Gain Enhancement of a Broadband Symmetrical Dual-Loop Antenna Using Shorting Pins

A broadband symmetrical dual-loop antenna with enhanced gain is proposed in this letter. It comprises a symmetrical dual-loop radiator, a pair of magneto-electric feeding structures, two metal shorting pins, and a metal ground plane. To simultaneously broaden its impedance bandwidth and improve its radiation patterns, a symmetrical dual-loop radiator excited by a pair of magneto-electric feeding structures is introduced. By loading shorting pins between the radiator and the ground plane, the peak gain can be significantly enhanced over the band of operation. Measured results demonstrated that the proposed antenna has a wide impedance bandwidth of 48.2% ranging from 1.68 to 2.76 GHz for VSWR < 1.5 and a stable gain of 10.0 ± 0.85 dBi. Moreover, stable radiation patterns and low cross polarization are obtained in the desired frequency band. Due to these performances aforementioned, the proposed antenna is very suitable for base station applications.