Abstract

Direct 40 Gb/s electrical modulation as in electrical time division multiplex (ETDM) has advantages over optical time division multiplex (OTDM) with respect to the mechanical size, cost and volume production for 40 Gb/s transmission system. The progress of 40 Gb/s component technologies, especially in the electrical multiplexer/demultiplexer and the electro-optic modulator (EOM), has made the development to deployment of 40 Gb/s ETDM transmission system within reach. In the choice of EOM, electroabsorption modulator (EAM) has the advantage over LiNbO₃ modulator (LNM), on its small size, compatibility to integrate with DFB lasers, low driving voltage, and bias-drift insensitivity. To our knowledge, whereas there are a number of publications on EAM design,^1–3 there are few publications on EAM modeling and the application of such a model on the design optimization. In this paper, a large signal model for EAM is presented on the insertion loss (IL) and extinction ratio (ER) prediction with respect to different bias and RF driving signal levels. A figure of merit (FOM) for EAM is proposed to compare EAM performances. Furthermore, two system performance parameters are introduced to evaluate EAM IL and ER on end-to-end system performance.

© 2002 Optical Society of America