Federal Communications Commission FCC 08-260 
Before the 
Federal Communications Commission 
Washington, D.C. 20554 
In the Matter of 
Unlicensed Operation in the TV Broadcast Bands 
Additional Spectrum for Unlicensed Devices 
Below 900 MHz and in the 3 GHz Band 
)))))) 
ET Docket No. 04-186 
ET Docket No. 02-380 
SECOND REPORT AND ORDER AND 
MEMORANDUM OPINION AND ORDER 
Adopted: November 4, 2008 Released: November 14, 2008 
By the Commission: Chairman Martin, and Commissioners Copps, Adelstein, and McDowell issuing 
separate statements; Commissioner Tate approving in part, dissenting in part and issuing a statement. 
TABLE OF CONTENTS 
Paragraph 
I. EXECUTIVE SUMMARY.................................................................................................................... 1 
II INTRODUCTION................................................................................................................................. 2 
III. BACKGROUND................................................................................................................................. 11 
IV. DISCUSSION...................................................................................................................................... 32 
A. Licensed Vs. Unlicensed Operation............................................................................................... 35 
B. Plan For Unlicensed Use Of The TV Bands .................................................................................. 52 
1. Methods For Determining Occupied And Unoccupied Channels ........................................... 55 
2. Fixed Devices .......................................................................................................................... 99 
3. Personal/Portable Devices ..................................................................................................... 116 
C. Permissible Channels For Unlicensed Operation......................................................................... 137 
D. Protection Of Broadcast Television And Other Services............................................................. 158 
E. TV Bands Database System Requirements.................................................................................. 201 
F. Technical Requirements............................................................................................................... 225 
1. Transmit Antenna Height Limits........................................................................................... 226 
2. Transmit Power Control ........................................................................................................ 230 
3. Out-Of-Band Emissions Limits............................................................................................. 233 
4. Spectrum Sensing .................................................................................................................. 237 
5. Measurement Procedures....................................................................................................... 251 
6. Spectrum Sharing .................................................................................................................. 253 
G. Equipment Certification Required ............................................................................................... 256 
H. Equipment Certification Under A Proof Of Performance Standard......................................... 257 
I. Other Matters ............................................................................................................................... 262 
1. Certification By Telecommunications Certification Bodies.................................................. 262 
2. Operation In Border Areas .................................................................................................... 263 
3. Reconsideration Of Marketing Date For Unlicensed TV Band Devices............................... 267 
4. Emergency Request For Additional Comment Period .......................................................... 269 
V. PROCEDURAL MATTERS.............................................................................................................. 270 
VI. ORDERING CLAUSES..................................................................................................................... 272 
APPENDIX A - Parties Filing Comments

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APPENDIX B - Final Rules 
APPENDIX C - Final Regulatory Flexibility Analysis 
I. EXECUTIVE SUMMARY 
1. In this Second Report and Order, we adopt rules to allow unlicensed radio transmitters to 
operate in the broadcast television spectrum at locations where that spectrum is not being used by licensed 
services (this unused TV spectrum is often termed white spaces). This action will make a significant 
amount of spectrum available for new and innovative products and services, including broadband data 
and other services for businesses and consumers. The actions we take here are a conservative first step 
that includes many safeguards to prevent harmful interference to incumbent communications services. 
Moreover, the Commission will closely oversee the development and introduction of these devices to the 
market and will take whatever actions may be necessary to avoid, and if necessary correct, any 
interference that may occur. Further, we will consider in the future any changes to the rules that may be 
appropriate to provide greater flexibility for development of this technology and better protect against 
harmful interference to incumbent communications services. Briefly, the rules we are adopting provide 
for the following capabilities and safeguards: 
 We are providing for both fixed and personal/portable devices to operate in the TV white 
spaces on an unlicensed basis. 
 All devices, except personal/portable devices operating in client mode, must include a 
geolocation capability and provisions to access over the Internet a database of protected radio 
services and the locations and channels that may be used by the unlicensed devices at each 
location. The unlicensed devices must first access the database to obtain a list of the 
permitted channels before operating. 
 The database will be established and administered by a third party, or parties, to be selected 
through a public notice process to solicit interested parties. 
 Fixed devices may operate on any channel between 2 and 51, except channels 3, 4 and 37, 
and subject to a number of other conditions such as a restriction against co-channel operation 
or operation adjacent TV channels pending consideration of further information that may be 
submitted into the record in this proceeding. Fixed devices may operate at up to 4 Watts 
EIRP (effective isotropic radiated power). 
 Personal portable devices may operate on any unoccupied channel between 21 and 51, except 
channel 37. Personal portable devices may operate at up to 100 milliwatts of power, except 
that operation on adjacent channels will be limited to 40 milliwatts. 
 Fixed and personal/portable devices must also have a capability to sense TV broadcasting and 
wireless microphone signals as a further means to minimize potential interference. However, 
for TV broadcasting the database will be the controlling mechanism. 
 Wireless microphones will be protected in a variety of ways. The locations where wireless 
microphones are used, such as entertainment venues and for sporting events, can be registered 
in the database and will be protected as for other services. In addition, channels from 2  20 
will be restricted to fixed devices, and we anticipate that many of these channels will remain 
available for wireless microphones that operate on an itinerant basis. In addition, in 13 major 
markets where certain channels between 14 and 20 are used for land mobile operations, we 
will leave 2 channels between 21 and 51 free of new unlicensed devices and therefore 
available for wireless microphones. Finally, as noted above, we have required that devices 

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also include the ability to listen to the airwaves to sense wireless microphones as an 
additional measure of protection for these devices. 
 Devices must adhere to certain rules to further mitigate the potential interference and to help 
remedy potential interference should it occur. For example, all fixed devices must register 
their locations in the database. In addition, fixed devices must transmit identifying 
information to make it easier to identify them if they are found to interfere. Furthermore, 
fixed and personal/portable devices operating independently must provide identifying 
information to the TV bands database. All devices must include adaptable power control so 
that they use the minimum power necessary to accomplish communications. 
 All white space devices are subject to equipment certification by the FCC Laboratory. The 
Laboratory will request samples of the devices for testing to ensure that they meet all the 
pertinent requirements. 
 We will permit applications for certification of devices that do not include the geolocation 
and database access capabilities, and instead rely on spectrum sensing to avoid causing 
harmful interference, subject to a much more rigorous set of tests by our Laboratory in a 
process that will be open to the public. These tests will include both laboratory and field tests 
to fully ensure that such devices meet a Proof of Performance standard that they will not 
cause harmful interference. Under this procedure the Commission will issue a Public Notice 
seeking comment on the application, as well as test procedures and methodologies. The 
Commission will also issue a Public Notice seeking comment on its recommendations. The 
decision to grant such an application will then be made at the Commission level. 
 The Commission will act promptly to remove any equipment found to be causing harmful 
interference from the market and will require the responsible parties to take appropriate 
actions to remedy any interference that may occur. 
II. INTRODUCTION 
2. In this Second Report and Order, we adopt rules to allow unlicensed radio transmitters to 
operate in the broadcast television spectrum at locations where that spectrum is not being used by licensed 
services (this unused TV spectrum is often termed white spaces). This action will open for use a 
significant amount of spectrum with very desirable propagation characteristics that has heretofore lain 
fallow. These new rules will allow the development of new and innovative types of unlicensed devices 
that provide broadband data and other services for businesses and consumers without disrupting the 
incumbent television and other authorized services that operate in the TV bands. In addition, because 
transmissions on frequencies in the TV bands are less subject to propagation losses than transmissions in 
the spectrum bands where existing low power broadband unlicensed operations are permitted, i.e., the 2.4 
GHz and 5 GHz bands, we anticipate that allowing unlicensed operation in the TV bands will benefit 
wireless internet service providers (WISPs) by extending the service range of their operations. This will 
allow wireless broadband providers that use unlicensed devices to reach new customers and to extend and 
improve their services in rural areas. We anticipate that allowing use of the TV white spaces by 
unlicensed devices will have significant benefits for both businesses and consumers and thereby promote 
more efficient and effective use of the TV spectrum. 
3. The plan we are adopting will allow both fixed and personal/portable unlicensed devices 
to operate on unused television channels in locations where such operations will not result in harmful 
interference to TV services (including reception by cable headends and low power TV stations, i.e., TV 
translator, low power TV, TV booster, and Class A TV stations) and other services that use the TV 

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bands.1 We recognize the importance of protecting licensed services from harmful interference and the 
novel challenges involved in reliably identifying unused TV channels. We therefore are taking a cautious 
and conservative approach in this plan, balancing the need to provide sufficient opportunities for 
proponents to develop viable unlicensed TV band devices (TVBDs) with measures to ensure that such 
devices fully protect the important licensed services that operate in the TV bands. In allowing the 
introduction of unlicensed TVBDs, we also believe it is important to avoid the possibility of disrupting or 
causing uncertainty in the DTV transition, the current ongoing process whereby TV stations are changing 
from analog to digital (DTV) operation. As set forth in the First Report and Order and Further Notice of 
Proposed Rulemaking (First R&O/Further Notice) in this proceeding, we have addressed this concern 
with regard to the DTV transition by restricting the marketing of unlicensed TVBDs until February 18, 
2009, the date when the DTV transition will end and all full-power TV stations will be operating on a 
single channel, and only with digital signals.2 
4. We anticipate that the capabilities of products for operating in this spectrum will develop 
and evolve over time and that much will be learned about the potential for unlicensed TVBDs to cause 
interference to licensed services and how to avoid that interference. We may therefore need to revisit 
these rules to make adjustments both to provide more flexibility for unlicensed devices and to refine the 
protections for licensed services. Consistent with our objective to allow unlicensed TVBDs to operate 
with the most flexibility and capabilities possible consistent with protection of licensed services, we are 
directing our staff to conduct a review and report to the Commission in two years from the date of this 
Second Report and Order on the state of these devices, including the types of devices on the market, the 
extent of their implementation, technical developments, any interference problems that may have arisen, 
and aspects of the rules that should be altered to increase features and opportunities for use or to address 
conflicts. 
5. We are also denying all aspects of a petition for reconsideration submitted by the New 
America Foundation and the Champaign Urbana Wireless Network (NAF/CUWN).3 In particular, we are 
denying their request that we 1) not re-open the issue of whether to permit new uses of the TV bands on a 
licensed or unlicensed basis; 2) allow personal/portable devices on channels 14-20; and 3) allow 
marketing of new unlicensed TV band devices prior to the end of the DTV transition. 
6. Overview of Rules for Unlicensed TV Band Devices. The new rules provide for operation 
of two types of unlicensed TVBDs that may provide broadband data and other types of communications 
services: 1) fixed devices, which will operate from a fixed location with relatively higher power and 
could be used to provide a variety of services including wireless broadband access in urban and rural 
areas, and 2) personal/portable devices, which will use lower power and could, for example, take the form 
1 As discussed below, the TV spectrum is also used on a licensed basis by wireless microphone, private land mobile 
radio, commercial mobile radio, broadcast auxiliary, off-shore radio, and radio astronomy operations. TV 
translators are low power TV stations that receive a signal from a full service TV station on one channel and 
retransmit that signal on a different channel in an area where the full service TV station is not normally received. 
Low power TV stations operate similar to TV translators and may retransmit the signals of a full service TV station 
and also originate programming. TV booster stations also operate similar to TV translators but transmit on the same 
channel as their full service station and within the service area of that full service station. Class A stations operate 
under technical rules similar to low power TV and TV translator stations but are subject to certain minimum 
operating requirements for service hours and locally originated programming. 
2 See First Report and Order and Further Notice of Proposed Rule Making in ET Docket Nos. 02-380 and 04-186, 
21 FCC Rcd 12266 (2006). 
3 See Petition for Reconsideration of the First R&O/Further Notice submitted by the NAF and the Champaign 
Urbana Wireless Network, December 18, 2006. 

