1. Field of Invention
This invention relates to a system for preventing traffic accidents between vehicles and pedestrians; and more particularly, to such a system utilizing radio communication therebetween.
2. Discussion of Prior Art
Heretofore, a radar system on a automotive vehicle can detect a pedestrian in front of a automotive vehicle, but field of vision of a radar system is as narrow as a that of a driver of a vehicle, so it is impossible to detect a pedestrian who suddenly rushes out in front of a vehicle in advance. And a radar system uses a millimeter wave, which has a sharp directivity and goes straightly, so a radar system cannot detect a pedestrian behind edge of intersection.
Examples of the related are comprise: U.S. Pat. No. 4,543,577; U.S. Pat. No. 5,522,509 and U.S. Pat. No. 6,081,223; Simon et al , Spread Spectrum Communication Handbook, Revised Edition, McGraw-Hill, 1994; and Morris et al, Airborn Pulsed Doppler Radar, 2nd Edition, Artech House, 1996. However, the art leaves much to be desired in terms of traffic safety, prevention of accidents, and use of latest technology to improve the quality of life with respect to vehicle traffic.
Heretofore, traffic management center monitors vehicles by using DSRC, ultrasonic beacon and optical beacon using communication units both on a vehicle and on roadside. In this case units on vehicles are relatively expensive.
Accordingly several objects of our invention, it is possible to alarm and notify to a driver that a pedestrian locates near a vehicle, and call driver""s attention to a pedestrian, even if a pedestrian is out of a driver""s view field, and to prevent traffic accident. It is also possible to call pedestrian""s attention to an approaching vehicle.
And it is also possible to alarm and notify to a driver that a pedestrian locates behind edge of intersection and to call driver""s attention, so a driver can prepare for pedestrian""s rushing suddenly out in front of a vehicle in advance.
And it is also possible to support investigation for the cause of the traffic accident by recording ID code of a vehicle and/or pedestrian, with time and location by each unit on a vehicle and with pedestrian.
Accordingly several objects of our invention, traffic management center can communicate vehicles using relatively cheep on-vehicle unit and can monitor traffic values, vehicle speeds, a route of a specific vehicle, so as to control traffic and keep appropriate traffic flow.
Further objects and advantages of our invention will become apparent from a consideration of the drawings and ensuing description thereof.