Design of modified reconfigurable RIS and its application in patch antenna miniaturization

This paper proposes the use of a modified frequency reconfigurable Reactive Impedance Surface (RIS) for miniaturization of patch antennas. A periodic array of square patches with slot etched within has been used to realize the RIS. The imaginary impedance of the RIS when used as antenna ground plane has been explored to achieve miniaturization. The RIS however uses a thin substrate maintaining low profile of the antenna. The resonant frequency of the antenna shifted to a lower value giving 21.6% miniaturization and also impedance bandwidth of 205MHz which is a significant improvement compared to PEC backed patch antennas. The antenna also shows stable radiation pattern in both E plane and H plane with a peak gain of 8dBi and radiation efficiency 85%.