An Enhanced C-V2X Mode 4 Resource Selection Scheme for CAV Platoons in a Multilane Highway Scenario

This paper proposes an enhanced C-V2X mode 4 resource selection scheme for CAV platoons to support reliable intra-platoon message delivery. The enhanced scheme introduces three enhancement mechanisms, which aim to address merging collisions and hidden-node collisions in intra-platoon message delivery and enhance the sensing-based semi-persistent scheduling (SPS) scheme standardized by 3GPP. A resource partition mechanism is introduced to avoid merging collisions among vehicles moving in opposite directions; an intra-platoon cooperative mechanism is introduced to enable the leader of a platoon to know the resource occupation status on the hidden nodes of the platoon and thus avoid hidden-node collisions; and a packet collision detection mechanism is introduced to enable a non-platoon vehicle to detect and avoid merging collisions due to lane-change maneuvers. Simulation results demonstrate that compared with the standardized SPS scheme, the enhanced scheme can improve the efficiency of intra-platoon message delivery in terms of the intra-platoon packet delivery ratio.