An Architecture Analysis for Millimeter-Wave Optically Steerable Antenna Array

A lens-based integrated photodiode-antenna array for a Radio over Fiber (RoF) 5G wireless base station at millimeter-wave frequencies is proposed and analyzed. The elements of the array are based on slot bow-tie antennas which ensure a good matching to the photodiode impedance measurements in a band that extends from 23 to 35 GHz. Simulated far-field patterns show that beam steering in 23.5° steps with a minimum peak gain of 15.8 dB may be achieved by means of an optical switch in a 4-element array with 3.8 mm spacing using an Acrylonitrile Butadiene Styrene (ABS) extended hemispherical lens with 25 mm radius.