Reconfigurable and multiband antennas with resonant and reactive loads

Abstract

Reactive and resonant loads have been used from the very beginning of antenna design to improve impedance matching, bandwidth, and current distributions on antennas, and to create multiband and reconfigurable antennas.Trap loaded dipoles are one of the simplest resonator-loaded antennas and are traditionally loaded with either an inductor-capacitor pair or a quarter wavelength stub integrated into a dipole or monopole to create a second operating frequency at the trap resonant frequency. Adding resonant loads to antennas will only increase in popularity and practicality as filtennas are more often used for their SWaP improvements, better noise performance, and potential for additional degrees of reconfigurability. In this dissertation, I demonstrate that resonant loads can introduce lossy modes, and I significantly revise and expand the theory of the basic trap dipole antenna, which is a valuable aid in designing resonator loaded antennas with higher degrees of complexity. Based on the new analysis, I demonstrate novel series LC trap dipoles, dual-band inductor loaded trap dipoles, and parallel and series LC trap slots. The newly developed design process also allows for the integration of any kind of resonator or reactive load to be used to create trap style antennas. A reconfigurable load is also used to demonstrate novel tunable trap antennas. The design procedure is ultimately adaptable to any resonators that can be practically fabricated and physically incorporated into the antenna structure.