Radio wave propagation loss over terrain based on wide angle parabolic equation

We present a method to predict radio wave propagation loss over terrain in the troposphere. Based on wide angle parabolic equation (WAPE), the method is available to the situation that the propagation angle becomes large for the slope of the terrain. We use the Fourier/split step algorithm to solve the WAPE, a terrain shift map to flat the irregular terrain, and the difference approach and the tilting wave front method to predict propagation loss in discrete terrain condition. Comparisons are made with the existing methods including piecewise linear shift map method and the boundary shift method, which indicate that the new method is effective and simple.