Heterodyne n-ary PPM employing Reed-Solomon codes

摘要

A performance and optimization analysis for a Reed-Solomon-codedn-ary pulse-position-modulation (PPM) scheme operating over afiber channel employing heterodyne detection and assuming a Gaussianreceived pulse shape is presented. Calculated results for transmissionefficiency as a function of fiber bandwidth and as a function of PPMsymbol size are discussed. It is concluded that the Reed-Solomon codedn-ary PPM system offers an improvement in transmissionefficiency of typically 4.1 dB over an uncoded system and 11.8 dB over aheterodyne amplitude-shift-keyed pulse-code-modulated (ASK PCM) system.It is shown that a Reed-Solomon-coded n-ary PPM system canoffer the same transmission efficiency as an uncoded system but at asubstantially reduced bandwidth and clock rate