A CPW-Fed Slot Antenna for Multiple Wireless Communication Systems

In this paper, a wideband CPW-fed slot antenna based on the L-shaped is proposed. In order to simplify the antenna configuration and fabrication process, the slot antenna and the feeding structure are etched on the same plane of the substrate. By changing the geometry of the L-slot, an additional mode with two orthogonal electrical fields with 90 degree phase difference is excited, thus causing the circularly polarization (CP). Furthermore, introducing a protruded stub at the feedline, adding one finger slit and tuning the dimension of the ground plane improve the impedance matching condition. Finally, after the size optimization, the measured bandwidth of 22% (2.23-2.78 GHz) is achieved with an axial ratio <; 3 dB.