High Gain and Wide Band Antenna Based on FSS and RIS Configuration

In this paper, a novel technique using frequency selective surface (FSS) superstrate is proposed to increase the antenna gain. In addition to that, a combination of reactive impedance surfaces (RIS) is included to enhance the bandwidth. So, a conventional pentagon shape patch antenna is designed at 5.3 GHz. The frequency selective surface is designed as a 6 x 6 array of unit cell structures to operate around 5.3 GHz. Each unit cell consists of three metal conductive layers with substrates in between them. Reactive Impedance Surface is considered as an array size of 6 x 6 square patches embedded between two substrates. FSS is designed on Rogers 4003C and FR4 is used for RIS. The pentagon shape patch antenna is designed on RIS. A cavity created by the contribution of these layers acts like a Fabry Perot resonator which improves the gain and bandwidth simultaneously. The proposed antenna has an impedance bandwidth of 17.72% (4.93-5.89 GHz); this is about a 10 percent improvement over the impedance bandwidth of a conventional pentagon shape antenna and the axial ratio bandwidth is 2.4% (5.01-5.14 GHz). The designed antenna gain is around 12 dBi; this is about a 9dBi improvement over the gain of a conventional pentagon shape antenna.