Efficient soft demapping for M-ary APSK

摘要

In this paper, we present an efficient soft demapping method for M-ary APSK based on hard decision thresholds (HDT). The proposed scheme is of great reducing in computational complexity compared to maximum likelihood detection (MLD) using log likelihood ratio (LLR) and Max LLR. We demonstrate the bit error rate (BER) performance of various soft demapping methods combined with turbo codes. The BER simulation results reveal that the proposed method can achieve almost approximating performance to MLD.