Patent ID: 8498543

Claim:
An optical communication system for transmitting digital optical signals comprising: an optical source adapted to receive a digitally encoded data signal comprising sequences of data and comprising two signal levels representing a first state and a second state of the data signal, the optical source being adapted to produce an optical signal substantially frequency modulated with frequency excursion Δν comprising a first instantaneous frequency (ν 0 ) associated to the first state and a second instantaneous frequency (ν 1 ) associated to the second state; an optical converter adapted to receive the substantially frequency modulated optical signal, the optical converter having an optical transfer function varying with frequency and including a high-transmittance region and a low-transmittance region, the first instantaneous frequency (ν 0 ) of the frequency modulated optical signal being spectrally aligned within the low-transmittance region of the optical transfer function of the optical converter; and the second instantaneous frequency ν 1 of the frequency modulated optical signal is spectrally aligned with a positive slope portion of the high-transmittance region of the optical transfer function of the optical converter, thereby converting the substantially frequency modulated signal into a substantially amplitude modulated signal.