White space (telecommunications)
Encyclopedia
In telecommunications, white spaces refer to frequencies
allocated to a broadcasting
service but not used locally.
process creates a bandplan
, which for technical reasons assigns white space between used radio bands or channel
s to avoid interference
. In this case, while the frequencies are unused, they have been specifically assigned for a purpose, such as a guard band
. Most commonly however, these white spaces exist naturally between used channels, since assigning nearby transmissions to immediately adjacent channel
s will cause destructive interference to both.
In addition to white space assigned for technical reasons, there is also unused radio spectrum
which has either never been used, or is becoming free as a result of technical changes. In particular, the switchover to digital television
frees up large areas between about 50 MHz and 700 MHz. This is because digital transmissions can be packed into adjacent channels, while analog ones cannot. This means that the band can be "compressed" into fewer channels, while still allowing for more transmissions.
In the United States, the abandoned television frequencies are primarily in the upper UHF "700-megahertz" band, covering TV channels 52 to 69 (698 to 806 MHz). U.S. television and its white spaces will continue to exist in UHF frequencies, as well as VHF frequencies for which mobile users and white-space devices require larger antennas. In the rest of the world, the abandoned television channels are VHF, and the resulting large VHF white spaces are being reallocated for the worldwide (except the U.S.) digital radio
standard DAB
and DAB+, and DMB
.
and those from the White Spaces Coalition, have advocated using white spaces left by the termination of analog TV to provide wireless broadband Internet access
. However, these efforts may impact wireless microphone
s, medical telemetry
, and other technologies that have historically relied on these open frequencies.
A device intended to use these available channels is a "white-spaces device" (WSD). These are designed to detect the presence of existing signals, such as TV stations and other wireless users, and to then avoid the use of these channels. Early ideas proposed including GPS receivers and programming each WSD with a database
of all TV stations in an area, however this would not have avoided other non-stationary or unlicensed users in the area, or any stations licensed or altered after the device was made.
broadcasts, which operated between the 54 MHz and 806 MHz (54-72,76-88,174-216,470-608,and 614-806) television frequencies (Channels 2-69), ceased operating on June 12, 2009 per a United States digital switchover mandate. At that time, full power TV stations were required to switch to digital transmission and operate only between 54-698 MHz. This is also the timetable that the white space coalition has set to begin offering wireless broadband services to consumers. The delay allows time for the United States Federal Communications Commission
(FCC) to test the technology and make sure that it does not interfere with existing television broadcasts. Similar technologies could be used worldwide as much of the core technology is already in place.
Theatrical producer
s and sports franchises hoped to derail or delay the decision, arguing that their own transmissions — whether from television signals or from wireless microphones used in live music performances — could face interference from new devices that use the white spaces. However, the FCC rejected their arguments, saying enough testing has been done, and through new regulations, possible interference will be minimized.
More of the broadcast spectrum was needed for wireless broadband Internet access, and in March 2009, Massachusetts Senator John Kerry
introduced a bill requiring a study of efficient use of the spectrum. Academics have studied the matter and have promoted the idea of using computing technology to capture the benefits of the white space.
, Google
, Dell
, HP, Intel, Philips
, Earthlink
, and Samsung Electro-Mechanics.
The White Spaces Coalition was formed after the Senate set the date to cease analog broadcasts. It doesn't appear to have a website, but many of the companies involved in the White Spaces Coalition are also involved in the Wireless Innovation Alliance.
Google
sponsored a campaign named Free the Airwaves with the purpose of switching over the white spaces that will be cleared up in 2009 by the DTV conversion process by the FCC and converted to an un-licensed spectrum that can be used by Wi-Fi
devices. The National Association of Broadcasters
disapproves of the project because they claim that it would reduce the broadcast quality of their TV signals.
