SC-FDE系统中基于压缩感知的慢衰落航空稀疏信道估计  

Estimation of Slow Fading Aeronautical Sparse Channel Based on Compressed Sensing in SC-FDE System

作　　者：毕号旗 向新[1] 李娜[2] 郑万泽 鞠明 BI Haoqi;XIANG Xin;LI Na;ZHENG Wanze;JU Ming(Aeronautical Engineering college,Air Force Engineering University,Xi’an 710038,China;School of Telecommunications Engineering,Xidian University,Xi’an 710071,China;Academic Research Office,Air Force Engineering University,Xi’an 710051,China;Unit of 91313,Beijing 100038,China)

机构地区：[1]空军工程大学航空工程学院,西安710038 [2]西安电子科技大学通信工程学院,西安710071 [3]空军工程大学科研学术处,西安710051 [4]91313部队,北京100038

出　　处：《空军工程大学学报（自然科学版）》2020年第5期82-88,共7页Journal of Air Force Engineering University(Natural Science Edition)

摘　　要：针对慢衰落时变航空多径信道码间串扰严重、接收端误码率高的实际问题,在SC-FDE系统的基础上,分析了航空多径信道的稀疏性,将航空信道估计建模为稀疏信号的恢复问题,采用PN序列构造确定性测量矩阵,以基于稀疏度自适应匹配追踪算法作为恢复算法,建立PN-SAMP信道估计算法;比较了压缩感知类算法和传统的PN算法、LS算法的估计均方误差,并结合MMSE均衡比较了几种估计方法应用在SC-FDE系统中的误码性能。仿真结果表明,压缩感知类算法比传统PN算法和LS算法的估计误差要小,误码率也更低,在信噪比为20 dB的条件下,压缩感知类算法的误码率小于10-4。在稀疏度未知的情况下,PN-SAMP算法比正交匹配追踪算法更稳健,更能满足对时变慢衰落航空稀疏信道的估计需求。Aimed at the problems that the inter symbol interference is severe and the bit error rate is high at the receiving end of slow decaying variable air multipath channels,on the basis of SC-FDE system,the sparsity of airborne multipath channels is analyzed,the airborne channel estimation model is taken as a recovery problem for sparse signals,and a PN-SAMP channel estimation algorithm is proposed based on a compression-aware framework by using PN sequences to construct a deterministic measurement matrix with SAMP as the recovery algorithm.The estimated mean square errors of compression-aware algorithms are compared to that of the traditional PN and LS algorithms,and the error performance of several estimation methods applied in SC-FDE systems is compared in conjunction with MMSE equalization.The simulation results show that the estimation errors and the bit error rates of compression-aware class algorithms are smaller and lower than that of the traditional PN and LS algorithms respectively,and the bit error rate of the compression-aware class algorithms is less than at a signal-to-noise ratio of 20dB.The robust of the PN-SAMP algorithm is better than that of the OMP algorithm in the case of unknown sparsity,further meeting the estimation needs of sparse channels in the time-varying slow-decay aviation.

关 键 词：航空信道 信道估计 压缩感知 单载波频域均衡 

分 类 号：TN911.72[电子电信—通信与信息系统]