一种低复杂度空间调制球形译码检测算法

现有的空间调制系统球形译码（Sphere-Decoding，SD）检测算法虽然能够较大地降低最大似然（Maximum-Likelihood，ML）检测算法的计算复杂度，但由于其更新半径比较松散、收敛较慢，计算复杂度降低的水平仍十分有限，尤其是在高阶调制系统下.针对上述问题，采用统计分布的思想对现有算法更新半径中的冗余项进行估计，提出了两种改进的球形译码检测算法.理论分析与仿真结果表明，改进算法在达到最优检测性能的同时，极大地降低了传统球形译码的计算复杂度，具有较好的理论和实际应用意义.

A Low-Complexity Sphere-Decoding for Spatial Modulation

Although the existing sphere decoding algorithm of the spatial modulation systems can greatly reduce the computational complexity of the maximum-likelihood (ML) detection,due to its loose updating radii and slow convergence,the level of computational complexity reduction is still very limited,especially in high-order modulation systems.To solve the problem,the statistical distribution is used in this paper to estimate the redundancy in the updating radii of the existing algorithm,and two improved sphere decoding algorithms are proposed.Theoretical analysis and simulation results show that the improved algorithms can greatly reduce the computational complexity of the traditional sphere decoding while achieving the same performance with ML detection,which have great theoretical and practical significance.