多层积雪相干散射模型与SAR参数反演

项目名称： 多层积雪相干散射模型与SAR参数反演

项目编号： No.41471065

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 李震

作者单位： 中国科学院遥感与数字地球研究所

项目金额： 95万元

中文摘要： 针对主动微波信号在植被覆盖区多层积雪传输中的相干散射机制问题，基于密集介质辐射传输理论，考虑雪层的多层特性和雪粒子间的相干散射，从解析求解和数值模拟两方面入手，得到不同积雪参数条件下雪层的消光系数、散射系数和相矩阵，并加入空气－雪层、雪层－地表边界和植被覆盖条件，建立适用于主动微波后向观测的植被覆盖区多层积雪相干散射模型。 通过分析植被覆盖、雪密度、雪厚度等物理参数与后向散射系数的响应关系，建立考虑植被影响的积雪参数反演模型与方法。开展积雪区野外观测实验，获取星载SAR数据、散射特性测量数据和地面同步观测数据，验证发展的积雪模型和积雪反演方法的可靠性。 本项目将解决过去辐射传输方程解析解精度不足问题，植被覆盖条件下积雪参数反演问题，为多源极化SAR数据的应用提供理论和技术支持。

中文关键词： 积雪参数反演；散射模型；冰冻圈；雷达遥感

英文摘要： Focus on the coherent scattering transmission mechanisms problem of active microwave signal in the SAR image of multi-layer snow under vegetation cover, we will establish the multi-layer snow coherent scattering model applies to the active microwave observation under vegetation coverage condition, based on Intensive Media Radiative Transfer equation, considering the multi-layer features of the snow layer and the coherent scattering between snow particles. By means of the analytic solution and numerical simulation two-pronged approach, the model will be calculated the extinction coefficient, scattering coefficient and phase matrix of the snow layer at the different snow parameters conditions, joined boundaries condition of the air-snow layer and the snow-surface layer, and vegetation cover conditions. We will develop the snow parameter retrieval models and methods through the analysis of response relationship of vegetation cover, snow layer physical parameters to the back scattering coefficient, and will validate the model and test algorithms by carrying out collaborative observation experiment, obtaining spaceborne SAR, scattering characteristics measurements and in-suit field samples of ground snow cover and vegetation parameter measurement,to validate scattering model and retrieval algorithms. The project will solve the shortage problem of analytical solution accuracy for the radiative transfer equation in the past, the inversion problem of snow parameters considering the vegetation cover and providing theoretical and technical support for the applications of multi-source polarization SAR.

英文关键词： Snow Parameters Retrival;Scattering Model;Cryosphere;Radar Remote Sensing