Noisy OTDR Data Event Detection Analysis for the Real Time Optical Fiber Link Monitoring

Abstract This paper, proposes a new analysis method for the event detection of an OTDR signal. An OTDR signalwas passed through the Hamming filter to remove the high frequency noise included in the signal. The signal wasthen passed consecutively through a differential filter to detect the events of interest. The terminal position was determined using the fact that there is a large gap between the signal and the trailing noise power beyond the terminal.This study examined the local maxima of the signal up to the terminal position and determined the peak regions.The real events were determined from the peak regions using noise information and peak threshold. Finally, the userevents were found by inspecting the user peaks beyond the terminal position. The events of the OTDR signal withoutusers are located at less than 17m compared to the optical fiber link setup. The events of the JDSU device are locatedless than 25m and their users are less than 5m. For the RadianTech device, the events are detected at less than 19mand the users are found in 5m. The results suggest that the proposed method is sufficiently applicable to an opticalfiber link monitoring system.