Two-layer dielectric rod antenna for far distance

A dielectric rod antenna (DRA) is designed in such a manner to show good operation all over the X band. For this purpose the rod consists of two concentric dielectric cylinders to achieve the frequency-insensitive behaviour. Generally, two-layer rod antenna has low gain and is not suitable for far distance operation. In this paper, for increasing its gain, two parasitic DRA are employed. The active DRA is composed of a launcher section, followed by a waveguide section and ends in a radiation section. The launcher section, here, is much simpler in comparison to the previous models. At first, a one layer tapered cylindrical-dielectric-rod is fed by a metallic circular cross section waveguide to increase excitation efficiency of hybrid mode and launch this wave into waveguide section. The current design is one of the most ideal antennas that can be used in pulse communication systems.