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of devices such as Wi-Fi-like cards in laptop computers or wireless in-home local area networks (LANs). 
In order to operate without causing interference to licensed services, both types of devices will be 
required to be able to reliably determine which channels are occupied by licensed operations at their 
location at any given time and to avoid interfering with services on those channels using the following 
methods. Devices will be required to identify unused channels as follows: 
a) A fixed device must employ both geo-location/database access and spectrum sensing 
capabilities that enable the device to listen for and identify the presence of signals from other 
transmitters; 
b) A personal/portable device must either 1) be under the control of a fixed device or a 
personal/portable device that employs geolocation/database access and spectrum sensing or 
2) employ geo-location/database access and spectrum sensing itself. 
7. In addition, we are adopting rules that will allow for certification of personal/portable 
devices that do not include geo-location and database access capabilities and are not controlled by another 
device but rather determine available channels using spectrum sensing, perhaps in combination with some 
other techniques. These devices will be required to meet a proof of performance standard that they will 
not cause harmful interference to incumbent radio services. Such devices will be subject to all of the 
other requirements for personal/portable devices but would be limited to 50 milliwatts (mW) EIRP rather 
than the 100 mW authorized for personal/portable devices for which available channels are determined 
based on the geolocation and database method. The certification process will require submittal of a 
sample for testing in our laboratory and in the field similar to the process that the FCC Laboratory 
followed for testing of TV band devices. The sample device must be a fully functioning pre-production 
prototype, identical to the device that will be marketed except for cosmetics. The testing will be open to 
the public. The application must also show how the device will protect the various incumbent radio 
services discussed herein. The determination of whether to certify the device will be based on a 
demonstrated ability to avoid causing harmful interference with an extremely high degree of reliability. If 
the device is certificated, we will permit routine certification of other devices that have identical 
characteristics (i.e., have the identical electrical characteristics and antenna system.). We will endeavor to 
complete the certification process within 180 days of submittal of the device for testing, barring any 
unforeseen circumstances. 
8. Fixed Devices. Fixed devices will be allowed to communicate with other fixed devices 
and with personal portable devices. These devices will be required to determine their geographic location 
through an incorporated geo-location capability or from a professional installer and to access and register 
with a database system that contains records of protected services and receive back either a list of the 
available channels at their location or information on the channels used in their area from which they can 
determine a list of available channels. In addition, fixed devices will be required to operate with antennas 
mounted outdoors and to use spectrum sensing to identify any wireless microphone operations and any 
other protected signals that might be present at their location but do not appear in the database. These 
devices will be required to sense, at levels as low as -114 dBm, TV signals (digital and analog), wireless 
microphone signals, and signals of other services that operate in the TV bands on intermittent basis. 
Fixed devices will be allowed to operate at up to 1 watt (W) transmitter output power and with a gain 
antenna to achieve 4 W equivalent isotropically radiated power (EIRP), and to communicate with other 
fixed devices and personal/portable devices, except that they may not communicate with 
personal/portable devices when operating on channels in the range 2-20. This plan for fixed devices is 
similar to the provisions of the draft standard for TVBDs under consideration by IEEE 802.22.4 
4 See IEEE 802.22/D0.2 Draft Standard for Wireless Regional Area Networks Part 22: Cognitive Wireless RAN 
Medium Access Control (MAC) and Physical Layer (PHY) specifications: Policies and procedures for operation in 
(continued.)

Federal Communications Commission FCC 08-260 
6 
9. Personal/portable Devices. Personal/portable devices will be allowed to communicate 
with fixed devices and with other personal/portable devices. These devices will be allowed to operate in 
two different modes: 1) Mode I - client, whereby a personal/portable device is controlled by a fixed or a 
personal/portable device operating in Mode II that has determined the available channels in the area 
and/or 2) Mode II - independent, whereby a personal/portable device determines the available channels 
using its own internal geo-location/database access capabilities. Personal/portable operations will be 
permitted at up to 100 mW EIRP, with no antenna gain, except that when operating on a channel adjacent 
to a TV station or other licensed station/service and within the protected coverage area of that service, 
operations will be limited to 40 milliwatts. A device operating in Mode II using its own internal geolocation 
and database access capabilities will be allowed to communicate with other personal/portable 
devices and function as the master device in a master/client link with another personal/portable device. 
Devices operating in either mode will be required to sense TV signals, wireless microphone signals, and 
signals of other services that operate in the TV bands, including those that operate on intermittent basis, at 
levels as low as -114 dBm. Personal portable devices will not be required to register with the database 
system. 
10. All Devices. All unlicensed TV band fixed and personal/portable TV band devices will 
be permitted to operate on TV channels 21-51, excluding channel 37. In addition, fixed TVBDs that only 
communicate with other fixed TVBDs will be permitted to operate on channels 2 and 5-20, except that 
they must avoid operation on channels used by private land mobile radio service (PLMRS), i.e., public 
safety, and commercial mobile radio service operations on channels in certain markets and areas adjacent 
to them. Also, in individual markets where there are Private Land Mobile Radio Service or Commercial 
Mobile Radio Service (PLMRS/CMRS) operations on channels 14-20, two channels in the range 21-51 
will be reserved for operation by wireless microphones such that TVBDs will not be permitted on those 
channels. This plan for channel use is consistent with the requests of the various white space proponents 
and would reserve channels for a safe harbor for operation of wireless microphones and ensure 
protection of the public safety and other land mobile services that use channels 14-20. At this time, we 
are only permitting fixed TVBDs to operate on channels not that are not immediately next to (first 
adjacent on either side of) the channel of a TV station; personal portable devices will be allowed to 
operate on first adjacent channels to a TV station subject to the power limitation indicated above. All 
unlicensed TV band devices will be required to limit their out-of-band emissions in the first adjacent 
channel to a level 55 dB below the power level in the channel they occupy, as measured in a 100 kHz 
bandwidth. In addition, all TVBDs will be required to comply with a more stringent out-of-band 
emissions band at the edges of channels 36 and 38 that are adjacent to channel 37 in order to protect 
medical telemetry devices on that channel 37. Fixed devices will also be required to periodically transmit 
a signal with their identification when they are operating. This will facilitate identification of sources of 
interference. The database system for fixed stations and personal/portable devices with geo-location and 
database access capability will be managed by a database manager or managers selected by our Office of 
Engineering and Technology. The specific provisions of this plan are presented below. 
III. BACKGROUND 
11. The Commission provides for the operation of unlicensed radio transmitters in Part 15 of 
its rules.5 Under these rules, unlicensed devices generally operate on frequencies shared with authorized 
(Continued from previous page) 
the TV Bands, prepared by the IEEE 802.22 Working Group of the LAN/MAN Standards Committee, November 
2006. We note, however, that the IEEE 802.22 plan does not provide for fixed devices to communicate with 
personal/portable devices on a master/client basis. 
5 See 47 C.F.R. Part 15.

Federal Communications Commission FCC 08-260 
7 
services and at relatively low power, i.e., at power levels 1 W or less. Operation under Part 15 is subject 
to the condition that a device does not cause harmful interference to authorized services, and that it must 
accept any interference received.6 The current Part 15 rules provide substantial flexibility in the types of 
unlicensed devices that can be operated, but prohibit the operation of unlicensed devices on certain 
frequencies, including the bands used for broadcast television service.7 
12. The broadcast television service operates under Part 73 of the rules. TV stations operate 
on six-megahertz channels designated channels 2 to 69 in four bands of frequencies in the VHF and UHF 
regions of the radio spectrum (54-72 MHz, 76-88 MHz, 174-216 MHz and 470-806 MHz).8 As noted 
above, television stations are now in the process of converting from analog to digital transmissions.9 
During the transition to digital transmissions, each full service television station that was authorized before 
1997 is required to broadcast on two channels, one digital and one analog.10 At the end of the transition on 
February 17, 2009, each full service TV station must cease analog operation and operate on a single digital 
channel.11 Because the new digital TV transmission system is more spectrally efficient than the analog TV 
transmission system, the Commission has relaxed some of the current analog TV channel separation 
requirements for digital operation and has eliminated others. Consequently, it has been able to accommodate 
all existing television stations with channels for post-transition operation in less spectrum. The Commission 
has specified that digital television stations will operate only on channels 2-51 after the transition and has 
reallocated television channels 52-69 for other uses.12 
13. To avoid interference between TV stations, stations on the same and adjacent channels 
(and in the case of analog TV service certain other channel relationships) must comply with minimum 
6 See 47 C.F.R.  15.5. 
7 See 47 C.F.R.  15.205 and 15.209. Section 15.205 sets forth the restricted bands for operation where unlicensed 
intentional radiators are not allowed to operate. Section 15.209 provides the general radiated emission limits that 
apply to intentional radiators, including limits on their out-of-band emissions. Remote control and medical 
telemetry devices are the only unlicensed transmitters that are currently permitted to operate in the TV bands. See 
47 C.F.R.  15.231, 15.241 and 15.242. 
8 See 47 C.F.R.  73.603(a). After February 17, 2009, only low power television stations will be permitted to 
operate on channels 52-69. 
9 See for example, Advanced Television Systems and Their Impact upon the Existing Television Broadcast Service, 
MM Docket 87-268, Sixth Report and Order, 12 FCC Rcd 14588 (1997). 
10 The analog and digital TV channels currently used by full service TV stations are set forth in Sections 73.606 and 
73.622 of the rules, respectively, see 47 C.F.R.  73.606 and 73.622. In developing the initial Table of Allotments 
for stations digital TV operations, the channels were selected to minimize or prevent interference between digital 
stations and between analog and digital stations. Requests for modification of stations on channels in the initial 
(1998) DTV Table of Allotments are evaluated for technical acceptability using minimum desired-to-undesired 
(D/U) signal ratios, see 47 C.F.R.  73.623(c). New digital allotments added after the initial digital TV Table of 
Allotments must meet minimum separation distances to both digital and analog TV stations, see 47 C.F.R. 
 73.623(d). The Commission has issued a Report and Order in the third DTV periodic review in which it, inter 
alia, modified the technical standards for new stations and modifications of digital and analog stations to prepare for 
stations final conversion to all digital operation, see Report and Order in MB Docket No. 07-91,23 FCC Rcd 2994 
(2007). 
11 See Title III of the Deficit Reduction Act of 2005, Pub. L. 109171, 120 Stat. 4, 21 (Feb. 8, 2006). 
12 See Sixth Report and Order in MM Docket No. 87-268, supra; see also, First Report and Order in WT Docket No. 
99-168, 15 FCC Rcd 476 (2000), Report and Order in ET Docket No. 97-157, 12 FCC Rcd 22953 (1998) and 
Report and Order in GN Docket No. 01-74, 17 FCC Rcd 1022 (2002).

Federal Communications Commission FCC 08-260 
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separation distance requirements and other technical provisions.13 As a result of these provisions, there 
are geographic areas between the stations on any given channel in local areas where TV service is not 
available. There are typically a number of TV channels in a given geographic area that are not being used 
by full service digital TV stations because such stations would not be able to operate without causing 
interference to co-channel or adjacent channel stations. The minimum separation distances (spacings) 
between stations are based on the assumption that the stations will operate at the maximum permitted 
antenna height and power.14 However, a transmitter operating on a vacant TV channel, e.g., a channel not 
used by a high power TV station in a given geographic area due to interference concerns, at a lower 
antenna height and/or power level than a TV station operating at the maximum allowed facilities would 
not need as great a separation distance from co-channel and adjacent channel TV stations to avoid causing 
interference to such stations. Also, in some areas channels that could be used by a full service television 
station simply are not being used. This situation will remain after the transition. 
14. In addition to full service TV stations operating under Part 73 of the rules, certain other 
licensed services are permitted to operate on TV channels. Class A television stations operate under 
Subpart J of Part 73 of the rules.15 Low power TV, TV translator and TV booster stations are permitted to 
operate under Part 74 of the rules on a secondary basis to full service TV stations and on an equal basis 
with Class A TV stations, provided they meet technical rules to prevent interference to reception of such 
stations.16 Part 74 also permits certain broadcast auxiliary operations on TV channels 14-69 on a 
secondary basis.17 In addition, Part 74 permits certain entities to operate wireless microphones on vacant 
TV channels on a non-interference basis.18 
15. Further, in 13 metropolitan areas, one to three channels in the range of channels 14-20 are 
used by licensees in the Private Land Mobile Radio Service under Part 90 of the rules and the 
Commercial Mobile Radio Service under Part 20 of the rules.19 In addition, medical telemetry equipment 
is permitted to operate on an unlicensed basis on any vacant TV channels in the range of channels 7-46, 
and unlicensed remote control devices are allowed to operate on any TV channels above 70 MHz (i.e., 
above channel 4), except for channel 37.20 TV channel 37 (608-614 MHz) is allocated for radio 
13 See 47 C.F.R.  73.610, 622, 623, and 699. 
14 The separations differ depending on the zone where the stations are located and whether the stations are in the 
VHF or UHF band. See 47 C.F.R.  73.623(d). 
15 See 47 C.F.R. Part 73 Subpart J. Class A TV stations operate at the power levels permitted for low power 
television stations under Part 74 of the rules, but have certain protection rights with respect to full service analog and 
digital TV stations that are not available to TV translator and low power stations. 
16 See 47 C.F.R. Part 74 Subpart G. 
17 See 47 C.F.R.  74.602(h). This rule section permits TV studio-transmitter links, TV relay stations, and TV 
translator relay stations to be authorized to operate fixed point-to-point service on UHF TV channels 14-69 on a 
secondary basis, subject to the provisions in Part 74, subpart G. 
18 See 47 C.F.R.  74.861. 
19 See 47 C.F.R. Part 90 Subpart L and 47 C.F.R. Part 22 Subpart E. 
20 See 47 C.F.R.  15.231, 15.241 and 15.242. Effective October 16, 2002, the Commission ceased granting 
certifications for new medical telemetry equipment that operates on TV channels, but there is no cutoff on the sale 
or use of equipment that was certified before that date, see 47 C.F.R.  15.37(i). To provide spectrum for wireless 
medical telemetry equipment, the Commission established the Wireless Medical Telemetry Service to operate on a 
primary basis in 13.5 megahertz of spectrum in three spectrum blocks at 608-614 MHz (TV channel 37, which the 
WMTS now shares with radio astronomy), 1395-1400 MHz, and 1427-1429.5 MHz. See Amendment of Parts 2 and 
95 of the Commission's Rules to Create A Wireless Medical Telemetry Service, Report and Order, ET Docket No. 
(continued.)

