Reconfigurability of frequency band and polarization in broadband log-periodic slot antennas

This thesis focuses on the design of a toothed planar log-periodic slot antenna with two different kinds of reconfigurability using two novel techniques. To attain a reconfigurable frequency band, diode switches and DC-isolating slots were added to shift the band upward an octave when switches are closed. To give the antenna reconfigurable polarization, a rotated copy of the structure was put in place so that two antennas lay in the same ground plane in a cross formation, and a modification to the feed structure was made to provide adequate isolation between the two. The result is an antenna capable of providing dual linear polarization or circular polarization, depending on how it is fed. Theoretical simulations were carried out using the method of moments technique via the commercial software package Ansoft Ensemble. Some models were implemented in hardware as well using a T-Tech milling machine. Results were measured on a network analyzer to show simulation validity.