Development of a compact resonant magnetoelectric ultra-low frequency multiferroic transmitter

Abstract

This work investigates a compact, resonant magnetoelectric transmitter for near-field communication in RF-denied environments. The transmitter leverages a Tonpilz-type resonator, employing a laminated Galfenol bar mechanically coupled to a single crystal 0.24Pb(In1/2Nb1/2)O3–0.46Pb(Mg1/3Nb2/3)O3–0.30PbTiO3 (PIN–PMN–PT) piezoelectric element. Driven at its longitudinal resonance mode around 4 kHz, the piezoelectric element induces stress in the Galfenol bar, generating a magnetic dipole field via the magnetostrictive effect. Rigorous characterization, including impedance, quality factor, internal dynamic flux, and transmitted magnetic signal measurements, was performed. Notably, the device’s resonant frequency can be tuned within the 3–6 kHz range by adjusting the DC bias voltage applied to the piezoelectric element or by modifying the compressive prestress. Operating at resonance yields a tenfold amplification of the magnetic dipole signal, which extrapolates to a radiative field strength of approximately 1 fT at 100 m requiring only 0.637 Wrms of power. Strong agreement between experimental data and theoretical models highlights the critical role of device geometry in optimizing the transmitter design for enhanced field generation.