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astronomy and the wireless medical telemetry service (WMTS) and is not used for TV broadcasting. The 
Offshore Radiotelephone Service uses channels 15-17 in certain regions along the Gulf of Mexico.21 In 
Hawaii, channel 17 is reserved for inter-island communications.22 However, no active licensees currently 
use this channel in Hawaii, so we will not provide for protection of inter-island communications 
operations on channel 17 there unless or until an inter-island communications system is activated in that 
state. 
16. On May 13, 2004, the Commission adopted a Notice of Proposed Rule Making (Notice) 
in this proceeding in which it proposed to allow unlicensed operation in the TV bands at locations where 
frequencies are not in use by licensed services.23 To ensure that no harmful interference will occur to TV 
stations and other authorized users of the spectrum, the Commission proposed to define the conditions 
under which a TV channel is unused and to require unlicensed devices to incorporate smart radio 
features to identify the unused TV channels in the area where they are located. For the purpose of 
minimizing interference, the Commission proposed to classify unlicensed TVBDs in two general 
functional categories. The first category would consist of lower power personal/portable unlicensed 
devices, such as Wi-Fi-like cards in laptop computers or wireless in-home local area networks (LANs). 
The second category would consist of higher power fixed unlicensed devices that would operate from a 
fixed location and could be used to provide commercial services such as wireless broadband Internet 
access. The Commission proposed to require that fixed devices incorporate a geo-location method such 
as a Global Positioning System (GPS) receiver or be professionally installed, and that they access a 
database system to identify vacant channels at their location. It further proposed to require that 
personal/portable devices operate only when they receive a control signal from a source such as a TV 
station or FM radio station that identifies the vacant TV channels in that particular area. The Commission 
also sought comment on the use of spectrum sensing to identify vacant TV channels, but did not propose 
any specific technical criteria for spectrum sensing. 
17. The comments received in response to the Notice were divided between the prospective 
manufacturers and users of unlicensed devices who believe adequate safeguards can be put in place to 
prevent harmful interference to authorized services, and the existing users of the TV bands who are 
concerned about potential interference. A number of broadband equipment manufacturers, trade 
associations and other parties supported allowing unlicensed operation in the TV bands. These parties 
generally stated that unlicensed devices could operate in the TV bands without causing interference to 
authorized services. They further stated that allowing such operation in the TV bands could improve 
access to broadband communications by taking advantage of the favorable propagation characteristics of 
the TV spectrum and that this would result in more efficient use of this spectrum.24 
(Continued from previous page) 
99-255, 15 FCC Rcd 11206 (2000). See also, Amendments to Parts 1, 2, 27, and 90 of the Commission's Rules to 
License Services in the 216-220 MHz, 1390-1395 MHz, 1427-1429 MHz, 1429-1432 MHz, 1432-1435 MHz, 1670- 
1675 MHz, and 2385-2390 MHz Government Transfer Bands, WT Docket No. 02-8, Memorandum Opinion and 
Order, 18 FCC Rcd 16920 (2003). 
21 See 47 C.F.R.  2.106 NG66(b) and 47 C.F.R.  22.1007. 
22 See 47 C.F.R.  22.591. 
23 See Notice of Proposed Rule Making in ET Docket Nos. 02-380 and 04-186, 19 FCC Rcd 10018 (2004). 
24 See Intel Notice comments at 2, Microsoft Notice comments at 3, Consumer Electronics Association (CEA) 
Notice reply comments at 3, Motorola Notice comments at 1, Telecommunications Industry Association (TIA) 
Notice comments at 4, IEEE 802 Notice comments at 4, NAF Notice comments at 1, and Wireless Internet Service 
Providers Association (WISPA) Notice comments at 4.

Federal Communications Commission FCC 08-260 
10 
18. Full service and low power TV broadcasters generally opposed allowing unlicensed 
operation in the TV bands, expressing concern that unlicensed devices operating under the proposed rules 
would cause interference to TV reception, particularly in weak signal areas.25 Several parties also 
expressed concern that unlicensed devices operating in close proximity to TV receivers would cause 
direct pick-up interference potentially affecting all channels.26 Manufacturers and users of wireless 
microphones and other broadcast auxiliary services submitted that unlicensed devices would cause 
harmful interference to those services. Those parties recommended that the Commission take a number 
of steps to protect auxiliary services.27 Land mobile interests expressed concern about allowing 
unlicensed operation on channels 14-20 in any part of the country because devices could be transported 
into areas where those channels are used for PLMRS/CMRS operations.28 
19. On October 12, 2006, the Commission adopted the First R&O/Further Notice in this 
proceeding. In that action, the Commission determined that the record received in response to the Notice 
did not contain sufficient information for it to adopt final rules for unlicensed TVBDs. The Commission 
did, however, make a number of initial decisions regarding TVBDs. It decided to permit fixed unlicensed 
power devices to operate in the TV bands at times and locations where the spectrum is not already being 
used by other authorized services. It also decided not to permit operation of unlicensed TVBDs on 
channel 37, which is used by radio astronomy and wireless medical telemetry services, and on TV 
channels 52-69, as that spectrum has been reallocated for other services and will no longer be part of the 
TV bands after the DTV transition. The Commission further decided to prohibit operation of 
personal/portable TV band devices on TV channels 14-20 to avoid potential conflicts with public safety 
services on those channels. In addition, the Commission stated that it will not permit marketing of TV 
band devices to commence until February 18, 2009, the date on which all primary, full service TV 
stations will be in operation on their permanent DTV channels. 
20. In the First R&O/Further Notice, the Commission also asked questions and set forth 
additional proposals with regard to the provisions necessary to implement complete and final rules for 
unlicensed TV band devices. While the Commission continued to focus on devices operating on an 
unlicensed basis, it also sought comment on whether such devices should instead operate on a licensed or 
hybrid basis. The Commission recognized the importance of conducting testing to ensure that whatever 
standards are ultimately adopted will protect incumbent radio services from interference and indicated 
25 See, for example, National Cable and Telecommunications Association (NCTA) Notice reply comments at 4, 
National Association of Broadcasters and Association for Maximum Service Television (NAB/MSTV) Notice reply 
comments at 6, Society of Broadcast Engineers (SBE) Notice reply comments at 1, Community Broadcasters 
Association (CBA) Notice reply comments at 3, National Translator Association (NTA) Notice comments at 1, 
Entravision Holdings Notice comments at 2, Southwest Colorado TV Translator Association Notice comments at 1, 
Syncom Media Group Notice comments at 1, Cox Broadcasting (Cox) Notice comments at 8, Pappas Telecasting 
(Pappas) Notice comments at 8, and Region 1 Translator Association Notice comments at 2. 
26 Direct pick-up interference occurs when undesired signals are received on the internal circuitry of a receiver, 
rather than at its input terminal as received from an attached antenna. See NAB/MSTV reply comments at 14, CEA 
comments at 10, and NCTA comments at 5. 
27 See, for example, Shure Notice comments at 9, Telex Communications Notice comments at 2, ATK Audiotek 
Notice comments at 2, Michael Mason Notice comments at 2, Total RF Marketing Notice comments at 6, Society of 
Broadcast Engineers Notice comments at 2, Sennheiser Electronic Corporation Notice comments at 2, National 
Systems Contractors Association Notice comments at 3, and Professional Audio Manufacturers Alliance Notice 
comments at 3. 
28 See Motorola reply comments at 4, Land Mobile Communication Council (LMCC) Notice reply comments at 3, 
Industrial Telecommunications Association (ITA) Notice comments at 1, County of Los Angeles Notice comments 
at 2, and Association of Public Safety Communications Officials (APCO) Notice comments at 3.

Federal Communications Commission FCC 08-260 
11 
that it intended to conduct extensive testing to assess the potential interference from low power devices 
operating in the TV bands. It also requested further comment and information on the means that TVBDs, 
both fixed and personal/portable, should be required to use to determine the availability of unused 
spectrum. It specifically requested comment on whether it should allow personal/portable devices to rely 
on spectrum sensing and, if so, the technical features and parameters of the sensing capability to be 
required. The Commission observed that IEEE 802.22 is considering different sensing threshold 
detection levels depending on the nature of the source signal, with levels as low as -116 dBm, and invited 
comment on this value or alternative values for the detection threshold. It also made specific proposals 
for additional parameters of spectrum sensing capabilities and other technical requirements. The 
Commission sought comment on whether TV band devices should be permitted to operate on TV 
channels 2-4, and whether fixed TV band devices should be permitted to operate on TV channels 14-20. 
The Commission also sought additional comments on several issues relating to the geo-location/database 
access and control signal approaches discussed in the Notice. 
21. The comments responding to the First R&O/Further Notice are again divided on certain 
of the major issues in this proceeding. Two groups, one a coalition of hardware and software companies 
consisting of Dell, Google, HP, Intel, Microsoft and Phillips (the White Space Coalition) and the other a 
group of public interest/consumer organizations and wireless internet service providers (WISPs), led by 
the NAF, strongly support low power, unlicensed use of the TV bands. In addition, some other 
manufacturers and a number of WISPs express support for that approach separately from these groups. 
Proponents of unlicensed devices believe that the Commission should allow both fixed and 
personal/portable devices. They also support allowing personal/portable devices to rely solely on 
spectrum sensing to determine the available channels at their location. The White Space Coalition 
supports limiting unlicensed operation to channels 21-51 (excluding 37), while the group led by the NAF 
believes that operation should be permitted on as many channels as possible, including channels 2-4 and 
channels 14-20 in locations where public safety and land mobile services are not using them. 
22. Full service and low power TV broadcasters and cable TV interests generally state that 
any new services in the TV bands should be licensed to reduce the likelihood of interference to incumbent 
services. They oppose the introduction of personal/portable devices at this time and believe that any new 
services should be limited to fixed operation. Broadcasters contend that spectrum sensing alone is 
inadequate to protect against interference to broadcast operations and that sensing must be combined with 
geo-location/database access to ensure that low power devices do not operate inside the protected service 
contours of co-channel or adjacent-channel TV stations.29 Low power TV and translator operators 
express concern that low power unlicensed devices would cause interference to viewers who rely on 
reception outside their stations protected service contours, while cable interests express concern about 
possible interference to reception of TV signals by cable headends that are located outside TV stations 
protected contours. Both broadcast and cable interests express concern about direct pick-up interference 
to TV receivers, particularly from personal/portable devices. 
23. Wireless microphone manufacturers and users again recommend that the Commission 
adopt a number of requirements to prevent interference to wireless microphones, including: 1) limiting 
new low power devices to fixed operation, 2) prohibiting new low power devices from operating on 
29 The protected service contour for DTV and analog TV stations are contours that define the edge of a stations 
service area where the availability of service is limited by noise. The DTV and analog protected service contours 
are generally termed the noise-limited and Grade B contours, respectively; the definitions of these contours are 
set forth in Sections 73.622(e) and 73.683 of the rules, respectively. See 47 C.F.R.  73.622(e) and 683. The 
definitions of the protected service contours of low power DTV and analog stations are specified at signal strength 
levels that are higher than the noise-limited levels. See Sections 73.6010, 74.707 and 74.792 of the rules; see also 
47 C.F.R.  73.6010 and 74.707 and 792.

