Numerical approach for predicting radiation patterns of HF-VHF antennas over irregular terrain

The feasibility of using a direct numerical integration of physical optics fields for computing radiation patterns of ground-based HF-VHF antennas in the presence of known ground irregularities is examined. The initial study treats a special case of a line source above a perfectly conducting plane with a semicylindrical boss. This case permits a comparison of results computed using physical optics formulations to the exact values. The agreement is gratifyingly close, which justifies an extension of such a study to a three-dimensional case.