一种低副瓣无混叠的线性调频信号时频分析方法  

A Time-frequency Analysis Method for Linear Frequency Modulation Signal with Low Sidelobe and Nonaliasing Property

作　　者：刘会杰 高新海 郭汝江 LIU Huijie;GAO Xinhai;GUO Rujiang(Innovation Academy for Microsatellites of Chinese Academy of Sciences,Shanghai 201203,China;Shanghai Institute of Microsystem and Information Technology,Shanghai 200050;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院微小卫星创新研究院,上海201203 [2]中国科学院上海微系统与信息技术研究所,上海200050 [3]中国科学院大学,北京100049

出　　处：《电子与信息学报》2019年第11期2614-2622,共9页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(91738201);上海市青年科技英才扬帆计划(17YF1418200)~~

摘　　要：作为通信与勘探中广泛使用的一类信号,线性调频信号的参数分析经常采用基于Wigner-Ville分布(WVD)的时频分析方法。该方法具有高时频分辨率,但在交叉项、高副瓣以及频谱混叠问题上存在缺陷。该文提出一种名为空间变迹重排Wigner-Ville分布(SVA-rWVD)的时频分析方法,结合空间变迹技术(SVA)的副瓣抑制能力及短时傅里叶变换(STFT)的无混叠无交叉项特性,得到一个新的时频分布。基于单分量和多分量线性调频信号的仿真实验结果表明,该方法得到的时频分布可以降低副瓣水平至–40 dB以下同时消除交叉项及频谱混叠现象。Chirp signals are widely used in communication and exploration.The parameter analysis of the chirp signals often uses a Wigner-Ville Distribution(WVD)based time-frequency analysis method,which achieves high time-frequency resolution.However,this method has defects in cross terms,high sidelobes,and spectral aliasing problems.To solve these problems,a time-frequency analysis method called Spatially Variant Apodiztion-rearrange Wigner Ville Distribution(SVA-rWVD)is proposed,which achieves low sidelobes by exploiting the Spatially Variant Apodization(SVA)techniques,and avoids the cross terms and the spectral aliasing problems by applying the Short Time Fourier Transform(STFT).Furthermore,a new time-frequency distribution is obtained from the proposed method.Extensive simulations show that the time-frequency distribution obtained by the proposed method not only reduces the sidelobe level to–40 dB but also eliminates cross terms and spectral aliasing for both single-component and multi-component chirp signals.

关 键 词：时频分析 线性调频信号 WIGNER-VILLE分布 空间变迹 短时傅里叶变换 

分 类 号：TN911[电子电信—通信与信息系统]