A Portable Very Low Frequency (VLF) 2FSK Signal Receiving Antenna Based on Magnetoelectric Cantilever

High-conductive environments such as deep Earth and seawater bring challenges to existing electronic communication technology. Very low frequency (VLF) communication technology is supposed to be a feasible solution for conductive environment communication due to its improved radiation attenuation. Herein, we report a VLF 2 frequency shift keying (2FSK) signal receiving antenna based on the Metglas/0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 magnetoelectric (ME) cantilever. The cantilever beam is predicted by finite-element simulation and shows double electromechanical resonance peaks. Experimental results reveal that the ME cantilever demonstrates strong resonant ME coupling coefficients as high as αQ ∼ 100 nC/Oe at 6 and 18 kHz, which ensures high responsivity and low bit error rate during modulation in FSK communication applications. The noise equivalent magnetic field of the whole antenna system at the resonant peak is measured to be as low as 12.56 fT/Hz1/2 (at 18.44 kHz), implying a huge signal-to-noise ratio advantage. Based on the above preparation, the ability of the ME antenna to receive a 2FSK signal is verified. The ME antenna shows good performance in demonstrating FSK signal reception, which is 200 b/s. Such a ME-composite-based mechanical antenna shows great potential in the conductive environmental communication application.