Subsea cable condition monitoring with distributed optical fiber vibration sensor

A novel subsea cable condition monitoring technique based on embedded optical fiber inside the cable is demonstrated. It is shown that a distributed optical fiber vibration sensor can be used to map dynamic strains all along the cable simultaneously. It is experimentally shown that such system can fully quantify the location and strain level at each point on the cable as a function of time for both abrupt impact and cyclical loading. The sensing system demonstrated a spatial and strain resolution of 1 m and 4 μ, respectively, over a 10-km sensing range.