Abstract

Since the receiver high sensitivity achieved with an optical preamplifier is close to the theoretical limit, further span increase in repeaterless transmission requires an increase of the postamplifier output power. Postamplifiers with output powers as high as +24.5 dBm have recently been developed.¹ When such optical power is launched in a long fiber span, nonlinear effects, such as self-phase modulation (SPM), can affect the transmission, particularly when combined with high group- velocity dispersion^2-4 (GVD).

© 1994 Optical Society of America