A Ferromagnetic-Resonance Based Electrically Small Antenna with Circular Polarization

A circularly polarized electrically small antenna (ka=O.176) based on ferromagnetic resonance is presented at 3.352 GHz, with a radiation efficiency of 12.36%, realized gain of -7.13 dB, and a cross-polarization ratio of 35.91 dB. Because the resonant frequency of the antenna can be rapidly changed with the biased magnetic field, the design has the potential to be integrated with direct antenna modulation for realizing a large efficiency-bandwidth product on electrically small antenna.