On CRC-Aided, Dual-Trellis, List Decoding for High-Rate Convolutional Codes with Short Blocklengths
Recently, rate-1/n zero-terminated and tail-biting convolutional codes (ZTCCs and TBCCs) with cyclic-redundancy-check (CRC)-aided list decoding have been shown to closely approach the random-coding union (RCU) bound for short blocklengths. This paper designs CRCs for rate-(n-1)/n CCs with short blocklengths, considering both the ZT and TB cases. The CRC design seeks to optimize the frame error rate (FER) performance of the code resulting from the concatenation of the CRC and the CC. Utilization of the dual trellis proposed by Yamada et al. lowers the complexity of CRC-aided serial list Viterbi decoding (SLVD) of ZTCCs and TBCCs. CRC-aided SLVD of the TBCCs closely approaches the RCU bound at a blocklength of 128. This paper also explores the complexity-performance trade-off for three decoders: a multi-trellis approach, a single-trellis approach, and a modified single trellis approach with pre-processing using the Wrap Around Viterbi Algorithm (WAVA).
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