A new algorithm to calculate the reference image of ship targets for ATR using ISAR

This paper develops a new algorithm to calculate the reference inverse synthetic aperture radar (ISAR) images of candidate targets for ship target recognition. To make reference images, cross range aids defined by the target's unknown angle velocity vector must be estimated for projection of reflectivity on the candidate targets to the range-Doppler plane. To estimate cross range axis, we extract the centerline and the Doppler width of the ship target from the observed ISAR image. By using these information and the relation between the direction vector of the straight line in the space and the ISAR image formulated in this paper, the cross range vector can be estimated for each candidate target. The effectiveness of the proposed algorithm is evaluated by using simulated targets.