Simultaneous Diagnosis Of Fiber Fault In TDN-PON Using Traffic Signals And Correlation Detection

High optical transmission rate,large transmission capacity and so on,with these advantages fiber has been the main research content of all works of life,the most used is the field of optical communication.As a result,fiber fault detection in optical access networks is becoming more and more important.So far,the expensive Optical time domain reflectometer(OTDR)has always been the primary tool of the fiber fault diagnosis.However,due to the theoretical limitations the conventional OTDR technique cannot be applied to much more complex optical network,but only to point-to-point fiber link.This project propose a cost-effetive method that be able to real-time measure and locate fiber faults in TDM-PON.The cross-correlation trace of the signals in the optical network and their backward Rayleigh scattering lights exhibits a characteristic "function-like".The level and location of the peaks of the cross-correlation trace carry the information about the fiber faults.By usingCommunication signals themselves as reference and detecting lights and correlation-detection technique,this low-cost method enable us to real-time diagnose and locate the fiber faults of TDM-PON with high spatial resolution and high dynamic range.Detail work contents are summarized below:1)We introduce the basic structure of optical access network,and analyze the active optical network and passive optical network.2)We introduce the existing fault detection technology in the TDM-PON,and on this basis,we put forward the method: use communication signals themselves as reference and detecting lights to diagnose and locate the fiber faults of TDM-PON.3)We did the experiment in TDM-PON,the experiment results us the feasibility and the rationality of the method.Besides,we solved the problem: if there were problem on the same length of the optical fiber in TDM-POM,we can also locate it accurately.