Experimental Characterization of Delay and Age of Information in DSRC V2V

Abstract

In this paper, we demonstrate the real-time performance of Dedicated Short Range Communication (DSRC) through the design and development of a full-stack testbed based on open-source software that includes the IEEE 802.11p and the IEEE 1609 protocol suite. Vehicles broadcast periodic Basic Safety Messages (BSM). Reference mobility and data traffic models from 3GPP are used for scenario generation using ns-3. We show how to meet the timing requirements of the 802.11p lower layers using low-cost, commercial off-the-shelf components, based on open-source GNU Radio and tested with Ettus USRP B210 Software Defined Radio (SDR), 6 GHz Tx/RxRF frontends and GPS Disciplined Oscillator (GPSDO). The testbed is used to characterize the different contributors to the total delay budget and the Age of Information (AoI), a key metric for vehicle-to-vehicle (V2V). We observe that the AoI is impacted not only by the communication parameters but also by the mobility and traffic conditions. Our results show that more frequent BSM transmission reduces the average peak age but with a higher value relative to the inter-BSM period due to the collisions and packet losses.