An optical digital-to-analog (D/A) converter and a method of optically
converting digital data into analog form. In one embodiment, the optical
D/A converter includes: (1) a splitter configured to receive and split an
input coherent optical carrier into a plurality of mutually coherent
optical carriers, (2) a switching stage coupled to the splitter and
including a corresponding plurality of selector switches configured to
pass or interrupt selected ones of the plurality of coherent optical
carriers responsive to pattern bits, (3) an amplitude and phase offset
stage coupled to the switching stage and including a corresponding
plurality of amplitude and phase offset units configured to offset
amplitudes or phases of passed ones of the plurality of mutually coherent
optical carriers responsive to offset signals and (4) a combiner coupled
to the amplitude and phase offset stage and configured to recombine the
mutually coherent optical carriers to yield an optical output signal.