Patent attributes
An apparatus includes a first light source to produce a first reference light, a first pair of arrayed waveguide gratings (AWGs) to demultiplex a first optical signal and the first reference light, respectively, into multiple first signal beams and multiple first reference beams. A first heterodyne optical detector can mix the multiple first signal beams and the multiple first reference beams to generate first quadrature optical signals. A first pair of photo-detectors can convert the first quadrature optical signals to first in-phase (I) and quadrature (Q) electrical signals. The apparatus is implemented as a photonic integrated circuit (PIC) incorporating the first pair of AWGs, the first heterodyne optical detector and the first pair of photo-detectors.