中文摘要：

为了构建基于无线传感器网络的大规模、低成本、低功耗的交通信息采集系统，本文提出了一种车辆速度检测算法。将一跳通信范围内的路由节点和多个传感器节点看成是一个子网，路由节点实现子网内的时间同步和车速计算。通过实验验证了该车速检测算法的精度可达到95%左右。

英文摘要：

In order to build the wireless sensor network based large-scale, low-cost, low-power traffic information collection system, this paper proposes a vehicle speed detection algorithm. We divide the network into many subnets, and one subnet consists of one router and multiple sensor nodes. The router conducts time synchronization and vehicle speed computing for its subnet. The vehicle speed detection accuracy of the algorithm is verified by experiments.