为了研究辐射源的细微特征分析,针对目前主流的几种离散傅里叶变换(DFT)频偏估计算法分析载频频偏精度不够高的问题,提出一种基于细化快速傅里叶变换(Zoo-鄄FFT)的改进DFT算法。该算法先对离散采样的信号采用Candan算法进行粗估计,再将频谱峰值周围的频段进行细化放大,然后利用2N点DFT算法对残余频率精细估计。该算法综合了上述两种算法的优点,能够在适当信噪比环境下达到很好的估计精度。文中以二次雷达信号为研究对象,仿真分析验证了算法的可行性与有效性。

In order to study the analysis of subtle feature of the radiation source, an improved discrete Fourier transform (DFT) al鄄 gorithm based on Zoom-FFT is proposed for the problem that current mainstream carrier frequency offset accuracy of DFT frequency offset estimation algorithms is not high enough. The Candan algorithm is firstly used by the algorithm for rough estimation of the discretely sampled signals. Then the frequency bands around the peaks of the spectrum are refined, and the 2N point DFT algorithm is used to estimate the residual frequency. The algorithm combines the advantages of the above two algorithms and achieves good estimation accuracy in an appropriate signal to noise ratio environment. In this paper, the secondary radar signal is taken as the research object, and the feasibility and effectiveness of the algorithm are verified by simulation analysis.

TN957.51

国家自然科学基金资助项目;安徽省自 然科学基金资助项目