水面船只SAR探测的极化方式研究

利用SIR-C SAR的C和L波段全极化数据,分析水面船只的极化散射特性和船只与背景海面雷达后向散射的信噪比特性,研究水面船只SAR探测的最优极化方式。结果显示,二面角散射是水面船只SAR成像的主要机理。线性极化中,HV极化具有最大的船只与背景海面雷达后向散射信噪比。与线性极化相比,圆极化的雷达后向散射信噪比更优。C波段和L波段的水面船只的极化散射特性存在较大的差异,L波段的信噪比大于C波段的信噪比。水面船只的雷达后向散射特性表明,L波段的圆极化是水面船只探测的最优极化方式。

Polarization for Sea Surface Ship Detection with SAR

The optimal polarization for sea surface ship detection with synthetic aperture radar(SAR) has been studied using SIR-C SAR C-band and L-band full-polarization data.The radar backscattering properties of the sea surface ship and the ratio of the ship's normalized radar cross section to the ocean's normalized radar cross section have been analyzed.It is shown that the main imaging mechanism of the sea surface ship is the two-corner backscattering.The HV polarization has the largest signal to noise ratio of the normalized radar cross section among the linear polarizations.However,the circular polarization is better than the linear polarization for sea surface ship detection.The C-band radar backscattering properties are different from L-band radar backscattering properties.The signal to noise ratio of the normalized radar cross section at L band is larger than the signal to noise ratio of the normalized radar cross section at C band. The results indicate that the optimal polarization for sea surface ship detection with SAR is the circular polarization at L band.