A Cross-Band Coupling Suppressed Tri-Band Base Station Array With Simultaneously Wideband Decoupling and Radiation Characteristics

The simultaneous realization of wideband radiation and wideband cross-band decoupling in current 5G tri-band base station array remains a critical technical impediment. To address this challenge, a cross-band coupling suppressed tri-band base station antenna array based on radiative deep-subwavelength frequency selective surface (RFSS) with wideband decoupling and wideband radiation characteristics is proposed. The designed array consists of a low-band (LB) antenna operating in the range of 0.69–0.96 GHz (32.7%), a 2×2 middle-band (MB) antenna subarray operating in the range of 1.4–2.7 GHz (63.4%), and a 4×4 high-band (HB) antenna array operating in the range of 3.3–3.8 GHz (14.1%). In this configuration, the LB and MB antennas improve the radiation pattern distortions in 1.4-3.8 GHz (92.3%, which covers the bandwidth of MB and HB) and 3.3–3.8 GHz, respectively. A prototype for proof of the tri-band array is fabricated and measured. Experimental results confirm that the tri-band array exhibits the capability to achieve cross-band decoupling within wideband operational bandwidths.