组合半盲均衡算法及其在半盲均衡中的应用  

Study of the Fast Semi-Blind Equalization Algorithm for the QAM Communication System

作　　者：薛海伟[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防科技重点实验室,陕西西安710071

出　　处：《电子科技》2015年第4期4-8,共5页Electronic Science and Technology

基　　金：国家自然科学基金资助项目(61271293)

摘　　要：针对传输正交幅度调制信号的多输入多输出卷积通信系统中的码间干扰和共信道干扰问题,利用软决策算法的选择性以及QAM信号星座图的几何特征,提出一种组合的半盲均衡算法。该算法不仅克服了传统恒模算法,多模算法在稳态下的误调问题,而且避免了SDD算法在高阶QAM系统中运算量急剧增加的问题。采用梯度牛顿法优化CSBEA算法代价函数,与常用的梯度类算法相比,其具有收敛速度快,稳态性能好的特点。通过仿真实验证明了所提算法的有效性。Due to the inter-symbol interference（ ISI） and co-channel interference（ CCI） of the MIMO convolutional communication system driven by QAM signals,a combined semi-blind equalization algorithm（ CSBEA） is proposed by utilizing the selectivity of the soft decision directed（ SDD） algorithm and the geometric properties of constellation of QAM signals. This algorithm overcomes the maladjustment in the steady state of constant modulus algorithm and multimodulus algorithm and avoids the problems of a rapidly increased computational load of SDD algorithm of high order QAM systems. Furthermore,the gradient Newton method is adopted to optimize the cost function of the proposed CSBEA,which brings about a faster convergence speed and a better steady state performance than that of gradient-type algorithms. Finally,several experiments are provided to illustrate the effectiveness of the proposed method.

关 键 词：软决策算法 梯度牛顿算法 收敛速度 稳态性能 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]