时域欠采样线性调频信号参数估计方法  

Parameter estimation of undersampled LFM sources

作　　者：田达[1] 黄克骥[1] 陈天麒[1] 

机构地区：[1]电子科技大学电子工程学院,四川成都610054

出　　处：《系统工程与电子技术》2004年第7期867-869,880,共4页Systems Engineering and Electronics

摘　　要：针对Nyquist采样频率过高 ,硬件实现困难的问题 ,提出了一种基于分数阶傅里叶变换的时域欠采样线性调频信号参数估计方法。该方法首先用时域解线调方法估计调频斜率 ,然后在分数阶傅里叶变换域进行滤波 ,实现信号提取。利用PRO ESPRIT方法进行初始频率估计。数值仿真表明 ,本方法能够实现多个线性调频信号的高精度参数估计 。In some applications, sampling with Nyquist frequency may be hard to implement due to hardware limitation. A new method for parameter estimation of undersampled LFM (linear frequency-modulated) sources based on fractional Fourier transform (FRFT) is proposed. The method uses time domain dechirp algorithm for chirp rate estimation. By filtering in the fractional Fourier domain, signals are extracted from the mixture of sources and noise. Initial frequency estimates are obtained by using PRO-ESPRIT algorithm. Numerical simulations show that this method can deal with multi-component signals. Parameter estimation with high accuracy is also available at low SNR.

关 键 词：欠采样 线性调频信号 参数估计 分数阶傅里叶变换 

分 类 号：TN911.23[电子电信—通信与信息系统]