An RF antenna feed module uses an optical feed network and photo-detectors to generate RF feed signals to drive a dual polarization RF antenna to produce an RF beam with a variable polarization state. The optical feed network and suitably the photo-detectors are monolithically fabricated PIC. Multiple modules may be configured to drive a dual polarization RF phased array. A single feed module can produce RF feed signals over a frequency range of at least 300 GHz.