Recently, a new type of antenna, bulk acoustic wave (BAW)-mediated multiferroic antenna, has been proposed based on thin-film bulk acoustic resonators (FBARs). The underlying principle is using mechanical wave coupled into EM radiation. It’s expected to outperform traditional electrically small antenna by orders of magnitude. My research is to implement agile polarization control over EM radiation excited by mechanical coupling from multiferroic materials.

• Related publication: Experimental validation of multiferroic antennas in GHz frequency range (R.-F. Xu et al., "Experimental validation of multiferroic antennas in GHz frequency range," Applied Physics Letters, vol. 123, no. 16, 2023, doi: 10.1063/5.0165393.)

Researcher: Rui-Fu Xu (許瑞福)

The need of multipath effects reduction and precise polarization alignment have propelled circularly polarized antennas to satellite and wireless communication system applications.  To further enhance the performance, antennas with polarization agility have been widely used in the communication systems with respect to polarization diversity. The research is polarization reconfigurable circularly polarized antenna with focus on wide axial ratio bandwidth and the simplicity of DC biasing design.

Researcher: Yun-Ting Tsai (蔡昀廷)

The aim of this project is to develop a new kind of miniature resonant antennas using mechanical waves as radiation mechanism. The operating mechanism uses magnetic currents as source of radiation. An antenna using magnetic currents as source needs materials that provides a time variation of a magnetic field or magnetization, that is ''magnetic materials‘’. Using the concept of indirect magnetoelectric effect, an applied AC electric field on electrodes moves a piezoelectric material sandwiched in between, the generated mechanical waves propagate into the magnetostrictive layer which transforms the mechanical waves into a time varying magnetization, generating radiation. These antennas could achieve micro to nanometric scales, making them suitable for new non-invasive biomedical chips that could be used for brain analysis. 

Researcher: Louis-Charles Ippet-Letembet (歐祿益)