Miniaturized dual-polarized ultra-wideband tapered slot antenna

A compact dual-polarized tapered slot antenna is proposed for ultra-wideband (UWB) through-wall imaging applications. The dual-polarized antenna is obtained by shifting one single-polarized element orthogonally into the other one. The miniaturization of the antenna is realized by employing a folded balun comprising a folded slot on the right side of the radiator and a stepped microstrip line is used for improving the impedance matching. In addition, the fabrication complexity of the antenna is reduced due to the use of a folded balun. The antenna occupies a small size of 30 × 30 × 16 mm³. Both simulated and measured results confirm that it can achieve a wide impedance bandwidth from 3.1 to over 12 GHz. Both ports have similar radiation characteristics with an isolation of 20 dB and the gain response is varying from 2.5 to 6.8 dBi.