时频分析在雷达信号识别中的应用

针对目前雷达信号分选识别的问题，研究了时频分析的方法在信号识别方面的应用。该方法与其他雷达信号识别方法相比，能有效地分析非平稳信号。在时频分析相关理论的基础上，分别研究了基于短时傅里叶(STFT)变换和Wigner-Ville分布(WVD)方法对信号特征的分析和提取。通过仿真，分析对比了两种方法的优劣性, STFT可分析出信号的局部频域特性，而相同信噪比下, WVD比STFT受噪声影响小、聚合度高，能更好地体现时间和频率之间的关系，由此表明，两种方法均可较好地区分出调制信号特征。

Time frequency Analysis in Radar Signal Recognition

The application of frequency analysis in signal recognition for sorting radar signal is discussed. This method offers better efficiency in the analysis of non stationary signals than other radar signal recognition method. Signal feature extraction by the short time Fourier analysis (STFT) transformation and the Wigner Ville Distribution (WVD) is studied respectively and compared by simulation, which shows that STFT can analyze partial frequency domain characteristics of the signal, while at the same SNR, WVD enjoys a smaller noise ratio and a higher degree of polymerization, hence better reflecting the relationship between time and frequency; both methods are able to distinguish the characteristics of modulated signals.