Congestion control by in-vehicle traffic shaping for vehicular safety applications

Enabling wireless communication between vehicles is seen as the next step towards enhancing road safety. This would allow frequent exchange of messages about the current status of the vehicles or its surroundings to ensure awareness and warn drivers about potential dangers. A major challenge to support such vehicular networks is the performance degradation caused by wireless channel congestion with increasing vehicular densities. This thesis presents an approach to improve the LTE uplink channel congestion problem by regulating message transmissions from the vehicle based on network load. An in-vehicle traffic shaper based on multiple token buckets as well as several application specific enhancements are proposed. Simulation show that the proposed mechanism provides better awareness compared to a pure data rate limiting approach under high vehicular densities as well as high in-vehicle data generation rates.