New method analyzing eye patterns and its application to high-speed optical transmission system

An advanced method of analyzing eye patterns is proposed which plots the eye pattern as a function of the error rate. The method is applied to high-speed optical-transmission systems and its usefulness is confirmed. Degradation of eye opening due to noise and intersymbol interference is investigated quantitatively using the 10/sup -10/ BER eye. An automatic gain-control system is evaluated from a viewpoint of eye margin, and a gain control system having an improved eye margin performance is proposed. Low-probability abnormal phenomena, such as turn-on fluctuations and mode partitioning in directly modulated distributed feedback (DFB) lasers, are observed using this method.<
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