However, on August 13, 2007 Microsoft filed a document with the FCC in which it described a meeting that its engineers had with FCC engineers from the Office of Engineering and Technology on August 9 and 10. At this meeting the Microsoft engineers showed results from their testing done with identical prototype devices and using identical testing methods that "detected DTV signals
at a threshold of -114 dBm
in laboratory bench testing with 100 percent accuracy, performing exactly as expected." In the presence of FCC engineers, the Microsoft engineers took apart the device that the FCC had tested to find the cause of the poor performance. They found that "the scanner in the device had been damaged and operated at a severely degraded level" which explained the FCC unit's inability to detect when channels were occupied. It was also pointed out that the FCC was in possession of an identical backup prototype that was in perfect operating condition that they had not tested.
On November 4, 2008, the FCC voted 5-0 to approve the unlicensed use of white space, thereby silencing opposition from broadcasters. The actual Second Report and Order was released ten days later and contains some serious obstacles for the development and use of TV Band Devices as they are called by FCC. Devices must both consult an FCC-mandated database to determine which channels are available for use at a given location, and must also monitor the spectrum locally once every minute to confirm that no legacy wireless microphones, video assist devices or other emitters are present. If a single transmission is detected, the device may not transmit anywhere within the entire 6 MHz channel in which the transmission was received. It is hoped that, within a year, this new access will lead to more reliable WiFi
and other technologies.
On September 23, 2010 the FCC released a Memorandum Opinion and Order that determined the final rules for the use of white space for unlicensed wireless devices. The new rules removed mandatory sensing requirements which greatly facilitates the use of the spectrum with geolocation based channel allocation. The final rules adopt a proposal from the White Spaces Coalition for very strict emission rules that prevent the direct use of IEEE 802.11 (Wi-Fi) in a single channel effectively making the new spectrum unusable for Wi-Fi technologies.
(NAB) and the Association for Maximum Service Television, Inc. (MSTV) asked a Federal court to shut down the FCC's authorization of white space wireless devices. The plaintiffs allege that portable, unlicensed personal devices operating in the same band as TV broadcasts have been "proven" to cause interference despite FCC tests to the contrary. The lawsuit was filed in a United States Court of Appeals for the District of Columbia Circuit. The Petition for Review states that the FCC's decision to allow white space personal devices "will have a direct adverse impact" on MSTV's and NAB's members, and that the Commission's decision is "arbitrary, capricious, and otherwise not in accordance with law.". A Motion to Govern the case is due to be considered on February 7, 2011.
, which was the test market for the DTV transition, unveiled a new municipal wireless network, after a month of testing. The network will use the white spaces made available by the end of analog TV. Spectrum Bridge will work to make sure TV stations in the market do not receive interference ("no interference issues" have been reported), and the company hopes to do the same if similar service becomes nationwide. The "smart city" network will not compete with cell phone companies but will instead be used for "national purposes", including government and energy monitoring. TV Band Service, made up of private investors, has put up cameras in parks, and along highways to show traffic. Other uses include water level and quality, turning off lights in ball parks, and public Wi-Fi in certain areas. TV Band has an 18-month experimental license.
, BSkyB, the BBC
, and BT
, with the actual network hardware being provided by Neul. In the demonstration, the Adaptrum whitespace system provided the broadband IP connectivity allowing a client-side Microsoft Xbox
to stream live HD videos from the Internet. Also as part of the demo, a live Xbox/Kinect video chat was established between two Xbox/Kinect units connected through the same TV whitespace connection. These applications were demonstrated under a highly challenging radio propagation environment with more than 120 dB link loss through buildings, foliage, walls, furniture, people etc. and with severe multipath effects.
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
allocated to a broadcasting
Broadcasting
Broadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...
service but not used locally.
Summary
National and international bodies assign different frequencies for specific uses, and in most cases license the rights to broadcast over these frequencies. This frequency allocationFrequency allocation
Use of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Radio propagation does not stop at national boundaries...
process creates a bandplan
Bandplan
A bandplan or band plan is a plan for using a particular band of radio frequencies, that are a portion of the electromagnetic spectrum . Each bandplan defines the frequency range to be included, how channels are to be defined, and what will be carried on those channels...
