Emerging trends in high gain antennas for wireless communication

The design of high antennas for wireless communication is very essential. The main drawback of the microstrip patch antenna is the low gain. The Metamaterial superstrate layer along with antenna structure improves the antenna performance parameters like gain and bandwidth. Due to Ultra refraction phenomenon, radiation is concentrated normal to the patch so that unwanted sidelobes can be avoided. This review paper shows different techniques to increase the gain of the antennas such as use of metamaterial substrate or super-strate. Also substrate materials and feeding techniques of the antenna are varied to reduce the return loss. By changing the thickness of the substrate, bandwidth of the antenna is increased. Slots of the antenna are adjusted to enhance the gain and bandwidth. The main applications of the microstrip antennas are WiMax, medical imaging and radiolocation applications.