Characterization and classification of sonar targets using ellipsoid features

We present a geometry-inspired characterization of target response for active sonar that exploits similarity between intra-class features to distinguish between different targets against environmental objects such as a rock. Key innovation is to represent feature manifolds as a set of ellipsoids, each of which geometrically encompasses a unique physical characteristic of the target´s response. We have demonstrated over experimental field data that for a given target class, these feature ellipsoids exhibit significant clustering behavior that may be exploited to distinguish the target against other distinct target classes or non-targets that commonly contribute to environmental clutter.