Study of Optical Channel Fault Monitoring Systems Based on Fabry-Perot Laser Diodes

• Main Authors: Tzu-Young Chou, 周子揚
• Other Authors: Chun-Liang Yang
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/dq2xs3

碩士 === 淡江大學 === 電機工程學系碩士班 === 102 === Passive optical networks (PONs) nowadays become significant architectures of access networks. As a low-cost and wideband network scheme, PONs are composed of passive components in the networks, but only optical line terminal (OLT) and optical network unit(ONU) are active apparatuses. So they not only provide a service with high quality and wideband, but also avoid many problems on the maintenance and construction in the networks. However, these characteristics of PONs also make defect. It is easy to affect the performance of the network transmission system by the branching structure on fiber or the quality of central office transmission equipment. For operators, to achieve PON systems, it is important to monitor in real-time and to have a protective scheme. Similarly, for a wavelength-division-multiplexed PON (WDM-PON) system carrying high-capacity data to many users, channel fault monitoring is essential for ensuring the system reliability.Tunable optical time-domain reflectometers can be used to detect fiber breaks in both the feeder and distribution fibers. An amplified spontaneous emission source or other multi-wavelength light sources can also be used to provide the monitoring signal for channel fault monitoring in a WDM-PON system. In addition, a fiber Bragg grating or a mirror can be designed in the ONU to carry out the channel fault monitoring. In this thesis, the proposed optical monitoring unit based on a single low-cost coaxial-type FP-LD as a dithered reflector and a photo-receiver has been demonstrated in a simple WDM-PON architecture. It is very suitable for monitoring the status of fiber paths and ONUs.