地表后向散射测量实验及其等效介电常数和粗糙度参数的反演

The effective permittivity and roughness parameters inversion by the land backscattering measured data

由于地物类型繁多且分布不均匀,地表粗糙度的测量存在不准确性,且地表分层、体散射机理较难准确界定.针对上述问题,将裸土和水泥路面在入射角小于66°的散射模型等效为面散射模型,联合中国电波传播研究所X波段裸土和Ku波段水泥路面的后向散射实测数据,采用遗传算法同时反演了地表的等效介电常数和等效粗糙度参数,并采用剩余实测数据对反演结果进行了验证,吻合良好.该等效面散射模型在保证裸土和水泥路面后向散射预测精度的同时,降低了模型复杂度,仅需反演面散射模型的3个等效参数(等效均方根高度、等效相关长度和等效介电常数)即可实现对复杂地表后向散射特性的快速、准确预测,具有重要的工程应用价值.

Due to the variety of land features and uneven distribution,the surface roughness measurement is inaccurate and the land scattering mechanism of the layers and volume scattering effects are difficult to distinguish.To solve these problems,the equivalent surface roughness and the equivalent permittivity of the soil and concrete are retrieved simultaneously,by the equivalent surface scattering model,the Genetic algorithms and the measured data from the China Research Institute of Radio Wave Propagation.The land backscattering coefficients predicted by the retrieved parameters are in good agreement with the measured data left.This equivalent surface method simplifies the complexity of the land scattering and it ensures the prediction accuracy of the soil and concrete backscattering coefficient,which only need three equivalent parameters to predict the land backscattering properties fast and accurately.