Spectrum, Spectrum, Spectrum
By Paul Kruczkowski, Editor
The National Telecommunications and Information Administration (NTIA) recently released its assessment on the viability of making the 1755-1850 MHz band available to wireless carriers within 10 years and the 1755-1780 MHz portion available within 5 years. The report concluded that while it is, in fact, possible to clear the entire 95 MHz for commercial use within 10 years, it will be a significant challenge to relocate the more than 20 federal agencies currently utilizing more than 3100 frequency assignments to other bands, all while allowing them to maintain comparable capabilities. The analysis estimates the transition costs at $18 billion and acknowledges that it is unlikely some federal systems would be able to meet the 5- and 10-year transition timelines.
Soon after the NTIA report was released, CTIA-The Wireless Association responded, stating that the immediate focus of the NTIA and Obama administration should be on the 1755-1780 MHz band, which has an AWS-3 (2155-2175 MHz) pairing identified in the recent spectrum legislation. CTIA added that they would be concerned if the effort to clear this part of the band was delayed until services in the entire 1755-1850 MHz band were relocated.
CTIA’s comments reflect the urgency of the situation in which its members now find themselves. Wireless carriers are in desperate need of additional spectrum, both to keep up with increasing data usage demand and to continue on the path to deploying LTE Advanced technology. Ericsson has predicted that mobile data traffic will grow tenfold by 2016 (driven principally by video), and the FCC has projected that growth in wireless data demand will lead to a spectrum deficit of 275 MHz by 2014 if no new spectrum is released. The old real estate mantra “location, location, location” has been replaced, at least in the broadband wireless industry, with “spectrum, spectrum, spectrum.”
The FCC and NTIA have been working together to free up spectrum for auction. The NTIA’s report assesses part of the FCC’s 2010 Broadband Plan, whose goal is to make 300 MHz of spectrum available by 2015 and 500 MHz available by the end of 2020, which would almost double the 547 MHz of spectrum currently available for wireless broadband use. The FCC plan includes auctioning up to 60 MHz of AWS spectrum, which includes the AWS-2 bands — 1915-1920 MHz paired with 1995-2000 MHz, and 2020-2025 MHz paired with 2175-2180 MHz — as well as the above-mentioned 1755-1780 MHz paired the AWS-3 band, 2155-2175 MHz.
Reallocating the 1755-1850 MHz block of frequencies is much more complicated than the FCC’s plan to free up 120 MHz of spectrum from television broadcasters through incentive actions. For example, the air combat training system is one of several DOD systems that presently reside in the 1755-1780 MHz band and can’t be moved within the 10-year timeframe, presenting a real obstacle to commercial use of this band. Another seemingly immovable object is the Space Ground Link Subsystem (SGLS), which provides control to DOD mission-critical spacecraft. Many such systems will continue to operate into the next decade, and some could remain active until 2045, requiring earth station sites and exclusion zones around these sites to mitigate interference in order to meet the 5-year goal.
Meanwhile, wireless carriers aren’t just waiting around to see if the FCC plan actually comes to fruition in time. Both Verizon Wireless and AT&T have been aggressively attempting to acquire larger shares of the existing spectrum. In late 2011, AT&T successfully bought 6 MHz of Qualcomm’s nationwide 700 MHz spectrum, and only recently ended its bid to buy T-Mobile, which was all about obtaining spectrum. The FCC is evaluating Verizon’s bid to acquire 122 20-MHz or 30-MHz AWS-1 licenses from SpectrumCo and 30 20-MHz AWS-1 licenses from Cox TMI Wireless.
In addition, the two mega-carriers are implementing new software technologies to squeeze more capacity out of their existing networks. Verizon’s solution will make streaming video more efficient by transmitting only the parts of a video frame that have changed significantly from the previous frame, thus reducing video traffic while still maintaining video quality. AT&T will implement software developed by Intucell that detects the overloading of a given cell and shrinks it, while simultaneously increasing the coverage of the neighboring cells to compensate for the overload cell. Field trials of this system reported a 15% drop in overloading and a 10% increase in speed.
Wireless carriers will surely continue to implement as many capacity utilization techniques as they can, including more complex MIMO technology, as it matures. However, these are no substitute for bandwidth. Given the difficulties associated with relocating systems from the 1755-1850 MHz band, it is hard for me to envision any new spectrum arriving from there in time to avert the bandwidth bottleneck the FCC foresees in 2014. It is more likely that spectrum from the broadcast incentive auctions will become available first — provided the FCC fast-tracks all the rule changes needed and the incumbent broadcasters cooperate. However, it looks increasingly like the demands of the data-hungry public will outpace the FCC’s best efforts to free up spectrum. If the carriers run out of band-aids before new spectrum arrives, we will all be waiting longer for something… our downloads.