MODEL EXPERIMENTS OF MEDIUM-WAVE BROADCASTING ANTENNA ON A MOUNTAIN TOP.

Abstract

The basic characteristics of a medium-wave broadcasting monopole antenna erected on an isolated, axially symmetric lossy mountain above a perfectly conducting plane are investigated experimentally by using a small scale model (1000:1). The experimental mountain model consists of a hemisphere and a truncated cone filled with a lossy gelled medium called Asron. The imput impedance, the radiation efficiency, the gain, and the radiation patterns are measured. Some of these measured results are compared with the theory. The model experiments generally confirm the theory that an antenna erected on a mountain top can improve the radiation efficiency and the gain compared with the case where the antenna is erected on a plane when the length of the antenna and the height of the mountain are moderate and appropriate.