System and method for detecting optical fiber faults of passive optical network

Abstract

The invention provides a system and a method for detecting optical fiber faults of a passive optical network. The method comprises the following steps: optical time domain reflectometry (OTDR) equipment gives a command aiming at the detection of a certain branch of optical fiber; a branch optical fiber selector communicates the optical path of the branch optical fiber specified by the command after receiving the command; the OTDR equipment analyzes whether an emitting signal is abnormal or not to confirm whether the backbone optical fiber or the corresponding branch optical fiber has faults or not according to a reflected signal corresponding to the received optical distance detection signal after the optical distance detection signal is emitted; in the invention, the trunk and all the branches of optical fiber in the passive optical network can be monitored, detected and positioned, and the branch optical fiber corresponding to an OTDR monitoring signal is selected to detect by selecting the OTDR monitoring signal so that the problems of signal overlap and difficult division of the branch optical fibers with the same length can be avoided.

Description

technical field [0001] The invention relates to an optical network system in the field of communication, in particular to a system and a method for detecting a failure of an optical fiber in a passive optical network. Background technique [0002] The rapid development of network technology and the popularization of network applications, such as network communication, network shopping, and network entertainment, have become part of modern people's life, so the existing access network copper wire (wired) system is far from meeting this requirement. A high-speed and broadband demand, and the passive optical network is broadband and high-speed, environmental protection and energy-saving broadband access technology, is the best candidate to replace the existing access network, it is being accepted by most operators And be deployed to meet the growing communication users and faster and better service needs. [0003] Passive Optical Network (PON) is a point-to-multipoint optical ...

AI Technical Summary

Problems solved by technology

[0006] 1. If the distance from part of the branch fiber to the optical splitter is approximately equal, the OTDR cannot tell which branch fiber signal it is, unless a high-resolution OTDR is used

but the highest resolution available now is 2 meters

[0007] 2. If the splitting ratio of the optical splitter is very large, the Rayleigh reflection signal of the branch fiber will have a large loss when passing through the optical splitter. When it reaches the detector of the OTDR, the signal has been submerged in the noise

What's worse is that for ODN with a large splitting ratio (such as: above 1:128 splitting ratio), the gain brought by the filter may not be enough for the loss of the splitter, so the OTDR equipment at the local office may not be able to receive to any information from the branch fiber

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