SeaSentry: Maritime Real-Time Positioning in a Passive Radar-Detector Network

Maritime transport and vessel monitoring rely on multiple systems for positioning, such as the Automatic Identification System, electro-optical systems, and shore-based radar systems, to improve safety and efficiency in vessel tracking. However, each system has inherent limitations, including coverage gaps, reliance on vessel compliance, and limited real-time monitoring capabilities. As a complementary approach to existing methods and systems, this paper presents the SeaSentry system, a passive sensor network designed to detect, position, and track vessels in real time, thus eliminating the need for onboard installations. The sensors detect radar pulses emitted by the vessels' rotating radar antennas and compute time stamps as the radar beams pass over them. Geometric constraints can be derived from time differences of arrival to localize the vessels, with time error and synchronization demands in the millisecond range. Along with some initial results, this paper discusses the SeaSentry setup and data processing pipeline.