Field-tunable low-frequency magnetoelectric antennas for non-line-of-sight communication

Abstract

Acoustically actuated low-frequency magnetoelectric (ME) antennas have been widely concerned and reported in special environments communication, such as underwater, underground, and through wall, owing to its small size. However, the practical radiation properties of ME antennas are different from those in the theoretical model because the nonlinear coupling effects on radiation performances caused by the external field have not been paid enough attention. This work focuses on the influence of external field on the optimization of radiation and communication performance of ME antennas. The results show that the appropriate external field conditions can significantly improve the converse ME coupling coefficient and radiation intensity of ME antennas. At room temperature 26 °C, the radiation intensity of the antenna reaches the maximum value of 21.2 nT at 1 m under the magnetic bias field of 360 Oe, which increases by 116% compared with 100 Oe. The radiation intensity reaches 31.1 nT at 1 m increased by 77.9% via increasing the operating temperature from 0 to 90 °C. The maximum modulation rate of through-wall communication can reach 800 bps by tuning the external field using amplitude shift keying modulation, which confirms the communication reliability of the ME antenna in non-line-of-sight scenes. Our work not only illustrates the physical mechanism of tuning the performance of ME antennas by external field but also verifies the practical application potential of ME antenna in communication in strong attenuation scenes.