Broadband Electrically Small Antennas with Strain Powered Multiferroics

ORAL

Abstract

Antennae built from magnetic materials offer a promising concept for reducing antennae’s size to below free space wavelengths (i.e. < λ/50). However, recent studies on strain mediated multiferroic antenna heterostructures show only narrow band operation. To overcome this issue, we studied a system consisting of a magnetoelastic single domain disk placed atop a piezoelectric substrate. The spinning magnetization radiates electromagnetic energy into free space over broadband frequencies, i.e. from very-high frequency to ultra-high frequency. The magnetization is driven with patterned electrodes with periodic input voltages, which produce strain that couples to the magnetoelastic media. Two magnetoelastodynamic modeling approaches were used; one within a micromagnetic finite element formulation and the other in a macro spin framework. The free space radiation is modeled by considering two orthogonal magnetic dipoles rotating out of phase.
We studied magnetic materials with frequencies ranging from 10 MHz to 2 GHZ, which show similar results for the dynamics. These results are used in an analytical formulation to predict radiation power densities of ~mW/m2. Arraying these elements produces larger radiation magnitudes, suggesting a new path for creating small broadband antennae.

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Presenters

  • Jin-Zhao Hu

    MAE Department, UCLA, Univ of California - Los Angeles

Authors

  • Jin-Zhao Hu

    MAE Department, UCLA, Univ of California - Los Angeles

  • John Domann

    Department of Biomedical Engineering and Mechanics, Virginia Tech, MAE Department, UCLA

  • Scott Keller

    MAE Department, UCLA

  • Greg Carman

    Department of Mechanical and Aerospace Engineering, UCLA, MAE Department, UCLA, Mechanical and Aerospace Engineering, University of California, Los Angeles, Mechanical and Aerospace Engineering Department, University of California, Los Angeles, Mechanical and Aerospace Engineering Department, Univ of California - Los Angeles, Univ of California - Los Angeles, Department of Mechanical and Aerospace Engineering, University of California, Los Angeles

  • Abdon Sepulveda

    MAE Department, UCLA, Mechanical and Aerospace Engineering, University of California, Los Angeles, Mechanical and Aerospace Engineering Department, University of California, Los Angeles, Mechanical and Aerospace Engineering Department, Univ of California - Los Angeles, Univ of California - Los Angeles