Converting a 3D surface into a set of directional scatterers for high-resolution radar response simulation

It is practical and efficient to simplify targets to point scatterers in radar simulations. With low-resolution radars, the radar cross section (RCS) is a sufficient feature to characterize the scattering properties of a target. However, the RCS totals the target scattering properties to a scalar value for each aspect angle. Thus, a more detailed representation of the target is required with high-resolution radar techniques, such as Inverse Synthetic-Aperture Radar (ISAR). In straightforward simulation scenarios, high-resolution targets have been modeled placing identical point scatterers in the shape of the target, or with a few dominant point scatterers. As extremely simple arrangements, these do not take the self-shadowing into account and are not realistic enough for high demands.

Our radar response simulation studies required a target characterization akin to RCS, which would also function in high-resolution cases and take the self-shadowing and multiple reflections into account. Thus, we propose an approach to converting a 3-dimensional (3D) surface into a set of scatterers with locations, orientations, and directional scattering properties. The method is intended for far field operation, but could be adjusted for use in the near field. It is based on ray tracing which provides the self-shadowing and reflections naturally. In this paper, we present ISAR simulation results employing the proposed method. The constructed scatterer set is scalable for different wavelengths enabling the fast production of realistic simulations including authentic RCS scattering center formation. This paper contributes to enhancing the reality of the simulations, yet keeping them manageable and computationally reasonable.