摘要
线性调频信号(Linear Frequency Modulated,LFM)是一种非平稳信号,它的参数估计比一般的平稳信号的参数估计要复杂,利用时频分析对其进行处理是有效而直接的手段。本文针对传统的基于分数傅里叶变换(Fractional Fourier Transform,FRFT)对chirp信号进行参数估计需要在整个时频平面进行二维搜索,运算量大,不利于处理这一问题,提出一种快速估计法来对chirp信号进行参数估计。利用快速傅里叶变换(Fast Fourier Transform)快速粗略地估计信号的调频斜率,从而缩小二维谱峰搜索运算的搜索范围,大幅度降低计算复杂度并能提高估计速度与精度。仿真结果表明,该算法对在高斯白噪声中的线性调频信号的参数有良好的估计性能。
The chirp signal is a non-stationary signal, and its parameter estimation is more complex than the general stationary signal. For its processing, the time-frequency analysis is the most direct and effective mean. The traditional paprameter estimation to chirp signal based on fractional Fourier transformation needs two-dimensonal searching throughout the whole plane, the large amount of computation is not a suitable processing. For this reason, this paper puts forward a fast estimate method to estimate the parameter of chirp signal, then reduces the searching range of two-dimension spectrum peak searching operating, it highly reduces the complexity of calculation, increases the speed and precision of estimation. Simulation results show that the algorithm has a good estimation property to the parameter of chirp signal in white Gaussian noise.
出处
《自动化技术与应用》
2015年第8期53-57,共5页
Techniques of Automation and Applications
关键词
线性调频信号
分数傅里叶变换
参数估计
快速估计法
chirp signal
fractional Fourier transform
parameter estimation
pre-judgment method
