Polarimetric Co-location Layering

Organization: MIT Lincoln Laboratory
Year: 2017

Polarimetric Co-location Layering (PCL) is a novel algorithm that leverages polarimetry in maritime radar to mitigate the high false-alarm rate caused by radar returns from the sea surface. Detection and tracking are key components of the radar signal processing chain that enable all functions of maritime radars. In geometries in which these radars look at near-horizontal incidence (low grazing angles) out to sea, radar returns from the sea surface (sea clutter) can look object-like and can persist for several seconds. Consequently, the false-alarm rate of the standard constant false-alarm rate (CFAR) detection process can rise dramatically. False alarms can then inundate a radar’s tracker, rendering the tracker unable to form tracks on objects of interest. These consequences worsen as the grazing angle becomes lower, and pose significant challenges for all maritime radar platforms whether they are airborne, land-based or sea-based. The PCL algorithm solves the low-grazing-angle sea clutter problem in a robust and practical fashion. PCL reduces the false-alarm rate of CFAR detection by an average of two orders of magnitude, enabling rejection of false alarms and detection of manmade objects even in high sea clutter states.