GM says DSRC expansion underscores need to protect 5.9 GHz

General Motors’ decision to offer vehicle-to-everything (V2X) technology in a high-volume Cadillac crossover vehicle by 2023—and to extend V2X to the entire Cadillac portfolio after that—underscores the importance of ensuring that automakers have access to spectrum, and that means protecting the entire 5.9 GHz band for roadway safety, according to GM.

In a letter to the FCC last week, GM noted the commitment the company is making to Dedicated Short-Range Communications (DSRC) beyond the Cadillac sedan it rolled out in 2017. At the annual meeting of the Intelligent Transportation Society of America last month, GM announced that it will extend hands-free Super Cruise technology to all Cadillac models and other GM brands and that it’s going to extend V2X to more vehicles.

GM says its V2X technology relies on DSRC and the entire 5.9 GHz band to communicate between cars and roadway infrastructure and to bring next-generation automotive safety to drivers everywhere. It’s another salvo in the ongoing battle between DSRC, a technology that was designated for auto safety two decades ago, and cellular-based V2X, which is newer and, some argue, a better choice for road safety. Automakers like GM and Toyota have embraced DSRC, while others, like Ford, are on the C-V2X bandwagon.

The FCC has been examining what to do with the 5.9 GHz band, some of which could be designated for Wi-Fi and/or other unlicensed use, but it’s been pretty much a stalemate. FCC Commissioner Michael O’Rielly even described the 5.9 GHz band as a “mess” as recently as May. The FCC was instructed to conduct tests to see how unlicensed devices can work in the band without causing harmful interference to those who want to use it for auto-safety purposes, but the test results haven’t been made public.

O’Rielly, a Republican, and Democratic Commissioner Jessica Rosenworcel have been particularly outspoken about the 5.9 GHz band and making more spectrum available for Wi-Fi. Back in February 2015, the two penned a blog saying they support safety initiatives associated with DSRC but feel it’s time to develop a compromise that allows both unlicensed and DSRC use in the U-NII-4 band. 

Toyota announced in April that it plans to deploy DSRC systems on vehicles sold in the U.S. starting in 2021, with the goal of adoption across most of its automotive lineup by the mid-2020s.