Single frequency radio ranging system
Patent 4011562 Issued on March 8, 1977. Estimated Expiration Date: 
March 8, 1994. 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.
March 8, 1994. 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 References 2546973 2890449 3742496 3860921 3900847 InventorAssigneeApplicationNo. 05/560339 filed on 03/21/1975US Classes:342/46, Navigational342/125With remote cooperating stationExaminersPrimary: Hubler, Malcolm F.Attorney, Agent or FirmAbstractA precision radio ranging system that uses primarily a single carrier frequency interrogating and responding signal that is pulse amplitude modulated to provide phase shift information. A mobile interrogator finds its position by measuring ranges to each of two fixed responders. During a measurement, the interrogator has sole usage of the responder and transmits a pulse of a single frequency RF carrier. The responder measures the received carrier phase and later transmits a reply pulse on the same single frequency RF carrier which replicates this phase. The interrogator determines range to the responder from the phase difference of its own interrogation pulse and the responder reply pulse. In multiple system use, two closely spaced carrier frequencies may be time sequenced to provide multiparty two range service. | |