Federal Communications Commission FCC 08-260 
12 
channels adjacent to occupied TV channels and/or reserving six vacant TV channels in each market for 
wireless microphones to ensure that spectrum is available for their use, 3) requiring new low power 
devices to incorporate spectrum sensing to detect wireless microphones, and 4) requiring new low power 
devices to sense for the presence of a smart beacon that would be operated when wireless microphones 
are in use in an area (Shure has since repudiated its support for a beacon requirement).30 Public 
safety/land mobile interests believe that new low power devices should not be allowed to operate on 
channels 14-20 anywhere in the country because of the difficulties in enforcing geographic restrictions on 
operation. 
24. On March 30, 2007, the Commissions Office of Engineering and Technology released a 
report on the results of its DTV receiver testing program.31 This testing program examined the out-ofchannel 
interference rejection performance of a representative sample of eight DTV receivers with fifth 
generation tuners that were available in 2005 and 2006. A total of 2055 individual measurements were 
performed on these receivers. Each test involved feeding a desired signal to the television under test and 
injecting an interfering signal on a different channel or combination of channels. The different tests varied 
the level of the desired signal and interfering signal(s). In these tests, no receiver appeared to fully 
achieve the Advanced Television Systems Committees (ATSC) recommended guidelines for interference 
rejection performanceguidelines that are generally more stringent than the receiver performance 
assumptions on which current DTV interference protection criteria are based.32 
25. On July 31, 2007, the Office of Engineering and Technology released a technical report 
on an initial study of prototype TV band devices that were submitted to the Commissions Laboratory for 
testing.33 This report evaluated the performance of two samples of prototype devices; one device had 
both sensing and transmitting capabilities (although the two functions were not linked) and the other had 
only sensing capability. This testing found that one of the two devices was generally able to reliably 
detect TV signals in the laboratory bench tests at the claimed -114 dBm sensing level, but did not perform 
well sensing wireless microphones. This device was not tested in the field at the manufacturers request. 
The other device was not able to reliably sense either TV or wireless microphone signals at the -114 dBm 
level in either the Laboratory bench tests or in field tests. The builder of this device subsequently 
determined that the devices sensing function was not operating properly. In an anecdotal observation, 
the transmitter of the second device was found to cause co-channel and adjacent channel interference to 
TV service at distances of 87 meters and 47-50 meters, respectively. 
30 See Shure ex parte comments in ET Docket No. 04-186 submitted May 6, 2008. 
31 See Office of Engineering and Technology, Interference Rejection Thresholds of Consumer Digital Television 
Receivers Available in 2005 and 2006, OET Report FCC/OET 07-TR-1003, March 30, 2007 (DTV Receiver 
Study). Peer review of this report was undertaken in accordance with OMB Final Information Quality Bulletin for 
Peer Review, 70 Fed. Reg. 2664 (Jan. 14, 2005). 
32 The ATSC provides recommended guidelines for DTV receiver performance in its document, ATSC 
Recommended Practice: Receiver Performance Guidelines, ATSC Doc. A/74, 17 June 2004. The DTV Receiver 
Study found that, after taking into account differences between the Gaussian-noise interferer used for most of the 
tests and the 8-VSB interferer specified by the ATSC, the best-performing receiver failed to meet the guidelines at 
only one channel offset, and by only 1 dB. A second receiver failed to meet the voluntary guidelines by 1 to 2 dB at 
two channel offsets. The remaining five receivers failed to meet the guidelines at two to 16 channel offsets; the 
worst failure for each of those receivers ranged from about 8 to 24 dB. 
33 See Office of Engineering and Technology Initial Evaluation of the Performance of Prototype TV-Band White 
Space Devices, OET Report FCC/OET 07-TR-1006, July 31, 2007 (Initial Measurements Report). Devices were 
submitted for this initial testing by Microsoft Corporation and Philips Electronics North America Corporation. Peer 
review of this report was undertaken in accordance with OMB Final Information Quality Bulletin for Peer Review, 
70 Fed. Reg. 2664 (Jan. 14, 2005). 

Federal Communications Commission FCC 08-260 
13 
26. Also on July 31, 2007, the Office of Engineering and Technology released a second 
technical report describing direct pick-up interference tests of three digital cable ready television 
receivers.34 In these tests, three digital cable ready (DCR) receivers connected directly to cable service 
were examined for their susceptibility to interference from devices such as might operate within the TV 
white spaces. Tests were performed with the interfering signal source separated from the DCR receiver 
by distances of 2 meters or ten meters and, in most observations, by a residential wall. These tests 
showed that a signal as low as 6.3 dBm EIRP could cause interference at a distance of two meters and that 
a signal as low as 15.3 dBm could cause interference at a distance of 10 meters.35 While these tests were 
limited in scope (only three receivers were tested), they nonetheless provide an empirical demonstration 
of the potential for such interference at relatively low power levels. 
27. On October 15, 2008, the Office of Engineering and Technology issued a technical report 
on a second phase of its study of sample prototype TV band devices.36 This second phase study examined 
the performance of prototype devices from five parties. All of these devices had capabilities for sensing 
TV signals, three had capabilities for sensing wireless microphones and one (that of Adaptrum) had a 
transmit capability (this transmit capability was not linked to the devices sensing capabilities). One of the 
devices (that of Motorola) also had a geolocation/database access capability. 
28. In the laboratory tests of TV signals, the Phase II prototype devices were able to detect a 
clean, i.e., unfaded, DTV signal on a single channel at levels in the range of -116 dBm to -126 dBm. 
The detection threshold sensitivity of the devices varied from -106 dBm to -128 dBm when recorded offair 
DTV signals, which included multi-path fading and other real-world distortion, were used. When 
the devices were tested with DTV signals present in adjacent channels, the staff found that in the presence 
of moderate-to-strong signals in a first adjacent channel, the detection threshold sensitivity of all of the 
devices was severely impacted. For some of the devices, the degradation in the detection sensitivity was 
as much as 60-70 dB. In some cases, the degradation was such that the detection threshold could not be 
measured. The Phase II Measurement Report indicates that this could impact significantly the ability of 
the devices to reliably detect TV signals within stations service areas. 
34 See Office of Engineering and Technology Direct-Pickup Interference Tests of Three Consumer Digital Cable 
Television Receivers Available in 2005, OET Report FCC/OET 07-TR-1005, July 31, 2007 (Direct Pickup 
Report). Peer review of this report was undertaken in accordance with OMB Final Information Quality Bulletin for 
Peer Review, 70 Fed. Reg. 2664 (Jan. 14, 2005). 
35 The tests for two meters separation were conducted both with and without an intervening wall between the 
interferer and the TV receiver. The tests with ten meter separation distances were only conducted with an 
intervening wall between the interferer and the TV receiver. 
36 See Office of Engineering and Technology Evaluation of the Performance of Prototype TV-Band White Space 
Devices Phase II, OET Report FCC/OET 08-TR-1005, October 15, 2008 (Phase II Measurement Report). Devices 
were submitted for the Phase II measurement study by Adaptrum, the Institute for Infocomm Research (I2R), 
Microsoft Corporation, Motorola, and Philips Electronics North America Corporation. The report is available at 
http://www.fcc.gov/oet/projects/tvbanddevice/Welcome.html under Published Reports. The release of this report 
was announced by Public Notice. See The FCCs Office of Engineering and Technology Releases Report on Tests 
of Prototype TV White Space Devices, Public Notice, DA 08-2243, ET Docket No. 04-186, rel. Oct. 15, 2008. 
Peer review of this report was undertaken in accordance with OMB Final Information Quality Bulletin for Peer 
Review, 70 Fed. Reg. 2664 (Jan. 14, 2005). The peer review was announced by Public Notice. See The FCCs 
Office of Engineering and Technology Releases Peer Review Panel Report on Tests of Prototype TV White Space 
Devices, Public Notice, DA 09-2390, ET Docket No. 04-186, rel. Oct. 28, 2008.

Federal Communications Commission FCC 08-260 
14 
29. TV sensing field tests were performed at nine locations with four of the prototype 
devices.37 In most cases, the devices correctly reported channels as occupied when the device was 
operated within the service contour of the stations broadcasting on those channels and viewable signals 
were observed on the channels. In some instances, however, three of the devices incorrectly reported 
channels as unoccupied (available) when the device was operated within a stations service contour and 
the signal was viewable. All of the devices reported some channels as occupied when the WSD was 
operated outside of the service contours of stations broadcasting on those channels whether the signal was 
viewable or not. In addition, one device generally reported most channels occupied, whether the device 
was operating inside or outside any service contours and whether the signal was viewable or not. During 
the field tests, the Motorola devices geolocation/database access feature was used in combination with its 
sensing capabilities. In those tests, the Motorola device correctly reported all occupied channels used by 
stations within whose contours the WSD was operated. 
30. The second phase study also examined the ability of devices to sense wireless 
microphones designed to operate under Part 74 of our rules. The two operating devices with wireless 
microphone sensing capability, those of Philips and I2R, were tested in the laboratory for their ability to 
detect wireless microphones (models using both FM/analog and digital) operating within UHF TV 
channels. With no other signals present, the devices were able to detect wireless microphones at levels 
ranging from -103 dBm to -129 dBm depending on the type of microphone, and the device. However, in 
the presence of DTV signals in adjacent channels, the detection threshold of both devices was degraded 
such that it affected the ability of the devices to reliably detect the microphone signals. 
31. Finally, the second phase study conducted tests with the Adaptrum devices transmitter. 
The devices transmitter was characterized in the laboratory and then used to investigate interference 
potential to DTV signal reception. Anecdotal tests demonstrated that co-channel interference would 
occur at line-of-sight distances of up to 360 meters at an EIRP level of approximately +7 dBm when the 
DTV set was receiving a weak signal off-the-air using a receive antenna at a height of 9.3 meters. No 
interference was observed when the device transmitted on an immediate adjacent channel even with the 
transmitter in close proximity to the receiver with a roof-top antenna. No other configurations were tested 
for interference. Anecdotal tests with the Adaptrum transmitter were performed at two field sites to 
assess the interference potential from a TVBD transmitter to cable television reception via direct pick-up 
of signals by cable system components. These tests showed that under certain circumstances, when the 
transmit antenna was placed in close proximity to a cable connected TV, direct pick-up interference 
occurred. The report indicated that the direct pick-up interference potential appears to be highly 
dependent on the interconnection among the various receive system components (e.g., cable amplifiers, 
splitters and set-top boxes) being used 
IV. DISCUSSION 
32. As supported by the record in this proceeding, we conclude that low power devices can 
and should be allowed to operate in the TV bands on frequencies that are not being used by authorized 
services. This decision will provide significant benefits for the public by enabling the development and 
operation of a wide range of new unlicensed wireless communications devices and systems in spectrum 
where signals are less subject to propagation losses than they are in the bands currently available for such 
devices. The propagation characteristics of these bands will allow the development of devices that can 
provide service at greater ranges than existing unlicensed devices. Proponents of broadband devices and 
services in particular indicate that there is need for new broadband devices that will take advantage of the 
more desirable propagation characteristics of the TV bands. As indicated above, we believe that the 
37 The Microsoft sample devices ceased functioning during the test process and were not repaired or replaced. As a 
result, only limited tests were conducted on these devices.

Federal Communications Commission FCC 08-260 
15 
propagation advantages of this spectrum will make it possible for WISPs and others to improve or extend 
their reach to customers in rural and other less densely populated area. We also anticipate that these new 
devices will have economic benefits for consumers and businesses by facilitating the development of 
additional competition in the broadband market. 
33. It is, of course, most important that we ensure that new unlicensed devices do not 
interfere with the incumbent licensed services in the TV bands. We now conclude that, with appropriate 
requirements and conditions on their operation, it is possible for both fixed and personal/portable low 
power devices to use the TV white spaces without disrupting the important television, public safety, and 
other services that use these frequencies. Because unlicensed broadband devices will share spectrum with 
broadcast TV and other licensed services, they will need the capability to avoid causing harmful 
interference to licensed services in the TV band. Specifically, an unlicensed device will need to be able to 
determine whether a TV channel or portion of a TV channel is unused before it transmits.38 Additionally, 
an unlicensed device will need features that enable it to avoid occupying a frequency band or to cease 
operation on a frequency when a licensed user commences transmission on a channel that was previously 
unused by a television band licensed service. The rules we are adopting will require that unlicensed 
TVBDs include these capabilities. 
34. The specific provisions of our plan for authorizing unlicensed TVBDs, including our 
decision to authorize these devices on an unlicensed basis, the requirements for fixed and 
personal/portable devices, methods and standards for protection of incumbent services, and the technical 
parameters for operation are described in the following sections; descriptions of the analyses and methods 
used in defining the operating characteristics of protected signals, the required minimum sensing 
capabilities, the permissible power levels, and the minimum distances that unlicensed devices must be 
from a licensed operation are also provided in the text below. The rules for these devices are set forth in 
Appendix B. 
A. Licensed vs. Unlicensed Operation 
35. In the Notice in this proceeding, the Commission proposed to allow low power devices to 
operate in the TV bands on an unlicensed basis.39 In their responses, a number of parties suggested that 
such devices should instead operate on a licensed basis. In the First R&O/Further Notice, we sought 
further comment on whether the proposed TV band devices should operate on an unlicensed, licensed, or 
hybrid basis.40 The record compiled in response to both the Notice and First R&O/Further Notice 
includes support for regulating TV band devices as unlicensed, licensed and a hybrid of the two 
approaches, as discussed below. 
36. A number of commenters submit that vacant spectrum in the TV bands should be 
licensed and that this regimen is necessary in order to enable the use of that spectrum for providing 
wireless broadband and mobile data services.41 These parties argue that companies need the assurance 
38 We note that the ability to make this determination is unrelated to the determination of whether a household is 
served or unserved for purposes of the Satellite Home Viewer Improvement Act. See 17 U.S.C.  119(a)(2)(B) 
and (d)(10). 
39 See Notice at  14. 
40 See First R&O/Further Notice at  26-32. 
41 See Charles L. Jackson and Dorothy Robyn (Jackson/Robyn) Further Notice comments at 26-32; Cox 
Broadcasting Further Notice comments at 6; Qualcomm Inc. Further Notice comments at 2; MSTV Further Notice 
reply comments at 31; FiberTower Corp. and the Rural Telecommunications Group, Inc. (RTG) ex parte comments 
at 4-10 (urging that the vacant TV band spectrum be licensed for fixed services to promote broadband deployment in 
rural areas and to meet the urgent need for wireless backhaul facilities); Sprint Nextel Corp. and T-Mobile USA, Inc. 
(continued.)

