基于复数格基缩减的V-BLAST系统检测算法及性能分析

Detection algorithm and performance analysis of V-BLAST system based on complex lattice basis reduction

为了提高系统性能,从实数格基缩减出发,推广得到了一种通用的复数格基缩减算法,给出了其在V-BLAST系统中的应用。通过与MMSE扩展相结合,分析缩减与扩展的先后顺序,提出了MMSE-Ⅰ和MMSE-Ⅱ两类基于复数格基缩减算法的V-BLAST检测方案。分析和仿真结果表明,检测中采用复数格基缩减算法与实数算法相比,可以大幅降低复杂度而不影响系统性能;基于复数格基缩减的MMSE-Ⅱ逐层干扰抵消检测算法,可以解决格基缩减引起的有效发送符号之间的相关性问题,且性能接近于ML检测。为了进一步降低复杂度,给出了一种性能损失较小的次优排序方案。

To Dramatically improve the performance of MIMO system,a universal complex Lattice basis reduction（LBR） algorithm was proposed based on real lattice basis reduction（LBR） and its application to V-BLAST system was also provided.Combining with MMSE extension,two types of V-BLAST detection algorithm based on complex LBR,namely,MMSE-Ⅰ and MMSE-Ⅱ,were proposed by analyzing the order of the reduction and the extension.Analysis and simulation results show that compared with real LBR algorithm,the complex one can greatly reduce the complexity while keep the same performance,and that MMSE-Ⅱ successive interference cancellation（SIC） detection algorithm based on complex LBR can deal with the dependency of effective transmitting symbols caused by LBR and achieve near-ML detection performance.To further lower the complexity,a sub-optimum ordering scheme with little performance degradation was provided.