Optical system employing near-incoherent processing for distortion correction

A system for providing compensation for optical nonlinearities in an optical system that transmits data signals in a data transfer frequency band, said system comprising:

• an optical source for providing a coherent main optical beam;
• a beam splitter means for receiving said optical beam and providing first and second split optical beams;
• a frequency generator for generating a radio frequency (RF) modulation signal whose frequency spectrum includes said data transfer frequency signal band;
• a RF signal tap means for extracting a reference portion of said RF modulation signal;
• a main modulator means for receiving said RF modulation signal and modulating said first split optical beam to output a modulated main optical beam having modulated and distorted optical components;
• a quasi-incoherent compensation apparatus including;
• a means for generating a synthesized optical beam incoherent with said main optical beam in said data frequency signal band such that no optical interference products between said main and synthesized optical beams occur within said data transfer frequency band when said main and synthesized optical beams are combined;
• a means for generating an error signal indicative of the difference between said RF signal and said distortion portion of said main optical beam;
• a compensation modulator means for receiving said error signal and modulating said second split optical beam to output a modulated compensation optical beam;
• and
• an optical combiner means for receiving said main and compensation optical beams and providing therefrom a compensated output beam.