Power-efficient Irregular Repeat-Accumulate Encoded BICM-ID for 16-ary Signal Constellations

The design of power-efficient forward error correction techniques over additive white Gaussian noise (AWGN) and frequency non-selective fading channels is considered in this work. The aim of this paper is to investigate the application of BICM with iterative demodulation and decoding (BICM-ID) system with irregular repeat-accumulate (IRA) codes to minimize the bit error rate (BER) and determine the most suitable constellation and mapping pairs for designing powerefficient BICM-ID systems over AWGN and Rayleigh fading channels using the concept of channel capacity limit. Simulation results have confirmed that a remarkable BER improvement can be achieved using the proposed design criterion. Based on the IRA-encoded BICM-ID technique considered, the BER improvement gained is exhibited either as an additional coding gain, error floor elimination, or both. The code components include the IRA codes, irregular low-density parity-check (ILDPC) codes and convolutional codes (CC). The modulation technique considered is the widely-used 16-ary constellations with various bit mappings.