, which for technical reasons assigns white space between used radio bands or channel
Channel (communications)
In telecommunications and computer networking, a communication channel, or channel, refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel...
s to avoid interference
Interference (communication)
In communications and electronics, especially in telecommunications, interference is anything which alters, modifies, or disrupts a signal as it travels along a channel between a source and a receiver. The term typically refers to the addition of unwanted signals to a useful signal...
. In this case, while the frequencies are unused, they have been specifically assigned for a purpose, such as a guard band
Guard band
-Radio and electronic signalling:In radio, a guard band is an unused part of the radio spectrum between radio bands, for the purpose of preventing interference....
. Most commonly however, these white spaces exist naturally between used channels, since assigning nearby transmissions to immediately adjacent channel
Adjacent channel
In broadcasting an adjacent channel is an AM, FM, or TV channel that is next to another channel. First-adjacent is immediately next to another channel, second-adjacent is two channels away, and so forth. Information on adjacent channels is used in keeping stations from interfering with one...
s will cause destructive interference to both.
In addition to white space assigned for technical reasons, there is also unused radio spectrum
Radio spectrum
Radio spectrum refers to the part of the electromagnetic spectrum corresponding to radio frequencies – that is, frequencies lower than around 300 GHz ....
which has either never been used, or is becoming free as a result of technical changes. In particular, the switchover to digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...
frees up large areas between about 50 MHz and 700 MHz. This is because digital transmissions can be packed into adjacent channels, while analog ones cannot. This means that the band can be "compressed" into fewer channels, while still allowing for more transmissions.
In the United States, the abandoned television frequencies are primarily in the upper UHF "700-megahertz" band, covering TV channels 52 to 69 (698 to 806 MHz). U.S. television and its white spaces will continue to exist in UHF frequencies, as well as VHF frequencies for which mobile users and white-space devices require larger antennas. In the rest of the world, the abandoned television channels are VHF, and the resulting large VHF white spaces are being reallocated for the worldwide (except the U.S.) digital radio
Digital radio
Digital radio has several meanings:1. Today the most common meaning is digital radio broadcasting technologies, such as the digital audio broadcasting system, also known as Eureka 147. In these systems, the analog audio signal is digitized into zeros and ones, compressed using formats such as...
standard DAB
Digital audio broadcasting
Digital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....
and DAB+, and DMB
Digital Multimedia Broadcasting
Digital Multimedia Broadcasting is a digital radio transmission technology developed in South Korea as part of the national IT project for sending multimedia such as TV, radio and datacasting to mobile devices such as mobile phones...
.
White-spaces devices
Various proposals, including IEEE 802.11af, IEEE 802.22IEEE 802.22
IEEE 802.22 is a standard for Wireless Regional Area Network using white spaces in the TV frequency spectrum. The development of the IEEE 802.22 WRAN standard is aimed at using cognitive radio techniques to allow sharing of geographically unused spectrum allocated to the Television Broadcast...
and those from the White Spaces Coalition, have advocated using white spaces left by the termination of analog TV to provide wireless broadband Internet access
Internet access
Many technologies and service plans for Internet access allow customers to connect to the Internet.Consumer use first became popular through dial-up connections in the 20th century....
. However, these efforts may impact wireless microphone
Wireless microphone
A wireless microphone, as the name implies, is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated...
s, medical telemetry
Telemetry
Telemetry is a technology that allows measurements to be made at a distance, usually via radio wave transmission and reception of the information. The word is derived from Greek roots: tele = remote, and metron = measure...
, and other technologies that have historically relied on these open frequencies.
A device intended to use these available channels is a "white-spaces device" (WSD). These are designed to detect the presence of existing signals, such as TV stations and other wireless users, and to then avoid the use of these channels. Early ideas proposed including GPS receivers and programming each WSD with a database
Database
A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality , in a way that supports processes requiring this information...
of all TV stations in an area, however this would not have avoided other non-stationary or unlicensed users in the area, or any stations licensed or altered after the device was made.
