Prof. Marco Martorella
Department of Information Engineering
University of Pisa, Italy
Dr. Brian Rigling
Department of Electrical Engineering
Wright State University, USA
SAR/ISAR images have been largely used for earth observation, surveillance, classification and recognition of targets of interest. The effectiveness of such systems may be limited by a number of factors, such as poor resolution, shadowing effects, interference, etc. Moreover, both SAR and ISAR images are to be considered as two-dimensional maps of the real three-dimensional object. Therefore, a single sensor may produce only a two-dimensional image where its image projection plane (IPP) is defined by the system-target geometry. Such a mapping typically creates a problem for the image interpretation, as the target image is only a projection of it onto a plane. In addition to this, monostatic SAR/ISAR imaging systems are typically quite vulnerable to intentional jammers as the sensor can be easily detected and located by an electronic counter-measure (ECM) system. Bistatic SAR/ISAR systems can overcome such a problem as the receiver can act covertly due to the fact that it is not easily detectable by an ECM system, whereas multistatic SAR/ISAR may push forward the system limits both in terms of resolution and image interpretation and add to the system resilience. In this tutorial, elements of bistatic SAR and ISAR will be introduced in terms of system geometry, signal modeling, image reconstruction and interpretation. Bistatic scattering phenomenology will be explored through simulated examples. Applications of bistatic SAR and ISAR will also be illustrated, such as measured and emulated bistatic ISAR and passive ISAR. Multistatic radar imaging will also be introduced in terms of theoretical and conceptual aspects before presenting its applications, which will cover 3D radar imaging, challenges to multistatic visualization, imaging of non-cooperative targets immersed in clutter, multi-perspective radar imaging of moving targets, and so on.