A hybrid symbol mapping for non-binary LDPC coded modulation with QAM signaling
Xiaoqing Pan, Ming Jiang · 2016
In this paper, we propose a hybrid symbol mapping scheme, which can be extended to any coded modulation systems with non-binary LDPC coding and high-order modulation. For a given configuration of GF(2p) LDPC code and 2q-QAM signaling, we introduce a bit interleaving pattern for a short block across several coded or modulated symbols, where the interleaved bit indices are allocated according to the upper bounds of bit error probabilities with a specific 2q-QAM constellation. In our hybrid mapping scheme, the non-binary coded modulation systems with different interleaving patterns can be efficiently optimized by the numerical thresholds of PEXIT analysis. Both the numerical analysis and simulations verify that the proposed hybrid mapping with optimized interleaving pattern exhibits better performance than the conventional designs.