Photonically Assisted 2-D Transmit Array Using Fourier-Optic-Based Beamformer

This article presents the development and demonstration of a photonically actuated ultrawideband (UWB), 2-D transmit array using a Fourier optical lens as a beamformer. The transmitted beam direction is selected using a beam-space optical fiber array fed through an optical switch matrix. A data encoding scheme was developed, in which custom intermediate frequency (IF) signal/data can be modulated on phase-locked tunable optical paired sources (TOPSs). A 2-D RF front-end, consisting of a tapered slot array (TSA), medium power amplifier (MPA), and needle-packaged photodetector (PD) arrays, was also developed. Experimental measurement of the far-field pattern of the developed system was conducted to demonstrate 2-D wide angular beam steering over an ultrawide frequency band from 10 to 20 GHz.