A Dual-Band Metasurface-Based Antenna with Shorting Pins

A dual-band metasurface (MTS)-based antenna can be realized by composite right-/left-handed (CRLH) structures for wireless power transfer or ambient wireless energy harvesting. The bandwidth in the right-handed (RH) region can be obtained by exciting different desired transverse magnetic (TM) modes while that in the left-handed (LH) region can be achieved by mushroom radiating structures. The position choice of shorting pins in mushroom structures is significant since it will not only affect the potential bandwidth in the RH region, but also be related to the resonant frequencies in the LH region. The positions of the shorting pins will be chosen where the Electric field distribution is minimal for modes excited in the RH region. The proposed dual-band MTS-based antenna with an overall size of 0.375
$\lambda_{0}\times 0.375 \lambda_{0}\times 0.035\ \lambda_{0}$
can achieve 25% and 48% fractional bandwidths, and 5.0 and 9.6 dBi peak gains in the lower and higher frequency band, respectively.