Ground wave propagation of a video pulse source: Part 2

In a previous paper we developed a simple model describing the far-field from a video-pulse source near the ground and for grazing incidence. We report here on a recent field test in which we attempted to verify the model. Our results show quantitative agreement with the model for most of the tested parameter space. We have also extended our model to include all elevation angles, including up to vertical. The computed engagement envelope shows three distinct regions: At grazing angles the field is small and diminishes to near zero at the earth's surface; at low-to moderate angles strong lobing occurs; at high angles the video-pulse field approaches its free-space form. 6 refs., 16 figs.