04494119 is referenced by 225 patents and cites 16 patents.

A dedicated distress radiolocation system combines direction-finding techniques with calculations based on signal strength to precisely locate a distress transmission and effect rescue of the person or property in distress. The system is capable of locating a distress transmission solely on the basis of a short duration pulse; however, for identification purposes and for communication reliability a series of pulses is transmitted. The system includes distress transmitters, a plurality of slave repeater units at known locations to receive the distress transmission and report their signal strength to a central station, a central station to calculate the distress transmitter's location based on the measured signal strengths and the known locations of the repeater units and to dispatch a rescue unit, and rescue units equipped with direction finding equipment to approach the distress transmitter. Most actions of the system are undertaken automatically.

Title
Distress radiolocation method and system
Application Number
6/520327
Publication Number
4494119
Application Date
August 4, 1983
Publication Date
January 15, 1985
Inventor
Fred Wimbush
Toronto
CA
Agent
Banner Birch McKie & Beckett
Assignee
122923 Canada
CA
IPC
G01S 5/02
H04B 7/185
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