A Portable Very Low Frequency (VLF) Communication System Based on Acoustically Actuated Magnetoelectric Antennas

TLDR

The system uses strain‑mediated acoustic resonators as magnetoelectric antennas operating at electromechanical resonance in the VLF band, with predicted magnetic field propagation up to 100 km. The prototype achieved a 120 m communication range with 400 mW power at 80 V, demonstrated dipole‑like near‑field radiation, matched predicted magnetic field distribution, and enabled direct antenna modulation.

Abstract

A novel very low frequency (VLF) communication system using one pair of magnetoelectric (ME) antennas has been proposed. The ME antennas are strain-mediated acoustic resonators operating at their electromechanical resonance in the VLF band. The measured near-field radiation pattern reveals ME antennas are equivalent to dipole antennas. The magnetic field radiated by the ME transmitter has been predicted along with distance ranging from 1 mm to 100 km. The measured magnetic field distribution coincided well with the prediction, and the maximum communication distance of 120 m has been achieved. With 80 V driving voltage, the power consumption of the ME transmitter has been measured as 400 mW. Furthermore, the direct antenna modulation (DAM) has also been successfully demonstrated on the ME antennas.