Advanced range sensor processing using DGPS and a geospatial database

Manufacturers of automotive radar typically use narrow beam angles to minimize the number of detected objects (traffic signs, guard rails, etc.) which ought not to pose a threat to the host vehicle. Although narrow beam angles are sufficient for some applications, namely automatic cruise control (ACC), wider fields of view are necessary for driver assistive systems. In order to make wide field of view range sensors perform well for driver assistive systems, a novel radar processing technique has been developed which integrates vehicle location provided by a high accuracy Differential Global Positioning System receiver and a highly detailed Geospatial Database map into the radar processing algorithm. Road objects such as road shoulders and road islands are used to delineate the driveable road surface. Objects detected by the range sensor which are located off of the driveable road surface are identified as such. Relevant vehicle systems (i.e., Heads Up Display or Collision Avoidance) can use this information to minimize false positives. This radar processor was implemented on an International snowplow and results from a series of experiments using this vehicle on Minnesota Trunk Highway 101 between Rogers and Elk River are presented. The system proved very effective at minimizing radar false positives.