Dual-polarized turning torso antenna array for massive MIMO systems

A compact dual-polarized antenna with four radiating square patches is presented and arranged to establish an array for massive MIMO systems operating at 3.7GHz. There are three stack levels of orthohexagonal rings in the array and each ring contains six sub-arrays with a gain of 16.6dBi and half-power beam width of 12.5° in azimuth. Within a volume of 8λ×8λ×3λ, the maximum mutual coupling level between any two ports in the array is lower than -29dB. With the steerable feature of each beam formed by sub-array, the proposed array can generate 18 beams covering around a whole circumference.