PAVEMENT DETECTOR AND VERTICAL AXIAL SHIFT DETECTOR OF ON BOARD RADAR

A road surface detection apparatus capable of detecting an upward/downward displacement in radar axis when detecting a road surface by projecting a radar beam. The apparatus projects a radar beam signal onto the road surface on which the radar-equipped vehicle is traveling, and receives a signal containing a reflected signal of the radar beam signal. Then, the apparatus compares the level of the road surface reflected signal contained in the received signal with a predetermined reference level and, if the result of the comparison lies outside a predefined range, then the apparatus determines that the axis defining the projection direction of the radar beam signal is displaced.