公开(公告)号：EP0776488A4

公开(公告)日：1998-11-18

申请号：EP96913961

申请日：1996-05-07

Applicant: MOTOROLA INC

Inventor： LEMPKOWSKI ROBERT B ,  GHAEM SANJAR ,  KITCHEN W J

IPC: G01S7/02 ,  G01S13/00 ,  G01S13/32 ,  G01S13/60

CPC classification number: G01S13/003 ,  G01S7/024 ,  G01S13/325 ,  G01S13/60

Abstract: A measurement device (103) and method determines various metrics between a vehicle (101) and a ground surface (105) using a transmitter-antenna (109) for emitting energy including a portion directed down toward the ground surface. A receiving antenna (115) has a portion oriented facing toward the transmitter-antenna for receiving a portion of the emitting energy along a direct path (117), and a portion oriented facing downwardly toward the ground surface for receiving a portion of the emitting energy reflected from the ground surface along a reflected path (113). A decoder provides separate indications of forward (121) and sideward (123) velocity relative to motion of the vehicle along the ground surface. Furthermore, the decoder comprises means for determining vehicle height (125) dependent on a measured difference in path length, vehicle level (127), or front to rear tilt angle, dependent on polarization elliptical ratio changes, and road surface conditions (129) dependent on amplitude and phase changes that occur versus time.