Patent ID: 7542683

Claim:
A method for transmitting a binary base signal through an optical fiber, comprising: modulating a laser with a binary base signal having a bit period T, and generating a first signal from the laser, wherein the first signal is frequency modulated having a frequency excursion, Δυ; reshaping the first signal into a second signal, wherein the second signal is amplitude modulated and frequency modulated; and directing the second signal into the optical fiber having a transmission fiber length, L, in km and a dispersion, D, in ps 2 /km; characterized in that: the frequency excursion of the first signal, Δυ, in GHz is substantially equal to the ratio of the bit period of the digital base signal, T, in picoseconds, to the product of the transmission fiber length, L, and the dispersion of the transmission fibers, D, whereby to reduce the bit error rate at transmission distance, L.