The most useful way to distinguish pieces of radio spectrum used for wireless communications is simply asking whether they are licensed or unlicensed.
Licensed spectrum is leased from the government, which raises money through auctions. Unlicensed spectrum is free. That difference in cost has led to the two classes evolving very differently. The two have been trending toward each other, however. More accurately, mobile carriers, the main users of licensed spectrum, are looking with covetous eyes at less expensive unlicensed spectrum. In addition to being free, it can help solve the spectrum shortage that has grown as wireless has exploded.
Fierce Wireless reported yesterday that AT&T is considering the use of unlicensed spectrum to help fulfill its promise of providing 1 Gigabit per second (Gbps) LTE service. John Donovan, the chief strategy officer and group president for AT&T Technology and Operations, outlined the technologies the company will employ to reach the milestone speed. He said that Licensed Assisted Access (LAA), a technique that uses unlicensed spectrum, will be needed.
The need is not echoed by T-Mobile. Chief Technology Officer Neville Ray and Karri Kuoppamaki, the carrier’s vice president of Technology Development and Strategy, suggested that unlicensed spectrum was not a must. The company is looking at LAA, however.
Unlicensed spectrum is a hot topic. Multichannel News this week excerpted what is likely the final statement from Federal Communications Commission Commissioner Jessica Rosenworcel, who is unlikely to be re-nominated. She is a strong advocate of unlicensed spectrum:
I believe the future of spectrum policy requires a focus on not just licensed spectrum — but also unlicensed spectrum. Unlicensed spectrum — like WiFi — democratizes Internet access, encourages permission-less innovation in the Internet of Things, and contributes $140 billion in economic activity annually. This is good stuff.
Rosenworcel highlights various ways in which the FCC has pushed unlicensed spectrum.
It seems that the days of a hard line between licensed and unlicensed spectrum will fade. Wireless Broadband Alliance CEO Shrikant Shenwai suggested late last year at WirelessWeek that things with licensed and unlicensed spectrum will change drastically:
Coexistence and full convergence will go far beyond what we are seeing today where mobile operators offload data to Wi-Fi, or fixed-line operators access licensed spectrum through MVNO deals. In fact, alternatives are already appearing to the traditional options of a long-term spectrum license acquired at auction, or completely unlicensed bands in which anybody can operate. New options which can support more flexible use of different spectrum include shared access, light and short-term licenses, and dynamic access on an on-demand basis.
Of course, the pace of change will be influenced by the version of the FCC put in place by the Trump administration.
The melding of licensed and unlicensed spectrum is an important issue. Shenwai concludes his post by saying that some of the services and advances being widely promised today, such as 5G, the Internet of Things (IoT) and smart cities, won’t be economic or practical without this merging. Whether or not that is overstating the case is uncertain, of course. But what is clear is that removing the artificial lines between the two approaches will expedite progress.
Carl Weinschenk covers telecom for IT Business Edge. He writes about wireless technology, disaster recovery/business continuity, cellular services, the Internet of Things, machine-to-machine communications and other emerging technologies and platforms. He also covers net neutrality and related regulatory issues. Weinschenk has written about the phone companies, cable operators and related companies for decades and is senior editor of Broadband Technology Report. He can be reached at firstname.lastname@example.org and via twitter at @DailyMusicBrk.