A Compact Ultrawideband Diversity Antenna With High Isolation

A compact ultrawideband (UWB) polarization diversity antenna with high isolation is designed in this letter. It comprises a step-tapered slot antenna (S-TSA) and a small square monopole antenna with an inverted H-shaped slot and an H-shaped conductor-backed plane. The isolation between the two ports is improved due to the orthogonality of E-field of two elements. The designed antenna has a small size of 26 × 38 mm
²
. The measured results show that it can operate from 3.1 to 10.6 GHz, in which the average isolation is better than 30 dB.