The FCC Thursday voted to take a new look at the 5.9 GHz (5.850-5.925 GHz) band to see whether auto safety communications and WiFi can share the same spectrum. For the past two decades, the entire 75 megahertz of spectrum in the 5.9 GHz band has been reserved for use by Dedicated Short-Range Communications (DSRC), a radio service designed to enable vehicle-related communications. However, after 20 years, DSRC still has not been widely deployed, according to the agency.
In the Notice of Proposed Rulemaking, the Commission proposes to designate the lower 45 megahertz of the band for unlicensed uses like WiFi. This 45 megahertz sub-band can be combined with existing unlicensed spectrum to provide high-throughput broadband applications on channels up to 160 megahertz wide.
The Commission is proposing to dedicate the remaining 30 megahertz of the band for use by transportation and vehicle safety-related communication services. Specifically, in the NPRM, the Commission recommends revising its rules to provide Cellular Vehicle to Everything (C-V2X), an emerging standard for transportation applications, with exclusive access to the upper 20 megahertz of the band. Under the Commission’s current rules, no spectrum is allocated for C-V2X. The NPRM seeks comment on whether to retain the remaining 10 megahertz for use by DSRC systems or to dedicate it for C-V2X use.
The Chairman intended to move on the 5.9 GHz proposal earlier, but the Department of Transportation voiced concerns, Inside Towers reported. Specifically, the DOT opposed allocating the entire band to unlicensed WiFi; the DOT also wanted all 75 MHz reserved for transportation safety, FCC officials told reporters. After months of “substantial” discussions, the result is a compromise that ended in “meaningful changes” to the item, said one Commission official.
“Today’s work by the FCC to open up more spectrum continues the good and necessary efforts to provide the raw resource underpinning the evolving U.S. wireless broadband marketplace,” said Louis Peraertz, Vice President of Policy for the Wireless Internet Service Providers Association.
“Taking fallow spectrum in the 5.9 GHz band and dedicating 45 MHz of it to new unlicensed uses will both improve WiFi performance and help extend commercial fixed wireless offerings which sit contiguous to the band.”
December 13, 2019