| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To accurately calculate a traffic amount while protecting privacy. <P>SOLUTION: A road side controller installed on a road transmits a data string including a spot dynamic code 75 to vehicles existing in the communication area of the road side controller. The spot dynamic code 75 includes an N position code consisting of an area code showing the position at which the road side controller is installed and a count value counted by a counter. The N position code is transmitted and received between the road side controller and the vehicle, and traffic volume, speed, congestion occupancy ratio, special density, travel time, etc., are calculated by using the period of time when the N position code is transmitted and received. <P>COPYRIGHT: (C)2003,JPO</p> |
