Packet Rate Control for Maneuver Coordination in Congested V2X Communication Environments

Maneuver coordination is envisioned as a future Vehicle-to-Everything (V2X) communication-enabled application for cooperative driving to improve the safety, comfort, and efficiency of driving. A Maneuver Coordination Service (MCS) is currently being standardized to facilitate negotiation and coordination of cooperative maneuvers for the Connected and Automated Vehicles (CAVs) by exchanging Maneuver Coordination Messages (MCMs). In order to ensure fair use of available communication channel resources and limit the channel load to reduce message collisions, the European Telecommunications Standards Institute (ETSI) has defined a Decentralized Congestion Control (DCC) framework with packet rate control at the access and facilities layer. However, the DCC mechanisms are content agnostic and can have a negative impact on the MC application in congested communication environments. This paper proposes a new method by combining an adaptive DCC mechanism with a no packet rate control method for important MCMs during the negotiation and execution of safety-critical and emergency maneuvers. A simulation environment is used to extensively evaluate the new method and demonstrate its advantages over the standardized approach. A challenging V2X scenario with a high number of vehicles is simulated in congested V2X channels with only MCMs and with a mix of V2X message types. The results demonstrate the significant improvement of the proposed method for packet rate control for the MCS.