Capacity limits of information transmission in optically-routed fiber networks

Optical networks are the backbone of our information society, and the single-mode optical fiber is its transmission medium. The "fiber channel" differs in many ways from other commonly encountered communication channels such as wireless and satellite channels. The most crucial difference is the presence of a nonlinear phenomenon in the fiber, the optical Kerr effect. Optimally managing the Kerr nonlinearity is currently viewed as central to determining the capacity limit of modern optically-routed networks. We present here a conservative estimate of the fiber channel capacity using reverse signal propagation in a band limited optical path of an opticallyrouted network. This study fully accounts for all instantaneous fiber Kerr nonlinearity's effects on both signal and noise. We predict capacity per unit of bandwidth (or spectral efficiency) well above current record experimental demonstrations.