基于压缩感知理论的超宽带信道估计  

Channel Estimation Based on Compressed Sensing in UWB Systems

作　　者：王开[1] 刘郁林[1] 张先玉[1] 

机构地区：[1]重庆通信学院,重庆400035

出　　处：《计算机仿真》2011年第6期132-135,共4页Computer Simulation

基　　金：国家自然科学基金(6067215760672158);重庆市自然科学基金(CSTC2009BB2028)

摘　　要：针对超宽带通信系统的信道估计中需要对极窄脉冲采样,要求模数转换器的采样速率极高,但目前的硬件制作水平达到采样速率要求较为困难。为降低超宽带信道估计对采样速率的要求,提出一种基于压缩感知理论的信道估计新方法。利用超宽带信道在时域上的稀疏性,通过准Toeplitz测量矩阵将信道估计模型转化为压缩感知理论中的稀疏向量重构模型,在接受端只需对输出样值进行较低速率的采样,即可准确重构信道抽头系数并进行仿真。仿真结果表明,方法仅需1/5-1/10奈奎斯特采样速率即可准确估计信道,且同等信噪比条件下估计的均方误差较传统信道估计算法下降约6-8dB,可以为设计提供可靠的依据。Extremely high-speed analog-to-digital converters（ADCs） are required to sample the extremely narrow pulses in the estimation of UWB channels.It is difficult to meet the requirement of sampling rate under the current level of the hardware production.In order to reduce the excessively high requirement of the sampling rate in UWB systems,a novel method for channel estimation was brought forward in this paper based on compressed sensing.Considering the time-domain sparsity of UWB channel,CS reconstruction model was transformed from channel estimation model by using the Quasi-Toeplitz matrices.The channel tap can be estimated from relatively few observations collected at the receiver.Simulation results show that the Nyquist sampling rate of 1/5-1/10 will be sufficient to channel estimation in UWB systems.Comparing with traditional method,the estimated MSE of the novel method decreased by 6-8dB under the similar SNR.

关 键 词：压缩感知 超宽带 准托普利兹矩阵 信道估计 稀疏性 

分 类 号：TN911.5[电子电信—通信与信息系统]