Dual-Polarized Wide-Angle Scanning Phased Array Antenna for 5G Communication Systems

Abstract

A dual-polarized phased array antenna is presented with wide-angle scanning capability in this article. To improve the mutual coupling in the array, a current cancellation method (CCM) is proposed by changing the current distribution on the excited unit to induce a pair of the canceled currents on the adjacent unit. Meanwhile, this current distribution broadens the beamwidth of the unit in the array. Besides, the proposed method can also optimize the array unit size and achieve a small inter-unit distance for wide-angle scanning capability. A low-profile dual-polarization antenna operating in the bandwidth from 4.4 to 5.0 GHz is designed as a linear array and a planar array to verify the proposed method. Regardless of the linear array or planar array, the mutual coupling in the array is below −19 dB, which is better than that in conventional arrays. Meanwhile, the antenna unit in the array can radiate a wide-beam pattern. Two arrays can scan over ±60° for both polarizations. Within the scanning range, the realized gain reduction is less than 3 dB and the sidelobe level is lower than −7.5 dB. To verify the performance, two array antenna prototypes are fabricated and tested. The experimental results agree well with the simulation.