MMSE准则下近似最优MIMO分组并行检测算法

在采用多天线高阶QAM的MIMO通信系统中,现有基于信道分组并行检测算法虽然接近最优检测性能但以牺牲计算效率为代价.针对这一问题,本文提出一种MMSE准则下基于信道分组的并行检测算法,不但有效降低计算复杂度,而且仍保证检测性能.该算法采用MMSE准则下格归约算法改进分组后条件较好子信道矩阵特性,并在消除参考信号基础上利用改进的子信道矩阵对剩余信号以非线性方式进行检测.仿真结果表明:对4×4和6×6MIMO系统,该算法检测性能达到最优,对于8×8 MIMO系统,比最优算法所需信噪比提高约1dB.复杂度分析表明:相比现有信道分组检测算法,相同检测性能下该算法在6×6 MIMO系统中复杂度降低90%以上,在8×8 MIMO系统中复杂度降低98%以上.

A Near-Optimal Parallel Detection Algorithm Based on Channel Partition and MMSE Criterion

For the MIMO systems with a large number of antennas and a large QAM constellation,the existing parallel detection algorithms,which are based on channel partition,can approach the optimal detection performance but the computational efficiency is sacrificed.In order to solve the problem,a new parallel detection algorithm based on channel partition is proposed.This algorithm can not only efficiently reduce the computational complexity but also guarantee the detection performance.After channel partition,this algorithm firstly employs the lattice reduction algorithm under the MMSE criterion to improve the properties of the sub-channels;and then the remaining signals are detected with a nonlinear method.The simulation results show that the proposed algorithm achieves the near-optimal detection performance for the 4*4 and 6*6 MIMO systems and its performance decreases 1dB for the 8*8 MIMO systems compared to the optimal performance.Complexity analysis shows that its complexity is reduced 90% or above for 6*6 MIMO systems and 98% or above for 8*8 MIMO systems at the same BER.