MOBILE COMMUNICATION SYSTEM

• US 3,663,762 A
• Filed: 12/21/1970
• Issued: 05/16/1972
• Est. Priority Date: 12/21/1970
• Status: Expired due to Term

• Current Assignee: Amos Edward Jr. Joel
• Original Assignee: Amos Edward Jr. Joel
• Inventors: Joel, Amos Edward Jr.
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Leaheey, Jon Bradford
• Application Number:
  US05/099,926
• Time in Patent Office: 512 Days
• Field of Search: 179/41A 325/51,53,54,111
• US Class Current: 455/440
• CPC Class Codes: H04W 36/08 Reselecting an access point

Abstract

A high capacity cellular mobile communication system arranged to establish and maintain continuity of communication paths to mobile stations passing from the coverage of one radio transmitter into the coverage of another radio transmitter. A control center determines mobile station locations and enables a switching center to control dual access trunk circuitry to transfer an existing mobile station communication path from a formerly occupied cell to a new cell location. The switching center subsequently enables the dual access trunk to release the call connection to the formerly occupied cell.

Claims

1. In a communication system a plurality of mobile stations, a plurality of base stations each located in a designated cell area and each comprising apparatus for defining channels for communicating with said mobile stations, means common to said base stations for ascertaining locations of designated ones of said mobile stations in any of said cell areas, means activated by said ascertaining means in accordance with said locations of said designated mobile stations for establishing connections to said base stations and said channels to provide communication paths to said designated mobile stations, means for periodically monitoring said communication paths to determine changes of locations of said designated mobile stations, and means activated by said monitoring means in accordance with a change of locations of one of said designated mobile stations for causing said connection establishing means to rearrange the connection of said base stations and said channels for said one designated mobile station to continuously maintain said communication paths.

2. In a communication system the invention defined in claim 1 wherein said ascertaining means comprises first means individual to each of said base stations for communicating with said designated mobile stations while said designated mobile stations are within the area designated by said base station, second means individual to each said base station for communicating with said designated mobile stations when said designated mobile stations are outside the area designated by said base station, and means operative by both said first and said second communicating means for determining the area locations of said designated mobile stations.

3. In a communication system the invention defined in claim 2 wherein said first communicating means for a particular one of said base stations comprises first radio means defining a signaling channel exclusive to said particular base station, wherein said second communicating means of said particular base station comprises second radio means defining said signaling channels associated with base stations adjacent to said particular base station, and wherein said determining means includes means for registering the identity of said signaling channels over which said designated mobile stations are signaling.

4. In a communication system the invention defined in claim 3 wherein said determining means comprises stored program control means common to said first and said second radio means for deriving the cell area location of said designated mobile stations from said registered channel identities.

5. In a communication system the invention defined in claim 1 wherein said connection establishing means comprises means responsive to signals from calling ones of said designated mobile stations for alerting called ones of said designated mobile stations in all of said cell areas.

6. In a communication system the invention defined in claim 1 wherein said connecting establishing means comprises communication links coupled to the base stations of said cell areas for connection to said designated mobile stations, and means common to said plurality of base stations for selectively connecting any one of said communication links to any other said communication link.

7. In a communication system the invention defined in claim 6 wherein each of said communication links comprises a channel component corresponding to an individual basE station and wherein said monitoring means comprises receiving means at each said base station for monitoring said channel components, and means at each said base station for identifying the direction from said base station of said monitored channel components over which said designated mobile stations are communicating.

8. In a communication system the invention defined in claim 7 wherein said receiving means comprises a radio receiver selectively tunable to said channel components corresponding to said base station and to said channel components corresponding to said adjacent base stations, and wherein is also provided interrogating means for periodically tuning said radio receivers to said channel components of said established communication paths.

9. In a communication system the invention defined in claim 8 wherein said identifying means at a particular one of said base stations comprises directional antenna means corresponding to said adjacent base stations, and means for generating a coded signal identifying enabled ones of said antenna means, and wherein said rearranging means comprises means for periodically registering said coded signals.

10. In a communication system the invention defined in claim 9 wherein said rearranging means further comprises means for comparing previously registered ones of said coded signals with currently registered ones of said coded signals to ascertain the movement of said designated mobile stations from first ones of said cell areas to second ones of said cell areas.

11. In a communication system the invention defined in claim 10 wherein said connection establishing means further comprises first ones of said communication links coupled to the base stations of said first cell areas for connection to said designated mobile stations, and wherein said rearranging means also comprises means responsive to said comparing means for selecting second ones of said communication links coupled to the base stations of said second cell areas for connection to said designated mobile stations, and means for transferring the connections of said designated mobile stations from said first communication links to said second communication links as said designated mobile stations change cell locations.

