New emergency beacon similar to conventional one, except modulation interrupted periodically while unmodulated carrier is transmitted. Modulation scheme for emergency radio beacons aids searchers by indicating kind of vehicle in distress. Transmitted signal similar to present standard signal of emergency locator transmitters (ELT's) and emergency position-indicating radio beacons (EPIRB's) but also includes periods of unmodulated carrier.
Emergency-Radio Modulation Would Identify Type of Vehicle
NASA Tech Briefs ; 11 , 5
1987-05-01
Sonstige
Keine Angabe
Englisch
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