Dispersion Monitoring In WDM Networks Based On Silicon Optical Waveguides And Micro-ring

Dispersion monitoring is a key technique of realizing high-speed optical communication. The structure being an all-optical system can be integrated on a chip when using the nonlinear effects of silicon optical waveguides to monitor dispersion. Silicon optical waveguides have notable nonlinearity. When the signal and probe light go through the silicon optical waveguide after combining, the silicon optical waveguide takes on high nonlinear effects, such as self-phase modulation (SPM), cross-phase modulation (XPM) and four-wave mixing (FWM), which will vary in the different residue dispersions of the link.The silicon optical waveguide is modeled using Matlab and the dispersion monitoring system is established based on the waveguide after validate it. Via effectively setting the central frequency and bandwidth of the filters, the different spectrum changes related to SPM, XPM and FWM can be detected simultaneously, in order to monitor the link dispersion. As we know, two-photon absorption (TPA) and free carrier effects in silicon waveguides will result in not only attenuation, but also spectrum distortion. TPA will cause spectrum narrowing, while free-carrier dispersion (FCD) will cause blue shift in spectrum. However, these effects can be ignored when the input signal power is low enough. Finally, the monitoring dispersion range can be±40ps/nm for max in this scheme. The research turns out this technique can be used to monitor the residue dispersion of the link on the chip level.Micro-ring structure of silicon waveguide will further enhance nonlinear effects in resonant frequency. Application of micro-ring devices will effectively improve the miniaturization of monitoring system...