A Triple-Band Open-Slot Antenna with Linear and Circular Polarizations

Abstract

A uniplanar open-slot antenna with triple-band operation and linear and circular polarizations has been presented in this work. We etched two open slots in the ground plane as the radiator elements. By utilizing a T-shaped feeding stub, the inductive reactance of the open-slot antenna can be compensated by a capacitive loading such that the moderate impedance bandwidth can be obtained. By etching the inverted-L slit in the top segment of the ground plane, the circular polarization around 2.33 GHz can be excited. An inverted-C coupling strip is embedded in the dominant open-slot radiator to enhance the impedance matching condition in the middle frequency band. Additionally, by using this technique, a new resonance around 5.3 GHz is excited. Parametric studies on geometries of the inverted-L slit and the inverted-C coupling strip are conducted to associate performance features with some specific antenna dimensions.