Abstract

Recent demonstrations of lightwave systems operating at bit rates as high as 16 Gbit/s (Ref. 1) and over optical amplifier based spans hundreds of kilometers long² have renewed interest in evaluating polarization-mode dispersion as a potential limitation in high bit rate systems. For such applications it is important to consider random polarization-mode coupling caused by internally or externally derived perturbations on the fiber birefringence. One consequence of such mode coupling is that the temporal response of a birefringent fiber can be altered by changes in ambient temperature owing to the sensitivity of mode coupling to the relative phase of the modes at a given perturbation in the fiber.³ We show that, because of such sensitivity to the environment, polarization-mode dispersion can lead to fading of the baseband signal in high-bit-rate lightwave systems in many ways analogous to multipath fading in radio systems. Such fading affects both coherent and direct detection systems.

© 1990 Optical Society of America