on each of terrestrial communication zones which are allocated in advance on the ground in a terrestrial mobile communication system; and

(b) registering its location into said monitor section by use of identification data associated with detected communication zone;

wherein said terrestrial mobile communication system in said step (a) is a cellular system and wherein said step (b) includes the steps of;

(b1) comparing its terrestrial communication zone detected in said step (a) with the terrestrial communication zone being previously stored; and

(b2) if said detected terrestrial communication zone is different from said stored terrestrial communication zone, registering its location into said monitor section by use of identification data associated with said detected terrestrial communication zone.

19. A location registration method according to claim 18, wherein said step (b) further includes the step of:

(b3) updating said stored terrestrial communication zone into said detected terrestrial communication zone.