Executive Summary : | Till now, very limited research is reported for circular-polarized dielectric resonator antennas (DRAs) excited with waveguide feed in spite of its reduced radiation loss and low interference. The main aim of this proposal is to analyze and design several efficient circularly-polarized DRA configurations excited through the waveguide. The first configuration involves a multilayer DRA configuration slot-coupled to the waveguide shorted end that is also analyzed using the Green's function technique. Both right-hand and left-hand circular polarizations are achieved by suitable optimization of the DRA layer permittivities and the layer radii. For the second configuration, circular polarization is achieved using a waveguide-coupled single-layer radiating DRA with a focusing dielectric resonator (DR) interior to the waveguide. The structure achieves adequate tuning of the axial ratio band by variation in the permittivity of the focusing DR. The third configuration consists of a single-layer circularly polarized DRA fed by a waveguide through a waveguide transition. |