Detection and tracking of non-cooperative vessels

Harbor areas and high-traffic shipping lanes near coasts are specific causes of high risk because at these regions a high number of vessels of various sizes are concentrated within a limited space. The persistent surveillance (24 hours / 7 days) of the sea surface is hampered by the occurrence of small vessels, falling below the requirement to carry automatic identification systems (AIS). Non-cooperative objects, ranging from vessels with defect AIS-transponders to smugglers and potential terroristic attacks, complete the scenario, resulting in missing, wrong, or spoofed positions and ID signals. In addition to automatic identification systems used for larger and cooperative vessels, active and passive radar systems and optical sensors should be considered. Especially harbor areas and shipping lanes of limited spatial extent are well suited for the supplementary surveillance by means of radar and optical systems, as these scenarios allow for the necessary permanent installation of sensor equipment. The Fraunhofer IOSB has long-term experience regarding the automatic surveillance of the sea surface based on optronic sensors, especially IR sensors. In the course of these studies, several measurement campaigns at various climatic regions have already been conducted, using different active and passive optronic sensors, cooled as well as uncooled, and operating at various spectral bands. The captured scenarios cover mainly asymmetric threats, e.g. small boats and swimmers, for which suitable detection, tracking and classification algorithms have been successfully developed. The Fraunhofer FKIE has long-term experience regarding fusion of data from heterogeneous sensors and information sources such as Automatic Identification System (AIS), Vessel Traffic Services (VTS), maritime & coastal radar (active and passive), Long Range Identification and Tracking Systems (LRIT), Satellite based AIS (Sat-AIS), Satellite based Earth Observation, Airborne Remote Sensing, emitter localization (DoA, TDoA, FDoA). Combining AIS, radar, and optical sensor systems in an integrated security concept especially for ports and regional maritime security systems allows for several new scenarios: cooperative vessels can be tracked and guided; non-cooperative vessels can be detected as such -DDS concerning the mere AIS transponder behavior -DDS and further inspected by optical systems and suitable vision algorithms. But even the inverse problem can be tackled: vessels detected and tracked within the images from optical sensors can be rechecked for matching AIS transponder signals. In such a way, defect AIS transponders and wrong or spoofed AIS signal can be detected.