MIMO detection for high-order QAM constellations based on successive decision feedback semidefinite relaxation

摘要

A semidefinite relaxation(SDR) scheme for high order quadrature amplitude modulation (QAM) in multiple input and multiple output (MIMO) system is proposed in this letter. By performing bound-constrained semidefinite relaxation (BC-SDR) and its tightened version successively, a very low complexity suboptimum approach for high order QAM signal detection can be obtained. The analysis and simulations demonstrate that the proposed successive decision feedback semidefinite relaxation scheme could outperform BC-SDR and approach its tightened version performance but with much lower complexity.