A compact dual-polarized magneto-electric dipole antenna for 2G/3G/LTE applications

A compact ±45° dual-polarized magneto-electric (ME) dipole base station antenna is proposed for 2G/3G/LTE applications. The antenna is excited by two Γ-shaped probes placed at a convenient location and two orthogonally octagonal loop electric dipoles are employed to achieve a wide impedance bandwidth. A stable antenna gain and a stable radiation pattern are realized by using a rectangular box-shaped reflector instead of planar one. The antenna is prototype and measured. Measured results show overlapped impedance bandwidth is 58% with standing-wave ratio (SWR) ≤ 1.5 from 1.68 to 3.05 GHz, port-to-port isolation is large than 26 dB within the bandwidth, and stable antenna gains of 8.6 ± 0.8 dBi and 8.3 ± 0.6 dBi for port 1 and port 2, respectively. Nearly symmetrical radiation patterns with low back lobe radiation both in horizontal and vertical planes, and narrow beamwidth can be also obtained. Moreover, the size of the antenna is very compact, which is only 0.79λ₀ × 0.79λ₀ × 0.26λ₀. The proposed antenna can be used for multiband base stations in next generation communication systems.