Gating for target tracking among islands and fjords

Established target tracking theory assumes that there are no obstacles, allowing the targets to follow a motion model (such as the constant velocity model). While working fine in the open sea, this assumption can lead to wrong associations in coastal waters. We propose three different gating algorithms for use in coastal areas. The methods are based on anisotropic fast marching, breadth-first search on a regular lattice and Dijkstra's algorithm on a variable-resolution graph. The proposed methods have shown to give better association results than the circular gattng method.