FCC Approves White-Space Use for Unlicensed 'Super WiFi'

By Wayne Rash  |  Posted 2010-09-24 Email Print this article Print

News Analysis: The FCC's move is only the first step in making broadband wireless generally available on unused former television buffer frequencies.

When the Federal Communications Commission issued its press release about the approval of additional unlicensed spectrum in what are called "white spaces," it referred to the coming technologies as "Super WiFi." 

In reality, it's not clear that this previously unavailable set of unused frequencies will necessarily become anything that resembles WiFi. As the FCC points out in its statement, this is spectrum space that's going to be available to a wide range of technologies, of which wireless broadband is only one. Even if this turns out to be a significant use of these white space frequencies, it's not clear whether WiFi (or something like it) will be related in any way. 

The white space decision allows the use for a variety of unlicensed services of the former guard bands between television channels. These guard bands were there to protect the signals from one station against being interfered with by an adjacent station. Because analog television signals were a combination of an AM signal and an FM signal, the required bandwidth could be slightly unpredictable. In addition, the technology at the time, especially in the old analog television sets, really didn't have the ability to zero in on one channel and block out transmissions that were close to the same frequency. 

Now that television has moved to digital signals, this has all changed. Those guard bands are less necessary, and interference is less of a problem. But that's not the same thing as saying there's no possibility of interference with commercial broadcasting, because there is. As a result, the FCC has to make sure the devices that use these frequencies meet certain standards in terms of power output, frequency accuracy, transmission type, etc. In addition, because there won't be unlimited spectrum available, the FCC has to determine what the best use of a particular set of frequencies might be. 

In the case of data communications, or the "Super WiFi" that the FCC talks about, this could mean, among other things, that the FCC might require interoperability among the carriers providing this service. So just as any WiFi device has the ability to connect to a WiFi access point, the FCC might decide the best use of the limited spectrum is to let any white space device communicate with services on those frequencies. 

On the other hand, it's possible that the FCC might sell this spectrum to mobile carriers, perpetuating the four closed-carrier systems that persist in the United States now. Right now, while the FCC is trumpeting its achievement at getting all sides to agree on ways to avoid interference with existing licensed services on these frequencies, the fact is that we don't really know any details about how this will ultimately shake out. 

When Clint Boulton wrote about the FCC's White Space decision, he quoted Google's counsel expressing delight at the event. But what the FCC needs to ensure is that these frequencies aren't made the exclusive domain of Google, Microsoft or any other specific entity. Right now, both companies are experimenting with content delivery in the white-space frequencies, but they're using it for fairly proprietary purposes. If this resource is really going to contribute to the FCC's National Broadband Plan, what needs to exist on these frequencies is free and open access to high speed Internet connectivity. 

Note that by free, I don't mean it won't cost anything. What I mean is that it should be free of restrictions. Google shouldn't be able to tie up a set of frequencies for its exclusive use, and neither should any other company. If these frequencies are to achieve their intended purpose as stated by the FCC when it agreed to open them to unlicensed use, then they need to be available to anyone with the right device. 

For this to work, there must be standards, much like those the WiFi Alliance has created for WiFi use. The reason WiFi has been so successful is because the standards require interoperability. New versions of WiFi are backward-compatible with older versions, an old 802.11b device can still communicate with an 802.11n access point. These standards mean that you don't have to buy a particular wireless device to work with a specific access point. Instead, everything works together. 

Right now the FCC's new white space proposal doesn't include any requirement for standardization. In fact, right now there really aren't any specific rules or guidelines beyond some that protect broadcasters and wireless microphone makers. It's possible that some industry group will step in and create a set of standards and a certification process, which is what happened with WiFi. It's even possible that the WiFi Alliance will take this on, since they at least know how to make this work.  

But at this point, none of this has happened. While the FCC's action is cause to be hopeful, it's hardly cause for celebration. First, we have to find out the details of what the FCC has in mind. 



Submit a Comment

Loading Comments...

Manage your Newsletters: Login   Register My Newsletters

Rocket Fuel