Automatic line protection testing: SDH equipment with optical fibre amplifier systems

The most critical goal to be reached when designing long distance networks is the capability to transport high capacity signals with a limited number of repeaters. This can be accomplished by the combination of Synchronous Digital Hierarchy (SDH) technology and Optical Fibre Amplifiers (OFA). Due to the very high power levels involved in this systems, a protection method to ensure human safety in case of cable break is required; IU-T G.958 Recommendation gives an automatic shut-down procedure for SDH systems. In this paper, a shut-down time measurement methodology is proposed to test the potential compatibility of OFAs with the available SDH systems during the protection mechanism.<
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