Method and Apparatus for Generating Optical Duobinary Signals with Enhanced Receiver Sensitivity and Spectral Efficiency

A method comprising:

• generating two complementary binary data streams;
• delaying one of the complementary binary data streams;
• modulating an optical duobinary signal using the undelayed complementary binary data stream and the delayed complementary binary data stream;
• filtering the optical duobinary signal;
• and
• transmitting the filtered optical duobinary signal is transmitted to a receiver.

A transmission system comprising:

• a source configured to generate two complementary binary data streams;
• a fractional-bit delay module in communication with the source and configured to delay one of the complementary binary data streams;
• a modulation module in communication with the source and the fractional-bit delay module and configured to convert the undelayed complementary binary data streams and the delayed complementary binary data streams into a fractional-bit delayed optical duobinary signal;
• and
• a band-limiting node in communication with the modulation module and configured to filter and transmit the optical duobinary signal.