United States
Full power analog televisionAnalog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...
broadcasts, which operated between the 54 MHz and 806 MHz (54-72,76-88,174-216,470-608,and 614-806) television frequencies (Channels 2-69), ceased operating on June 12, 2009 per a United States digital switchover mandate. At that time, full power TV stations were required to switch to digital transmission and operate only between 54-698 MHz. This is also the timetable that the white space coalition has set to begin offering wireless broadband services to consumers. The delay allows time for the United States Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
(FCC) to test the technology and make sure that it does not interfere with existing television broadcasts. Similar technologies could be used worldwide as much of the core technology is already in place.
Theatrical producer
Theatrical producer
A theatrical producer is the person ultimately responsible for overseeing all aspects of mounting a theatre production. The independent producer will usually be the originator and finder of the script and starts the whole process...
s and sports franchises hoped to derail or delay the decision, arguing that their own transmissions — whether from television signals or from wireless microphones used in live music performances — could face interference from new devices that use the white spaces. However, the FCC rejected their arguments, saying enough testing has been done, and through new regulations, possible interference will be minimized.
More of the broadcast spectrum was needed for wireless broadband Internet access, and in March 2009, Massachusetts Senator John Kerry
John Kerry
John Forbes Kerry is the senior United States Senator from Massachusetts, the 10th most senior U.S. Senator and chairman of the Senate Foreign Relations Committee. He was the presidential nominee of the Democratic Party in the 2004 presidential election, but lost to former President George W...
introduced a bill requiring a study of efficient use of the spectrum. Academics have studied the matter and have promoted the idea of using computing technology to capture the benefits of the white space.
White Spaces Coalition
The White Spaces Coalition consists of eight large technology companies that planned to deliver high speed internet access beginning in February 2009 to United States consumers via existing "white space" in unused television frequencies between 54-698 MHz (TV Channels 2-51). The coalition expected speeds of 80 Mbps and above, and 400 to 800 Mbit/s for white space short-range networking. The group includes MicrosoftMicrosoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
Google
Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
, Dell
Dell
Dell, Inc. is an American multinational information technology corporation based in 1 Dell Way, Round Rock, Texas, United States, that develops, sells and supports computers and related products and services. Bearing the name of its founder, Michael Dell, the company is one of the largest...
, HP, Intel, Philips
Philips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
, Earthlink
EarthLink
EarthLink , is an Internet service provider headquartered in Atlanta, Georgia, USA. It claims 1.94 million subscribers.- Business :EarthLink provides a variety of Internet connection types, including dial-up, DSL, satellite, and cable. Both dial-up and high speed Internet access are available...
, and Samsung Electro-Mechanics.
The White Spaces Coalition was formed after the Senate set the date to cease analog broadcasts. It doesn't appear to have a website, but many of the companies involved in the White Spaces Coalition are also involved in the Wireless Innovation Alliance.
Google
Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
sponsored a campaign named Free the Airwaves with the purpose of switching over the white spaces that will be cleared up in 2009 by the DTV conversion process by the FCC and converted to an un-licensed spectrum that can be used by Wi-Fi
Wi-Fi
Wi-Fi or Wifi, is a mechanism for wirelessly connecting electronic devices. A device enabled with Wi-Fi, such as a personal computer, video game console, smartphone, or digital audio player, can connect to the Internet via a wireless network access point. An access point has a range of about 20...
devices. The National Association of Broadcasters
National Association of Broadcasters
The National Association of Broadcasters is a trade association, workers union, and lobby group representing the interests of for-profit, over-the-air radio and television broadcasters in the United States...
disapproves of the project because they claim that it would reduce the broadcast quality of their TV signals.
