Performance comparison of IEEE 802.11p and ARIB STD-T109

Vehicular networking is moving from pure research to first deployments around the world. This shifts the focus of research and development to aspects like higher layer performance; yet different regions (Japan, Europe and the U.S.) employ vastly different lower layer protocols for medium access and transmission. Without means to compare their performance it remains unclear to what degree simulation results obtained for one region (that is, one set of lower layer protocols) can be transferred to the other. Our paper fills this gap by conducting an extensive simulation study comparing the performance of IEEE 802.11p and ARIB T109 taking into account both their differences on the physical layer (5.9 GHz vs. 700 MHz band) as well as in medium access (pure CSMA/CA vs. a combination with TDMA). We base this study on the first Open Source implementation of the ARIB T109 standard we developed for the vehicular network simulation framework Veins. This also encompasses parameters for a computationally inexpensive shadow fading model for urban environments. We briefly report on the results of an extensive measurement campaign that underlies these parameters.