Propagation and Radiation Characteristics of Dielectric-Wall Conical Horn Antenna

Abstract

Propagation behaviour, aperture field distribution, radiation pattern and gain of dielectric wall conical horn antenna have been studied theoretically and/or experimentally. The solution of Maxwell's equations is obtained for the hybrid (HE/EH) modes using separation of variables technique. The characteristic equation, which has been obtained by applying continuity of electric and magnetic fields at the dielectric-air boundaries, has been solved for the propagation constant for different hybrid modes. The dependence of the root of the characteristic equation related to radial propagation constant for different hybrid modes, on cone length, flare angle and dielectric constant of the horn dielectric, εr2 is also studied. The estimated aperture field distributions obtained for HE11 mode of the horns of different dimensions but each with the same value of the dielectric constant of the horn dielectric, εr2 = 2.56 in φ = 0° and φ = 90° planes are compared with corresponding experimental ones at 9.4 GHz in X-band. The radiation characteristics of these horns are also measured.