Accession Number : AD0726101

Title :   Subsequence Sync Design.

Descriptive Note : Final technical rept. Mar-Nov 70,

Corporate Author : RAYTHEON CO SUDBURY MASS EQUIPMENT DIV

Personal Author(s) : Turyn,Richard J. ; Herman,Jan

Report Date : JUN 1971

Pagination or Media Count : 49

Abstract : The report is concerned with the determination of the phase of a binary sequence whose rule of formation is known but which has been received with errors. It is desired to determine the phase from a relatively short sequence. The authors describe what they call a predictive correlator, which represents a new approach to the correlation problem. It allows decisions on the phase of the incoming sequence in a much shorter tme and with much simpler equipment than a conventional correlator, with better probability of success. Although the emphasis is on the m-sequences the idea is applicable to any binary sequence. The authors present the design of a predictive correlator, which would operate at a 10 nanosecond rate, and of all equipment which would be necessary for a laboratory demonstration of the feasibility of the scheme. In addition, the report discusses some results on the statistics of the weights of subsequences of an m-sequence. It is shown that the predictive correlator will provide synchronization on subsequences of length 500 for an m-sequence of length ((2 to the 23rd power)-1) with probability of missed synchronization and false synchronization more than two orders of magnitude less than the probability of error of the input pulses. (Author)

Descriptors :   (*INFORMATION THEORY, PHASE MEASUREMENT), (*PULSE COMMUNICATIONS, *SYNCHRONIZATION(ELECTRONICS)), FEASIBILITY STUDIES, SHIFT REGISTERS, CORRELATION TECHNIQUES, PROBABILITY, SEQUENCES(MATHEMATICS), CODING

Subject Categories : Cybernetics
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE