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Frequently Asked Questions

Q: What is spectrum?

A: Spectrum describes the range of frequencies, which wireless devices can use to transmit and receive information. In order to manage access to spectrum, regulators allocate different bands of frequencies for different uses and establish technical rules minimize the likelihood of harmful interference. Some bands of spectrum are licensed for the exclusive use of certain entities and for specified purposes. These include uses as varied as military and public safety purposes as well as commercial applications such as radio, television and broadband Internet. Other bands are set aside for shared use on an unlicensed or license-exempt basis. Common uses of unlicensed or license-exempt spectrum are Wi-Fi networks and Bluetooth devices.

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Q: Is there a spectrum crunch?

A: No. As the number of wireless devices and the traffic that flows over them continues to grow, more efficient use of available spectrum is needed to keep up with the demand. In reality the so-called “spectrum crunch” reflects the artificial spectrum scarcity created by outmoded and inflexible regulations and network architectures that are not designed to accommodate today’s rapid pace of technical innovation and the resultant growth in the number of wireless devices and internet-based services. The underlying problem lies in an approach, which sees spectrum statically allocated to individual services (radio, television, etc.) even though the vast bulk of that spectrum isn’t used at any given place or time.

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Q: How can we solve this problem?

A: In order to address this issue, we need to transition to an approach in which spectrum is dynamically shared in response to local demand and usage models. Greater reliance on dynamic spectrum sharing approaches will lower barriers to market entry, leading to multiple solution providers to compete via innovation and price. Making underused spectrum available for dynamic sharing through a variety of licensing approaches will encourage further innovation and help resolve the perceived spectrum shortage.

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Q: What are the options for addressing increased demands for spectrum-based services?

A: Yes, policymakers have a variety of options for addressing the growing demand for spectrum-based services. In fact, there is no single solution that will act as a panacea. To meet growing demand and address other policy challenges, policy-makers must consider multiple approaches, such as reallocation, making more spectrum available on a non-exclusive unlicensed or license-exempt basis, auctioning and/or assigning more spectrum for exclusive use licenses, and innovative technologies, such as those which can be used in the TV band White Spaces that enable opportunistic, dynamic use of limited spectrum.

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Q: What is dynamic spectrum access?

A: Dynamic Spectrum Access (DSA) is an umbrella term used to describe a set of technologies and techniques enabling radio communications devices to opportunistically transmit on available radio spectrum. These technologies and techniques ensure that consumers and their devices have wireless bandwidth when and where they need it.

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Q: What are TV White Spaces?

A: The term TV White Space spectrum refers to frequencies in the VHF and UHF television broadcast bands that are either unassigned or unused by existing broadcast or other licensees. Television broadcasts occupy designated channels in the VHF and UHF bands, with the assignment of channels to broadcasts varying by location. Not all the designated channels are in use for broadcast in any given market, giving rise to “White Spaces” in which a channel that is not used for broadcast may be available for other purposes. Microsoft believes that the first globally-harmonized opportunity to use DSA technologies and techniques will be in the TV bands.

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Q: How do TV White Spaces relate to the spectrum crunch?

A: In every location around the world, there is unused TV band spectrum (essentially unused TV channels) that could be used for a range of wireless applications, from broadband, to wireless offload, to machine-to-machine. Leveraging dynamic spectrum access technologies, such as geolocation databases, this unused TV band spectrum could be put to good use. Unlocking the TV band and other unused white spaces spectrum will mean significantly increasing the total amount of available bandwidth available for consumers and their devices – and thereby alleviating pressure on other spectrum bands. Based on the results of trials we’ve conducted in the US, Europe, and Asia, we believe TVWS technology will be able to deliver similar functionality and speed compared to other wireless broadband technologies.

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Q: How do we know the use of White Spaces won’t interfere with licensed operations?

A: Microsoft has conducted trials and commercial pilots in Singapore, the U.S. and the U.K. and other companies have implemented similar solutions elsewhere. Our numerous tests have proved that TV band white space devices operate without causing interference to existing licensees entitled to interference protection.

White Spaces devices will gain managed access to unused TV channels by providing their precise locations to a database which in turn provides channel lists along with other operating parameters, such as power, duration, and geographic boundaries. White Space devices will only use those channels provided by an authorized White Space database. If no channels are returned, a White Spaces device will not transmit on TV band spectrum.

Please refer to the case study (pilots) section for more information.

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Q: What infrastructure would the technology require?

A: The one essential infrastructure piece needed to deploy a TV White Spaces network is a database. The database lets devices in the area know which spectrum is available for access in that location. Users will be able to purchase, install and operate their own networks. If a user would like to use TV White Spaces access points in a home or retail environment (e.g., to create a hot spot), a broadband connection is needed to access the network (either wireless or wired). To use TV White Spaces as a base-station complement, backhaul is needed (a high-capacity wire or wireless connection).

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Q: How far out in the future is implementation of this technology?

A: The technology has been tried and tested and therefore the implementation depends to a great extent on policymakers. Assuming appropriate regulations are put in place, consumers will in due course notice the introduction of devices, applications and services which will make use of White Spaces to deliver faster and better internet connections in many more places than they currently experience. Many industry observers believe 2013 will be a big year for TV White Spaces, with introduction of international standards and regulation in US, Canada, UK, Singapore and elsewhere.

