Accession Number : AD0286504

Title :   STUDY OF ADAPTABLE COMMUNICATIONS SYSTEMS

Corporate Author : SYLVANIA ELECTRIC PRODUCTS INC WALTHAM MASS

Personal Author(s) : CHESLER,D.

Report Date : 14 JUN 1962

Pagination or Media Count : 1

Abstract : Studies on adaptable communication systems are reported, covering both adaptable receivers and repeat-request feedback systems using error-detection codes. The study on error-detecting codes deals with a multi-stage error-detection repeat-request system in which the receiver performs error detection on small blocks of binary digits and requests a repeat of each block in which an error is detected. It is shown that even with feedback errors the system has a high efficiency with a low probability of undetected error. Optimum thresholds are determined for use in dual-rate transmission over fading channels in conjunction with error-detection coding. The remaining studies deal with adaptable receivers. One investigation demonstrates the utility of a rake-type system for orbital dipole channels. The rake system studied is a generalization of the conventional rake system and has the advantage of allowing analog as well as digital modulation. (Author)

Descriptors :   (*FEEDBACK), (*RADIO COMMUNICATION SYSTEMS), (*RADIO RECEPTION), *SATELLITES(ARTIFICIAL)), (*SPACECRAFT), ATTENUATION, CODING, COMMUNICATION SYSTEMS, COMPUTER LOGIC, DATA TRANSMISSION SYSTEMS, DIPOLE ANTENNAS, ERRORS, MATHEMATICAL ANALYSIS, MODULATION, PROBABILITY, RADIO TRANSMISSION, SEQUENCES(MATHEMATICS), SIGNAL-TO-NOISE RATIO, THEORY, WAVE PROPAGATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE