基于压缩感知的分数阶Fourier域LFM信号检测  

Detection of LFM Signal in Fractional Fourier Domain Based on Compressed Sensing

作　　者：闫浩[1] 董春曦[1] 赵国庆[1] 

机构地区：[1]西安电子科技大学电子信息攻防对抗与仿真技术教育部重点实验室,西安710071

出　　处：《微波学报》2016年第2期84-89,共6页Journal of Microwaves

基　　金：中央高校基本科研业务费专项资金(K5051202026;JB140203);"125"国防预研项目(41101020301)

摘　　要：提出一种新的基于压缩感知CS(Compressed Sensing)理论的LFM信号检测算法。利用LFM信号在分数阶Fourier变换(Fractional Fourier Transform,Fr FT)域稀疏的特点,构造Fr FT矩阵作为LFM信号的稀疏变换基,通过少量待检测LFM信号的随机投影,求解信号在Fr FT域的系数向量,然后对该系数向量进行检测判决,进而达到对感兴趣信号检测的目的。理论分析和仿真实验表明,随机投影点数低至奈奎斯特采样点数的1/10、信噪比低至-8 d B时,该算法对感兴趣的LFM信号检测的成功率可达到95%以上,并且对强窄带干扰不敏感;与波形一致算法相比,该算法在相同信噪比条件下,可以获得更高的信号检测概率。A novel algorithm based on compressed sensing is proposed for LFM signal detection. Because LFM signal has the property of sparsity in fractional Fourier transform domain,construct the Fr FT matrix as the sparse transform base,with a small amount of random projection of the signal,solve the coefficient vector of the signal in the Fr FT domain,then perform threshold detection on the obtained coefficient vector,and thus achieve the purpose of detecting the signal of interest. Theoretical analysis and experiment results show that when the points of random projection are far less than that of Nyquist sampling,the proposed algorithm can accurately detect the LFM signal of interest. Compared with the waveform-matched algorithm,the proposed algorithm can obtain higher probability of detection under the same SNR.

关 键 词：压缩感知 分数阶傅里叶变换 线性调频信号 信号检测 

分 类 号：TN911.23[电子电信—通信与信息系统]