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Q: What’s the benefit to consumers?

A: Consumers will benefit from higher bandwidth and/or more widely available network access, which will in turn enable them to enjoy the growing number of online services more fully and conveniently. This includes the full range of communications services, including the ability to send and receive audio-visual content. In addition, consumers will undoubtedly benefit from the economic growth that these new technologies would enable.

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Q: What work has been done so far on developing industry standards?

A: Various standards involving devices and databases are being developed. Most notable are efforts to standardize Wi-Fi – a proven and growing device ecosystem – for use in TV band and other White Space spectrum. The IEEE 802.11af task group is working on a global Wi-Fi standard for White Spaces access and a draft specification passed its second letter ballot in November 2012. Wi-Fi devices implementing the 802.11af standard will likely include multi-mode chips offering White Spaces (470-698 MHz), 2.4 GHz, and 5 GHz Wi-Fi connectivity. Other notable standards efforts are focused on addressing the emerging machine-to-machine family of use cases.

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Q: What changes need to occur to make widespread adoption of TVWS technology feasible?

A: The main change that needs to take place is legislative and regulatory. Policy-makers need to move away from predominantly promoting exclusive-use licensing and instead enable a variety of exclusive-use and non-exclusive spectrum access approaches across a variety of spectrum bands. To maximize efficiency, regulators should promote dynamic spectrum access techniques in spectrum made available on a non-exclusive basis. The first globally-harmonized opportunity to use dynamic spectrum access technologies and techniques will be in the TV bands. This approach will lower barriers to market entry and lead to multiple solution providers who compete via innovation and price.

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Q: What regulation is currently in place in the U.S. and elsewhere?

A: The United States and Finland are thus far the only countries to allow unlicensed access to the TV White Spaces. The U.S. Federal Communications Commission (FCC) recently began certifying White Space databases and devices and the first small-scale commercial networks are being deployed – in North Carolina and Virginia. Microsoft has received conditional authority from the U.S. FCC to serve as a White Space database administrator and must now go through a certification process.

The United Kingdom, Canada, and Singapore have commenced consultations. Japan and Korea are conducting large-scale trials and would benefit from having regulations in place when Wi-Fi standards are complete. Leveraging the transition from analog to digital television broadcasts, several other countries could develop regulations in the 2014-2015 timeframe.

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Q: What other bands should be opened to non-exclusive license-exempt use?

A: Although the first globally-harmonized opportunity to showcase DSA is occurring through license-exempt (unlicensed) access to the TV band White Spaces, DSA technologies and techniques can and will be used in a variety of regulatory settings, including licensed, lightly-licensed, and license-exempt access, and across a variety of spectrum bands, from sub-1 GHz all the way to the 5 GHz bands and above.

In its July 2012 report, the United States President’s Council of Advisors on Science and Technology (PCAST) recommends that in the next 1-3 years NTIA allow lower power “general authorized access” devices to operate in two federal bands, specifically 3550-3650 MHz and another band identified by the U.S. FCC and the NTIA. Ideally, the second band identified should be below 1 GHz. For example, two bands included on PCAST’s and NTIA’s list are 406.1-420 MHz and 1300­1370 MHz. There are likely others as well and we hope the work done at the Spectrum Observatory can help inform that discussion.

Opportunities are countless and spectrum sharing, especially unlicensed sharing in the bands below 2 GHz, represents a creative, tested and affordable way of extending broadband access. This technology can also support the efficient delivery of government services, such as real-time traffic monitoring and the management of government-operated infrastructure.

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Q: What efforts has Microsoft made to ensure the success of White Space technology?

A: Microsoft has spent many years investigating new technologies that can increase productive use of spectrum, through development of technology, trials and innovative solutions. For example, the Microsoft Spectrum Observatory was created with the purpose of providing an intuitive presentation of the usage of the wireless spectrum – allowing us to demonstrate that there is a lot of unused, but usable spectrum. The data we gather from the tool can better inform decisions regarding which spectrum bands are the most appropriate near term targets for expanded spectrum sharing.

We are committed to fostering the needed regulatory shifts that will make more under-utilized spectrum available. Our on-going trial project on our Redmond, Washington campus was one of the first TVWS-based trials to use an experimental license from the Federal Communications Commission in the US and covers the nearly 600-acre campus. Microsoft has also conducted and supported trials and commercial pilots in Singapore, the UK and the US.

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Q: What is Microsoft position when it comes to regulation?

A: We support ongoing efforts to gain a better understanding of spectrum use around the globe through deployment of Spectrum Observatories, trials and demonstrations.

We also support proposals to make the unused TV band spectrum available for license-exempt (unlicensed) access on a globally-harmonized basis, facilitated by the use of geolocation databases and other interference protection mechanisms.

We support enabling multiple competing database providers to encourage more intensive innovation in dynamic spectrum access and the businesses it can enable.

We support efforts to increase the availability of spectrum for license-exempt (unlicensed) use across a variety of frequencies – above and below 1 GHz.

We support regulations making other underused spectrum available for dynamic sharing in a variety of licensed, license-exempt (unlicensed), and lightly-licensed spectrum bands. In the long run, we support efforts to make spectrum sharing the default mode of use, with technical rules that address legitimate interference concerns.

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