基于最小均方误差的单载波系统低复杂度频域迭代均衡

Low complexity frequency domain iterative equalization based on minimum mean square error for single carrier systems

针对单载波频域均衡(SC-FDE)系统中迭代块判决反馈均衡(IBDFE)算法随迭代次数增加运算复杂度迅速提高的问题,提出了一种低复杂度频域迭代均衡算法。利用均方误差(MSE)准则对检测点误差信号进行分析,对确定的信道增益每次迭代的滤波器系数为定值,并通过在帧结构插入特殊字序列UW作为循环前缀来减小系统开销。理论分析和仿真实验结果表明:本文算法在较高信噪比下比传统的线性均衡性能更好,而在相同迭代次数时接近IBDFE算法性能且比IBDFE算法复杂度大大降低。

In Single Carrier Frequency Domain Equalization（SC-FDE）system,a novel equalization algorithm based on Mean Square Error（MSE）criterion was proposed in order to predigest the complexity of Iterative Block Decision Feedback Equalization（IBDFE）.The coefficients of the filter can be kept unchanged in each iteration based on the given channel frequency response.The Unique Word（UW）sequence,which was inserted into frame structure and the cyclic prefix,could reduce the overhead of the system.The simulation results show that the performance of the proposed algorithm is better than the conventional linear equalization algorithm in high Signal to Noise Ratio（SNR）and close to the IBDFE algorithm in the same iteration times.However,the complexity of the proposed algorithm is lower than that of the conventional IBDFE algorithm.