覆盖雪层土壤面的电磁波透射特征

Transmission Characteristics of Electromagnetic Wave Through Soil Surface Covered by Snow

采用指数型粗糙面模拟实际的粗糙雪层和土壤表面,运用矩量法(MoM)结合基尔霍夫近似(KA)的混合算法研究了雪层覆盖土壤面的电磁波透射特征。混合算法将雪层表面划分在MoM区,土壤面划分在KA区,数值计算得到了透射系数的角分布曲线,分析了雪层和土壤表面的高度起伏均方根、雪层类型、土壤湿度、雪层厚度对透射系数的影响。结果表明,雪层表面高度起伏均方根、雪层类型、土壤湿度对透射系数有显著影响,而土壤表面高度起伏均方根和雪层厚度对透射系数影响较小。

The rough surface of snow and soil is simulated using a rough surface of exponential type. The transmission characteristics of electromagnetic wave through the soil surface covered by snow is investigated using the hybrid method based on the Method of Moment （MoM） and the Kirchhoff Approximation （KA）. The snow surface and the soil surface are divided into an MoM region and a KA region by the hybrid method. The angular distribution of the transmission coefficient is obtained by the numerical calculation. The influences of the root-mean-square height of the snow surface and the soil surface, the type of the snow layer, the soil moisture, the thickness of the snow layer on the transmission coefficient are analyzed. It is indicated that the root-mean-square height of the snow surface, the type of the snow layer and the soil moisture have a considerable influence on the transmission coefficient,, but the influence of the root-mean-square height of the soil surface and the thickness of the snow layer can be neglected.