Abstract: A process for monitoring traffic for automatic vehicle incident detection using radar waves to detect the vehicles, their instantaneous speed and their distance. The process consists in correlating the information obtained regarding vehicles in one and the same distance bracket during two consecutive processing time intervals, so as to determine, at each instant, the acceleration of each vehicle and a prediction of its speed, and in then detecting an incident in a distance bracket by detecting the passing of the speed of a vehicle below a given speed threshold. The advantages of the process resides in rapid incident detection in regard to a road or motorway network, with a view to informing the users rapidly.

Abstract: This invention comprises a system for calculating at least one vehicular traffic check parameter. The system according to the invention includes a pulse modulated radar placed at a high point at the side of the lanes to be monitored. The radar emits pulses having a frequency f.sub.o and width .tau. according to a radiation diagram. The radiation diagram is narrow in plan and sufficiently wide in elevation to cover all lanes to be monitored, and inclined in elevation and plan such that at least one range bin of the radar is included in a lane. Echo signals received by the radar are then processed by a signal processing module and a parameter extraction module. The invention is particularly useful in automobile traffic, for calculation of the number of vehicles travelling in lanes, the vehicles speed and length, etc. The advantage of the this inventive system compared with previous systems is that it enables simultaneous checking of several traffic lanes.