Receiver-centric physical carrier sensing for vehicular Ad Hoc networks

The sender-centric medium access has been widely deployed to avoid interference in vehicular ad hoc networks, even though sender-centric physical carrier sensing suffers from exposed terminal problems and sender-centric virtual carrier sensing is relatively vulnerable to interference. In this paper, we propose a new receiver-centric MAC protocol, called RIMAC, to increase spatial reuse and network capacity. In RIMAC, the receivers accurately assess their channel status opposed to the sender initiated approach where senders can only heuristically infer that of their receivers. Therefore, the receiver-centric approach achieves a better level of spatial reuse with the same degree of interference prevention. Through both extensive numerical analysis and simulation studies, we find that the proposed receiver-centric MAC achieves up to 68 % higher network capacity than traditional sender-initiated approaches.