Hybrid strategy to simulate millimeter-wave RADAR devices for automotive ADAS

A multiscale hybrid strategy is proposed to simulate Advanced Driver Assistance Systems (ADAS) in both Short Radar Range (SRR) and Long Radar Range (LRR). The first development stage was focusing on small sized radar arrays operating at 24 GHz and located onboard automotive vehicles, behind plastic bumpers with very thin metalized paint coatings. With the objective of managing the full 3D scene, additional hybrid features were proposed to take into account all major contributors like the roadway, rail guards and other nearby vehicles. This result could be achieved by combining a preliminary characterization of the emitting device with a Physical Optics (PO) computation of the related electromagnetic environment. The same strategy was then applied to extend this solution to anti-collision, pre-crash and other Adaptive Cruise Control (ACC) systems dealing with long range detection through millimeter-wave devices operating at 77 GHz. Two different options were proposed for the coupling process, dealing either with near radiated fields along Huygens surfaces surrounding the emitting source or relying on the Spherical Wave Expansion (SWE) technique, much faster with realistic full size models. Dedicated PO upgrades also appeared to be necessary to handle the plastic structure of the front bumper, the emblem location and the grille. Typical 24 and 77 GHz applications are presented in both cases, short and long range.