Hybrid ARQ technique employing a signal constellation rearrangement based on 256-QAM
Bin Pang, Xianhua Dai, Han Zhang, Chang-juan Chen, Jian-qiang Liao, Zhou Xiao · 2008
In this paper, we introduce a Hybrid ARQ (HARQ) technique based on 256-QAM. By employing signal constellation rearrangement, the diversity of bit reliabilities caused by M-QAM signal constellation can be reduced and, thus the corresponding performance of HARQ could be enhanced. We present the standard signal constellation (Gray Mapping) of 256-QAM, in which 3 signal constellations are rearranged to derived 4 types of constellation mapping rules of 256-QAM. Simulation results confirm that the proposed techniqueperforms a noticeable gain in HARQ performance wit a lower complexity.