Federal Communications Commission FCC 08-260 
16 
that they will be entitled to protection from harmful interference before they will make the investments 
necessary to provide these services. They claim that licensing would encourage innovation because a 
licensee would receive all of the benefits of its innovation instead of having to share those benefits with 
others. Other parties continue to argue that this spectrum would be more effectively used on an 
unlicensed basis.42 For example, the NAF responds that the existing unlicensed bands have been used for 
a large number of innovative products, that innovation is encouraged by the low barriers to entry in an 
unlicensed regime, and that the TV bands have better propagation properties than currently available 
unlicensed bands, which would cause innovation to flourish.43 It further states that many unlicensed uses 
such as community networks and rural service do not require a large infrastructure investment, so 
licensing is not needed to ensure the provision of service. Tropos Networks adds that the expense of 
acquiring licenses can make providing wireless broadband services prohibitive in rural and Native 
American tribal areas.44 Those supporting the licensed and unlicensed approaches argue a number of 
additional points and counter points as described below. 
37. Jackson/Robyn argue that the TV bands are not well suited to the low-power uses 
planned by unlicensed advocates.45 They contend that under an unlicensed approach, devices would 
likely have to operate in 6 megahertz channels  which are far smaller than the available bandwidth in the 
2.4 GHz or 5.0 GHz unlicensed bands  because the TV band white spaces occur in 6 megahertz 
increments. Jackson/Robyn further argue that the use of this spectrum for low-power unlicensed devices 
would fail to take advantage of the better propagation properties of the TV bands compared to those of 
higher frequencies and to exploit the capability that it is easier to manufacture equipment that generates 
significant power in the TV bands than at higher frequencies.46 The White Space Coalition disputes these 
views, arguing that Jackson/Robyns claim that the TV band is not suited to unlicensed uses is premised 
on the assumption that future unlicensed uses will be identical to the current uses of those unlicensed 
(Continued from previous page) 
ex parte comments; National Telecommunications Cooperative Association ex parte comments; GE Healthcare ex 
parte comments; CTIA ex parte comments at 2 (suggesting that the Commission adopt a licensing approach while 
reserving a portion of the TV band spectrum for future unlicensed use); CTIA and Rural Cellular Association ex 
parte comments at 2-4; Comptel, RTG, Sprint Nextel Corp., FiberTower Corp. ex parte comments (suggesting that 
vacant TV band spectrum be licensed for fixed services using the Commissions Part 101 rules) and the Wireless 
Internet Service Providers Association ex parte presentation July 31, 2008 at 7. 
42 See White Space Coalition Further Notice comments at 21-23; IEEE 802.16 Further Notice comments at 5; NAF 
Further Notice comments at 9-58; and Tropos Networks Further Notice at 5. 
43 See NAF et al. Further Notice comments at 42. NAF also contends that under the First Amendment the 
Commission has no right to prevent people from speaking via the use of radio communications by requiring 
exclusive licensing where the threat of interference does not exists. Id. at 53-58. 
44 See Tropos Networks Further Notice comments at 4. 
45 See Jackson/Robyn Further Notice comments at 24-25. 
46 Id. at 24. See also FiberTower Corp. and RTG ex parte comments at 16-17; CTIA ex parte comments at 15-16. 
Jackson/Roberts also hypothesize that low-power personal devices such as those the unlicensed advocates envision 
could be supported under a licensed model. They state that device manufacturers could contract with a licensee to 
allow consumers who purchase the devices to use them in the white space spectrum. Jackson/Robyn Further Notice 
comments at 6. NAF argues that no manufacturer has expressed an interest in such an arrangement, licensees would 
avoid such an arrangement because it would be difficult for them to prevent unauthorized use of their spectrum, and 
consumers would be limited to buying equipment from a single manufacturer (instead of the large number of 
choices, for example, available with Wi-Fi). NAF Further Notice comments at 40.

Federal Communications Commission FCC 08-260 
17 
bands.47 It contends that the better propagation properties of the TV bands would make it likely that new 
unlicensed applications would be developed in the future that would not be possible in other bands. 
38. Supporters of a licensed approach also hold that there is no need for additional spectrum 
for unlicensed devices. In this regard, Qualcomm submits that there is no evidence that consumers have 
had to return unlicensed devices because the unlicensed spectrum is too crowded.48 The Association for 
Maximum Service Television and the National Association of Broadcasters, in joint comments 
(MSTV/NAB), add there is over 100 megahertz of unlicensed spectrum below 2 GHz and that 255 MHz 
of spectrum in the 5 GHz band was made available for unlicensed use in 2003 and so there is plenty of 
spectrum available for unlicensed use.49 The White Space Coalition counters these arguments, stating 
that the propagation characteristics of the TV band are superior to the other unlicensed bands for many 
applications and that none of the other unlicensed spectrum is below 900 MHz.50 
39. Some commenters claim that a large amount of revenue could be generated for the U.S. 
Government by auctioning licenses for the TV band whitespaces.51 Based on the value of recent 
transactions in the 2.5 GHz BRS/EBS band, Jackson/Robyn give an estimate of $3.7 billion to $6 billion 
for the TV white spaces. Commenters supporting an unlicensed approach argue that Jackson/Robyns 
estimates of auction proceeds are over-inflated. NAF states that the uncertainty for bidders in this band 
with respect to the availability of spectrum would be huge.52 It observes that there are currently over 
5000 low power TV and TV translator stations that have no post-DTV spectrum assignment yet. It 
further points to the fact that low power auxiliary stations such as wireless microphones have the right to 
transmit in the whitespaces on any unoccupied TV channel in a possibly wide geographic area. NAF also 
argues there would be high transaction and coordination costs in using the licensed white spaces because 
the operating parameters will be different everywhere and that this would further depress the value of the 
white space spectrum.53 
40. Jackson/Robyn claim that licensed use of the TV band would allow up to 50% more of 
the TV band to be used by TV band devices than unlicensed use would afford.54 According to 
Jackson/Robyn, this efficiency would come from two sources. First, they submit that the use of 
directional antennas and power control would enable licensees to operate devices up to the edge of a TV 
stations Grade B/noise-limited contour, whereas unlicensed use of the band would require a buffer zone 
from 17-46 miles to ensure that unlicensed devices do not interfere with TV receivers within the stations 
service contour. Secondly, they submit that licensees would be able to negotiate with TV broadcasters to 
relax the interference requirements in individual situations, and thereby allow greater use of the white 
spaces. Jackson/Robyn state that if the Commission would allow TV band device licensees to negotiate 
47 See White Space Coalition Further Notice comments at 25. 
48 See Qualcomm Inc. Further Notice comments at 6. 
49 See MSTV/NAB Further Notice comments at 38. FiberTower Corp. and RTG ex parte comments at 16. 
50 See White Space Coalition Further Notice comments at 23. 
51 See Jackson/Robyn Further Notice comments at 56-57; MSTV/NAB Further Notice reply comments at 32-33. 
FiberTower Corp. and RTG ex parte comments at 24-26. 
52 See NAF et al. Further Notice comments at 47-50. 
53 The National Telecommunications Cooperative Association believes that the unused TV band spectrum should be 
licensed but not auctioned because the resources of rural carriers are better spent on providing services rather than 
on buying spectrum. See National Telecommunications Cooperative Association ex parte comments. 
54 See Jackson/Robyn Further Notice comments at 15-16.

Federal Communications Commission FCC 08-260 
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interference rights with broadcasters, the use of the television bands could evolve over time to more 
efficient uses as market conditions and technology change dictate.55 According to NAF and the White 
Space Coalition, Jackson/Robyns claims in this regard are not valid since there is no reason to believe 
that licensed devices will be able to operate any closer to broadcasters Grade B contours than unlicensed 
devices because the same interference protection would have to be provided to broadcasters in either 
case.56 Furthermore, NAF states, allowing broadcasters to negotiate to allow greater interference from 
white space devices would be contrary to broadcasters public interest obligations to provide free TV 
service to viewers because some TV viewers would lose the ability to receive over the air TV service. 
41. MSTV/NAB are concerned about possible interference to TV broadcasters from 
unlicensed devices.57 They submit that if unlicensed devices were to cause interference to TV reception, 
it would be impossible to track down the source of the interference.58 They further argue that, as 
experience with other unlicensed uses has shown, modified devices and nonconforming amplifiers and 
directional antennas would be sold that would allow unlicensed devices to cause greater interference than 
allowed under the rules that the Commission adopts.59 MSTV/NAB state that a licensed regime would 
provide accountability for interference in that the licensee would be responsible for any interference that 
occurs. They submit that the identity of the licensee would be a matter of public record so the party 
responsible for resolving the interference could be easily located. Jackson/Robyn submit that the 
infrastructure-based architecture that licensees would be most likely to deploy would reduce the 
probability of interference compared to low-power unlicensed devices.60 On the other hand, the White 
Space Coalition states that the parameters it has proposed for unlicensed operation would allow 
unlicensed devices to avoid interference to broadcasters and avoid transmitting at maximum powers.61 
42. A number of parties, including the WISPA, support using a hybrid or light licensing 
model rather than an exclusive licensing model.62 They suggest an approach that would be similar to the 
Commissions rules for non-exclusive licensing of the 3650-3700 MHz band.63 Under their plan, fixed 
base stations would be registered in a database and registrants would not have exclusive use of the 
55 Id. at 49-50. 
56 See NAF et al. Further Notice technical reply comments at 12; the White Space Coalition Further Notice 
comments at 19, 23. 
57 See MSTV/NAB Further Notice comments at 2-5. See also FiberTower Corp. and the RTG ex parte comments at 
18-21 (Overcrowding and interference would be much worse in the TV white spaces because of the excellent 
propagation characteristics.); CTIA ex parte comments at 2-3; CTIA and Rural Cellular Association ex parte 
comments at 4-5. 
58 See MSTV/NAB Further Notice reply comments at 31-32 noting that interference is avoided in 2.4 GHz band by 
the fact that the propagation distances are short so in effect property owners are acting as their own interference 
coordinators. They state that the propagation properties of the TV band are such that this will not be the case in 
unlicensed white space operation. 
59 See MSTV/NAB Further Notice comments at 30. 
60 See Jackson/Robyn Further Notice comments at 41. 
61 See White Space Coalition Further Notice reply comments at 4-16. 
62 See Nextwave Broadband Inc. reply comments at 2-3; IEEE 802.16 comments at 5 (IEEE would prefer a 
completely unlicensed approach but supports a hybrid scheme as an acceptable and viable alternative), WISPA ex 
parte presentation of July 31, 2008 at 7-16. 
63 The rules for licensed operation in the 3650-3700 MHz band on a non-exclusive basis are set forth in 
47 C.F.R.  90.1301-.1337.

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spectrum. These parties suggest that a database system would aid in the resolution of interference 
problems among the registered users by allowing potential sources of interference to be identified. 
Supporters of a hybrid approach argue that this plan would present a low barrier to entry, so that 
innovative low-cost use of the spectrum would still be possible. 
43. In their Petition for Reconsideration, NAF/CUWN argues that the Commission should 
restore its previous tentative conclusion in favor of unlicensed use that was set forth in the Notice in this 
proceeding.64 They argue that the Commission provided no explanation for its change of course to give 
consideration to licensing use of the TV white spaces. 
44. Discussion: As we stated in the First R&O/Further Notice, our goal in this proceeding is 
to allow new uses of radio on unused television channels at locations where such operations will not 
result in harmful interference to, or disrupt, TV and other authorized services.65 For the reasons discussed 
below, we conclude that it is in the public interest to allow TV band devices to operate in these bands on 
an unlicensed basis pursuant to restrictions carefully designed to protect users of incumbent licensed 
services. This approach permits us to introduce new innovative uses while protecting the continued 
operation and growth of the TV broadcast and other authorized services in these bands. Because 
unlicensed operations are not allowed to cause interference to authorized services, the interference 
protection status of existing services operating in these bands will not be affected, consistent with the 
Commissions goals in this proceeding. 
45. The record developed in response to the Notice and First R&O/Further Notice indicates 
that there is a need for additional spectrum for unlicensed broadband devices, particularly in the lower 
frequency bands. A number of WISPs have noted that the TV frequencies would provide improved signal 
coverage over other unlicensed bands, including improved in-building penetration properties which other 
unlicensed bands lack. We disagree with Jackson/Robyn that the 6 megahertz size of TV channels and 
propagation characteristics of these bands make them inappropriate for unlicensed use. Unlicensed 
devices will not be limited to 6 megahertz bandwidth, as they will be allowed to operate across multiple 
channels in locations where the bandwidth is available. The signal coverage afforded by the propagation 
characteristics of this spectrum is also desired by proponents of unlicensed devices in that it will facilitate 
the provision of improved and/or more economical wireless Internet service to consumers, particularly in 
rural areas where transaction costs may be higher than elsewhere. Further, as argued by comments filed 
by the White Space Coalition and other parties who have expressed interest in developing or operating 
low power devices in these bands, other innovative uses for this spectrum may emerge once it is made 
available for unlicensed use. 
46. While we recognize the arguments in the record in support of a licensed approach for 
making the TV white space spectrum available for new uses, we conclude that such an approach is not 
practicable for many kinds of devices that could use these bands, and thus would reduce the benefits 
available. As we noted in the First R&O/Further Notice, a licensed model tends to work best when 
spectrum rights are clearly defined, exclusive, flexible and transferable.66 When spectrum rights lack 
these attributes, potential licensees face uncertainty and may lack incentives to invest in a license or offer 
service. We conclude that attributes supporting the successful use of licensing would be difficult to 
accomplish here, particularly if we want to maintain our stated goal of not affecting the interference 
protection status of existing services. The frequencies and amount of unused TV band spectrum will vary 
from location to location and could change over time as additional television stations and other primary 
64 See Notice at  14-16. 
65 See First R&O/Further Notice at  1. 
66 Id. at  27.

