Physics: Honey, I shrunk the antenna

The next generation of antennas could be up to 100 times smaller than current compact antennas if fabricated using a novel design approach described in Nature Communications. The technology could have potential applications for portable wireless communications systems, including wearable electronics, smartphones, bio-implantable and bio-injectable antennas, and the internet of things.

Traditional antennas are rigid metal structures that are sized to be resonant with a specific wavelength of radiation, which puts limits on miniaturization. The new antenna developed by Nian Xiang Sun and colleagues is a membrane that is resonant not with a specific wavelength, but instead a specific frequency, which allows for a vast reduction in the physical size of the antenna. The membrane is composed of a thin film magnetoelectric material that changes its magnetization as it vibrates, coupling the acoustic vibration with both transmitting and receiving radiation.

The authors find that the membrane resonant frequency can be controlled by different geometric designs, and have demonstrated this technology with two different designs spanning the UHF and VHF radio frequencies. The new antennas perform better than similarly sized traditional antennas, and they are completely passive requiring simple electronics and no battery.