基于多窗傅里叶变换的弱Chirp信号检测  

Weak Chirp Signal Detection Based on Multi-window Fourier Transform

作　　者：吴涛[1,2] 袁嗣杰[2] 梅高杰[1] 

机构地区：[1]装备指挥技术学院研究生管理大队,北京101416 [2]装备指挥技术学院光电装备系,北京101416

出　　处：《装备指挥技术学院学报》2008年第3期96-100,共5页Journal of the Academy of Equipment Command & Technology

摘　　要：关于噪声背景下的Chirp信号检测,已有很多方法：短时傅里叶变换（STFT）、魏格纳-维乐分布（WVD）、Gabor变换等。但在低信噪比条件下,这些方法的检测性能往往难以达到预期的目的。介绍了一种新的时-频分析方法,它联合运用了多种窗长的傅里叶变换分析和局部最大值搜索的方法,运算量小且能有效提高对Chirp信号的检测性能。仿真结果表明,在加性高斯白噪声背景下,该方法对弱Chirp信号的检测能力要优于STFT、WVD和Gabor变换,当信噪比为-9 dB时,依然能检测到信号并确定信号的位置及频率范围。Several methods have been proposed to detect Chirp signal buried in white noise, including STFT,WVD and Gabor transformation, etc. However, when the SNR is very low, these methods would perform poorly and it is hard to obtain the expected purpose. The thesis proposes a new way of time-frequency analysis, which combine the multi-window Fourier transform and Local maximum index. This method requires less computation and performs better than STFT,WVD and Gabor transformation. The simulation results show that, this new way could detect the location and the frequency range of the Chirp signal with the SNR equal to -9 dB.

关 键 词：Chirp信号检测 时频分析 多窗傅里叶变换 局部最大值搜索 

分 类 号：TN911[电子电信—通信与信息系统]