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and secondary operations are licensed or as existing operations change frequency. For example, the 
assignment of channels for digital operation to low power television stations is not scheduled to be 
complete by the end of the DTV transition in February 2009. Also, currently authorized DTV stations 
have recently been permitted to submit applications asking to modify their facilities and/or change 
channels.67 These changes could complicate licensing of the white spaces spectrum, particularly if the 
Commission were to license the spectrum pursuant to auction. Because we have decided to require that 
TV band devices protect other types of licensees in the bands, a licensed TV band device could 
potentially lose its ability to operate on some, or even all, of its authorized frequencies when new 
operations with higher allocation status are authorized to operate in the same area.68 
47. As discussed below, we are adopting a number of requirements for TV band devices that 
will significantly reduce the potential for these devices to cause harmful interference to authorized 
services and will make it possible to identify the source of any interference that might occur. In 
particular, TV band devices will be allowed to operate only after they have identified which channels in 
their area are available for their use. To ensure that devices adhere to this requirement, we are requiring 
that fixed and personal/portable TV band devices that do not operate in client mode to access a central 
database system and that fixed devices register with the database system. Registration of fixed TV band 
devices will facilitate locating the source of an interference problem should it occur from these higher 
power devices. We are not requiring registration of personal/portable devices, as the lower operating 
power and non-directional antennas of personal/portable devices will limit the potential interference range 
of those devices to the immediate vicinity of a device. We are also concerned that a registration 
requirement for personal/portable devices could significantly limit the types of devices that could operate 
by necessitating that a device includes the capability to input alphanumeric data. Thus, this scheme 
addresses the interference concerns of those commenters who support licensing of TV band devices. 
48. With regard to the argument that a licensing regime would encourage investment in the 
provision of services using wireless spectrum, we observe the stability normally provided by exclusive 
licensing would be difficult to achieve for TV band device operation. To avoid affecting the interference 
protection status of incumbent services, the licenses here would afford no right to interference-free 
operation. Instead, the licensee would merely have the right to operate on those television channels that 
are not currently in use by other higher-priority users. The specific channels and amount of available 
spectrum available at a given location could change over time as additional television channels are 
67 On August 3 2004, the Commission imposed a freeze on the filing of certain requests for changes to TV and DTV 
channels and service areas. See Public Notice, Freeze on the Filing of Certain TV and DTV Requests for 
Allotment or Service Area Changes, 19 FCC Rcd 14810, 14810-11 (2004) (August 2004 Filing Freeze PN). This 
freeze was imposed prior to the commencement of the channel election process, in order to provide a stable database 
for developing the post-transition DTV Table. The freeze precluded parties from filing the following: (i) petitions 
for rulemaking to change DTV channels within the current DTV Table; (ii) petitions for rulemaking to establish a 
new DTV channel allotment; (iii) petitions for rulemaking to swap in-core DTV and NTSC channels; 
(iv) applications to change DTV channel allotments among two or more licensees; (v) petitions for rulemaking by 
licensees/permittees to change NTSC channels or communities of license; (vi) applications to maximize DTV or 
analog TV facilities; and (vii) certain Class A television station applications. The freeze did not prevent the 
processing of pending applications. See id.; see also 47 C.F.R.  73.1690, 73.3533, 73.3538. On May 30, 2008, 
the Commission lifted this freeze. That action effectively allowed stations to file applications for maximization of 
their facilities and any desired channel changes, immediately and the Commission encouraged stations to file 
promptly. That action did not, however, lift the current freeze on filing of petitions for allotment of DTV channels 
for new stations, or for changes in community of license. See Public Notice, Commission Lifts the Freeze on the 
Filing of Maximization Applications and Petitions for Digital Channel Substitutions, Effective Immediately, DA- 
1213, released May 30, 2008. 
68 See First R&O/Further Notice, at  14.

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allocated, as low power auxiliary devices make use the channels, and the other services that use these 
bands similarly initiate new or modify existing operations. Hence, we do not believe that the issuance of 
licenses would necessarily provide the benefits that the proponents of licensing claim because of the 
tenuous nature of the rights that would actually be granted by the license. Furthermore, there has been 
tremendous growth in the development of new technologies and the introduction of new services that rely 
on unlicensed devices, which belies the assertion that a licensing regime is needed to encourage 
investment in spectrum development. 
49. We are also not persuaded by other arguments raised in support of a licensing regime for 
TV band devices. We note that a number of parties draw attention to the potential revenue that could be 
raised by auctioning the unused television bands under a licensing regime. We believe that these 
arguments are misplaced and do not address our goal in this proceeding, which is to allow new uses on 
unused television channels in locations where such operations will not result in harmful interference to or 
disrupt TV and other authorized services. Thus, the regulatory model used here must be appropriate to 
facilitate new uses while protecting the various types of incumbent uses, not chosen merely because it 
could provide revenue from auctioning licenses. We are also not persuaded by Jackson/Robyns claim 
that licensing TV band devices would allow the television bands to be used more efficiently  i.e., 
licensed users could negotiate interference protection arrangements and thus increase the use of available 
spectrum for TV band devices, which in turn would allow the use of the bands to evolve over time to 
more efficient uses as market conditions and technology change dictate. As discussed above, licensing 
TV band devices is not practicable while also protecting the present and future use of the band for 
broadcasting and other incumbent uses. Allowing licensed TV band devices to negotiate interference 
requirements with licensed users as Jackson/Robyn suggest would signal a fundamental shift from our 
stated goal to avoid disruption of TV and other authorized services by TV band devices. 
50. We also find that a hybrid licensing scheme such as that which the Commission adopted 
in the 3650 MHz proceeding would not be appropriate here.69 In the 3650 MHz band, the Commission 
decided to issue non-exclusive licenses for stations providing fixed and mobile service. These 3650 MHz 
stations will be registered in a database which will aid the licensees in resolving interference problems 
among themselves by allowing them to identify potential sources of interference. However, because that 
band is allocated to the fixed and mobile services on a primary basis, the registered stations have no 
interference protection from existing stations of those services in the band. Although the 3650 MHz fixed 
and mobile stations must protect the previously existing satellite earth stations operating in that band, 
satellite earth station licenses in the band issued after 2000 are secondary and therefore have no right to 
interference protection from the new fixed and mobile stations.70 The situation in the TV bands is 
different. Here, future broadcast uses of the television band will have the right to interference protection 
from TV band devices. Not only must future primary use of the band by broadcasters be protected, but 
secondary uses such as low power auxiliary devices and broadcast auxiliary service (BAS) must also be 
protected. Thus, although the non-exclusive licensing approach would address the interference status 
among TV band devices, it would not resolve the interference rights between TV band devices and other 
licensed users in the bands. We find that unlicensed operation under Part 15 of our rules is a better fit for 
TV band devices because Part 15 devices must not cause harmful interference to licensed users, whether 
primary or secondary. Accordingly, we will authorize new devices on vacant spectrum in the TV bands 
on an unlicensed basis. Such use will be allowed under the rules discussed in the following sections. 
69 See Wireless Operations in the 3650-3700 MHz Band, ET Docket No. 04-151, Report & Order, 20 FCC Rcd 
6502 (2005); see also Rules for Wireless Broadband Services in the 3650-3700 MHz Band, WT Docket No. 05-96; 
Additional Spectrum for Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380, 
Memorandum Opinion and Order, 22 FCC Rcd 10421 (2007). 
70 Id. at  7.

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51. With respect to NAF/CUWNs request that we reconsider our decision to reopen the 
issue of whether use of the TV white spaces should be allowed on a licensed or unlicensed basis, we note 
that, notwithstanding the petitioners argument that this issue had been decided, the Commissions 
position on this issue in the Notice was that of a proposal, not a final decision, and it requested comment 
on that proposal and its tentative conclusions favoring unlicensed use. 71 The Commission decided to 
request additional comment on this question in the First R&O/Further Notice after some parties 
responding to the Notice suggested that this spectrum should be assigned on a licensed basis. 
Specifically, in the First Report and Order, the Commission sought comment on whether the proposed 
low power operations in the TV bands should be allowed on a licensed, unlicensed, or hybrid basis in the 
interest of obtaining a further record on this issue. We find nothing arbitrary or otherwise inappropriate in 
that action. Accordingly, we are denying NAF/CUWNs request that we reverse our decision to seek 
further comment on the issue of whether to allow low power devices to operate in the TV white spaces on 
a licensed or unlicensed basis. 
B. Plan For Unlicensed Use Of The TV Bands 
52. As we observed in the Notice, the development of industry standards for broadband 
unlicensed devices in other frequency bands has enabled the introduction of a host of new unlicensed 
wireless broadband products that can be divided into two distinct types of operations.72 The first type of 
operation involves the provision of broadband services to homes and businesses. This type of operation 
uses higher power, is primarily fixed and operated outdoors, may cover a substantial geographic area, and 
may be part of a service infrastructure. In this regard, Wireless Internet Service Providers (WISPs) are 
now using unlicensed devices to provide broadband service on a point-to-point basis over distances of 
several kilometers. The second type involves wireless portable computing devices, such as laptops and 
personal digital assistants (PDAs), wireless home and local area networks (LANs), and other short-range 
applications within a home or a business. Unlike the first type of operations, these personal/portable 
devices generally transmit with very low power and are used indoors or within a small localized area. 
Portable devices can be used for: broadband wireless connectivity between a cable modem, DSL modem, 
or other internet connection and in-home computing devices; broadband wireless home entertainment 
applications, such as video/home theater use; business applications such as wireless inventory control and 
wireless cash registers; and personal applications such as wireless headphones. Fixed and 
personal/portable operations may also be used together. 
53. For the purpose of developing operating rules and interference protection criteria, we are, 
as proposed, classifying the unlicensed broadband devices to be used in the TV bands into these two 
general functional categories. The first category will consist of higher power fixed unlicensed devices 
that are operated from an installed outdoor location that does not change and may be used to provide a 
commercial service such as wireless broadband Internet access (non-commercial operations will also be 
permitted). The second category will consist of lower power personal/portable unlicensed devices, 
such as Wi-Fi-like cards in laptop computers or wireless in-home LANs. We find that both of these types 
of devices can be accommodated in the TV spectrum if they comply with appropriate regulatory measures 
to ensure that their operations are limited to TV channels where interference will not result. Both types of 
devices will be allowed to transmit broadband data as well as other types of communications. 
54. We recognize that different measures are appropriate for achieving those protections 
from the two types of devices, given the differences in their uses and interference potential. Therefore, as 
discussed below, we are adopting different interference avoidance requirements for fixed and 
personal/portable unlicensed devices. In addition, we are providing for operation of personal/portable 
71 See Notice at  16. 
72 See Notice at  18.

