Gain Enhancement of Slot Antenna Using Laminated Conductor Layers

A CPW fed slot antenna on FR4 substrate has been designed to resonate at 5GHz. The gain of the designed antenna has been improved by adding very thin layers of dielectric coated with metal. The layers have same area as that of the substrate and are added directly on the ground plane of the antenna. Gain of the antenna increases gradually with subsequent addition of laminated conductor layers. After adding 5 layers, the gain of the original antenna increases form -0.98dB to 4.62dB. Effect of the thickness of dielectric layers, dielectric constant of the dielectrics and the number of laminated conductor layers on gain and resonant frequency have been investigated. Ansoft HFSS v 14 has been used for simulations. The antenna shows stable radiation pattern with acceptable cross polarization level even after addition of laminated dielectric layers.