Performance of probabilistic amplitude shaping with BICM-ID

Abstract

It is numerically shown that bit error rate (BER) performance of probabilistic amplitude shaping (PAS) applying a bit-to-symbol mapping of non-Gray natural binary code assigned to 64-quadrature amplitude modulation is significantly improved by bit-interleaved coded modulation with iterative detection (BICM-ID). The obtained BER performance outperforms the PAS using a standard Gray code mapping. Furthermore, it has been numerically verified that the non-Gray natural binary code mapping is suitable for BICM-ID by analysing the extrinsic information transfer chart. In addition, two degradation factors, the shaping and the coding gaps are estimated, from the Shannon limit by analysing mutual information characteristics. The obtained results quantitatively show that BICM-ID can effectively suppress the coding gap of the PAS applying non-Gray mapping in BER performance.