Preliminary test
The Federal Communications Commission's Office of Engineering and Technology released a report dated July 31, 2007 with results from its investigation of two preliminary devices submitted. The report concluded that the devices did not reliably sense the presence of television transmissions or other incumbent users, hence are not acceptable for use in their current state and no further testing was deemed necessary.However, on August 13, 2007 Microsoft filed a document with the FCC in which it described a meeting that its engineers had with FCC engineers from the Office of Engineering and Technology on August 9 and 10. At this meeting the Microsoft engineers showed results from their testing done with identical prototype devices and using identical testing methods that "detected DTV signals
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...
at a threshold of -114 dBm
DBm
dBm is an abbreviation for the power ratio in decibels of the measured power referenced to one milliwatt . It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form...
in laboratory bench testing with 100 percent accuracy, performing exactly as expected." In the presence of FCC engineers, the Microsoft engineers took apart the device that the FCC had tested to find the cause of the poor performance. They found that "the scanner in the device had been damaged and operated at a severely degraded level" which explained the FCC unit's inability to detect when channels were occupied. It was also pointed out that the FCC was in possession of an identical backup prototype that was in perfect operating condition that they had not tested.
FCC decision
TV broadcasters and other incumbent users of this spectrum (both licensed and unlicensed, including makers of wireless audio systems) feared that their systems would no longer function properly if unlicensed devices were to operate in the same spectrum. However, the FCC's Office of Engineering and Technology released a report dated October 15, 2008, which evaluated prototype TV-band white spaces devices submitted by Adaptrum, The Institute for Infocomm Research, Motorola and Philips. The report concluded that these devices had met the burden of "proof of concept" in their ability to detect and avoid legacy transmissions, although none of the tested devices adequately detected wireless microphone signals in the presence of a digital TV transmitter on an adjacent channel.On November 4, 2008, the FCC voted 5-0 to approve the unlicensed use of white space, thereby silencing opposition from broadcasters. The actual Second Report and Order was released ten days later and contains some serious obstacles for the development and use of TV Band Devices as they are called by FCC. Devices must both consult an FCC-mandated database to determine which channels are available for use at a given location, and must also monitor the spectrum locally once every minute to confirm that no legacy wireless microphones, video assist devices or other emitters are present. If a single transmission is detected, the device may not transmit anywhere within the entire 6 MHz channel in which the transmission was received. It is hoped that, within a year, this new access will lead to more reliable WiFi
WIFI
WIFI is a radio station broadcasting a brokered format. Licensed to Florence, New Jersey, USA, the station is currently operated by Florence Broadcasting Partners, LLC.This station was previously owned by Real Life Broadcasting...
and other technologies.
On September 23, 2010 the FCC released a Memorandum Opinion and Order that determined the final rules for the use of white space for unlicensed wireless devices. The new rules removed mandatory sensing requirements which greatly facilitates the use of the spectrum with geolocation based channel allocation. The final rules adopt a proposal from the White Spaces Coalition for very strict emission rules that prevent the direct use of IEEE 802.11 (Wi-Fi) in a single channel effectively making the new spectrum unusable for Wi-Fi technologies.
Broadcaster lawsuit
On February 27, 2009, the National Association of BroadcastersNational Association of Broadcasters
The National Association of Broadcasters is a trade association, workers union, and lobby group representing the interests of for-profit, over-the-air radio and television broadcasters in the United States...
(NAB) and the Association for Maximum Service Television, Inc. (MSTV) asked a Federal court to shut down the FCC's authorization of white space wireless devices. The plaintiffs allege that portable, unlicensed personal devices operating in the same band as TV broadcasts have been "proven" to cause interference despite FCC tests to the contrary. The lawsuit was filed in a United States Court of Appeals for the District of Columbia Circuit. The Petition for Review states that the FCC's decision to allow white space personal devices "will have a direct adverse impact" on MSTV's and NAB's members, and that the Commission's decision is "arbitrary, capricious, and otherwise not in accordance with law.". A Motion to Govern the case is due to be considered on February 7, 2011.
Wilmington, North Carolina tests
On February 24, 2010, officials in Wilmington, North CarolinaWilmington, North Carolina
Wilmington is a port city in and is the county seat of New Hanover County, North Carolina, United States. The population is 106,476 according to the 2010 Census, making it the eighth most populous city in the state of North Carolina...