12. In a communication system the invention defined in claim 11 wherein said transferring means includes a trunk means comprising a line appearance terminating one of said designated mobile stations, a first trunk appearance terminating one of said first communication links, a second trunk appearance terminating one of said second communication links, and means responsive to said comparing means for selectively connecting said line appearance to said first and said second trunk appearances.

13. In a mobile communication system a plurality of mobile stations, a plurality of base stations each located in a designated cell area and each comprising apparatus for defining channels for communicating with said mobile stations, radio means individual to each of said base stations for communicating with designated ones of said mobile stations, processor means connected to said radio means for ascertaining the cell area locations of said designated mobile stations, switching means common to said base stations for establishing connections to said base station apparatus to provide communication paths on said channels to said located mobile stations, monitoring means responsive to said processor means for selecting ones of said channels to determine changes of locations of said designated mobile stations, and means located in said switching means and activated by said processor means in accordance with said changes of locations for rearranging the connections of said base station apparatus to continuously maintain said communication paths.

14. In a mobile communication system the invention defined iN claim 13 wherein said rearranging means comprises trunk means having a line appearance and dual trunk appearances selectively connectable to said base station apparatus for connecting a first one of said designated mobile stations through said line appearance to said trunk appearances connected to a second one of said designated mobile stations.

15. In a mobile communication system the invention defined in claim 14 wherein said trunk means comprises means for selectively connecting said line appearance to a first one of said trunk appearances to form one of said communication paths between said first and said second mobile stations, means activated by said processor means in accordance with a change of location of said second mobile station for directing said connecting means to couple a second one of said trunk appearances connected to one of said base station apparatus to said one communication path, means connected by said directing means to said one communication path for signaling said second mobile station to select one of said channels associated with said one base station apparatus, and means effective upon the de-activation of said directing means for enabling said connecting means to open said connection extending from said line appearance to said first trunk appearance.

16. In a mobile communication system the invention defined in claim 15 wherein said directing means comprises a magnetic latching relay operated by a first polar signal and released by a second polar signal.

17. In a mobile communication system the invention defined in claim 16 wherein said signaling means comprises channel transfer supervisory means for transmitting and receiving control signals between said trunk means and said second mobile station, and means enabled by the operation of said latching relay for coupling said supervisory means across the connection extending from said line appearance to said trunk appearances.

18. In a mobile communication system the invention defined in claim 16 wherein said signaling means comprises a filter operable to inhibit the passage of electrical signals corresponding to control signals transmitted between said signaling means and second mobile station, and means enabled by the operation of said latching relay for inserting said filter in series with the connection extending from said line appearance to said trunk appearances.

19. In a mobile communication system the invention defined in claim 16 wherein said connecting means comprises a first and second relay, a first control path enabling one of said trunk appearances and comprising break contacts of said first and said second relays, a second control path enabling the other said trunk appearance and comprising make contacts of said first and said second relays, a third control path enabling both said trunk appearances and comprising make contacts of said latching relay, a first transmission path connecting said line appearance to said enabled one trunk appearance and comprising further break contacts of said first relay connected in parallel with further break contacts of said second relay, a second transmission path connecting said line appearance to said enabled other trunk appearance and comprising further make contacts of said first relay connected in parallel with further make contacts of said second relay, and means including further make contacts of said latching relay for operating and releasing said first and said second relays.

20. In a mobile telephone communication system having a mobile station and a telephone station the combination comprising a data processor;

a plurality of base stations each located in a designated cell area and each including apparatus for defining channels for communicating with said mobile station, a plurality of transmission lines selectively connectable to said channel apparatus, a plurality of directional antennas, a radIo transmitter connected to said antennas for continuously transmitting a first signal individual to each said base station, a radio receiver connected to said antennas for receiving a second signal individual to each of said base stations from said mobile station enabled by said first signal, a plurality of monitor receivers connected to said antennas for receiving said second signal from said enabled mobile station located in adjacent cell areas, a selective receiver connected to said antennas for monitoring one of said channels selected by said data processor to detect a movement of said enabled mobile station from a first cell location to a second cell location, and a plurality of data generators connected to said monitor receivers and to said selective receiver for identifying enabled ones of said antennas;

a controller connected to said base stations and including said data processor for computing the cell location of said enabled mobile station from a plurality of antenna identifying signals received from those base stations surrounding said enabled mobile station;

a first switching network activated by said controller in accordance with said first cell location for connecting a first one of said channel apparatus to a first one of said transmission lines;

a switching office connected to said transmission lines and activated by dialing signals received from said enabled mobile station on said first transmission line for connecting said first transmission line to said telephone station to form a communication path between said enabled mobile station and said telephone station;

a second switching network activated by said controller in accordance with said second cell location for connecting a second one of said channel apparatus to a second one of said transmission lines; and

means located in said switching office and activated by said controller in accordance with change of location signals from said processor for transferring the connection between said mobile station and said telephone station from said first transmission line to said second transmission line to continuously maintain said communication path.