Improving radiation performance of low-frequency magnetoelectric antennas based on structure–circuit coupling

To address the technical challenge of narrow bandwidth in low-frequency magnetoelectric (ME) antennas, existing solutions, which primarily rely on structural optimization, have not favored a compact antenna design. In response to this issue, this paper introduces a novel approach based on a structure–circuit coupling to broaden the bandwidth of ME antennas. By incorporating an inductor into the antenna circuit to induce an additional electrical resonance, which interacts with the antenna's inherent electromechanical resonance, we achieve multiple resonant modes. Through the development of a structure–circuit coupling simulation model, we investigate the impact of circuit parameters on the antenna's resonance characteristics, uncover the mechanism of the multi-resonant mode, and identify optimal parameter conditions. The effectiveness of the proposed method is validated. Our findings reveal that when the added inductor value is 13 mH, the operating frequency band, corresponding to a ME coefficient of 30.11Vcm−1Oe−1 (compared to the coefficient value at the 3 dB bandwidth without the inductor), is expanded by 942%. This research holds the potential to provide new theoretical insights for the optimization of ME antennas.