The vehicle positioning system consists of the electromagnetic markers buried in roadways and vehicle positioning units mounted on vehicles. It detects lateral differences with the vehicle and the markers for automated cruise-assisted lane-keeping or lane-tracking. In this system, the marker is composed of oscillation circuit without a battery, and it can only respond to the electromagnetic wave of the resonance frequency. The vehicle positioning unit irradiates the electromagnetic wave of the specific frequency toward the marker. The resonance echo signals from the marker are received by three antennas, and the unit detects the lateral difference from the intensity of each echo signals. For automated cruise-assisted lane-keeping or lane-tracking, this system would be promising at three following points. The detection error of lateral distance was within 5cm. The unit could be set in the bumper at the 50cm height from the ground. The system was not affected even if the marker was at 10cm depth of water. (A*)
Abstract