, which was the test market for the DTV transition, unveiled a new municipal wireless network, after a month of testing. The network will use the white spaces made available by the end of analog TV. Spectrum Bridge will work to make sure TV stations in the market do not receive interference ("no interference issues" have been reported), and the company hopes to do the same if similar service becomes nationwide. The "smart city" network will not compete with cell phone companies but will instead be used for "national purposes", including government and energy monitoring. TV Band Service, made up of private investors, has put up cameras in parks, and along highways to show traffic. Other uses include water level and quality, turning off lights in ball parks, and public Wi-Fi in certain areas. TV Band has an 18-month experimental license.
Cambridge, United Kingdom tests
On June 29, 2011, One of the largest commercial tests of white space Wi-Fi was conducted in Cambridge, England. The trial was conducted by Microsoft using technology developed by Adaptrum and backed by a consortium of ISP's and tech companies including NokiaNokia
Nokia Corporation is a Finnish multinational communications corporation that is headquartered in Keilaniemi, Espoo, a city neighbouring Finland's capital Helsinki...
, BSkyB, the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
, and BT
BT
BT may stand for:* Baal teshuva, a Jew who became Orthodox * Babylonian Talmud, a central text in Judaism* Bacillus thuringiensis, a bacterium which forms Bt toxins...
, with the actual network hardware being provided by Neul. In the demonstration, the Adaptrum whitespace system provided the broadband IP connectivity allowing a client-side Microsoft Xbox
Xbox
The Xbox is a sixth-generation video game console manufactured by Microsoft. It was released on November 15, 2001 in North America, February 22, 2002 in Japan, and March 14, 2002 in Australia and Europe and is the predecessor to the Xbox 360. It was Microsoft's first foray into the gaming console...
to stream live HD videos from the Internet. Also as part of the demo, a live Xbox/Kinect video chat was established between two Xbox/Kinect units connected through the same TV whitespace connection. These applications were demonstrated under a highly challenging radio propagation environment with more than 120 dB link loss through buildings, foliage, walls, furniture, people etc. and with severe multipath effects.
See also
- United States 2008 wireless spectrum auctionUnited States 2008 wireless spectrum auctionThe United States 700 MHz FCC wireless spectrum auction, officially known as Auction 73, was started by the Federal Communications Commission on January 24, 2008 for the rights to operate the 700 MHz frequency band in the United States...
- IEEE 802.22IEEE 802.22IEEE 802.22 is a standard for Wireless Regional Area Network using white spaces in the TV frequency spectrum. The development of the IEEE 802.22 WRAN standard is aimed at using cognitive radio techniques to allow sharing of geographically unused spectrum allocated to the Television Broadcast...
- IEEE 1900.7 working group -Radio Interface for White Space Dynamic Spectrum Access Radio Systems Supporting Fixed and Mobile Operation
External links
- http://news.com.com/Why+dont+we+just+auction+the+white+space/2010-1036_3-6072534.html
- http://www.dailywireless.org/2007/01/11/white-space-act-up/
- http://www.hightechforum.org/wi-fi-on-crutches/
- http://cyberlaw.stanford.edu/node/5262
- http://www.cs.uc.edu/~cordeicm/papers/jcm06.pdf
- http://www.dailywireless.org/2008/08/08/motorola-on-white-spaces-were-good/
- FCC OKs White Spaces Boston Globe, Nov 4, 2008
- Nov. 4 2008: FCC Passes White Spaces
- White Spaces War Heats Up at FCC, October 4, 2007
- Google Plan Would Open TV Band for Wireless Use, New York Times, March 25, 2008
- The Economist: Wireless at Warp Speed - Nov 7, 2008
- Areas for TV whitespace standardization - IEEE presentation on possible wireless standards for TV white space
- http://www.fcc.gov/Daily_Releases/Daily_Business/2011/db0126/DA-11-131A1.pdf - FCC announces the White Spaces Devices database administrators
- FCC Promoting More Efficient Use of Spectrum Through Dynamic Spectrum Use Technologies