H-plane sectoral dielectric horn antenna

The purpose of this paper is to investigate theoretically and experimentally the radiation aspect of a H-plane sectoral dielectric horn antenna. In the theoretical analysis, the radiated field at a distant point from this antenna is evaluated by determining separately the field from the waveguide in absence of the scatterers (scatterers are flares of the horn) and the scattered field and then adding the two fields at the point. In order to simplify the problem, the volume polarization currents are approximated with sheet currents for thin dielectric flares. The experimental study is carried out at X-band with 10°, 20°, and 30° dielectric (¿r = 2.62) horns and also with 25° dielectric (¿r = 3.0) horn at 1¿ and 2¿ axial lengths in all cases. The results of the experimental investigation show fairly good agreement with the predicted pattern. Limitations of the theory are also discussed.