The Florida Department of Transportation (DOT) has asked the FCC for permission to test cellular vehicle-to-everything (C-V2X) technology in the 5.9GHz band in Gainesville, Fla. According to the Florida DOT's application, the organization wants to test pedestrian and cyclist safety using 30 connected vehicle devices. The state wants to run the trial from December 2020 until December 2023.

What makes the Florida DOT's application to test C-V2X interesting is that the state already has a connected vehicle system deployed. But that system uses dedicated short-range communication (DSRC) technology, which is a similar protocol that is designed to enable cars and trucks to communicate with one another to avoid collisions. The Florida DOT's application notes that it wants to test C-V2X because many automakers and chip makers are starting to explore C-V2X instead of DSRC.

Commsignia, a Santa Clara, Calif.-based maker of V2X technology, is listed on the Florida DOT's application as the manufacturer of the connected vehicle gear that Florida wants to use in its C-V2X trial. Commsignia CEO Jozsef Kovacs said he couldn't comment specifically on the Florida trial, but he did say that the company is involved in many C-V2X trials in the US.

"We are seeing the number of trials and inquiries growing," he said. "And the size of the trials is increasing too."

C-V2X vs. DSRC
Automakers are doing more than just exploring C-V2X. Over the past year some have abandoned their plans for DSRC while others have stated their commitment to C-V2X.

For example, Ford Motor Company announced at CES 2020 that it will begin deploying C-V2X communications in all its new cars starting in 2022. This comes just a few months after Ford asked the FCC for permission to operate C-V2X prototype gear in the 5.9GHz band, which is currently allocated for DSRC service. Ford's application is still pending.

And while Toyota hasn't said it will support C-V2X yet, the carmaker did announce last April that it was no longer going to install DSRC in its cars starting in 2021. Toyota said its decision was based upon a lack of commitment from the greater automotive industry and concern with the FCC about its intention to preserve the 5.9GHz spectrum band for DSRC.

Roger Lanctot, director of automotive connected mobility at analyst and consulting firm Strategy Analytics, wrote about Ford's decision to equip its new cars with C-V2X by 2022 in a blog post. He said he believes Ford's announcement on C-V2X was a turning point in the industry. "All of a sudden, people see that there will be millions of cars with V2X and cellular is the way to go. Plus, 5G is not that far away."

Lanctot added that there are benefits to C-V2X that DSRC can't solve. For example, with C-V2X, cars will be equipped to communicate with pedestrians. "That's a huge game-changer," he said.

5.9GHz uncertainty
DSRC's lack of momentum has not been lost on the FCC. On December 12, the FCC voted unanimously to advance a proposal that would reallocate large portions of the 5.9GHz band to unlicensed use and for C-V2X specifically.

The FCC's vote designated the lower 45MHz of the 5.9GHz band for unlicensed uses like WiFi. The remaining 30MHz of the band will be for vehicle safety-related services using C-V2X and not DSCR.

The FCC wants C-V2X to have exclusive access to the upper 20MHz of the band. However, the agency is also seeking additional comment on whether the remaining 10MHz should be for DSRC or for C-V2X.

The FCC noted when it issued this ruling that the existing rules for the 5.9GHz band dedicate the entire 75MHz of spectrum to DSRC. The agency said it wanted to change that allocation because, after 20 years, DSRC still has not been widely deployed and the spectrum has remained mostly unused.

Commsignia's Kovacs said that his company's equipment can work with both C-V2X and DSRC. And while there is currently "great momentum" around C-V2X, he said that Commsignia doesn't believe that questions about the different technologies should delay deployment. He also said that he doesn't think the FCC should give 45MHz of spectrum in the band to WiFi and unlicensed. "We believe we need to protect this spectrum to have a future roadmap for C-V2X. We need to support future use cases for autonomous cars," Kovacs said.

Strategy Analytics' Lanctot notes that the FCC's ruling will likely fuel more debate about DSRC vs. C-V2X. He said that, although the agency is currently considering allocating 10MHz of spectrum for DSRC, the C-V2X folks will likely be opposed to that decision because of the risk of interference. In fact, he sees the FCC's new ruling as a near-fatal blow to the future of DSRC.

— Sue Marek, special to Light Reading. Follow her @suemarek.