V-SMCG算法对起伏月面异常回波的定量研究

Quantitative study of the anomalous scattering echoes of rough lunar surface by V-SMCG algorithm

本文基于月面石块的分布模型和概率分布函数,采用蒙特卡洛反函数法建立随机分布石块的月面几何模型.基于Maxwell积分方程发展了矢量稀疏矩阵规范网格法(Vector Sparse Matrix Canonical Grid, V-SMCG)矩量法的求解过程,数值仿真了不同月面几何的全极化复散射回波,并根据Mini-RF雷达观测配置计算回波圆极化比(Circular Polarization Ratio, CPR).仿真结果表明:月面随机分布石块引起月面几何起伏粗糙度的增加,多次散射明显增强了雷达后向回波,并使得CPR值出现大于1的情况,尤其是大于波长尺度的石块会使得CPR值远远大于1.

Based on the probability distribution function of the stones, the model of the stones is established using the inverse function method of Monte Carlo Method. Then the full polarization radar echo is calculated according to the Maxwell integration equations, using method of moment accelerated with V-SMCG algorithm. Then the circular polarization ratio (CPR) is calculated according to Mini-RF radar observation configuration. The simulation results show that random stones distribution causes surface roughness and backscattering echo enhancement. Moreover, the multiple scattering of stones can cause anomalous CPR in radar echoes, especially for the stones with size larger than wavelength.