Hybrid constellation mapping for punctured-node LDPC

Punctured-node LDPC can provide close-to-Shannon-limit waterfall performance and low error floor when carefully designed. In this paper, hybrid constellation mapping is proposed to improve performance of coding and modulation with punctured-node LDPC. General bit interleaving is performed over original puncture-node LDPC to obtain hybrid constellation mapping. By applying non-uniform constellation design methodology, the specific constellation is designed, under which the average mutual information (AMI) is approaching the capacity. Compared with punctured-node LDPC with BPSK modulation, hybrid constellation mapping can provide more than 0.2 dB gain in i.i.d Rayleigh channel according to simulation. Moreover, fewer number of iterations is needed in decoding algorithm of hybrid constellation mapping for punctured-node LDPC, which can reduce decoding complexity and power consumption at high SNR.