Under the sponsorship of the Air Force Research Laboratory (AFRL), TSC has developed a software tool for studying signature effects caused by target component motion. The Non-Rigid Body Signature (NRBS) code is a physics-based radar signature modeling tool designed for both static and dynamic environments. It can be run on both Windows and Linux operating systems, in single and multi-processor platforms, as well as clustered computer environments.
NRBS is a time domain code that models time-varying physical structures and general waveforms in a straightforward and natural way. It includes a general high-fidelity representation of the incident waveform with linear and nonlinear frequency modulation and user-specified complex pulse envelopes. It also includes a signal processing module that produces pulse compressed range profiles for wide bandwidth linear frequency modulation (LFM) and stepped frequency waveforms. The software features an intuitive graphical user interface and uses facet models in a standard format.
There are many potential sources of target motion that can affect radar signatures; examples include helicopter rotors, vibrating engines, and ground vehicle motion over rough terrain. Below is an example of radar returns simulated by the NRBS software, illustrating the motion-related effects of a dual-rotor helicopter at X-band with 1 GHz LFM bandwidth.
NRBS has been used for studying the RCS variation of ground vehicles due to motion over rough terrain. The following video simulation sequence shows the RCS of a ground vehicle moving over rough terrain, as observed by an X-band radar flying overhead. The ground vehicle was simulated using a faceted computer aided design (CAD) model obtained from a publically-available commercial web site.
For more information please download the Time Domain Signature Prediction Fact Sheet (PDF)