LF Groundwave Propagation Modeling Over Irregular Terrain by the Hybrid Two-Way Parabolic Equation Method

Abstract

The traditional two-way (2W) parabolic equation (PE) (2W-PE) method has been applied for modeling groundwave propagation over irregular terrain. However, based on a staircase terrain model (STM), the method is not sufficient in sloping facets modeling. Although more accurate one-way PE method based on conformal mapping model (CMM) is available, it handles only forward-propagating waves and neglects the backward-propagating waves, which become significant especially for steep terrain. In this paper, a hybrid 2W-PE method is presented to model the low-frequency (LF) groundwave propagation over irregular terrain. The method combines the STM and CMM to improve the prediction accuracy of both forward and backward propagations. The numerical results are compared with those of the conventional 2W-PE and finite-difference time-domain (FDTD) methods. While calibrated against the FDTD method, the proposed hybrid 2W-PE method has higher accuracy than the traditional 2W-PE method at the same computational cost.