用SIR-C航天飞机双频极化干涉雷达估计植被高度的方法研究

基于重复轨道航天飞机SIR—C的L和C波段极化干涉雷达数据，提出了一种将三阶段反演方法(Three—Stage Inversion)和ESPRIT(Estimation of Signal Parameters via Rotational Invariance Techniques)算法相结合的新的相位基植被高度估计方法。首先，基于L波段极化干涉数据，用三阶段反演方法获取植被覆盖地表下地形有效散射中心的相位；接着，基于c波段极化干涉数据，用ESPRIT算法估计植被冠层有效散射中心的相位；最后，对二者的相位差进行相位到高度的转换得到植被的高度。根据研究区域的实测林相数据，对该算法估计的植被高度结果进行了比较和验证，结果表明：该方法具有足够高的植被高度估计精度，如果能得到P和X波段的双频极化干涉雷达数据，该方法估计植被高度的精度将会得到进一步的提高。

Method study of vegetation height estimation using SIR-C dual frequency polarimetric SAR interferometry data

A new hybrid method for estimation of vegetation height, characterized by combining three-stage inversion method and ESPRIT(Estimation of Signal Parameters via Rotational Invariance Techniques) algorithm, is proposed based on SIR-C's dual frequency polarimetric SAR interferometry data. Firstly, topographic phase is located by three stage inversion method using L band Pol-InSAR data. Next, vegetation canopy scattering center phase is resolved by ESPRIT algorithm using C band Pol-InSAR data. Finally, the estimated vegetation height is obtained from the transformation of phase difference to height. The estimated vegetation height are compared with the field measurement data. The result indicates that the new proposed method can estimate the vegetation height with high accuracy, and if the P and X band Pol-InSAR data can be obtained, the accuracy of the inversion method will be significantly increased.