The proposed research is to investigate the transmission impairment of optical fibers for AM/QAM CATV systems due to fiber nonlinearities. The PI proposes to investigate the following topics: (1) SBS suppression techniques; (2) modulation instability in single-channel links; (3) use of dispersion management for reducing the impact of nonlinearity, (4) cancellation techniques for reducing SRS and XPM crosstalks; and (5) optical carrier suppression. The work also involves industrial collaboration with Harmonic Lightwaves.