Precise 3-D Object Position Tracking using FMCW Radar

This paper presents a FMCW radar system for high precision three-dimensional object position tracking. Theoretical analyses of the 3-D triangulation concept and the accuracy limits are given. Three 2.45 GHz radar modules measure the distance from different spatial locations to an active reflector unit installed on the object to be localised. By modulating the radar signal in the active reflector unit, disturbing echoes and clutter noise are suppressed. An advanced signal processing concept evaluates the difference of frequency and phase terms of two adjacent modulation components. Test measurements demonstrate a 3-D position measurement with submillimetre precision. This performance makes the new approach suitable for a wide range of applications in robotics, industrial automation and in the medical area.