Radiation-enhanced acoustically driven magnetoelectric antenna with floating potential architecture

Abstract

A magnetoelectric (ME) antenna driven by a high-overtone bulk acoustic resonator (HBAR) can play a potentially positive role in the bandwidth enhancement benefit from its narrow harmonic frequency interval, in which radiation characteristics remain to be explored. HBAR ME antennas with floating potential architecture (FPA) and grounded are fabricated and demonstrated separately. The measured far-field radiation characteristics show that the FPA can significantly enhance the gain and radiation efficiency of the HBAR ME antenna by more than 10 dB compared to the grounded setup. Meanwhile, the time domain amplitude sweep demonstrates the high-power tolerance (>23.2 dBm) of the HBAR ME antenna. Two-dimensional finite element method analysis reveals that the FPA-induced electric field excites additional longitudinal-wave resonance, resulting in the coupling of dual longitudinal and shear waves, which is the intrinsic mechanism of its radiation enhancement from the perspective of acoustic excitation. Not only limited to HBAR antennas, the mechanism of FPA described here is also a promising candidate for radiation enhancement in acoustically driven antennas.