快速收敛的正交振幅调制信号半盲均衡算法  

Fast converging semi-blind equalization algorithm for QAM signals

作　　者：房嘉奇[1] 冯大政[1] 李进[1] 

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,西安710071

出　　处：《电波科学学报》2016年第4期688-694,共7页Chinese Journal of Radio Science

基　　金：国家自然科学基金资助课题(61271293)

摘　　要：针对传输正交幅度调制信号的多输入多输出频率选择性衰落无线通信系统中的信号间干扰与信号内部的码间干扰问题,提出了一种改进的软决策算法.该方法精确地利用了正交振幅调制(Quadrature Amplitude Modulation,QAM)信号星座图信息,避免了经典恒模算法、多模算法中存在的误调问题,提高了均衡性能.对代价函数采用梯度牛顿法进行优化,与常用的梯度类算法相比,其具有更快的收敛速度.通过均方误差和最大信道扭曲分析和验证了该算法的可靠性和有效性.This paper focuses on the problem of intercrossing interference of signals and intersymbol interference for dispersive multiple-input multiple-output （MIMO） systems employing quadrature ampli- tude modulation （QAM） signals. An improved soft decision-directed （ISDD） algorithm is proposed. The proposed algorithm accurately utilizes constellation information of QAM signals and avoids the misadjust- ment presented in classical constant modulus algorithm and multimodulus algorithm, which results in an improvement of the equalization performance. Furthermore, the cost function is optimized by gradient- Newton method. The proposed algorithm converges much faster than the gradient-type algorithms, which are usually used at present. Mean square error and maximum channel distortion are used to analyze the re- liability and validity of the proposed algorithm, respectively.

关 键 词：无线通信 码间干扰 软决策算法 梯度牛顿算法 

分 类 号：TN97[电子电信—信号与信息处理]