Investigation on Compact, High Gain Microstrip Antenna Providing Multifrequency Operation

Simulated and experimental investigations on a compact, single layer and single probe fed circular Microstrip patch antenna with multi-frequency operation are presented in this paper. This novel design is achieved by cutting four rectangular slots at ground plane of Microstrip patch antenna. Generally Microstrip antenna exhibits narrow bandwidth and single or dual frequency operations. After modifications researchers have been able to design the antenna to have broad band, compactness or multi frequency operation or any one of them. However in this paper two characteristics have been achieved simultaneously. One is compactness and other is multi frequency operation. Compared to the conventional circular patch antenna the proposed antenna can achieve 94% size reduction. Septa frequency operation has also been achieved effectively by adjusting the number of circular ring, their size and feed position. Simulated investigations are done by Ansoft Designer software based on method of moment. Measurement is done using standard microwave test bench.