A Compact and Wideband Dual-Polarized Antenna Using Folded Loops

A novel dual-polarized antenna using folded loops is presented in this paper. The proposed dual-polarized antenna is composed of four triangle loops, which is developed from a single polarized antenna with two triangle loops. By using folded method, a linear polarized loop antenna is elaborately transformed into a dual-polarized antenna with the only increase of feed port for another polarization. Design method of the proposed dual-polarized antenna is discussed and illustrated in this paper. By virtue of the folded design method, the proposed antenna shows a compact size compared to the referenced designs. In addition, wide impedance bandwidth is also achieved with simple configuration. To demonstrate the design method, the proposed antenna is implemented and measured. The measured results prove that the antenna has a wideband impedance bandwidth for base stations with VSWR<1.5 and isolation >35 dB from 1.7 GHz to 2.7 GHz. Furthermore, stable gain and HPBW are also obtained for base station applications.