Error-floor mitigated and repetitive turbo coding communication system

Abstract

The turbo coding system combines: a) repetitive turbo encoder bit partitioning and decoder bit deletion; with b) error-floor mitigating encoder non-flushing the second constituent encoder with the second a-posteriori probability (APP) decoder starting backward recursion from any possible states as a powerful improvement to conventional turbo coding. The repetitive turbo encoding process repeats the bits of the systematic root sequence and appends flushing sequence prior to interleaving and encoding by the second constituent turbo encoder for providing an interleaved repetitive second encoded output for turbo decoding. The error-floor mitigating turbo encoding process does not flush the second constituent encoder to the zero ending state so that turbo decoding forward recursion may be end in any possible state and backward recursion may start from any possible state to avoid potential mismatches between the forward and backward recursions. The modified a posterior probability second decoder initializes the beginning state metric of the backward recursion with the ending state metric of the forward recursion. The two processes provide significant bit error rate improvement. Iterative decoding provides iterative results that are subject to majority voting selection for improved estimations of the decoded systematic data sequence.