道口车流量监测系统设计

Design of the vehicle flux monitoring system at the roadway

一种基于同轴线的分布参数,以同轴线为敏感器件的微变电容式传感器研制成功并被应用到道口车流量监测系统中。该传感器由同轴电缆、单片机系统、高频检测电路和低频检测电路等几部分组成。根据同轴线的高频特性产生的脉冲信号的信息来判断车型;依据同轴线的低频特性产生的脉冲信号的信息,比较准确地判断出车速和车流量等信息。论述了道口车流量监测系统的原理与应用,实验结果表明利用微变电容式传感器设计的道口车流量监测系统具有较好的应用效果。

A microchange capacitive sensor using the concentric cable as sensing devive based on the distributing parameter is designed successfully and is used in the vehicle flux monitoring system.The sensor is consisted of a concentric cable,a single chip processor system,a highfrequency detecting circuit and a lowfrequency detecting circuit etc.The pulse signal created by the highfrequency property of the concentric cable is used in judging the vehicle type, and that created by lowfrequency property is used in estimating the vehicle flux and speed.The principle and application of the system are discussed.It is proved in the experiment that the system is valid.