In response to a request for comment filed by the U.S. Department of Transportation last December seeking insight on how best to deploy vehicle-to-everything or V2X communication systems, the American Association of State Highway and Transportation Officials stressed that future cooperative and collaborative development needs to occur without disrupting investments in current technology.
“Cooperative systems achieved through communication between vehicles, infrastructure, and other users will provide an enhanced layer of safety and must be advanced,” the organization said in its Feb. 20 comment letter. “This ability to communicate will be essential for extending the range of vehicle-based sensing and achieving the full potential of safety benefits envisioned by connected and automated vehicles or CAVs.”
Yet AASHTO pointed out that such “collaboration” will take time, which is why “it is critical” that the current 5.9 GHz communication spectrum band “continue to be reserved for transportation safety purposes.”
However, USDOT noted in its request last December that “there are more than 70 active deployments of V2X communications with thousands of vehicles already on the road. During this time, there have also been developments in core aspects of communications technologies that could further support V2X in addition to Dedicated Short-Range Communications [DSRC], including Cellular-V2X [C-V2X], [and] the development of potential ‘5G’ communications or other future transportation safety technologies.”
AASHTO noted that “one of the biggest risks our member agencies face is the uncertainty over whether or not USDOT will fully support DSRC as the only proven technology that will enable the development of a CAV environment. The transportation industry cannot wait on deploying what has been proven to work today with something that may hold better promise sometime in the future.”
The organization reiterated that the only CAV communication technology ready for deployment now is DSRC, while V2X and other systems remain “either in the testing phase or concept stage at this point.”
If the industry is to successfully reserve the 5.9 GHz spectrum for transportation safety use, AASHTO argued in its letter, then it is “imperative” to focus on deploying the technologies that “are ready now, with the understanding that the technologies will evolve.
“What is most important is that each vehicle is able to hear and understand every other vehicle,” the group said. “This would realize the full potential of V2X communications and result in more lives saved and increased mobility.”