VMA-OFDM系统中多频偏和信道联合MLE算法  

Multiple frequency-offset in VMA-OFDM system and MLE algorithm for channel-joint

作　　者：姜建[1] 姜华[1] 严凯[1] 刘海涛[1] 

机构地区：[1]中国科学院上海微系统与信息技术研究所,上海200050

出　　处：《华中科技大学学报（自然科学版）》2009年第7期6-9,13,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家高技术研究发展计划资助项目(2006AA01Z216)

摘　　要：针对虚拟多天线正交频分复用(VMA-OFDM)系统目的节点中数据辅助的多频偏和信道参数估计问题进行了研究,设计了一种次优最大似然估计(MLE)算法.该算法在矩阵的求逆中采用了级数展开,从而使得算法的复杂度与基于最大似然准则估计算法相比显著减小,在算法的性能和复杂度之间进行折衷,解决了最大似然估计算法过于复杂而难以实现的问题.在算法的性能方面,理论分析和仿真结果表明,基于该算法的频偏和信道参数估计的均方误差逼近Cramer-Rao下界(CRB);在算法的效率方面,该算法允许各个中继节点同时发送训练序列,从而降低传输训练序列所占用的时间.The joint data-aided estimation of multiple frequency offsets and channel coefficients in virtual multi-antennas orthogonal frequency-division multiple（VMA-OFDM） systems were studied, and a suboptimal maximum likelihood estimators（MLE） was introduced. The series was expanded in the matrix inversion. Compared with the existing estimators based ML, the computational cost of the proposed estimators is reduced significantly. The algorithm exhibits an attractive tradeoff between performance and complexity, and properly settles the problem that the MLE is impractical in this context. As far as the performance is concerned, the proposed suboptimal estimators are shown to be asymptotically efficient, i. e. , the frequency offsets and channel coefficients estimation mean square error（MSE） achieves the Cramer-Rao bound（CRB）. Simulation results sustain our claims. As far as estimation efficiency is concerned, the algorithm allows the relay nodes to transmit the training sequence simultaneously, which will greatly reduce the training sequence transmission time.

关 键 词：无线通信系统 虚拟多天线正交频分复用 信号处理 无线传感网 能量有效 最小均方误差 

分 类 号：TN911.23[电子电信—通信与信息系统]