Accession Number : ADD015325
Title : Transmitter Location System for Frequencies Below HF.
Descriptive Note : Patent, Filed 26 Apr 72, patented 17 Dec 91,
Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC
Personal Author(s) : Westfall, Wallace D
Report Date : 17 Dec 1991
Pagination or Media Count : 7
Abstract : Differential phase measurement techniques and apparatus for accurately locating unknown transmitters over great distances at radio frequencies below HF. A network of separated, time- and phase-synchronized, pairs of receiving stations having vertical whip antennas and having a known base-line geometry with respect to each other are used to accurately measure VLF phase differentials. The measured phase differences are compared against theoretical calculated values to provide highly accurate transmitter location information.
Descriptors : *PATENTS, *RADIO DIRECTION FINDERS, BASE LINES, GEOMETRY, NETWORKS, PHASE MEASUREMENT, STATIONS, TIME, WHIP ANTENNAS, RADIO TRANSMITTERS
Subject Categories : Direction Finding
Distribution Statement : APPROVED FOR PUBLIC RELEASE