ISAR geometry, signal model, and image processing algorithms

Inverse synthetic aperture radar (ISAR) technique provides high-resolution images of observed moving objects. However, shadow-occluded effects and noise, which results in lack of fractions of the object geometry, often corrupt ISAR images. To facilitate the image analysis and to solve the target identification problem in most practical applications additional image-processing procedures are strongly required. The aim of the present research is based on ISAR geometry and signal modelling to develop procedures improving quality of images and extract the silhouette contour line of the ISAR image, the main geometric parameter in the target recognition process. The problem is solved in two main stages. First, ISAR geometric parameters are described and expressions for linear frequency modulated signal modelling and imaging are derived. Second, image-processing algorithms for ISAR image improving and contour line extraction are developed. All stages of image-processing and reconstructing algorithms are illustrated by results of numerical experiments.