Radiation Characteristics of the Cylindrical Monopole Imbedded in the Dielectric Layer

In this paper the computational modelling of cylindrical monopole antennas in the dielectric layers has been carried out and the experimental results on the investigations of the given class of antennas have been analyzed. The dielectric layer availability provides the beamwidth increasing and the elevation angle of peak directivity moving to the azimuth in the radiation pattern in comparison with the usual cylindrical monopole antenna. At the same time the rest of power characteristics remain virtually the same. We have determined that for the ground plane radius R > 7lambda/4 the resonant modes of antenna appear and radiation pattern becomes the multi-beam one. In this case a number of lobes depend on the spatial frequency of surface waves in the dielectric layer. Furthermore, it is accompanied by increasing the radiation intensity of the lobes closer to zenith.