【摘要】 本文研究了利用时-频分析方法进行合成孔径雷达运动目标成象的若干问题。分析了三种时-频变换方法——短时傅里叶变换,小波变换和Wigner-Ville分布(WVD),提出只有WVD才能满足要求。针对WVD的双线性特性所造成的交叉项干扰问题,提出用Hough变换来抑制交叉项。实验证明,即使在信噪比很低时,WVD和Hough变换结合的方法仍能提供很好的检测性能。更多还原

【Abstract】 Some problems about SAR moving targets imaging by joint time-frequency analysis are discussed in this paper. Three kinds of time-frequency transforms - Short Time Fourior Transform(STFT), Wavelet Transform(WT) and Wigner-Ville Distribution (WVD) are compared. It is presented that only WVD could meet the requirement. Moreover, Hough Trans-form(HT) is employed in restraining the disturbing cross terms, produced by the WVD due to its bilinear property. Experiments test that the combined WVD and HT could provide satisfactory detection performance even if the signal-to-noise ratio is very low.更多还原