Monostatic RCS hot-spot modelling of large grooved structures

The monostatic radar cross section (RCS) hot-spot characteristics of electrically large grooved structures were analyzed. The structures' monostatic RCS and inverse synthetic aperture radar (ISAR) image properties [1] at X-band were characterized for the far-field. These structures were assumed to have perfect electric conductor (PEC) properties. It is anticipated that the study of these simple structures, from a 2D analysis approach [2], could yield good insights into the RCS and ISAR characteristics of electrically large and complex tubular structures (e.g. intake cavities of jet engines) [3] at microwave frequencies. In the modelling, computer aided design (CAD) models of these structures were created and meshed. They were then utilized as inputs into an RCS computer code called RAPPORT [4]. Since this code was implemented using the ray-tracing technique based on physical optics (PO), it employs a parameter which allows the user to define the maximum number of “physical optics reflections” (PO reflections), also called specular reflections, off the meshed surfaces in a single ray traced. However, diffraction and polarization effects were not emphasized in this study due to limitations in RAPPORT.