Can We Get Better Wi-Fi Without Jeopardizing Traffic Safety?

Spectrum for "intelligent vehicle-highway safety"? It's complicated.

It might not be surprising that major industries would mount a big fight over how to deploy a swathe of currently unused spectrum. However, a dispute over a chunk of spectrum located in the 5.9 gigahertz (GHz) band also pits different parts of the federal government against each other and, even in Washington’s ever-more partisan environment, has Republicans and Democrats on both sides. As such, the dispute offers some important insights into the political gamesmanship surrounding spectrum allocation.

You don’t need to know what a giga or a hertz is to understand that the spectrum in question is right next door to spectrum that has been set aside for unlicensed use. You don’t really need to know what “unlicensed use” means to understand that the most important unlicensed use now and for the near future is for Wi-Fi. The band that most of us use for Wi-Fi these days is down at 2.4 GHz, but that spectrum is crowded. Newer wireless technologies that can accommodate much higher data transfer, including a newer flavor of Wi-Fi referred to as 802.11ac (again, don’t ask, but this, too, is really important) operate higher up, in the 5 GHz band. Thus, existing and future wireless devices don’t need to be modified to use the 5.9 Ghz spectrum right next door. That is why there is a fight.

A long, long time ago, in 1991, at a time when the Internet was little more than a plaything for computer scientists, the automobile industry began to press for a set-aside of spectrum to be used for “intelligent vehicle-highway safety” systems that could help manage traffic and, most importantly, avoid vehicle collisions. The thinking, at the time, was that this could be accomplished with “roadside” safety systems that would create “intelligent highways”; few people at that time thought that technology could control individual cars, much less the driverless “autonomous vehicles” that are now being tested on the nation’s highways. In 1997, the automobile industry asked the Federal Communications Commission to dedicate a band of spectrum to be set aside for this use, in what came to be called the “Intelligent Transportation Systems” (“ITS”) band. The next year, Congress told the FCC to make crash avoidance a priority, and, in 1999, the FCC identified a large chunk of spectrum at 5.9 Ghz band to be licensed for that purpose. (This is confusing, but both the frequency of a wavelength and the bandwidth of spectrum are expressed in “hertzes.” In this case, the bandwidth is 75 MHz, which is a lot.) While this was a reasonable estimation of how much spectrum might have been needed in 1999, technology has advanced so that the same job can now be done with a lot less spectrum.

In the years that followed, the demand for additional unlicensed spectrum for Wi-Fi, the “Internet of Things,” and other purposes has surged. Meanwhile, the automotive industry reported periodically that it was testing and developing technology using the reserved spectrum. In the view of the technology community and the FCC, what the industry was really doing was “warehousing” -- i.e., sitting on -- the idle spectrum rather than putting it to productive use.

Meanwhile, technologies have changed and advanced. No one talks much about “intelligent highways” anymore, because it is now possible to put the brainpower right into the cars. Instead, technologists are focused on cars that can talk to each other, not to the highway. Importantly, new and better crash avoidance technology using other bands of spectrum has been developed and actually deployed. (You may have seen Volkswagen’s “It brakes when you don't” commercial demonstrating the company’s on board radar.) Depending on who is doing the talking, the automobile industry doesn’t care too much any more about using large portions of its allocation for safety, but is focused upon commercial applications which can generate user fees and advertising revenue. Wi-Fi proponents point out that most of these commercial applications are being delivered today by existing cellular and Wi-Fi networks.

In light of these changes, much of the tech community and public interest advocates want at least some of the thus-far underutilized spectrum to be reallocated for unlicensed use. They point out that unlicensed use is very efficient, since many users can share the same spectrum. Moreover, they say, technology has obviated the need to set aside the entire 75 MHz band exclusively-licensed spectrum for automotive use. They also argue that, at the time the ITS band was created, the focus was on safety and crash avoidance, but these purposes can be accomplished with a smaller part of the band. The real reason the auto companies want to keep the rest of the spectrum allocation is to promote commercial businesses unrelated to safety.

(There is another dimension to the fight over the ITS spectrum, which is that some public interest groups believe that the technology that the industry has developed poses grave privacy and cybersecurity risks. For more about that, you can read this petition.)

Not surprisingly, the automotive industry disagrees. It says that it has relied upon the FCC’s initial actions to develop important life-saving technology which is on the verge of deployment. It argues that spectrum-sharing will generate harmful interference for these services, so that
it does need the entire 75 MHz block to provide “interference free” service.

Here is where politics come into play. Two parts of the federal government have tended to view these questions differently. Through the National Highway Traffic Safety Administration (“NHTSA”), the Department of Transportation sees its job as promoting auto safety, and has long worked with the industry to achieve that goal. The FCC wants spectrum to be used efficiently and regards broadband deployment, through increased availability of wireless spectrum, as critical to promoting the broad societal goals embodied in the public interest standard of the Communications Act. Not surprisingly, the two agencies have different views on how to proceed.

So, too, do the different Congressional committees that have jurisdiction over NHTSA and the FCC approaching the issue from the perspective of the agency they control. (Here, for example, is a bipartisan letter from Senators Thune (R-SD), Rubio (R-FL) and Booker (D-NJ) pressing for unlicensed use of the 5.9 GHz band.) And, although the FCC is an independent agency that is not directly subject to Presidential control, all sides have prevailed on the White House to intercede.

There is little public indication as to when and how the FCC will proceed on this question. However, it would seem that the FCC’s commitment to broadband deployment and its desire to promote spectrum sharing will make it lean towards doing something to promote those objectives.

By Andrew Jay Schwartzman.