Simulation of the passive recirculating fiber loop buffer

The current trends within ultra high-speed optical time division multiplexed (OTDM) based communication systems dictate the increasing need for all optical buffering systems. Such systems inherently avoid the bottlenecks associated with opto-electrical (O/E) and electro-optical conversions (E/O)1. These buffers would enable the storage of data for discrete time intervals, and are necessary for many OTDM applications. Storage time limitations within passive recirculating fiber loop buffers are mainly due to the dispersive, nonlinear and loss properties of the fiber. These result in both amplitude decay and pulse spreading which may have a detrimental effect on data integrity. In this paper, we examine the propagation of both standard soliton and Gaussian-soliton shaped pulses within a recirculating fiber loop buffer. The simulation model is based on the nonlinear Schrodinger equation (NLSE) and accounts for fiber loss within the communications channel. At this stage pulse interactions are not considered and direct modulation of the launched pulses is assumed. Simulation results for bit error rate performance at different buffer loop numbers is presented.