High gain and wideband stacked patch antenna for S-band applications

Abstract

In this paper design of a stacked circular patch antenna is presented for high gain and wideband applications. The main radiator of this design is a circular patch antenna, which is fed by using a coupling mechanism. Wide impedance bandwidth of 40% and linear polarization of gain 9.5 dBi at the center frequency of 2.4 GHz is measured. The antenna gain is further increased by using regular period of N circular patch directors on top of the main radiator. The first director is placed in a distance of about one half of the wavelength and the next directors are placed with regular distances of about a quarter of the wavelength. The antenna gain is tuned and increased with the number of the directors in the range of 9.5-16.5 dBi with N up to seventeen. The antenna impedance change due to the added directors is adjusted by using two parasitic circular patches between the main radiator and the first director. A prototype antenna is designed, manufactured and measured. The antenna operation can be further extended using dual feed geometry in which we can obtain two orthogonal radiation patterns or circular polarizations.