Metasurface Based Dual CP Antenna for S Band Communication

This article proposes a dual circularly polarized antenna with high gain, isolation and wideband characteristics. The proposed antenna consists of a microstrip patch antenna fed with 90° hybrid coupler. The gain of the parent antenna is increased from 3 dB to 7.1 dB. The high gain of 7.1 dB is due to superstrate based metasurface configuration consisting of periodic arrangement of unit cells placed on FR4 substrate and suspended by air gap with the help of non-dielectric spacers. The antenna is fabricated and measurement shows the antenna has good impedance matching across 2 to 3 GHz. The impedance bandwidth of the proposed antenna is 0.8 GHz (2.04–2.84 GHz) with fractional bandwidth of 32.78% and maximum return loss observed at 2.2 GHz and 2.7 GHz. The hybrid coupler provides LHCP and RHCP from 2–3 GHz. The antenna offers wide port isolation >13 dB. The proposed antenna can be promoted for satellite communication replacing bulk array antennas.