Engineering Commons^™

Radiation From A Tapered Dielectric Rod Antenna, Anil Prabhakar

Theses

The radiation fields from a cylindrical dielectric taper is studied. The numerical results of a theoretical model for a taper excited by the dominant HEn mode is compared with experimental measurements. A theoretical mode] for the next propa¬gating mode in the structure. the TE01 mode. is investigated and numerical results based on this proposed model are generated. The theoretical models are based upon the combination of the exact modal field solutions for a step profile cylindrical dielectric rod waveguide. local mode Hum-T. and the equivalence principle for the determination of equivalent current densities.

The far-zone radiation field is considered to …

Rigorous Te Solution To The Staircase Model Of The Dielectric Wedge Antenna, Wan-Yu Chen

Theses

The rigorous TE solution to the staircase model of the dielectric wedge antenna is presented. The fundamental, even TE surface wave mode of the dielectric slab waveguide is taken to excite a dielectric wedge which is formed by symmetrically tapering the slab. The method of solution is based on Marcuse's step-transition method. Radiation patterns of power gain are presented which show increased maximum power gains and narrower main lobe beamwidths for longer wedges. For higher dielectric constant material, the main lobe beamwidth is increased. In all cases examined, negligible sidelobes were obtained.