Ubiquitous access to the cloud via a shroud of mobility that devices simply connect to, without the user thinking about it, has been a goal of both the FCC (News - Alert) and operators for years now. But advancing a national goal of seamless and affordable mobile device connectivity will require an enormous increase in the availability of not just licensed airwaves, which the FCC is addressing with upcoming TV white space auctions, but also unlicensed spectrum capacity, according to new research.

Time Warner (News - Alert) Cable has announced the publication of a report on the effects of the growth of Wi-Fi consumer demand on existing unlicensed spectrum allocation, finding that, like in the 3G/4G world, high-bandwidth apps, video and increased usage in general threaten to outstrip existing resources. Rather than allow that to happen, report author Michael Calabrese of the New America Foundation concludes that it is critical that the FCC makes unlicensed spectrum into a component of federal spectrum policy supporting advanced digital communication needs.

Escalating Demand

As a test bed, he points to the fact that the cable industry has invested heavily in the deployment of more than 150,000 Wi-Fi access points across the country, with more being deployed every day. In addition to individual company deployments, five cable providers teamed up in 2012 to provide reciprocal wireless broadband access using unlicensed spectrum for each other’s subscribers nationwide.

The results of cable Wi-Fi and other public hotspot initiatives show that the embrace of Wi-Fi has nothing but upside, really: Studies calculate the annual contribution of the unlicensed wireless sector to the economy to be between $50 and $100 billion. Wi-Fi also expands the reach of cable broadband service and provides benefits to the broader community, including emergency response following SuperStorm Sandy in the New York/New Jersey area, and large public events like the Democratic National Convention in Charlotte, North Carolina.

But as deployment of Wi-Fi has expanded, usage has increased dramatically, threatening to bring that development to a screeching halt without the allocation of more spectrum to accommodate the growth, the report argues. Wi-Fi now accounts for an estimated 80 percent of all traffic from smartphones, tablets and other consumer electronic devices. In the U.S., more data is carried over Wi-Fi than any other Internet path.

"Time Warner Cable is a leader in deploying indoor and outdoor Wi-Fi networks in metropolitan and surrounding areas to better serve our customers and their communities,” said Fernando Laguarda, director of the program and vice president for external affairs and policy counselor at TWC. “In December 2012, the number of unique users accessing our network grew by over 720 percent, and data consumption per user grew by over 100 percent, compared to December 2011. Devices per user and average minutes per session have also increased. Our experience confirms that user demand for ubiquitous Wi-Fi coverage will continue to grow.”

Toward a New Spectrum (News - Alert) Policy

The preferred frequency range for wireless RF communications used in the access portion of the network lies in the span of roughly 300 MHz to 3 GHz. In the U.S., the 2.4 GHz band relied upon for Wi-Fi to date has become increasingly saturated—in fact, Calabrese said, the band could be exhausted by the end of 2014.

Meanwhile, next-generation gigabit Wi-Fi is currently not possible in any unlicensed frequency band suitable for Wi-Fi deployment in the U.S. today due to FCC rules. The gigabit Wi-Fi standards allow for increased throughput (meaning shorter transmission times, less battery consumption and a better customer experience), but they depend on access to 160 megahertz channels, which are not provided for by the FCC.

Opening up more access to Wi-Fi is good for consumers, but Calabrese argued that “The key policy obstacle to this positive outcome is progress on the FCC’s effort to open the most underused bands of spectrum—particularly federal spectrum and portions of the mostly empty TV band—for unlicensed sharing.”

Although the upcoming planned auction of additional TV band spectrum will inevitably result in fewer “white space” channels for unlicensed use, the FCC should reorganize the band to ensure the availability of at least 30 to 40 MHz of unlicensed spectrum in every media market, he said.

“This will require several band plan and rule changes: First, the guard bands needed to protect licensed services should be wide (e.g., a duplex gap of at least 20 megahertz), contiguous and designated for low-power unlicensed use,” he said. “Second, Channel 37 should be opened for shared, unlicensed use by relying on the existing geolocation database to enforce exclusion zones to protect incumbent services.”

Also, the two TV channels now exclusively reserved for wireless microphones should be opened for shared access by unlicensed broadband devices at the times and places they are not needed by microphones, he argued.

“There is no need to reserve any TV channel exclusively for microphone use, since mic operators have effective access to a large number of vacant TV channels that are not available for unlicensed use and that can meet their needs under ordinary circumstances. The FCC should require microphones to rely first on these out-of-market TV co-channels before falling back on a database reservation that makes a channel unavailable for unlicensed use.”

Beyond TV white spaces, Calabrese also recommended expanded use of the 5 GHz band to support existing outdoor Wi-Fi applications, and to open the federal 3.5–3.7 GHz band, which the FCC has earmarked for a low-power Citizens Broadband Service. Calabrese said that utilizing the latter “strikes the right balance between protecting incumbent operations (mostly offshore naval radar) and facilitating private-sector usage on a spectrally efficient, small-cell basis.”