
Accession Number : AD0281751
Title : AN ACQUIRABLE CODE,
Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
Personal Author(s) : Weiss ,Edwin ; Gorenstein,Daniel
Report Date : 09 JUL 1962
Pagination or Media Count : 8
Abstract : The problem of range measurement for vehicles in space is usually treated within the following framework. At the ground one transmits continuously a single sequence of very long period. This is received at the vehicle and retransmitted. Thus, at the ground a corrupted and outofphase version of the original sequence is received. By operating on it (usually by correlation techniques) one hopes to determine the phase, and then by measuring the elapsed time to find the distance in question (without ambiquity in virtue of the long period of the sequence). Such a sequence is known as an acquirable code. An elegant (though elementary) mathematical procedure is described for selecting an acquirable code; it rests on wellknown properties of maximal length shift register sequences and on the Chinese Remainder Theorem. (Author)
Descriptors : *ALGEBRA, *CORRELATION TECHNIQUES, *PHASE MEASUREMENT, *RADAR SIGNALS, *RANGES (DISTANCE)
Distribution Statement : APPROVED FOR PUBLIC RELEASE