A letter from private sector businesses and organizations to the Federal Communications Commission, and Departments of Transportation and Commerce, agreeing on a single set of principles to examine use of the 5.9 GHz band by unlicensed devices, arrives like the fall weather – crisp, clear and a relief from the heat and humidity of summer. This letter lays out a clear path forward for determining whether sharing in the 5.9 GHz band can take place without causing harmful interference.
And even more noteworthy, members of the Senate Commerce Committee had a strong hand in moving the parties into agreement – demonstrating once again that a bit of well-executed oversight can have a tremendously positive impact on issue resolution.
For a while now, we’ve been reading cringe-worthy news reports about different segments of the industry supporting violently different views of what the 5.9 GHz band should become. Because the 75 MHz of radio spectrum (5850-5925 MHz) sits adjacent to a large swath existing unlicensed spectrum, the notion is that in some way, it may be possible for unlicensed technologies (such as Wi-Fi) to utilize bits of the 5.9 GHz radio spectrum that incumbents (such as intelligent transportation systems) are not using.
But that simple idea has itself generated controversy – exactly how would that happen? And who decides? Based on what? After all, the incumbent ITS uses are “safety of life” uses – designed by the Department of Transportation and auto industry to enable unimpaired drivers to avoid dangerous and even deadly accidents and road conditions.
Full disclosure: Cisco has been working on technology that would allow Wi-Fi to share the 5850-5895 MHz portion of the band while ensuring current and planned ITS uses could use the band undisturbed by radio interference. Cisco believes that we can listen, detect, and avoid ITS uses of the band, and that the benefits of using this spectrum – away from active roadways where ITS use would be prevalent – are huge. Cisco also offers solutions to the transportation sector that include ITS radios. As a result, Cisco is strongly interested in a “win-win” for the two radio communities of interest.
What’s to admire about this letter?
For starters, it embraces the view that regulators ought to consider having different systems share the same radio spectrum – provided that that there is an objective fact-based case to demonstrate that the systems with superior rights are protected from interference.
That’s good for consumers, because:
(1) it ensures driving will be safer ;
(2) it ensures we’re using radio spectrum resources as intensively as possible; and (3) if we can make Wi-Fi share effectively, that means more Wi-Fi channels will be available for broadband connectivity.
We also agree – the FCC, in close coordination with the DoT and other federal agencies – should take the lead to ensure that testing and modeling support a future decision to open the band for shared use. The FCC has the appropriate skills and expertise to understand how to evaluate the complexities of advanced radio sharing, while the DoT understands best what the ITS radios must be able to achieve from a performance standpoint when installed in cars and on roadways.
We also agree that the parties and agencies should utilize the FCC’s docketed proceeding to ensure relevant data and testing are available on the public record for any interested party to access. This is the best mechanism to ensure all sides are heard.
And we strongly agree that the process of evaluating new technologies for sharing should not be held to a simplistic deadline, after which the examination is abandoned in favor of some other approach.
When Wi-Fi embarked on an effort in 2002 to open up other sections of the 5 GHz band to unlicensed use, it took nearly four years before the FCC adopted final rules that permitted Wi-Fi to share the band with governmental radars. The process of opening new spectrum to sharing is complex and contains unexpected twists and turns that cannot be anticipated.
Congratulations to the Senate Commerce Committee for aligning the parties around a path forward, and to the private party signatories for thinking through what they could agree on, instead of continuing to disagree.
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