Hybrid work zone information system with portable changeable message signs and dedicated short-range communication

The future deployment of dedicated short-range communication (DSRC) technology requires that applications with their bases in DSRC be integrated with existing traffic management techniques so that vehicles not equipped with DSRC at the early stage of DSRC deployment can also reap the potential benefits of DSRC technology. A hybrid traffic information system was successfully developed; it combines DSRC technology and portable changeable message signs (PCMSs) for use in the work zone environment to improve traffic mobility and thereby driver safety. The developed system uses DSRC-based vehicle-to- infrastructure and vehicle-to-vehicle communication to acquire travel safety parameters, such as travel time (TT) and the starting location of congestion (SLoC), and to disseminate these parameters to DSRC-equipped vehicles and PCMSs, which are strategically placed along the roadside. Through the use of the DSRC-PCMS interface developed and demonstrated in this work, PCMSs can receive these travel safety parameters from nearby DSRC-equipped vehicles on the road through DSRC-based vehicle-to-vehicle communication, and display them for the drivers of vehicles that lack DSRC capability. Such a system can be useful during the early stage of DSRC deployment when DSRC market penetration is low. In addition, a rigorous analysis was conducted to investigate the minimum DSRC market penetration rate needed for successful functionality of the developed system with respect to both acquisition and dissemination of TT and SLoC. Through the use of a realistic traffic flow model, guidelines were developed to estimate a minimum DSRC penetration rate needed to deploy the developed system for a variety of traffic scenarios on a given work zone road.