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devices under two different modes: 1) controlled by a fixed device or a Mode II personal/portable device 
and 2) independent. In each of these cases, our goal is to make the technical requirements as simple and 
as reliable as possible. We believe that this approach will provide flexibility to permit a wide range of 
unlicensed broadband uses and applications and while ensuring that the most appropriate and effective 
mechanisms are in place to protect TV and other licensed services. One of the most important factors in 
avoiding interference is how to reliably determine the channels that are unused at the location of an 
unlicensed device. That subject has been a major issue between the incumbent licensed services and the 
proponents of unlicensed devices. We will first discuss our decision with respect to the methods for 
determining which channels are occupied at a given location and then address the basic elements of plans 
for operation of fixed and personal/portable device. 
1. Methods For Determining Occupied And Unoccupied Channels 
55. With the technologies currently available, there are three principal methods that could be 
used to determine whether a portion of the TV band is unused at a specific time and/or location. The first 
approach involves determining the location of an unlicensed device and then accessing a database of 
licensed services to identify active services at that location. The devices location could be determined by 
a professional installer or by a geo-location technology, such as GPS, incorporated within the device. 
Once the devices location is known, an analysis would be performed for each channel using either an 
internal or external database to determine whether the unlicensed device is located far enough outside the 
protected service contours of licensed stations to avoid causing harmful interference. This would yield a 
list of available channels on which the unlicensed device could choose to operate. 
56. A second method would be for an unlicensed device to receive information transmitted 
on a control signal by an external source, such as a broadcast station, CMRS base station, or another 
unlicensed transmitter, indicating which channels are available at its geographic location. Under the 
control signal method, a device would be allowed to transmit only after it receives a signal with 
information that positively identifies which TV channels are available for use. Control signals could be 
transmitted by any number of sources, such as broadcast TV and radio stations and/or licensed wireless 
communications providers. 
57. A third method would be to incorporate spectrum listening or sensing capabilities in 
the unlicensed device to detect whether other transmitters are operating in an area. For example, a fixed 
unlicensed transmitter could incorporate an antenna and a receiver capable of detecting signals down to a 
certain threshold level that would be the standard for determining if a particular TV channel is actually in 
use. Generally, such sensing would have to be much more sensitive than the receivers used in the 
licensed service.73 The sensing function would examine each channel and those channels on which it 
detected no signals above the threshold would be considered available for operation, subject to any 
additional limitations that might be appropriate. If signals were detected above the threshold on a 
particular channel, that channel would not be eligible for operation. As the Commission has previously 
noted, there are techniques that can be used to increase the ability of a sensing receiver to reliably detect 
73 Spectrum sensing is also susceptible to a potential shortcoming that is sometimes referred to as the hidden node 
problem. In the case of unlicensed devices in the TV band, this problem could arise when there is signal blockage 
between the unlicensed device and a TV station, but no blockage between the TV station and a TV receiver and no 
blockage between the unlicensed device and the same TV receiver. In such a case, the sensing receiver in the 
unlicensed device may not detect the presence of the TV signal because it is blocked, and the unlicensed device may 
therefore commence transmissions on an occupied channel, thus causing interference at the TV receiver. See ex 
parte presentation by Shared Spectrum Company in ET Docket No. 02-380, on September 29, 2003.

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other signals in a band which rely on the fact that it is not necessary to decode the information in a signal 
to determine whether a signal is present.74 
58. In the Notice, the Commission proposed to require that fixed unlicensed TV band devices 
incorporate a geo-location method such as a GPS receiver and that they access a database to identify 
vacant channels at their location.75 To ensure that fixed/access devices operate only on unused TV 
channels, it proposed to require that such devices incorporate a method for determining geographic 
location with a minimum accuracy of 10 meters. Alternatively, the Commission proposed to allow fixed 
unlicensed devices to be professionally installed by a party that would determine a devices geographic 
location and contact the database system to determine the available unused channels at that location. It 
further proposed to require that personal/portable devices operate only when they receive a control signal 
from a source such as an FM or TV station or a CMRS provider that identifies the vacant TV channels in 
that particular area.76 The Commission also sought comment on the possibility of using spectrum sensing 
to identify vacant TV channels, but did not propose any specific technical criteria for that method.77 
59. In the First R&O/Further Notice, the Commission sought additional comment and 
information on issues related to the appropriate geo-location method, including the means by which 
devices employing the geo-location/database approach would protect certain authorized services, such as 
wireless microphones, the location of which may not be included in the databases.78 The Commission 
also recognized that a number of parties suggested that spectrum sensing could be used to identity TV 
channels that would be available for use by unlicensed TVBDs, but noted that no party had provided 
sufficient technical information for it to adopt rules. The Commission therefore sought comment on 
whether unlicensed TV bands devices should be allowed to use spectrum sensing as a means to determine 
the availability of unused frequencies in the TV bands, and, if so, the technical features and parameters of 
the sensing capability to be required.79 It also requested comment on whether devices should be permitted 
to rely on spectrum sensing as the sole means of identifying vacant channels, or whether a device should 
be required to use both geo-location and spectrum sensing to identify vacant channels at its location.80 In 
considering the spectrum sensing approach, the Commission did observe that some parties responding to 
the Notice raised concerns about whether a GPS receiver incorporated in a TV band device would be a 
reliable method for performing geo-location because it may not work indoors or at outdoor locations 
where the GPS signal is obstructed.81 
74 For example, a TV band spectrum sensing function could be made more sensitive, i.e., made to detect lower signal 
levels, by using bandwidths much smaller than a 6 MHz TV channel and/or looking for specific features of the TV 
signal such as the pilot for digital TV or the visual and audio carriers for analog TV. See Notice of Proposed Rule 
Making and Order in ET Docket No. 03-108, 18 FCC Rcd 26859 (2003). 
75 See Notice at  26. 
76 Id. at  21. 
77 Id. at  20. 
78 See Further Notice at 12285. 
79 Id. at  33. 
80 Id. at  30. 
81 See NAB/MSTV Further Notice comments at 14, IEEE 802 comments at 8, and Society of Broadcast Engineers 
Further Notice comments at 3.

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60. A number of the comments received in response to the First R&O/Further Notice support 
the use of a geo-location/database approach for fixed TV band devices.82 Those supporting the geolocation/
database approach generally state that this method would provide a means to reliably determine 
occupancy of TV channels by fixed services, but acknowledge that it does not provide for identifying 
channel occupancy by portable and/or intermittent services such as wireless microphones. MSTV/NAB 
claim that use of geo-location coupled with a database is the only way to ensure that television stations 
are protected from interference from TV band devices. Motorola notes that the geo-location/database 
approach offers flexibility for protection of licensed services as it would allow the restricted radius around 
TV stations and other protected coverage areas to be changed without changing the TV band devices.83 
Motorola believes that the same general techniques that allow fixed devices to operate in the TV bands 
can also work for personal/portable deployment. It states that an anchor personal/portable or fixed 
device could use geo-location and database techniques to determine its location and send an enabling 
signal to associated personal/portable devices.84 
61. In addition, Motorola believes that the database should be flexible enough to vary the 
applied protection levels depending on the transmit power of the TV band device since the interference 
potential of TV band devices will vary with transmitted power. It submits that officially established 
protection levels should be contained in the database to make sure that consistent calculations are 
performed by various manufacturers equipment. Motorola also supports the Commissions suggestion 
that a private party be engaged to develop and maintain such a database.85 The Communications 
Research Centre Canada (CRCC) describes a geo-location method that it states will work indoors, in 
which a TV band device determines its position by identifying the DTV stations that can be received at its 
location.86 
62. IEEE 802, Intel, Josephson Engineering, Motorola, and the NAF all believe that the 
proposed 10 meter accuracy requirement is more stringent than necessary.87 IEEE 802 recommends an 
accuracy standard of 30 meters as being comparable to that required by the Commission for fixed 
stations. Intel recommends an accuracy standard of 100 meters, stating that this distance is a small 
fraction of the required protection distance from TV stations. Motorola similarly recommends an 
accuracy of 100 meters because TV signal strength varies only a fraction of a dB over this distance. The 
NAF recommends 100-200 meters on the basis that this range is consistent with the accuracy of station 
82 The geo-location/database method is supported by the American Society for Healthcare Engineering of the 
American Hospital association (Further Notice comments at 5-6), Communications Research Centre Canada 
(Further Notice comments at 1), IEEE 802.18 comments at 21, Motorola Further Notice comments at iii and reply 
comments at 5-6, MSTV/NAB Further Notice reply comments at 16-17, NCTA (Further Notice comments at 6), 
and the WISPA (Further Notice reply comments at 3). 
83 See Motorola Notice reply comments at 6. 
84 See Motorola Further Notice reply comments at 6. 
85 See Motorola Notice comments at 20. 
86 See Communications Research Centre Canada Notice comments at 1. 
87 See IEEE 802 Notice comments at 9, Intel Notice comments at 19, Motorola Notice reply comments at 8 and NAF 
Notice reply comments at 24.

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coverage predictions.88 Commenting parties generally believe that the Commission should not require the 
use of a specific geo-location method such as GPS.89 
63. The NCTA suggests that rather than requiring Internet access in order for the TV band 
device to access the database, each television broadcaster could transmit a portion of the database to the 
TV band device.90 Nextwave Broadband supports registration of the location of unlicensed TV band 
devices in the database as a means to facilitate coordination among the users of these devices and to allow 
for monitoring of spectrum usage.91 IEEE 802.18 believes that fixed TV band base stations should be 
professionally installed, with site surveys, propagation/coverage predictions, and geo-location of the base 
station.92 The White Space Coalition submits that outdoor devices could incorporate a GPS capability in 
lieu of professional installation.93 Other parties raised questions about who should be considered a 
professional installer.94 
64. Several parties express reservations about the use of a geo-location/database approach. 
The NAF and the White Spaces Coalition are concerned that requiring use of a database will increase 
costs by increasing the complexity of the TV band devices and requiring payments to a third party to 
develop and maintain the database.95 Tropos Networks argues that no complete and accurate database of 
broadcast operations currently exists and that the costs of developing one and the associated 
computational software would be large.96 WISPA believes that the wireless Internet service provider 
market is too dynamic for a registration scheme to ever be current and accurate.97 These parties also 
reiterate their previous concerns that GPS does not function reliably indoors.98 For example, the White 
Space Coalition believes that requiring use of a geo-location/database approach would eliminate the 
flexibility to create decentralized networks and would restrict indoor use of TV band devices, as 
unassisted GPS does not function indoors.99 Shure, Inc. notes that a database would not protect wireless 
microphones as these devices are portable and often moved on short notice.100 Advance Broadband 
contends that a geo-location/database approach would not be effective because consumers would override 
88 See IEEE 802 Notice comments at 9, Intel Notice comments at 19, Josephson Engineering Notice comments at 4, 
Motorola Notice reply comments at 8 and NAF Notice reply comments at 24. 
89 See Intel Notice comments at 19, Josephson Engineering Notice comments at 3, Motorola Notice reply comments 
at 8 and NAF Notice reply comments at 24. 
90 See NCTA Notice reply comments at 13-14. 
91 See Nextwave Broadband Notice comments at 5. 
92 See IEEE 802.18 Notice comments at 21. This approach requires that each DTV station transmit a unique 
identification code or watermark that can be detected by the TV band device. 
93 See White Space Coalition Notice comments at 10. 
94 See Tropos Notice comments at 4 and Harris Notice comments at 8. 
95 See Coalition Notice comments at 10; NAF Notice technical comments at 13. The NAF believes that use of geolocation 
and a database should not be required, but instead should be one option of several possible ways TV band 
devices could avoid interference. NAF Notice comments at 69. 
96 See Tropos Networks Notice comments at 12. 
97 See WISPA Notice comments at 3. 
98 See Coalition Notice comments at 10 and Thomas C. Smith Notice comments at 10. 
99 See White Space Coalition Notice comments at 9-11. 
100 See Shure Notice comments at 10.

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or disable it or that the equipment might malfunction and result in interference to broadcasters.101 WISPA 
argues that use of a database isnt appropriate because it wouldnt take into account attenuation of the 
signal from the TV band device due to vegetation, buildings, or terrain.102 
65. Other comments express support for use of the spectrum sensing method to determine 
available channels.103 Supporters of spectrum sensing submit that signal detectors in the TV band are 
capable of high degrees of detection sensitivity and can detect and avoid broadcast signals that have 
undergone high attenuation in a hidden node situation.104 They further state that spectrum sensing can 
protect incumbent licensees and facilitate spectrum sharing with other low power devices in the TV white 
spaces and would be more cost effective and efficient than the geo-location/database approach.105 Several 
parties argue that spectrum sensing alone is adequate to determine when a TV channel is available. In 
statements representative of these parties positions, the White Space Coalition argues that spectrum 
sensing does not depend on third party assisting technologies such as databases of available channels and 
would better facilitate the creation of a mass market for devices. It claims that spectrum sensing is a 
proven, well understood technique and that the concern raised by incumbent licensees that this approach 
is unproven is simply not the case.106 NAF argues that spectrum sensing shows great promise, would be 
cost effective to implement, and that detectors in TV band devices are capable of high degrees of 
sensitivity and can detect and avoid signals that have undergone 37 dB of attenuation due to the hidden 
node problem.107 Tropos Networks states that spectrum sensing could be used in both fixed and 
personal/portable devices.108 WISPA believes that a distributed sensing model, whereby interconnected 
devices would share sensing information, would be far superior to geo-location, especially over time as 
the number of sensors in an area increases.109 
66. The White Space Coalition argues that the Commission should allow personal/portable 
devices that rely on spectrum sensing alone to determine when a channel is vacant. It argues that 
spectrum sensing will protect incumbent licensees and facilitate spectrum sharing with other low power 
devices in the white spaces, while avoiding the operational difficulties and economic burdens associated 
with the other interference avoidance mechanisms identified in this proceeding. The White Space 
Coalition states that because spectrum sensing does not depend on third-party assisting technologies such 
as databases of available channels or broadcast beacons to implement, a spectrum sensing approach 
would better facilitate the creation of a mass market for devices, resulting in more affordable consumer 
101 See Advanced Broadband Notice comments at 4. 
102 See WISPA Notice comments at 2. 
103 The spectrum sensing method is supported by CEA (Further Notice comments at 3-5), the White Space Coalition 
(Further Notice comments at 5-7), NAF, et al. (Further Notice comments at 63-67), and Tropos Networks (Further 
Notice comments at 10). 
104 See for example, NAF, et al. Notice comments at 63-64. A hidden node is a location where an obstruction is 
present between the sensing receiver and the signal to be detected. In this case, the sensing receiver may fail to 
detect that a channel is occupied and begin transmitting, thus causing interference to other nearby parties attempting 
to receive that channel along an unobstructed path. 
105 See for example, NAF, et al. Notice comments at 65 and White Space Coalition Notice comments at 3. 
106 See White Space Coalition Further Notice comments at 3-4. 
107 See NAF Further Notice comments at 65-66. 
108 See Tropos Networks Further Notice comments at 10. 
109 See WISPA Further Notice comments at 3.

