Design of a Composite Decoupling Structure for Dual-Band Dual-Polarized Base Station Array

A composite decoupling structure is proposed to ameliorate the mutual couplings for dual-band dual-polarized base station array. The structure consists of dual-band decouple surface combined with staggered dielectric surface and several meandered line resonators embedded on the ground. The proposed decoupling structure achieves synchronously reduction of c-pol E-plane, H-plane, and x-pol couplings. In this letter, a staggered 2-1-2 array integrated with the proposed decoupling structure is simulated and measured. The results demonstrate that the decoupled array is operating in the 3.3–3.7 GHz (B1) and 4.8–5.5 GHz (B2) bands with VSWR better than 1.5 and the isolation can be improved to 20 dB in B1 band and 25 dB in B2 band even higher. The radiation patterns of the decoupled array are well maintained with about 20% (B1) and 5% (B2) total efficiency improvement, and the envelope correlation coefficient of the ports is decreased from above 0.02 to less than 0.003 over the whole operating bands. The proposed scheme has potential application prospects in massive multiple-input–multiple-output and fifth-generation (5G) communication systems.