多径信道下MIMO系统发送天线数估计  

Detecting the Number of Transmit Antennas in MIMO System with Multi-Path Channel

作　　者：李浩[1] 彭华[1] 

机构地区：[1]解放军信息工程大学信息系统工程学院,河南郑州450001

出　　处：《电子学报》2016年第7期1539-1547,共9页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61401511)

摘　　要：为了解决认知无线电或信号截获中多径信道下MIMO系统发送天线数估计问题,首先分析了现有模型在多径信道下失效的原因,将MIMO多径信道模型等效变换出一种虚拟信道矩阵,从而建立多径信道下MIMO系统发送天线数估计模型;然后,利用随机矩阵理论中协方差矩阵最小特征值分布的相关研究结果,证明了时不变瑞利信道的协方差矩阵最小特征值收敛于第二类Tracy-Widom分布,分析了该特点对发送天线数估计的影响,并提出一种改进的RMT估计算法来估计多径信道下MIMO系统发送天线数.最后对改进算法进行了仿真验证,结果表明在低信噪比和小数据条件下,改进算法的估计性能相比RMT算法有较大提升.Under the condition of unauthorized receivers and cognitive radios,the problem of detecting the number of transmit antennas in MIMO system with multi-path channel is to be solved.To achieve this goal,we analyze the invalidation of presenting model and transform the MIMO multi-path channel model into virtual channel matrix to create the model of detec-ting the number of transmit antennas in MIMO system with multi-path channel.Then,the result of least eigen-value of covari-ance in random matrix theory is applied to the proof,which shows that the least eigen-value of channel covariance whose ele-ment obeys the Rayleigh distribution,converges in distribution to the Tracy-Widom law TW2. The effect on detecting the num-ber of transmit antennas of this property is analyzed and an improved algorithm based on RMT,which could detect the number of transmit antennas in MIMO system with multi-path channel,is proposed.At last,the simulation shows that compared with the RMT algorithm the improved algorithm has better performance,in the condition of low SNR and small data size.

关 键 词：多输入多输出 发送天线数估计 多径信道 随机矩阵理论 

分 类 号：TN911.7[电子电信—通信与信息系统]