Cognitive Radio: A Solution for the Spectrum Shortage?
Hence the growing appeal of cognitive radio, which would enable regulators worldwide to shoehorn more services into existing spectrum, such as cellular into bands that are today the exclusive domain of government agencies. Cognitive radios change frequencies, modulation schemes and other parameters under the control of spectrum databases, radio frequency (RF) sensing technology or both. Regardless of how they're controlled, the goal of cognitive radios is to find temporary, often fleeting vacancies around other users.
If the technology lives up to its billing, it would be a miracle of efficiency not seen since Jesus fed thousands with five loaves of bread and two fish. "Cognitive radio is an essential technology to achieving full spectrum utilization, which is now estimated to be only 20 percent utilized," says Peter Flynn, Texas Instruments Inc. (NYSE: TXN) product and program manager for multicore growth markets.
Cognitive radio isn't a new concept. In fact, Bluetooth is an example of an existing cognitive radio application. What's changed is that regulators increasingly see it as a viable option for freeing up spectrum faster and more cost-effectively than traditional methods such as auctions. That's one key finding in the new Heavy Reading 4G/LTE Insider, "Cognitive Radio for LTE & Beyond."
Case in point: The U.S. President's Council of Advisors on Science and Technology (PCAST) said in a July 2012 report (PDF), "The norm for spectrum use should be sharing, not exclusivity." Now it's up to vendors and regulators to convince cellular operators, government agencies and other spectrum licensees that sharing benefits everyone. It won't be easy or happen overnight.
One hurdle is cellular operators' reluctance to use spectrum to which they don't have exclusive rights. That's ironic, considering how many use shared spectrum at 5 GHz for cell-site backhaul, as well as Wi-Fi offload. Yet many vendors believe – rightly so – that operators will embrace cognitive radio for TV white spaces and other bands when they run out of alternatives.
"I think they'll get over it when they start to know they need to do something other than Wi-Fi offload," says Tod Sizer, head of wireless research at Alcatel-Lucent's Bell Labs and inventor of the lightRadio cube. "It's a matter of time."
That sense of inevitability is one reason why the cognitive radio vendor ecosystem is relatively large for such a nascent space. However, cellular operators aren't the only potential buyers of cognitive radios. Public safety, the military, utility companies – particularly for smart grid applications – security/alarm companies, content providers such as Netflix and IT companies such as Apple Inc. (Nasdaq: AAPL) and Google (Nasdaq: GOOG) are other members of the addressable market. Some of them are interested because they don't own spectrum or can't afford to acquire it.
"They seem to be much more of the mindset of using shared spectrum and cognitive radio," says Rick Rotondo, xG Technology Inc. VP of marketing. "Carriers will not necessarily be the early adopters of cognitive radio and shared spectrum."
— Tim Kridel, Contributing Analyst, 4G/LTE Insider
This report,"Cognitive Radio for LTE & Beyond," is available as part of an annual subscription (6 issues per year) to Heavy Reading 4G/LTE Insider, priced at $1,595. Individual reports are available for $900. To subscribe, please visit: www.heavyreading.com/4glte.