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