Satellite-based vehicle position determining system
Patent 4359733 Issued on November 16, 1982. Estimated Expiration Date: 
September 23, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 23, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorApplicationNo. 06/189744 filed on 09/23/1980US Classes:342/36, AIR TRAFFIC CONTROL342/357.01, With position indicating342/44, Unique identity342/456, Having traffic control701/207Employing position determining equipmentExaminersPrimary: Tubbesing, T. H.Attorney, Agent or FirmInternational ClassesG01S 13/78 (20060101)G01S 13/87 (20060101) G01S 5/14 (20060101) G01S 13/00 (20060101) AbstractA system for determining the positions of a plurality of vehicles traveling on or above a defined sector of the earth's surface comprises a transponder carried by each vehicle for transmitting a uniquely coded beacon signal in response to a general interrogation signal, at least three repeater-carrying satellites at spaced orbital locations above the earth for receiving and retransmitting the beacon signals produced by the vehicles, and a ground station for periodically transmitting the general interrogation signal and for receiving and processing the beacon signals retransmitted by the three satellites in order to determine vehicle position. In order to avoid signal overlap and equipment saturation at the ground station, each vehicle transponder includes means responsive to the general interrogation signal for inhibiting the transmission of further beacon signals by the transponder for a predetermined time interval following the response of the transponder to the general interrogation signal. In a preferred embodiment of the invention, the inhibited interval of the vehicle transponders may be varied automatically in response to a command signal transmitted by the ground station.Other References
| |
