Modelling of shielding effect of a fence on the performance of a Yagi antenna

摘要

This paper concerns the effect of a metal fence on the near and far fields of a Yagi antenna. We use a moment method implementation of the electric field integral equation for our computations. The presence of the fence generally lowers the field intensity in the near shadow region of the fence. However, in the far field, the presence of the fence can, depending on the geometry, in fact raise the field intensity. The fence's influence on the fields depend upon a number of factors including antenna frequency, distance between the antenna and the metal fence, observation angle, and the height and width of the fence and its inclination to the ground. The effect of these parameters on the antenna performance is investigated. Some recommendations are made for the optimum use of metal fences as shields.