Inverse Synthetic Aperture Radar Imaging With MATLAB Algorithms, 2nd Edition

12Some Imaging Applications Based on SAR/ISAR

In this chapter, some of the imaging applications based on synthetic aperture radar (SAR)/inverse synthetic aperture radar (ISAR) imaging methodology are covered. As the conventional SAR/ISAR imaging algorithm is based on the assumption that the transmitter and the receiver are situated at the far field of the target, we will present that there are applications in which SAR/ISAR imaging principles can be used to construct the radar images for the cases the transmitter or both the transmitter and the receiver are at the near‐field of the target.

One of the challenging and popular near‐field radar imaging problems is so‐called ground penetrating radar (GPR) that is based on the electromagnetic (EM) scattering from subsurface objects or discontinuities. GPR imaging concept and its associated applications are quite diversified ranging from detecting unexploded ordinances to finding water leakages. Therefore, the applied techniques in GPR also vary according to the application. A more detailed review of the GPR algorithms can be found in references (Daniels 1996; Özdemir 2011; Özdemir et al. 2014) and fall out of the scope of this book. Instead, we shall demonstrate that SAR imaging algorithms that were briefly given in Chapter 3 can also be applied to the GPR imaging problem and have the potential of providing well‐focused images of sub‐surface objects.

Another interesting and useful near‐field radar imaging application is so‐called ...