Wideband Dual-Polarized Crossed-Dipole Antenna with Parasitical Crossed-Strip for Base Station Applications

A wideband dual-polarized crossed-dipole antenna with parasitical crossed-strip for basestation applications is presented. By using a pair of orthogonal crossed-dipoles, two linear polarizations (±45◦) are obtained. A parasitical crossed-strip is introduced to improve the impendence bandwidth and enhance the isolation (S12) between the two orthogonal polarizations of the upper band. The antenna shows a wideband impedance characteristic about 34.9% for S11 ≤ −10 dB (+45◦ polarization) and S22 ≤ −10 dB (−45◦ polarization). High isolation (S12 ≤ −32 dB) between the two polarizations in the required band are obtained. The stable peak gain, unidirectional radiation patterns and low crosspolarization over the whole operating band are also achieved. Due to its good performance, simple fabrication technique and low cost, the antenna is very suitable for potential base station applications in mobile communication such as DCS, PCS and UMTS.