Improvement in Characteristics of Microstrip Patch Antenna with the Help of Zero Index Metamaterial Structure

In planar antennas, the metamaterial superstrate based designs are very demanding for high-gain antenna applications. In this paper, a new metamaterial unit-cell with a zero refractive index (n) is presented and employed for the gain enhancement of a microstrip antenna operating at 5.28GHz. The unique property of the metamaterial gathers the wave radiated from the antenna and collimates it towards the normal direction when used in a superstrate layer. The design provides a gain enhancement of 8.1dB using a single layer superstrate, when suspended above a microstrip patch at 5.28GHz.