Simple Codes for Fading Circuits

Four relatively simple, redundantly-coded, binary communication systems are considered under certain limiting conditions of signal fading. White noise is assumed to be the only source of errors. A nonredundant, synchronous teletype system is used as a standard of comparison, and all systems are constrained to operate at the same average output data rate. The results indicate that the redundant systems offer significant gains under most of the assumed conditions, but that additional propagation research is required before general codes can be developed for turbulent channels.