An Efficient, Electrically Small, Three-Dimensional Magnetic EZ Antenna for HPM Applications

Abstract

Metamaterial (MTM)-inspired antennas leverage techniques that have been developed over the past decade for designing artificial materials whose electromagnetic properties can be tailored to specific applications. One of the key features of the MTM-inspired antennas is their ability to motivate electrically small antenna designs through planar and volumetric loadings of space with resonant parasitic capacitive and inductive structures. In a previous work, we developed the magnetic EZ antenna as a resonant antenna that operates below <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ka</i> = 0.5. In this paper, we adapt the magnetic EZ antenna concept for use with high-power mesoband quarter-wave oscillator microwave sources that can operate with hundreds of megawatts of peak power and charge voltages in excess of 100 kV in the ultrahigh frequency (500-650 MHz) and demonstrate their performance with charge voltages up to 10 kV. The principal challenges that were overcome in this effort include field management to prevent undesired breakdown and capacitive isolation to decouple the EZ antenna from the source during the charge phase. Antenna design, modeling, and experimental verification are presented here, demonstrating an operating EZ antenna/source system at 510 MHz with antenna <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ka</i> = 0.436 . The results demonstrate that the EZ antenna is a viable antenna to consider when traditional high-power microwave antennas are too large to be integrated into a given platform.