A novel location-based channel congestion control scheme in V2I networks

IEEE has adopted 802.11p/1609 as the standards for vehicular communications. The CSMA/CA based MAC in 802.11p leads to great performance degradation in dense networks, and the start-of-interval flooding collisions caused by the periodic channel switch in 1609.4 makes this problem even more severe. In this paper, an adaptive location-based channel congestion control scheme for the V2I (Vehicle to Infrastructure) communication is proposed. This novel method divides the service channel (SCH) interval into exclusive access period (EAP) and contention access period (CAP). In EAP, a location-based TDMA/CSMA scheme is designed to alleviate potential collisions, which could adapt to various traffic loads. In CAP, the default EDCA is employed. Vehicles´ remnant communication time in the network is considered to improve the overall system fairness. Simulation results reveal that the proposed scheme achieves significant collision reduction and system throughput improvement under saturated V2I networks compared with the IEEE 802.11p/1609.4 MAC scheme.