
Accession Number : ADA298808
Title : Coding and Synchronization Analysis of the NILE UHF FixedFrequency Waveform.
Descriptive Note : Interim rept. MarMay 95,
Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC
Personal Author(s) : Crepeau, Paul J. ; McCanless, John C.
PDF Url : ADA298808
Report Date : 18 SEP 1995
Pagination or Media Count : 18
Abstract : The NILE UHF fixed frequency waveform employs an RS (48,30) error control code with 8bit characters. The code is used both to correct errors and to identify when the decoder has failed to produce a correct codeword. When this code is used on a memoryless binary symmetric channel, the probability of codeword error is 10(exp5) when the channel bit error probability is 0.5%, and the probability of undetected decoder error is upper bounded by 2.8 (106) for all channel bit error probabilities. Synchronization acquisition, employing a 255bit reference sequence, is far more tolerant to bit errors than the waveform itself. The probability of false synchronization in a random noise environment is less than 10(exp6) when the correlator threshold is set at 90. With this threshold the probability of missed synchronization is less than 10(exp6) for a 20% channel bit error probability. Synchronization performance is acceptable for truncated received sequences up to truncation levels of 50%.
Descriptors : *WAVEFORMS, *CODING, *SYNCHRONIZATION(ELECTRONICS), CONTROL, THRESHOLD EFFECTS, PROBABILITY, ERRORS, CHANNELS, ERROR CORRECTION CODES, ULTRAHIGH FREQUENCY, DECODERS, TRUNCATION, CORRELATORS.
Subject Categories : Radio Communications
Distribution Statement : APPROVED FOR PUBLIC RELEASE