Control-based scheduling with QoS support for vehicle to infrastructure communications

This article is focused on data transmission scheduling in V2I communications, where a central station, the roadside beacon, decides how to allocate system resources among the vehicles under coverage. We consider non-safety applications whose commercial appeal is expected to accelerate the deployment of VANETs. In this case the main objective is to deliver as much information as possible during the connection lifetime of the vehicles, which is limited by their speed and the length of the road sections under coverage. In this environment the contention free poll-based access mechanism of the 802.11e standard included in current VANET specifications is especially suitable. The design of a scheduling mechanism is addressed in this article from a control theory point of view with the additional novelty of using an optimal control formulation comprising resource constraints. This design strategy allows QoS differentiation, assuring a fixed amount of bandwidth for each QoS class. The resulting algorithm not only maximizes the amount of data delivered, but also reduces performance differences between users traveling along different roads.