Delayed Bit-Interleaved Polar Coded Modulation with Superposition Gray Labeling

Abstract

We present a delayed bit-interleaved polar coded modulation (D-BIPCM) scheme. Particularly, we consider uniform quadrature amplitude modulation (QAM) and without iterative detection and decoding. We propose a superposition constellation labeling, which treats an M-QAM constellation as the superposition of two Gray-labeled QAM constellations of smaller sizes. The delay indices for D-BIPCM are then designed based on the proposed labeling. The labeling and delay indices joint design accelerates the polarization under a fixed codeword length and consequently improves the error performance of D-BIPCM. Both performance analysis and simulation results show that the proposed design outperforms Gray labeling QAM-based BIPCM and D-BIPCM with the delay indices optimized from the capacity’s perspective.