Novel size-reduced circularly polarized antennas

This thesis presents an investigation into techniques for reducing the size of low-profile antennas while at the same time achieving good antenna performance. Two novel compact single fed L-band circular polarized antennas are investigated: the cross aperture fed dielectric loaded microstrip patch antenna and the coplanar fed dielectric resonator antenna. Two size reduction methods were used to make these antennas more compact. The novel dielectric loading technique reduces the resonant frequency of the microstrip patch by loading high permittivity dielectric pieces on the ground plane and beneath a suspended aperture-coupled microstrip patch. The second method utilizes a novel and compact coplanar waveguide to excite the dielectric resonator antenna with the traditional size reduction technique of increasing the relative permittivity of the dielectric resonator.; Detailed analysis and characterization of the circular polarized prototypes was performed. The effects of varying the design parameters such as the dimensions, permittivity and center positioning of the loaded dielectric pieces and the permittivity of the dielectric resonator were investigated. (Abstract shortened by UMI.)...