UC San Diego

Wavelength Division Multiplexed optical networks serve as the backbone of the telecommunications infrastructure around the world. Presently, the dominant impairment in such systems is the Kerr-induced nonlinear crosstalk, which imposes a fundamental limit to their information-carrying capacity. Until recently, digital signal processing-based approaches used for the compensation of nonlinear crosstalk have had limited success for reasons that have remained unclear. In this dissertation, the frequency stability and mutual coherence of the optical carriers is for the first time proven to play a critical role in Kerr-mediated interactions.

As a solution, optical frequency combs are leveraged to provide a stable frequency reference, enabling the precompensation of nonlinear crosstalk in multichannel systems. Supporting experimental demonstrations indicate that the fiber capacity and system reach can be significantly increased over previously established limits. This dissertation accordingly proposes and validates three different comb-based frequency-referenced transmitter architectures, and finally, an experiment encompassing the developed groundwork is demonstrated to achieve record nonlinearity cancellation in a state-of-the-art high-capacity system.