项目名称: GPS-IR监测土壤水分含量的反演模型研究
项目编号: No.41504024
项目类型: 青年科学基金项目
立项/批准年度: 2016
项目学科: 天文学、地球科学
项目作者: 吴继忠
作者单位: 南京工业大学
项目金额: 20万元
中文摘要: 土壤水分含量是全球能量与水循环中的重要参数,以较低的成本自动化获取实时、高时间分辨率的土壤水分含量是气象、水文、生态、农业等学科中的基础性科学问题之一。本项目从信噪比数据的构成方式入手,分析不同信号成分的频率分布特征,研究反射信号的频域提取方法;研究针对非线性模型的干涉参数快速稳健估计策略和算法模型,建立多次散射信号的识别准则,消除多次散射信号对干涉参数估计的影响;研究植被这一主要干扰因素对反射信号的作用机制,阐明植被对反射信号干涉参数影响的物理机理,并在此基础上,引入植被状态参数,建立顾及植被影响的土壤水分含量多元反演模型。本课题的研究,将解决GPS-IR反射信号参数到土壤水分含量转换的的瓶颈问题,为实现GPS参考站网监测土壤水分含量提供理论和技术支持。
中文关键词: GPS-IR;土壤水分含量;干涉参数;反演模型;非线性模型
英文摘要: soil moisture is the key parameter in global energy and water cycle, the retrieval of real-time and high temporal resolution soil moisture with automation and low cost is a basic scientific problem in meteorology, hydrology, ecology and agriculture studies. This study will focus on analyzing the composition of signal-to-ratio and the frequency characteristic of direct and reflected signals, extracting the reflected signals in frequency domain; estimating the interferogram parameters of reflected signals with nonlinear model under complicated surroundings where both single and multiple scattering exist simultaneously, proposing the recognition criterion of multiple scattering in order to eliminate the effect on interferogram parameters estimation; revealing the physical mechnism of vegetation acts on interferogram parameters of reflected signal on the basis of analyzing the dynamic response of reflected signal to vegetation. Besides, introducing the vegetation parameter and constructing the soil moisture polyphyletic retrieval model which considering the vegetation effect. This research work will solve the key issues in soil moisture retrieval with interferogram parameters, consequently provide the theoretical and technical supports for soil moisture retrieval with GPS reference stations.
英文关键词: GPS-Interferometric Reflectometry; soil moisture ;interferogram parameters ;retrieval model ;nonlinear model