摘要
线性调频(LFM)信号是现代雷达广泛使用的一种大时宽-带宽积的低截获概率信号,根据线性调频信号的小波变换特性,小波脊线与瞬时频率的对应关系,提出了一种检测线性调频信号的联合小波脊线-Hough变换方法,该方法首先计算信号的小波变换,得到二维时-频能量分布图,采用脊算法提取信号的小波脊线,然后在小波脊线时-频平面上再进行Hough变换,从而检测噪声中的线性调频信号并估计信号参数.仿真结果证明,此方法可有效地对线性调频类信号进行检测,并且有较好的抗噪声性能。
Owing to its high time bandwidth product and low probability of intercept, linear frequency modulated signal is widely used in modern radar. Based on wavelet ridge extracting of linear frequency modulated （LFM） signal, a new method used to detect and estimate the LFM signal is presented. It computes the wavelet transform of the signal firstly to obtain the 2D time-scale image, and then extracts the wavelet ridge of the signal with ridge extracting algorithm, finally performs the Hough transform in the time-frequency plane. The detection of lines in the time-frequency plane then reduces to a 2D searching for the peaks in the Hough transform parameter domain. Computer simulation results indicate tliat the method can detect the LFM waveforms in presence of strong noise effectively.
出处
《量子电子学报》
CAS
CSCD
北大核心
2008年第2期145-150,共6页
Chinese Journal of Quantum Electronics
基金
国家863计划(2003AA731120)
航空科学基金(03F5042)资助项目
