Uniplanar Slot Antenna for Ultrawideband Polarization-Diversity Applications

A uniplanar slot antenna for ultrawideband (UWB) polarization-diversity applications is presented. The antenna consists of an annular slot and orthogonal feeding mechanisms to achieve polarization diversity performance across the UWB from 2.8-11 GHz. By introducing a cross-shaped strip diagonally between the two U-shaped stubs, an interport isolation better than 14 dB is accomplished except at the lower and higher frequency end. The notch band from 5.0-6.3 GHz is realized by embedding arc-shaped slot resonators on the feeding structures. The proposed antenna facilitates nearly omnidirectional radiation pattern, low envelope correction coefficient, moderate gain, and efficiency. Moreover, the time-domain analysis displays minimum dispersion to the radiated pulse. All these features make the proposed antenna a good candidate for future wireless communication systems with polarization-diversity operation, where the challenge such as multipath fading is a major concern.