高阶MIMO检测中的低复杂度软判决算法研究

新一代无线通信系统均采用了多流空分复用、高阶调制、高码率信道编码等技术以提高吞吐量。针对使用高阶调制的高阶MIMO（Multiple Input Multiple Output）系统，研究低复杂度的检测算法和软输出算法是降低接收机整体复杂度的关键一环。本文选定了复杂度低、易于硬件实现的K-Best为MIMO检测的搜索方法，在探讨了几种近似的次优计算算法基础上，提出了一种复杂度低、性能较好的K-Best软信息简化算法——限幅替代法。仿真结果表明，该方法无论是性能还是复杂度都全面占优。因此，适合用于新一代无线通信系统的MIMO软输出检测。

Research on Low Complexity Soft-out MIMO Detection Algorithms in Multi-layer Systems

MIMO-OFDM technology with multiple layers spatial multiplexing and high-order QAM was being adopted in new generation wireless communication systems as an important approach to increase spectral efficiency. Research on low complexity soft-out detection algorithms is key to reducing the complexity of MIMO receiver. This paper choose the low-complexity, easy-to-implement K-Best as search method for MIMO detection. After discussing several approximation algorithms, a good approximation algorithm for K-Best soft-out detection, Amplitude-limit Replacement, is proposed. Simulation results show that the algorithm has low complexity and good performance. Therefore, it is suitable for soft-out MIMO detection in new generation wireless communication systems.