A DMAC Protocol to Improve Spatial Reuse by Managing the NAV Table of the Nodes in VANET

Several MAC protocols using directional antennas have been proposed to improve capacity in MANET by improving spatial reuse and communication throughput. Although transmissions using the directional MAC protocol are expected to provide significant improvements, they cause problems such as the deafness and fairness problems. High-mobility VANET has a particular problem using the DMAC protocol because vehicles can interfere with each other in contention for transmissions. In this letter, we proposed and evaluated a suitable DMAC protocol for VANET. As a result, spatial reuse increased the average throughput by 40% over omni-MAC, and 20% over general DMAC, while jitter showed a 17% decrease over both protocols. With these results, we confirmed the efficiency of the proposed protocol for use in VANET which requires fast access and reliable data transmission.