Resonator-Loaded Broadband Antenna for LTE700/GSM850/GSM900 Base Stations

A resonator-loaded broadband antenna is proposed, which is composed of a resonator-loaded dipole, a balun, a U-shaped strip feed, and a box-shaped reflector. The resonator beside the dipole is adopted for impedance bandwidth enhancement. The higher resonate modes can be moved lower by using a resonator, and wide bandwidth can be achieved by moving this mode close to the main resonating mode of the dipole. A prototype of the proposed antenna is designed, fabricated, and tested. Measured results show that the antenna achieves an impedance bandwidth of 37.5% (0.67-0.98 GHz) for |S
₁₁
| <; -15 dB.