Patent ID: 8064776

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 at a data rate (B) 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 at least one pass band, the at least one pass band having a peak transmittance and at least a low-transmittance region, wherein the first instantaneous frequency (ν 0 ) of the frequency modulated optical signal is spectrally aligned within the low-transmittance region of the optical transfer function of the optical converter thereby converting the substantially frequency modulated signal into a substantially amplitude modulated signal and the at least one pass band has a FWHM comprised between 70% and 200% of the data rate (B) of the frequency modulated optical signal.