Abstract: A RADAR system and associated methods are used to detect obstacles obscured from view when backing a trailer. An autonomous tractor is equipped with a rear facing RADAR device that has a field-of-view under the trailer and is configured to output RADAR returns from reflections. A controller of the tractor classifies RADAR returns from the RADAR device according to a number of reflections by a dock wall and a trailer face (e.g., a back end of the trailer) of a corresponding RADAR beam. The RADAR returns are correlated based on distance, and distance of a RADAR return from an obstacle is corrected based on the number of reflections. Advantageously, by processing RADAR returns from both direct and reflected RADAR beams, the controller is able to detect obstacles hidden behind the trailer and flag the obstacles as a hazard.