Low ground clearance vehicles (LGCV) getting stuck at tracks of highway-rail grade crossings (HRGC) poses a severe safety risk. Vehicles with long wheelbases and low ground clearance are more likely to encounter this on high-profile HRGCs. There are currently no commercial automated systems to detect and compute minimum clearance, and suspended or protruding rigid parts of LGCVs, and provide advance warning before reaching HRGCs. To address this, IAI and its collaborator, Sabra, Wang & Associates, have been awarded a contract entitled, “Advance Radar Based Low Ground Clearance Vehicle Detection and Warning System. An innovative, inexpensive, stand-alone, lane specific and vehicle specific LGCV detection and warning system will be built. First, vehicles with longer wheelbases will be detected and prescreened using a pair of inductive loops or magnetometers with a high resolution interface card. Next, a millimeter wave imaging radar downstream will be triggered to capture a high resolution profile of the vehicle and to calculate the lowest clearance to the pavement. IAI’s proprietary Scan Synthetic Aperture Radar (ScanSAR) algorithm will be used to perform 3D imaging of vehicle’s underbody profiles. The real-time ScanSAR algorithm will be implemented on IAI’s Multi-Channel Digital Signal Processing (MCDSP) system. This system supports multi-mode warning, with the ability to support both “infrastructure” and futuristic “onboard” warning systems. The system will work for all high-profile HRGCs and vehicles of various wheelbases and underbody clearance, and supports multiple lane operations at highway speeds. The proposed system has very fast processing and response time, and can function in all weather, visibility and road conditions.