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195 MHz of new spectrum: A first look at the FCC’s proposed rules

By Matthew Gast in · HiveMind Blog · March 6, 2013


In January at CES, the FCC Chairman made an announcement that the FCC was poised to act to open up 195 MHz of new spectrum. At that point, I wrote that the announcement was promising but we would have to wait until February 20 to see the proposed rules.
Well, the rules are out. If you want to follow along at home, the proposed rules are in a Notice of Proposed Rulemaking (NPRM), numbered 13-22. When an NPRM is released, it kicks off a comment period after the proposed rules are published in the Federal Register.
I’m still working through what the rules say, but the high-level summary is a good one. Although the laws passed by Congress instructed the FCC to study releasing 120 MHz of spectrum, the Commission went farther and opened up 195 MHz. A key figure from the NPRM shows where the new spectrum lies.
Reading the NPRM, there are a couple of items which come across clearly. Most importantly, the Commission has fully absorbed the lessons of unlicensed spectrum, referring numerous times to the low barriers to entry for new technologies and how “[c]reating ways to access spectrum under a variety of new models, including unlicensed uses, increases opportunity for entrepreneurs and other new market entrants to develop wireless innovations that may not have otherwise been possible under licensed spectrum models.”
For a product developer, it is also wonderful to see the Commission thinking about simplifying the regulatory process.
One of the major efforts of the proposed rules is to simplify the technical requirements for 5 GHz unlicensed devices by converging on one unified set of rules that cover the entire 5 GHz band. Product developers benefit from simplified rules because the reduced cost and complexity of product certification translates into cheaper and more rapid product development.
I was also pleased to see the FCC thinking about international implications of their rules. When multiple regulators work together to create one set of rules that apply throughout the world, it means that product developers have only one target to meet. The FCC’s notice had a particular interest in “ongoing industry standards activity and international efforts to harmonize uses of the 5 GHz band to make more efficient use of the 5 GHz spectrum.” (The regulatory gurus in our industry will be quite busy responding to this request for information.)
The second item that comes across is how the evolution of Wi-Fi itself is influencing commission thinking.
The 2.4 GHz band was originally set aside for unlicensed use because it was “junk” that was polluted by numerous other transmitters. Even though the somewhat noisy 2.4 GHz band was not the most fertile soil to plant a new technology, Wi-Fi has proven to be hardy and adaptable.
802.11ac is mentioned about twenty times in the proposed rules, and the proposal specifically asks for information “on how the introduction of [802.11ac] might be implemented in the UNII bands and how these developments should inform our consideration of technical requirements for these bands and sharing technologies and techniques…”
Translation: We want these new rules to enable Wi-Fi, not hinder it.
In fact, the proposal even goes so far as to ask “whether some technologies or techniques, such as DFS, might limit the types of applications that could be implemented in the U-NII bands, particularly if wider bandwidth devices are deployed in this spectrum.”
The influence of Wi-Fi is shown even stronger in some of the comments made by commissioners. My favorite commissioner, Chairman Genachowski, refers to Wi-Fi seventeen times in just a couple of pages. His comments address the threat of congestion on Wi-Fi networks, the ability of Wi-Fi to augment licensed network coverage, and the promise of gigabit Wi-Fi to improve coverage and capacity in high-density areas.
Commissioner McDowell specifically talked about the need to make the 5 GHz band able to support 802.11ac and its new wide channels. (When you need regulatory support to enable wider channels, it’s a great boon to see the regulators trying to provide exactly what you want!)


Matthew Gast (@MatthewSGast)

Matthew Gast is Director of Advanced Technology at Aerohive Networks. He currently serves as chair of both the Wi-Fi Alliance's security task groups, was the first chair of the Wireless Network Management Marketing task group, and is the past chair of the IEEE 802.11 revision task group. Matthew is also the author of 802.11 Wireless Networks: The Definitive Guide (O'Reilly), which is now in its second edition and has been translated into six languages. His companion book, 802.11n book, 802.11n: A Survival Guide (O’Reilly), was recently published and provides information on how 802.11n works and what it means for the WLAN planning process. Most recently, Matthew completed 802.11ac: A Survival Guide (O'Reilly).