Abstract
An early warning system for sensing suspicious ships approaching nuclear power plants and other important facilities located at the coast is necessary. Thus, the authors developed a buoy equipped with a marine surveillance system.
In this paper, the results of actual sea trials of the prototype buoys for a two-month period from July to August in 2008 and 2009 are presented. The underwater sound recorded with hydrophones mounted on the buoy was analyzed, and the method used to detect underwater sound of ships approaching the buoys was evaluated. Next, the underwater sound from the experiment boat rotating around the buoys was observed and analyzed in order to build an algorithm for predicting the geometric direction and position of the boat’s underwater sound source. Results show that this technique can be one of the methods for real-time underwater sound monitoring. The authors expect that this surveillance buoy system will be useful in predicting the presence of dubious ships or poaching boats by sensing underwater sound.
