Airband – Microsoft’s Moonshot To Connect Rural America Using TV White Spaces
Microsoft has announced an ambitious plan to help bring broadband to the approximately 23.4 million rural Americans that lack service with speeds of 25 Mbps downstream. Through its new “Airband” initiative, Microsoft will partner with rural telecommunications companies by covering certain capital costs of deploying TV White Space networks. Microsoft has set a goal of bringing broadband connectivity to 2 million people in rural America by July 4, 2022. Microsoft intends to have 12 projects up and running in 12 states in the next 12 months. White Space projects are planned for Arizona, Georgia, Kansas, Maine, Michigan, New York, North Dakota, South Dakota, Texas, Virginia, Washington, and Wisconsin. Further information on the Airband initiative is available in Microsoft’s rural broadband strategy white paper and on Microsoft’s website.
What Are TV White Spaces?
TV White Spaces are unused spectrum within the broadcast television spectrum bands (and the new 600 MHz service band). Certain areas of the country have more TV White Spaces than others because in those areas not all TV channels are utilized. For example, in rural areas there are fewer licensed TV broadcasters, and thus more unused 6 MHz-sized TV channels available for use. Under Part 15 of the FCC’s rules, TV White Spaces are available for use on an unlicensed basis.
TV White Space devices are classified as either fixed or personal/portable. Both types of devices must meet different requirements related to power output, frequency use, and antenna height. Prior to operation, all White Space devices must access a database to determine which vacant channels are available for use at their locations. Devices then transmit on available frequencies, but also have the ability detect primary users, move to new frequencies if necessary, and adapt bandwidth and power levels. White Space databases are administered by private entities that have been granted authorization by the FCC.
Characteristics Of TV White Space Low-Band Spectrum
Spectrum in the broadcast television bands and the 600 MHz service band is considered low-band spectrum because it is located below 1 GHz. Low-band spectrum is optimal for delivering wireless broadband access, especially in rural areas because it is able to travel much farther than mid- and high-band spectrum. Low-band spectrum also is able to penetrate walls and physical structures more easily than other spectrum. In contrast, higher frequency spectrum is better suited for providing capacity, such as in densely populated urban areas. These advantageous propagation characteristics of low-band spectrum make TV White Space technology a promising vehicle for delivering last-mile access.
The Cost Of Connecting Rural America & Microsoft’s Moonshot
Based on recent FCC deployment data, there are approximately 34 million individuals that do not have access to broadband service with speeds of 25 Mbps downstream, of which 23.4 million live in rural America. Microsoft estimates that it can connect these 23.4 million rural Americans to the Internet using TV White Space networks, at a total cost of roughly $10 to $15 billion. In contrast, Microsoft estimates it would cost 50 percent more to use LTE fixed wireless technology, roughly $15-25 billion. If fiber-to-the-home were used, it would cost 80 percent more, roughly $45-65 billion. Microsoft believes the “most optimal” deployment strategy would involve a mix of several broadband technologies, which could lower costs to about $8-12 billion compared with using TV white spaces alone.
You have to crawl before you can walk; walk before you can run. Microsoft’s Airband is meant to put a dent in the digital divide, not solve it. Microsoft has set an initial goal of bringing broadband connectivity to 2 million people in rural America by July 4, 2022. Microsoft plans to have 12 projects up and running in these 12 states in the next 12 months: Arizona, Georgia, Kansas, Maine, Michigan, New York, North Dakota, South Dakota, Texas, Virginia, Washington, and Wisconsin.
Broadcaster Opposition To TV White Spaces
As expected, TV broadcasters have been extremely critical of Microsoft’s push to reserve another channel in the broadcast bands for unlicensed use. Broadcasters consider all spectrum in the TV bands to be their spectrum, and they automatically oppose any proposal that would take any of it away from them or otherwise tread on their control of it. Those that are critical of broadcaster’s over-aggressive, defensive posture need to remember that licensed television services lack access to alternative spectrum bands. In comparison, the are numerous spectrum bands that may be used to provide broadband service.
Broadcasters view Microsoft’s proposal as an attempt to “steal” a TV channel. Now that the Incentive Auction has ended, broadcasters are about to be repacked, and when it is over, there will be fewer broadcasters on the air and less TV broadcast spectrum. Broadcasters argue that there is not enough spectrum to designate a channel in every market for unlicensed use. Besides, the proposal is a loser, they claim. Broadcasters argue that all prior attempts to use TV White Spaces for broadband have failed. They provide supporting data for this claim in a recent ex parte.
Microsoft's Altruism: Making Money Is Not Our Goal
Microsoft will provide upfront capital costs to launch the point to multi-point White Space networks. Generally, base station antennas and radios will be placed on a tower or the top of a building in close proximity to the intended service area. Preferably, the base station’s backhaul will be provided via fiber. End-user locations connect to the network using White Space customer premise equipment (“CPE”) and Wi-Fi access points. At the public announcement of the Airband initiative, Microsoft stated it will seek some sort of a revenue sharing agreement with each network operator to recoup the capital costs over time.
Microsoft arguably has way more experience with TV White Spaces than anyone else. It has helped launch successful TV White Space networks in Africa and other countries outside the U.S. To be sure, vacant TV channels are abundant in rural Africa and other less-developed countries, making it easier to deploy White Space networks. White Space technology allows vacant channels to be aggregated or bonded, which produces more robust connections and faster speeds for end-users. These networks in Africa are very impressive partly because the conditions are ideal. In a May 31, 2017 ex parte, Microsoft claimed that currently “there are 25 Affordable Access Projects globally leveraging TV white spaces, addressing a variety of challenges, and providing broadband internet access to 665,760 people.” The question, then, is can this success transfer over to the U.S.
Will It Work?
TV White Spaces were first opened up for use by the FCC in 2008, and development of related equipment and technology has been gradual. Certainly, there is nothing abnormal about the measured progress of the TV White Space ecosystem. Its growth tracks that of other technologies in wide use today. The world wide web wasn't built in a day. Remember the first cell-phones? They were heavy, the size of a brick, and sold for thousands of dollars.
Microsoft thinks TV White Space technology is nearing critical mass. Conditions for expanding the use of White Space devices have ripened because of the FCC's 600 MHz Incentive Auction. The FCC has rules in place allowing fixed and personal/portable TV White Space devices to operate in the TV bands, the 600 MHz service band, the 600 MHz duplex gap and guard bands, and channel 37 in some circumstances.
However, in order for TV White Spaces to be economically viable in the U.S., more spectrum is needed. Right now, White Space CPE is expensive. According to Microsoft, the antenna it typically uses at end-user locations costs around $800. But, it expects that price to fall to $200 in the next year. The White Space ecosystem has grown since the FCC first opened up the spectrum for use, and there continues to be increased interest among equipment manufacturers. But, the guarantee of a national footprint for White Space spectrum is needed to drive the mass-production of equipment. There must be at least three channels below 700 MHz available nationwide for unlicensed use for TV White Space networks to be truly successful. This is why Microsoft has been recently pressing the FCC to reserve another 6 MHz channel solely for unlicensed use. The FCC is expected to make a decision soon.
