Urban Fiber Based Laser Interferometry for Traffic Monitoring and Analysis

Accurate road condition monitoring is of great significance to alleviate urban traffic congestion and improve the urban environment. To monitor traffic flow on the road, mobile phone navigation service is preferred by most citizens, while it has a blind zone in heavy vehicle monitoring due to user deviation. With the help of laser interferometry, the widespread fiber network itself may undertake the sensing task. In this paper, we propose a fiber-based traffic monitoring method, to obtain the traffic flow of both heavy and light vehicles. This user-authorization free method can be an efficient complement to navigation services. The detected light vehicle flow is validated by traffic data from a mobile navigation company with correlation coefficient of 0.96. We also measure heavy vehicle's pattern for months including several special periods. During the cyber shopping extravaganza, the busy freight trade causes 2.2 times the heavy vehicle flow of usual time. On the contrast, necessary traffic control makes the heavy vehicles decrease to 0.2∼0.3 that of the usual time on national major event days. During the 2022 Beijing Winter Olympics, we find some Olympic related conveyance appearing in the evening. Those interesting phenomena suggest the practicability of fiber sensing in traffic monitoring, road health measurement, and its further potential in smart city foundation.