Investigation On High Capacity And Long Reach Wdm Pon System Design And Its Key Techniques

With the emerging of bandwidth consuming applications, Passive Optical Network (PON) has been adopted worldwide. Wavelength division multiplex passive optical network (WDM PON) is the one of the main candidate solutions for the next generation PON because its support for high bandwidth, wide coverage, multi-services and smooth transition. In this dissertation, we have investigated and implemented the key techniques of high capacity and long reach WDM PON including WDM layer experiment system design, colorless ONU and Rayleigh backscattering noise mitigation. The dissertation expends as follows:1. Design and implement the WDM layer experiment system of N X lOGbps WDM PON with the features including channel-reuse,50GHz channel spacing,10Gb/s/λ,, over40km transmission distance,320Gbps for bi-directional transfer. Test results showed that the system reached the designed target.2. Design and implement a colorless ONU solution to control wavelength setting of tunable lasers through optical power detecting. A wavelength management solution based on detecting and controlling tunable lasers’output power is designed for the WDM layer experiment system to fulfill the colorless property of ONU. Test results confirm that this solution would register each ONU in the correct wavelength channel effectively.3. Design a Rayleigh backscattering (RB) mitigation solution for WDM PON through the combined use modulation and filtering. Based on the theoretical analysis and simulation verification of the distribution of RB’s power and spectrum, the RB mitigation solutions of optical RZ-AMI modulation combined with FBG-based optical band-stop filtering and3PAM RZ-AMI modulation combined with electronic high-pass filtering were designed. Simulation results showed that the designed solution could achieve over5dB receiver sensitivity improvement.