Demultiplexador óptico temporal baseado em anel óptico não linear.

Abstract

Optical networks are high-speed networks, comprised of photonics devices, capable of performing traffic routing, multiplexing and restoration, both at wavelength and service level. An optical network provides a common infrastructure over which a variety of services can be delivered. Its importance is due, primarily, to the removal of the well-known “electronic bottleneck”. The enormous capacities made possible by the use of optical networks are crucial for the continuous development of applications requiring ever increasing bandwidths. The research efforts now being carried out in the field of optical networks aim at “transparent networks” (all optical networks), for which several photonics components are important. Among them are the “all optical demultiplexers”, the main subject of this Dissertation. Digital simulation is commonly used as a tool for designing and performance analysis of optical networks. The main objective of the work reported herein was to design and implement an optical demultiplexing section to extract channel(s) of an optical time division multiplexing (OTDM) signal. A model of an optical time division demultiplexer based on a nonlinear optical loop mirror (NOLM) has been implemented using the VPItransmissionMaker environment. To introduce the necessary nonlinearity in the optical loop, a semiconductor optical amplifier (SOA) has been used. The simulated model is totally optical, therefore suitable as an element of an all-optical network. The model obtained has been tested under several operational conditions, among them: (i) varying optical frequency difference between the multiplexed signal and the control signal; (ii) different optical pulses duration; (iii) different coupling ratios for the optical coupler at the input of the loop, and (iv) different peak powers for the pulses comprising the input multiplexed signal. For each case the bit error rate (BER) of a chosen recovered channel has been evaluated. Numerical results of the BER are presented.