Field Experiments for Ship Detection Using SAR and Its Applications for Korea Coast Guard

Abstract

With continuous increment for demand towards the maritime safety and security, vessel surveillance is suitable way to reduce the effort in vessel identification near to the coast and in Ocean. This paper presents the combined use of dual sensor system data like SAR and AIS for the purpose to identify the different types of ship presents in the ocean. Ship traffic monitoring may be carried out with the combined use of SAR and AIS data. SAR data is useful to provide wide information about the area and signatures of vessels along with land and ocean during day or night time with independent of cloud conditions and AIS data provides the information related to the ship parameters like positions, types, Maritime mobile service information (MMSI) etc. An operational system should combine satellite SAR report with the AIS reports for the traffic monitoring. Ship detection may be carried out by means of the SAR data with number of brighter pixels presents in the ocean and the Ship information can be obtained from the chain of AIS receiver presents near to the coast and ship identity information we can get from the port authority. Our main aim is to combine the satellite based information as well as the ground based information for identification. SAR provides the wide coverage with good resolution imagery, so the detection of small ships are also possible due to aerial view. SAR data gives the information related to intensity or amplitude of the backscattered signals which returns from the ground with useful information regarding ship and other structure signatures in imagery. The detection by SAR is limited due to the sea-clutter presents in the ocean and it increases the effort for ship detection. Sea-clutter produces the unwanted false alarm and is recorded by SAR sensors and so in order to remove the sea-clutter information from SAR imagery we need to go for the constant false alarm techniques with a particular threshold value in order to get the information related to t