Proximity-coupled and dual-polarized microstrip patch antenna for WCDMA base station arrays

A novel dual-polarized microstrip patch antenna is presented. The antenna uses proximity-coupled microstrip feed lines along the patch corners and covers the full WCDMA/UMTS band with only a single radiating patch. The corner-fed patch arrangement results in two orthogonal linear polarizations along the patch diagonals with high isolation. The presented antenna can be applied in dual-slant polarized base station antenna arrays. The measured input matching of both ports at TX&RX bands of 1920-1980 MHz and 2110-2170 MHz is below -13.8 dB and the polarization isolation is more than 30 dB. Measured gain is about 10 dBi, and half-power beamwidths in the horizontal plane about 45deg -55deg . Cross-polarization is better than -22.5 dB.