Cisco Systems is asking the FCC to grant it more time to provide a prototype device demonstrating sharing techniques operating in the 5850-5925 MHz band, saying it needs time for internal testing.
Cisco noted that since the beginning of the FCC's public notice to revise rules to permit Unlicensed National Information Infrastructure (U-NII) devices in the 5 GHz band, it has championed a sharing proposal called "detect and vacate" that detects Dedicated Short Range Communications (DSRC) signals and then vacates the 5850-5925 MHz band.
Through its work with what's called the Tiger Team and through partnerships with the auto industry and Denso International America, Cisco has continued to develop and evolve its proposal to find the optimum way in which IEEE 802.11ac radios could share with DSRC radios without causing harmful interference to DSRC. It is working to enable DSRC systems to perform their safety-of-life mission, the company said.
"Due to prototype production timelines, and previously scheduled business travel on the part of Cisco staff overseeing the testing of the prototype (e.g., attendance at standards meetings), we will be unable to complete our internal review by July 30," Cisco told the commission last week. "But we believe that work can be completed very promptly in early August, and we will be well positioned to submit a device to you on or before August 18, 2016."
In 1999, the FCC allocated 75 megahertz of spectrum in the 5.9 GHz band for DSRC, which is an Intelligent Transportation Systems (ITS) technology that enables direct vehicle-to-vehicle (V2V) and vehicle to/from-infrastructure (V2I) communications. In recent years, a consortium of automakers, in cooperation with the U.S. Department of Transportation (DOT), has conducted research directed at deployment of DSRC systems, but it hasn't come fast enough for a lot of Wi-Fi advocates who would like to see part of the band allocated for Wi-Fi.
The FCC issued a Notice of Proposed Rulemaking (NPRM) in early 2013 that proposed adding 195 megahertz of additional 5 GHz spectrum for use by unlicensed devices such as 802.11. It also proposed a change that would allow the band allocated to DSRC to be shared with unlicensed devices such as 802.11.
Earlier this year, a group of U.S. lawmakers reintroduced the Wi-Fi Innovation Act, which directs the FCC to "move swiftly" in seeking comments and conducting tests to assess the feasibility of opening the 5850-5925 MHz band to unlicensed use. FCC Commissioners Michael O'Rielly and Jessica Rosenworcel have come out in support of exploring whether unlicensed services could operate in the U-NII-4 band without causing harmful interference to DSRC.
- see this Cisco filing (PDF)