Millimetre-Wave Automotive Radar Advance Path Measurement

Millimetre wave radar sensors are being actively developed for automotive applications including Intelligent Cruise Control (ICC), Collision Warning (CW), and Collision Avoidance (CA). Knowledge of the road geometry is of fundamental importance to these future intelligent automotive systems. The interest in such systems is evidenced by manufacturers now starting to incorporate radars in production luxury vehicles. Determination of the road geometry, day and night, under all weather conditions, is a challenging problem requiring both fundamental research and systems studies.

Current automotive radar systems rely heavily on the use of extrapolating yaw rate data generated within the vehicle to produce a prediction of the path of the road ahead. This use of historical data is only satisfactory if the road trajectory is uniform. Sudden discontinuities in the path, such as bends, cause this method of path prediction to produce significant errors. The ROADAR project has developed algorithms to measure, rather than predict, path trajectory ahead of the host vehicle, based on image processing techniques of the radar return signals. This approach has the benefit of all weather performance and additional high resolution range and velocity data. ROADAR has also quantified the electromagnetic mechanisms responsible for radar reflection at 76 GHz by measuring the complex dielectric constant of samples a variety of different road surfaces and roadside furniture targets.