分数阶自相关和FrFT的LFM信号参数估计

基于分数阶自相关和分数阶傅里叶变换的特点，提出了一种LFM信号检测与参数估计方法。相对分数阶傅里叶二维扫描法和匹配傅里叶变换，所提方法将检测与参数估计的二维搜索变为一维搜索，快速实现信号检测和参数估计，在多分量LFM信号情况下借助“Clean”的方法来抑制强分量对弱分量的干扰。计算机仿真表明了该算法在低信噪比多分量LFM信号检测与参数估计中的有效性。In this paper, a fast method for parameters estimation of the multi-component linear frequency modulated (multi-LFM) signal is proposed. The proposed algorithm reduces two-dimensional searches, widely used in the time-frequency based method, FrFT and Chirp Fourier transform, into two one-dimensional searches. With utilizing the discrete FrFT along with Fast Fourier Transform (FFT) algorithm, the proposed method is a computationally fast alternative for LFM signal detection and parameters estimation. Analysis of the multi-LFM signal is performed using the Clean technique. Finally, computer simulations are provided to illustrate performances of the proposed algorithm.