地面实验条件下土壤水分微波辐射特性

Microwave radiation characteristics of soil moisture based on ground experimental conditions

为解决被动微波遥感反演土壤水分问题,通过C、KU两个波段微波辐射计对不同水分的裸露地表的土壤微波辐射特性进行实验研究,分析土壤湿度与土壤的微波发射率之间的定量关系,建立了土壤湿度与微波发射率的经验模型。研究结果表明：在土壤表面平整时,土壤湿度与土壤微波发射率呈线性负相关,即随着土壤湿度的增加,土壤微波发射率线性下降。在入射角为30°～50°范围内,无论是垂直还是水平极化,30°入射角时微波对土壤测湿灵敏度最大,表明在入射角30°的水平极化下微波反演土壤水分的效果最好。

In order to solve the problem ot soil moisture reversion using passive rmcrowave remote sensing, experimental of soil microwave radiation characteristics of different soil moisture using the C and KU-band microwave radiometers were carried out. Then the quantitative analysis between the soil moisture and the soil microwave emissivity were analyzed. Finally, this paper established the empirical models of soil moisture and microwave emissivity. The results show that when the soil surface is smooth, soil moisture and its microwave emissivity is linear negative correlated, i.e. with increasing soil moisture, soil microwave emissivity decreases linearly. In the angle of incidence between 30°and 50°, whether vertical or horizontal polarization, the soil moisture measuring sensitivity of microwave is the largest in 30°angle. It shows that the effect of microwave inversion soil moisture is the best under horizontal polarization in 30°incident angle.