Wireless Sensor Networks for Intelligent Transportation Systems

Abstract

This paper presents a traffic monitoring system implemented through Wireless Sensor Network (WSN) technology within SAFESPOT Project funded by the European Community. The aim of this project is to provide a flexible, robust, low-cost and low-maintenance wireless solution for obtaining traffic-related data that can be used for automatically generating safety warnings at black spots along the road network. The WSN consists of one Gateway Node (GN) and n Sensor Nodes (SNs) deployed along the roadside according to an approximately linear topology. Each SN is able to monitor a section of road, collecting parameters such as vehicle count, speed and direction. Data from the SNs is collected by the GN and delivered to a Road Side Unit (RSU) responsible for fusing it with traffic-related data generated by alternative sources. The system has been tested and performance evaluated under a number of real use-case scenarios. Traffic monitoring, Wireless Sensor Networks In this paper we present one of the traffic monitoring solutions realized within SAFESPOT Project. The proposed solution is based on WSN technology and involves a network composed of one Gateway Node (GN) and n Sensor Nodes (SNs) univocally identified by their own address i=1,…,n. The GN is connected to the RSU through a wired interface. In general, the RSU is able to perform more advanced data processing than SNs and it could be connected to a number of GNs belonging to several WSNs. The WSN application follows a master-slave paradigm enabling bidirectional radio communication. The GN behaves as a master, polling the desired SN with requests and commands, while SNs play the role of slaves replying to the GN through data packets or acknowledgment (ACK) packets.