An Efficient Code Structure of Block Coded Modulations with Iterative Viterbi Decoding Algorithm

Block coded modulations (BCM) with iterative Viterbi decoding algorithm can provide both high transmission throughput and small error probability. In this paper, a new code structure is proposed to further improve the performance. The strategy of the new code is to add parity check codes at corresponding coding levels of BCM to increase the Hamming distances among codewords. Decoding trellis of Viterbi decoding to support the new code structure is also developed. It is shown that the proposed code structure can not only guarantee the Euclidean distance of BCM but also mitigate the burden of iterative decoding. As a result, the proposed code structure can provide better transmission rates than the old one with identical or less decoding complexity. Computer simulation shows that the proposed code structure is also beyond the old one in bit error rate performance.