BLUEEYE: A BLUETOOTH-BASED VEHICLE LOCATION IDENTIFICATION SYSTEM FOR QUEUE LENGTH ESTIMATION AT SIGNALIZED INTERSECTIONS

摘要

Measuring or estimating vehicle queue length at signalized intersections is important for traffic signal performance monitoring and optimizing. Various technologies have been employed to estimate vehicle queue length at signalized intersections by using different means such as inductive loops, road side sensors, vehicle-to-infrastructure communications, etc. Such of existing technologies are have the disadvantages of being invasive, high cost to deploy, hard to maintain or limited to modern vehicles. In this paper, the authors propose the Bluetooth technology as an alternative option due to its simplicity, cost-effectiveness, low maintenance requirements, and privacy preserving nature. The proposed BlueEye system is for estimating vehicle queue length at signalized intersections by vehicle location identification. It relies on the received Bluetooth radio signal strength for location estimation since the signal strength fundamentally varies depending on transmitter distance. By providing BlueEye system with the signal strength distribution over vehicle locations at a traffic intersection, it becomes possible to identify vehicle locations at the site using a probabilistic approach. Despite the noise and randomness associated with the Bluetooth radio signals, and the dissimilarity between mobile devices, BlueEye showed high accuracy with limited location error.