Accession Number : AD0869941

Title :   Coding for Turbulent Channels. Volume I. Summary.

Descriptive Note : Final technical rept.,

Corporate Author : GENERAL ELECTRIC CO SYRACUSE NY HEAVY MILITARY ELECTRONIC SYSTEMS

Personal Author(s) : Mitchell, M. E. ; Stutt, C. A. ; Colley, L. E.

Report Date : APR 1970

Pagination or Media Count : 22

Abstract : A 3-Mbps, 4-frequency, 2-phase, differentially keyed, adaptive-bias, decision-controlled modem operating over a tropo-scatter path of 175 miles at a frequency of 850 MHz with 10-MHz bandwidth and 28-foot antennas was simulated. Tape recordings derived from the simulation were analyzed, and the results were used as a basis for evaluating proposed coding techniques for turbulent tropo-scatter channels. A small number of potentially applicable coding techniques were investigated in detail, and a class of preferred coding techniques for turbulent channels was identified. General performance equations were derived for the class of binary group codes, including both exact and approximate formulas for computing the probability of digit and word error after decoding. The results of a direct experimental measurement of the performance of an example coding technique on a turbulent telephone channel are presented and interpreted. (Author)

Descriptors :   *CODING), (*PULSE COMMUNICATIONS, DATA TRANSMISSION SYSTEMS, L BAND, DECODING, TROPOSPHERE, TELEPHONE SYSTEMS, SIMULATION, DIGITAL SYSTEMS, DEMODULATORS, ERRORS.

Subject Categories : Cybernetics
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE