星载合成孔径雷达海浪图像谱仿真研究

Satellite-based SAR image spectrum simulation with Wen's wave spectrum

利用Hasselm ann 的完全非线性积分方法对文氏海浪谱的星载合成孔径雷达(SAR)图像谱进行了仿真研究。结果表明: (1) 在星载SAR海浪成像过程中, 速度聚束调制远比水动力调制、倾斜调制和距离向聚束调制重要;(2) 图像谱有180°的方向模糊和方位向的高波数截断,距离向传播海浪的图像谱存在双峰现象; (3) 不同极化方式和雷达视向的选取对图像谱无明显影响, 因而对于海浪的星载SAR遥感而言, 可以采用单一极化和单一视向。对于不同成长状态的风浪而言, 以上结果保持不变。

Simulation of satellite\|based SAR image spectrum has been carried out using the closed nonlinear integral transformation of K.Hasselmann and S.Hasselmann. The input ocean wave spectrum is Wen\'s theoretic ocean wave spectrum which best characterizes the sea states of the China Seas. The results show that velocity bunching modulation is the most important SAR ocean wave imaging mechanism. 180° ambiguity of wave direction and high azimuthal wave number cutoff exist in all the SAR image spectra. The general splitting of the single wave spectral peak into two peaks for range travelling wave appears in the SAR image spectra. In addition, the relative importance of modulation transfer functions (MTFs) is discussed.