On the role of wireless sensor networks in intelligent transportation systems

Currently Vehicular Ad-hoc Networks (VANET) are receiving great attention by researchers because of their potentiality for developing innovative applications in the Intelligent Transportation Systems (ITS) context and are expected to be a widely adopted technology in the medium/long term. However, for the near future, the adoption of this technology is difficult since its performance relies excessively on its penetration rate into vehicles. In addition VANET are only able to gather information about the road while vehicles equipped with the appropriate technology are nearby, otherwise information can only be obtained by expensive and therefore scarcely deployed Roadside Units (RSU). Wireless Sensor Networks (WSN), on the contrary, can be deployed along a road (or in a parking lot area) with very little installation and maintenance costs. They can be used to constantly acquire information related to the road condition and the traffic state and, in addition, execute collaborative in-road processing for safety purposes. These properties make WSN an effective complement to VANET, since they can cooperate with them in order to mitigate their limitations. On the other hand, WSN deployments can also benefit from VANET and other communication technologies such as cellular networks in order to disseminate the information gathered to distant places. Consequently, WSN can also play a major role in ITS.