在分析已有散射模型的基础上,依据广义Rayleigh Gans近似,计算了微波在土壤、棉层中散射的一级和二级效应,对影响散射的主要因子(入射波频率、入射角,棉叶冠层厚度、棉叶大小、叶厚、空间分布等)进行了分析。其中最主要的影响因子是入射波频率与棉叶大小的相对比值。研究结果表明:对于已封垄的棉田散射,在小入射角时以土壤的面散射为主。

The research on crops microwave scattering model is developing fast. But, the integrated study of both volume and surface model is still in the beginning stage in China. This paper applies the combined model to the cotton soil media and conducts some exploring works. Microwave scattering in cotton soil media has been calculated from zero, first to second order scattering. The paper analyses major factors which affect the backscattering coefficient. Some valuable conclusions have been drawn. Among these, the incident wave frequency and cotton leaf radius are the major factors. For cotton field scattering in small incident angles (<30°), the major scattering is from soil surface, when the incident angle is more than 30°, the major scattering is from cotton canopy. It may be helpful for cotton microwave remote sensing monitoring and discrimination.