A Compact Dual Broadband Shared-Aperture Antenna Array for 5G Base Station Applications

A compact dual broadband dual-polarized shared-aperture antenna array is proposed for base station applications. The shared-aperture antenna array consists of a dipole antenna operating at the lower band (LB) of 0.69-1.52 GHz, and a 2×2 antenna array operating in the higher band (HB) of 2.3-5 GHz. Low-pass partially reflective surfaces are introduced for the shared-aperture antenna to eliminate the influence of the LB antenna on the HB antenna array. The overall size of the antenna is about $0.30 \lambda_{L} \times 0.30 \lambda_{L} \times 0.17 \lambda_{L}(\lambda_{L}$. is the free-space wavelength of 0.69 GHz). The dual broadband shared-aperture antenna array achieves stable radiation patterns with average gains of 8 dBi for the LB antenna and 11 dBi for a column of two elements of the HB antenna. Owing to the dual broad bandwidth, low profile, and shared aperture, the proposed antenna array is promising for Sub-6 GHz mobile communication applications.