Fundamental second-order nonlinear distortions in analog AM CATV transport systems based on single frequency semiconductor lasers

The author analyzes the fundamental second-order nonlinearities and their composite distortions in lightwave analog AM CATV transport systems based on single frequency semiconductor lasers. The nonlinear interaction between the photons and the electrons in the laser, the nonlinear dynamics of laser spatial hole burning, and the nonlinear interaction of fiber chromatic dispersion and laser frequency chirping are strongly dependent on the CATV carrier frequencies. The author found that the overall distortions increase for higher carrier frequencies and longer fiber spans. The distortion levels, however, are within the critical requirements for current and future CATV transport systems.>