Effect of superstrate height on gain of MSA fed Fabry Perot Cavity antenna

This article highlights the effect of superstrate height on gain of MSA fed Fabry Perot Cavity (FPC) antenna. The FPC antenna structure consists of a microstrip antenna, which feeds an array of square parasitic metal patches fabricated on a FR4 superstrate. These patches are good reflector of microwave frequency and therefore are used to enhance the reflection coefficient and the gain. Field amplitude and phase depend on dimensions and spacing between parasitic patches. Antenna gain can be further increased by increasing the superstrate height. However, differential gain improvement decreases with superstrate height. High gain is achieved by placing superstrate layer at about integral multiple of half wavelength above the ground plane. Structures are designed, fabricated and tested. Measured VSWR is less than 2 over 5.725-5.875 GHz, ISM band. The analysed structures can be packaged inside an application platform.