Development of Technology to Detect Underwater Sounds from Ships for Maritime Surveillance

An early warning system is essential for spotting suspicious or unknown ships approaching important facilities located at the coast. For this reason, we have developed a buoy equipped with a marine surveillance system. In this paper, we focused our attention on a difference value between Fast Fourier transform and linear prediction methods to enable early detection of underwater sounds from an approaching boat and observed and analyzed underwater sounds from several ships. Results showed that this maritime surveillance system is highly effective in monitoring underwater sounds. We expect that the system will be useful in detecting the presence of dubious ships or poaching boats through underwater sound detection.