Potentials of Metasurface Technology on Antennas and Propagation

In this talk, some potentials of metasurface technology for antennas and propagation technology is presented. As the beginning part, some metasurface techniques and applications are reviewed. After that, some interesting techniques are presented, including some study examples in the authors' group. A metasurface (MS) has periodic arangment of unit cells in a planar shape. Such arrangements can have an artificial magnetic conductor (AMC) characteristics with an in-phase reflection coefficient at a particular frequency. Many studies on AMCs have been conducted for realizing low-profile antennas and extending the bandwidth. AMCs have been applied to expand the impedance bandwidth. In addition to the AMC characteristics, the AR bandwidth can be extended with an MS that converts linear polarization (LP) to circular polarization (CP) in the off- band for 3-dB AR. Conversion techniques of polarization to cross-polarization and from LP to CP have been extensively studied.In addition to the reviews mentioned above, some recent techniques on MS will be presented. They are mainly the projects in the authors ' group that are relevant to such as broadband antenna designs, polarizers, and propagation with MIMO. For example, the edge design of the finite size of metasurface gives a significant effect on the broadband polarization conversion techniques. Potentially the available bandwidth at a center frequency reaches 40%. Furthermore, using a metasurface can enhance channel capacity on MIMO. Some future scope of MS will be discussed.