A pilot study of the advantage of radar image data over ARPA based position and bearing

Abstract

In this paper, we analyze the added value of maritime radar image data for tracking and classification of target vessels. The current automatic radar plotting aid (ARPA) only provides a single point of the acquired radar target. A radar image on the other hand contains two dimensional information on the whole surrounding area as well as the 2D projection of the target itself. The paper starts with a theoretical discussion of possible additional values of using radar image data instead of ARPA based distance and bearing information. In addition, an astrophysical tool is used to extract targets and estimate their minor and major semi-axes of the best fitting ellipse. Finally, we analyze the stability of the ellipsoidal parameters during the tracking of targets. This is done using the Automatic Identification System (AIS) as the primary source of target vessel positioning. With the AIS data it is possible to choose the closest ellipse on the radar image. Repeating this procedure until the AIS target leaves the radar range makes the stability analysis possible.