A Compact, Dual-Polarized Multiband Array for 2G/3G/4G Base Stations

A compact, dual-polarized multiband array is proposed and developed for 2G/3G/4G base station applications. The antenna is formed by two-element lower band array, five-element higher band array, bowl-shaped reflectors, bended baffles, and rectangular baffles, which are coexisting over one reflector. Miniaturized higher band element covering 2G/3G/4G bands and new square-shaped aperture lower band element covering LTE700/GSM850/GSM900 have been proposed. The higher band elements are placed upon the bowl-shaped reflector and composed of two pairs of loop dipoles with chamfers and vertical stubs for miniaturization. The bowl-shaped reflector is of great significance to the stable beamwidth, while the rectangular and bended baffles are designed further to improve the beamwidth. Moreover, the five-element higher band array is designed with electric downtilt from 0 degrees to 10 degrees. The measured results determined by VSWR < 1.7 are with the whole broadband coverage from 0.698 to 0.96 and 1.7 to 2.7 GHz, which can cover the whole 2G/3G/4G bands. Furthermore, the stable half-power beamwidth of 65.9 +/- 4.3 degrees at the horizontal plane (H-plane) as well as stable gain and enhanced cross-polarization discrimination (XPD) are achieved within both higher and lower frequency bands.