Dynamic Adaptations of LPG-based Vehicular Ad Hoc Networks

In recent years, there have been significant research efforts related to vehicle to vehicle (V2V) communications. The major demand of the V2V communication is originally from safety-related applications; in addition, other possible application areas including communication support for traffic management have increased as well. Local Peer Group (LPG) is a partitioning structure to promote fast deliveries of time-sensitive information and efficient use of the wireless media. LPG organizes vehicles into manageable vehicle groups prior to the need for delivering relevant emergency messages, and provides efficient data dissemination (both multicasting and unicasting) among vehicles. As vehicles move in the roadways, wireless communication conditions undergo dynamic, continuous changes in terms of propagation performance, node density, and network topology. To maintain reasonable performance, V2V networks such as LPG need to dynamically adapt to such changes. In this paper, the authors first provide an overview of the LPG structure. As the focus of this paper, they then present a new framework to dynamically adapt the LPG network (i.e., Adaptive LPG) that supports efficient LPG communications in dynamically changing roadway environments. They identify and describe five adaptation areas of the adaptive LPG, and show dynamic transmission time scheduling as one detailed operational example.