A Triple Band Microstrip Patch Antenna

Abstract

Microstrip Patch Antennas (MSA) are used at dominant mode and rarely used at the higher order modes because of the differences in the radiation pattern etc. In this paper, we have proposed a MSA which consists of a center patch and two slender patches on both sides, each connected to the center patch by two short microstrip lines. This MSA can have a main beam in the boresight direction at three frequencies corresponding to the frequencies of the dominant, the second, and the third modes.
The optimum structural parameters are sought by the numerical simulation using HFSS of Agilent Co. in order to obtain as high power gain as possible at the boresight direction. The MSA with thus determined parameters is manufactured and tested. The experiment verified that the proposed MSA can have a unidirectional radiation pattern at three frequencies similar to that of the conventional MSA working at the dominant mode frequency.