抛物方程中处理不规则地形的混合算法

The Hybrid Algorithm of Irregular Terrain in Parabolic Equation

首先应用抛物方程并结合分段线性平移变换法预测了不同倾斜角的三角形地形条件下的电波传播特性,其计算结果表明平移变换法在倾斜度较大时产生较大误差。对此提出了分段线性平移变换法与地形屏蔽法相结合的方法,基于此混合方法预测了复杂地形下的电波传播特性;并利用射线跟踪法验证了此方法的可行性。该地形混合方法综合了分段线性平移变换法和地形屏蔽法的优势,在保证计算精度的同时拓宽了复杂地形建模的适用范围。

The parabolic equation combined with the piecewise linear shift map method is applied to predict propagation characteristic over triangle terrain with different slope.The results show that the shift map method can produce large error when dealing with the terrain with large slope.Therefore,the paper presents the hybrid of shift map method and terrain mask method.The forecast of propagation over complex terrain is presented by the hybrid method and the viability is verified by the ray-tracing method.The hybrid method which considers the advantages of shift map and terrain mask improves the accuracy greatly and broaden the range of application of terrain modeling.