White spaces: the next frontier or overhyped?

White spaces: the next frontier or overhyped?

The Delta Perspective

1. Introduction: the impetus

The mobile data explosion of recent years has significantly increased the network capacity requirements for operators including the spectrum capacity. More spectrum has been and is being made available across markets. The majority of this new spectrum, however, typically falls under telecom regulation and is, as a consequence, mostly licensed.
An increasing interest exists amongst the different players in the TMT value chain to use unlicensed spectrum, including bands used for Wi-Fi, microwaves, small electronics, and guard bands or white spaces.
2. The unlocked spectrum potential of white spaces
White spaces have been given different names: Google founder Larry Page calls it “WiFi on steroids”, Microsoft calls it “White fi”, while Gartner changed the name of white space in its Hype Cycle to Super Wi-Fi. Irrespective of its name, a white space is a frequency band allocated to a broadcasting service which is not in use by the designated service, i.e. Digital TV.
Many countries have engaged or are expected to engage in the Digital Switchover, the process by which television broadcasting is switching from analog to digital. Considering that digital television broadcasting is more spectrum efficient compared to analog, this transition has freed up spectrum, mostly in the UHF band. This has resulted in 2 major developments:


  • Interleaved frequency bands or white spaces were created to ensure that the TV frequency bands don’t interfere; and Significant spectrum has been cleared and became available for other services, also called the Digital Dividend (see Delta Partners White Paper: The Digital Dividend in Europe: in the eye of “The Perfect Storm”).
  • As shown in Exhibit 1, while the Digital Dividend plays in the 790 MHz to 862 MHz band, white spaces are present in the 470 MHz to 790 MHz band and thus offer attractive spectrum bands for broadband services.

Exhibit 1

White space exploitation is moving ahead, by regulators and vendors, not necessarily by operators
The FCC (United States regulator) has projected a spectrum deficiency at current mobile data take-up rates. As a result, President Obama, through a Presidential Memorandum released in June 2013, urged for greater spectrum sharing (between government agencies and the private sector) and announced additional Federal investments of $100 million in spectrum sharing and advanced communications, including database enabled sharing (utilized by white spaces)1.
Similar conclusions have been made by Ofcom, the UK regulator. Both regulators have urged for a radical increase in broadband spectrum and have kicked off the start of the white space broadband development or Super Wi-Fi.

4. Super Wifi as a technical solution

The telecom industry is increasingly backing up the technological developments of white space broadband services. Both LTE and Wi-Fi like white space technologies are being developed. The IEEE has engaged in the development of the next-generation WiFi 802.22 standard which will work on the white space frequencies and is said to enable data transfer up to a 100 kilometers at 22Mbps. Huawei has launched trials for white space LTE TDD technologies and the 3GPP organization is integrating unlicensed spectrum technologies in its releases of the Generic Access Network.
In addition, there have been several key trials being pushed by regulators. For example, in the first quarter of 2013, the FCC authorized white spaces database administrators (e.g. Google and Key Bridge) to provide nationwide public trials for devices in white spaces2. These database managers are now authorized to track geographical white space frequency availability and offer this data to all devices trying to connect, while preventing interference to authorized use by broadcast TV stations.
Similarly, in November 2012, Ofcom launched a proposal and consultation for a framework to allow white spaces spectrum to be utilized by consumer devices3. The regulator aims at launching a pilot to use white space technology in 2013 involving the operation of white space devices, databases and processes to mitigate interference with potential full rollout of the technology in 20144. Similar to the U.S. and the U.K., other countries such as Singapore and Canada have also shown interest in these white spaces by launching public consultations and trials to investigate the feasibility for white space broadband services. For example, in 2012, Singapore launched three commercial pilots including 1) wireless connectivity and smart sensors in a golf course, 2) marine Wi-Fi (as an alternative to satellite based internet for its transit ships), and 3) smart grid applications (in a university to meter the use of air-conditioners)5.

5. So is Super WiFi the next frontier? Not so fast.

Although there are clear advantages for both mobile operators and OTT players aiming at making inroads in the connectivity business, the future of white space broadband services will depend on overcoming current and potential future hurdles. For example:
  • Potential licensing: The successful mass adoption of white space spectrum assumes a regulatory environment where this spectrum can be used “for free” similar to the USA. Several reasons might drive white space towards a licensed eco-system:
  • Unlicensed spectrum does not generate income to governments, nor can the regulator dictate the condition on the spectrum use (for example, coverage requirements in areas not financially feasible)
  • Licensing drives standardization, something that has proven to be the tipping point of success (example, GSM, 3GGP)
  • Licensing allows for better coordination and interference management. Similar approaches in the past (e.g., LightSquared) have failed due to lack of coordination of spectrum and interference issues with legacy systems\
  • Further technical development required: Commercialization of white space broadband services will require further technical development. Specifically, considering that no interference can be allowed between the digital TV broadcasting and the unlicensed spectrum broadband services, Super Wi-Fi will need cognitive radio systems.  This implies that devices will need to adapt to available frequency bands based on geographical location to avoid interference with TV broadcasters.
  • Device ecosystem: The device eco-system for white space spectrum is underdeveloped. For example, in the US, the FCC has approved one device, a radio transmitter from KTS Wireless, for unlicensed use in white spaces6. While we can expect devices from members of the White Space Coalition, which includes Microsoft, Google, Dell, HP, and Samsung, it will take time for devices to be launched and reach critical mass for commercial adoption.
  • LTE integration: The unlicensed spectrum integration in the 3GPP frameworks has not yet materialized and adoption of the Generic Access Network standards is yet to happen.

6. Conclusion: the so what for MNOs to embrace the attack?

With the launch of Super Wi-Fi pilots and white spaces based broadband increasingly being discussed and developed, operators still have some time to think and act. Indeed, Gartner’s hype cycle suggests it would take five years or more for Super Wi-Fi to achieve mainstream adoption. While the technological and regulatory environment for white space spectrum evolves, operators can start to proactively track the progress of this technology and potentially influence the development. The technology seems to be a promising last-mile and backhaul alternative and operators should not overlook the competitive disruptive nature when this technology matures and the spectrum remains unlicensed.
In the short to mid-term future, operators could potentially start to extend LTE service in the 700 MHz white space band or use Super Wi-Fi to offload traffic in cities. In doing so, operators could defend against OTT players trying to enter the access business and avoid being caught by surprise (similar to the success of other OTT apps like Skype and Whatsapp).
1 Fact Sheet: Administration provides another boost to Wireless Broadband and Technological Innovation (June 2013); “Four years of broadband growth,” Office of Science and Technology Policy & The National Economic Council (June 2013). Other types of sharing include Temporal Sharing (time based), Geographic Sharing, and Dynamic Sensing.
3 Ofcom (Office of Communications) – www.ofcom.org.uk