Happy Prime Day! Here’s one special deal you don’t want to buy: Microsoft’s grand plan to bring high speed broadband to the less-populated fringe of rural America for peanuts. It sounds appealing, but it has some major issues.

Microsoft is still promoting TV White Spaces, a speculative system that uses unlicensed spectrum to build wide area networks. Because spectrum is free, White Spaces advocates claim it’s a marvelous system for sparsely-populated areas.

But free spectrum is a barrier to network investment. Nobody wants to spend money on equipment that won’t work because too many others are on the same bands. Equipment for unlicensed networks needs to be dirt cheap.

Constant Demand for Bandwidth

The history of TVWS primarily consists of advocates petitioning regulators for more and more spectrum allocations. Microsoft wants the FCC and Congress to set aside three TV channels in every market – even the urban markets where spectrum is scarce.

The broadcasters are rolling on the floor laughing at this request:

Microsoft is currently reminding fans why some sequels should never be made. The latest entry in the tech giant’s Vacant Channel franchise is yet another heist movie based on a con game that’s too clever by half.

According to Microsoft, it is urgent that the Federal Communications Commission reserve a vacant UHF white space channel in every market nationwide following the post-auction repack of broadcast television stations, and Microsoft maintains this reservation can be accomplished without causing harm to television stations.

That’s nonsense on its face. The proposal is either unnecessary, because there will be plenty of spectrum, or it is harmful, because there will not be enough.

It appears that NAB is not a booster.

Microsoft’s Dubious Accounting

Microsoft commissioned a study from Boston Consulting Group that’s meant to prove TVWS is the best technical solution for areas with particular population densities:

New directional findings by The Boston Consulting Group suggest that a combination of technologies utilizing TV white spaces are the most efficient technologies to connect areas populated at densities from two to 200 people per square mile.

As the population thins, satellite becomes the most cost-effective solution because the infrastructure costs of building towers make TV white spaces, or any terrestrial wireless technology, less attractive.

In higher-density rural areas, higher-frequency 4G LTE technologies become the most cost-effective option.

Duplicative Solutions

Unlicensed wide-area networks have a history of failure. Advocates have been touting TVWS for 15 years, and all that’s come of it is some demonstration networks in some of the world’s poorest nations.

While policy wonks have been touting TVWS in DC, real networks in rural areas around the world run on satellites, Wi-Fi, WiMax, and 3GPP technologies such as 3G and LTE.

Spectrum is available in rural areas for unlicensed use already, because there is low demand for TV broadcast channels and 3GPP networks. So there’s no need for regulators to make more available.

The Real Problem is Equipment Cost

IEEE 802.22 is a reasonable approach to wide-area networks over unlicensed spectrum. It uses a technical approach similar to UWB, DOCSIS, and WiMax that divides channels into time slots and limits contention.

But there is low demand for 802.22 equipment, which leads to limited choices for buyers and high prices. The money saved by not having to pay for spectrum licenses is thus lost to high equipment costs.

The obvious solution is to design TVWS systems around standard technologies such as LTE-U. LTE-U interconnects transparently to standard LTE networks, so the cost equation is very good.

A Wildly Speculative Plan vs. a Practical Plan

TVWS advocates believe they can solve their cost problem by pushing TVWS equipment into crowded cities. The alternative is to pull LTE-based technology into rural networks.

It’s obviously much more practical to use technology already supported by an established industry than to deploy new technology. When the new tech has limited appeal, the decision is a no-brainer.

TVWS is folly. The best technical solution for 2 – 200 people per square mile rural locales is LTE and LTE-U. TVWS is too little, too late.