Flat-topped chirp induced by optical filter edge

A fiber optic communication system comprising:

• an optical signal source adapted to produce a binary amplitude modulated signal having a first adiabatic instantaneous frequency profile;
• and
• an optical spectrum reshaper adapted to receive the signal and change the first adiabatic instantaneous frequency profile to a second substantially flat-topped instantaneous frequency profile;
• wherein the optical spectrum reshaper is characterized by a slope of its optical transmission versus optical frequency profile;
• and
• wherein the slope of said OSR is selected according to the approximation
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• πτ
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• 0
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A fiber optic communication system comprising:

• an optical signal source adapted to produce a binary amplitude modulated signal having a first adiabatic instantaneous frequency profile;
• and
• an optical spectrum reshaper adapted to receive the signal and change the first adiabatic instantaneous frequency profile to a second substantially flat-topped instantaneous frequency profile;
• wherein the optical spectrum reshaper is characterized by a slope of its optical transmission versus optical frequency profile;
• and
• wherein said slope is between 2 dB/GHz and 4 dB/GHz, and the bit rate of the binary amplitude modulated signal is about 10 Gb/sec.

A fiber optic communication system comprising:

• an optical signal source adapted to receive a base signal and produce an amplitude modulated first signal having a first adiabatic instantaneous frequency profile;
• and
• an OSR adapted to convert said first signal to a second signal, wherein said second signal has a substantially flat-topped instantaneous frequency profile;
• wherein said base signal is a non-return-to-zero (NRZ) signal;
• and
• wherein the product of the flat-topped instantaneous frequency excursion and 0 bit duration of the instantaneous frequency of said second signal is between an odd integer multiple of a fraction between 0.25 and 0.75.