Federal Communications Commission FCC 08-260 
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products and more attractive prospects for wireless broadband, including in rural areas.110 The NAF and a 
number of consumer and public interest groups believe that the Commission should authorize 
personal/portable devices, arguing that mobile applications will provide a key driver for economies of 
scale, and that fixed applications promoted by IEEE and others offer little hope for the economies of scale 
needed to produce genuinely affordable equipment.111 The NAF also argues in separate technical 
comments that sensing can provide adequate interference protection to DTV receivers.112 
67. Parties representing TV broadcast and other licensed service interests argue that spectrum 
sensing alone is insufficient to adequately protect licensed services.113 They contend that sensing alone 
would be ineffective for preventing devices from operating within the protected contours of co-channel 
and adjacent channel TV stations and that any sensing capability must be combined with geo-location.114 
MSTV/NAB state that the current sensing proposals are inadequate to protect against co-channel 
interference and that a -116 dBm minimum threshold for sensing licensed signals would not guarantee 
that an unlicensed device would be outside a protected TV stations service area rather than in an area of 
weak signal strength within its service area.115 They further argue that the White Space Coalitions 
recommended detection threshold level of -114 dBm fails to account for important differences in antenna 
height between outdoor TV antennas and TV band devices, disregards real world propagation and 
building attenuation, and ignores the potential interference distance of a TV band device over which 
protection is actually required.116 MSTV/NAB also submitted a report on a signal measurement study in 
the Washington, D.C.-Baltimore, MD area (MSTV Study) that it states found signal levels below the -114 
dBm and -116 dBm levels that have been discussed in this proceeding. The MSTV reports that it 
measured signal levels below -120 dBm.117 In its reply comments, the NAF argues that the measurements 
in the MSTV Study are unreliable due to issues with the way that the measurements were taken and 
systematic methodological errors.118 
68. Motorola, McGraw Hill Broadcasting, and Media General also argue that spectrum 
sensing by itself would not provide adequate protection to users and devices that warrant protection.119 
Motorola is also concerned that the sensing capabilities in devices would need to adapt to detect 
waveforms that may be devised in the future. The Grand Ole Opry and the Microphone Interests 
Coalition, the Professional Audio Manufacturers Alliance, and Shure submit that spectrum sensing is 
promising, but as yet unproven with respect to how it would work in the TV bands to protect incumbents, 
110 See White Space Coalition Further Notice comments at 3. 
111 See NAF, et al. Further Notice comments at 83. 
112 See NAF Further Notice technical comments at 17. 
113 See for example, Grand Ole Opry and Microphone Interests Coalition Further Notice reply comments at 4, IEEE 
802.18 Further Notice comments at 6-7, and MSTV/NAB Further Notice comments at 9-10. 
114 See MSTV and NAB Further Notice reply comments at 11. 
115 See MSTV/NAB Further Notice comments at 11-13. 
116 See MSTV and NAB Further Notice reply comments at 14. 
117 See DTV Signal Measurements in the Washington-Baltimore Area MSTV, attachment to the MSTV/NAB 
comments on Commissions Initial Prototype Devices Report, August 15, 2007 (MSTV Field Study). 
118 See NAF reply comments to the Commissions Initial Prototype Devices Report, September 4, 2007 at 12-17. 
119 See Motorola Further Notice reply comments at 5, McGraw Hill Broadcasting Further Notice comments at 3, 
and Media General Further Notice comments at 2.

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including wireless microphones.120 These parties believe that the Commission should carefully study any 
use of spectrum sensing.121 GE Healthcare is not confident that spectrum sensing technology would 
provide adequate protection to medical telemetry equipment that operates in the TV bands.122 Shure 
initially recommended a detection threshold of -107 dBm for detection of wireless microphones, but in a 
subsequent ex parte submission stated that it now supports the White Space Coalitions lower 
recommended threshold of -114 dBm.123 
69. Several parties submit that spectrum sensing should be used as an adjunct to the geolocation 
method. For example, MSTV/NAB and IEEE 802.18 state that spectrum sensing is needed, but 
is insufficient on its own to adequately and completely protect licensed services. These parties argue that 
the geo-location and database approach are essential to ensure that unlicensed TVBDs operate outside the 
protected contours of both co-channel and adjacent channel TV stations and that sensing could be used to 
detect the presence of wireless microphones, which operate intermittently.124 NCTA states that cable 
headends located outside a TV stations protected contour may receive signals that are undetectable at 
ground level using regular receiver technology. It believes that sensing alone is highly imprecise and will 
not ensure interference protection, so that sensing must be combined with some type of geolocation/
database approach.125 
70. With the exception of the Community Broadcasters Association (CBA), there is very 
little support in the record for adopting a plan that would rely on control signals to provide unlicensed 
devices with a list of channels on which they could operate. The parties that addressed the control signal 
option generally submit that this approach would require the establishment of an expensive infrastructure. 
126 The White Space Coalition and others are further concerned that potential control signal providers 
might not offer service unless they believe that the number of unlicensed devices would make it profitable 
to do so.127 Opponents of the control signal approach also argue that there would be an inherent conflict 
of interest for TV licensees responsible for a database and signaling information that controls access to 
the band.128 CBA supports the control signal approach and offers to have its member stations transmit 
control information.129 
71. Discussion. We find that the geo-location/database and spectrum sensing methods offer 
the most practical solutions for identifying unused TV channels and are therefore incorporating both of 
these methods into the rules for unlicensed TVBDs. Both of these approaches can be implemented using 
relatively cost effective technologies, although we do recognize that the database/system could involve an 
120 See Shure Further Notice reply comments at 5. 
121 See Professional Audio Manufacturers Alliance Further Notice reply comments at 4. 
122 See GE Healthcare Further Notice comments at 6. 
123 See Shure Notice comments at 14 Notice Reply comments at 7. 
124 See IEEE 802.18 Further Notice comments at 6, NAB and MSTV Further Notice reply comments at 11, and 
Shure Further Notice comments at 14-16. 
125 See NCTA Further Notice reply comments at 12-13. 
126 See for example, White Space Coalition Notice comments at 9-10. 
127 Id. 
128 See NAF, et al, Notice comments at 68-69, Tropos Networks Notice comments at 12-13, and White Space 
Coalition Notice comments at 9-10. 
129 See CBA Further Notice comments at 4.

Federal Communications Commission FCC 08-260 
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ongoing cost for users of unlicensed TVBDs. We also find that spectrum sensing, as currently presented 
in our measurement studies of prototype devices, is not sufficient by itself to enable unlicensed devices to 
reliably determine the TV channels that are available for use at a location. However, we believe that 
spectrum sensing offers significant potential for use in detecting the signals of protected services and 
therefore should be included as part of the required means for identifying available channels. 
72. At this time, the geolocation/database approach appears best able to reliably identify 
unoccupied TV channels. Geolocation methods such as GPS can accurately determine the location of an 
unlicensed device and a database system can compare that information to the location and service areas of 
fixed transmitters used by broadcast television and other licensed services. Once the distances between 
an unlicensed device and protected transmitters/service contours are established, adequate and reliable 
protection can be provided by applying standardized protection criteria.130 
73. We recognize the significant and pioneering work of those parties who developed and 
submitted devices for testing as part of our investigation of spectrum sensing in this proceeding. Their 
efforts and that process has contributed greatly to our understanding of the challenges involved in use of 
spectrum sensing to determine occupied channels in the TV bands. From our examination of the 
prototype devices we conclude that while signal detection can and should be used in identifying vacant 
spectrum for use by TVBDs, spectrum sensing with capabilities as presented in the record of this 
proceeding would not, by itself, be sufficient to adequately protect from interference television and other 
licensed services that use the TV bands. In this regard, we observe that sensing the signals of transmitters 
operated in the licensed services that use the TV bands is a challenging task, as reception of those signals 
is often limited by shielding from terrain and structures and by multipath and other fading phenomena. 
This task is especially difficult in the case of personal/portable unlicensed devices, which can be expected 
to be used indoors and at ground level. 
74. As we observed in the First R&O/Further Notice, the facts that personal/portable devices 
have antennas that are less efficient for sensing and may be in a less advantageous position for sensing 
incumbent signals (e.g., a short, non-directional antenna located in an interior room rather than a high 
gain antenna on a 10 meter mast) increases the difficulty of reliably detecting incumbent transmissions. 
With devices operating in such situations, the signal strength that appears at the receive antenna of a 
sensing device can be very weak, and in particular below the -114 dBm and -116 dBm minimum sensing 
levels suggested by the proponents and on which we requested comment in the First R&O/Further 
Notice. 
75. Our conclusions on this issue are based on the following information and analysis for 
digital television service, the principal service that will operate in the TV bands on an ongoing basis. The 
basic principles and results of this analysis are also valid for the signals of wireless microphones and 
other services that use these bands. While we recognize that the DTV, analog TV, and wireless 
microphones each operate at minimum received signal levels, we are not specifying separate minimum 
sensing threshold levels for detection of their signals.131 Rather, we are adopting a single minimum 
required sensing detection threshold value for all TV band services at the minimum sensing level that 
appears to be technically feasible at this time that is adequate to protect authorized services operating in 
the TV band. We note that the commenting parties did not specifically address detection of analog TV 
signals. The rules will, however, require that the sensing feature of unlicensed TV band device detect and 
130 The specific protection criteria for licensed services are discussed in the section below on protection of broadcast 
television and other services. 
131 The service threshold values for signals in the UHF TV band are: DTV signals -84 dBm, analog TV -63 dBm, 
and wireless microphones -87 dBm.

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protect analog TV services because low power analog TV stations will continue to operate after the end of 
the DTV transition. 
76. As discussed above, the threshold signal level for digital TV service in the UHF band is 
-84 dBm/6 MHz at the terminal of a DTV receiver.132 The DTV service model assumes that signals are 
received off-the-air by an antenna with 10 dBd gain that is mounted at 10 meters above ground (about 33 
feet).133 To model an unlicensed personal/portable device, we assume that the device will be used indoors 
on a first floor location and receive signals with an omnidirectional (0 dBi gain) antenna. Several models 
for assessing the difference in TV signal levels between an outdoor TV and an indoor personal/portable 
device were presented in the record. For example, NAB/MSTV submit that signals received by a 
personal/portable device will be 27-32 dB below those received with an outdoor TV antenna (10 dB 
antenna gain + 7 dB antenna height + 10-15 dB for building penetration = 27-32 dB).134 The White Space 
Coalition bases its proposal for a sensing threshold of -114 dBm/6 MHz on the assumption of up to 30 dB 
difference between the location of a TV antenna and an unlicensed device.135 The NAF appears to 
indicate, based on an engineering assessment submitted with its technical comments, that this difference 
is 26-31 dB.136 Motorola submits that the received signal level at an indoor white space device would be 
18-39.5 dB lower than that received by an outdoor TV antenna (10-16.5 dB antenna height + 3 dB 
polarization mismatch + 5-20 dB or more building penetration = 18-39.5 dB).137 As reflected in these 
different models and empirical studies, there will plainly be significant variation in the signal attenuation 
from rooftop to indoor locations across different sites (and even at different locations indoors at the same 
residential site). To simplify our analysis here, we will begin by assuming a moderate level of attenuation 
as represented by these models, or 30 dB (we do recognize that in many cases this difference can be 
significantly higher). Thus, the -84 dBm DTV minimum service threshold less the 30 dB difference 
between an outdoor TV antenna and an indoor white space device antenna yields a signal level that 
corresponds to the -114 dBm/6 MHz minimum sensing threshold suggested by some parties in the record. 
77. If a TV stations signal were always at or above 41 dBV/m (-84 dBm) within its service 
area and the difference in received signal level between an outdoor antenna and an indoor white space 
device antenna were always 30 dB or less, it could be anticipated that a white space device with a 
132 Most DTV stations operate on UHF frequencies. Other analytical values are appropriate for use in evaluating a 
minimum sensing threshold for the high VHF and low VHF bands (see below), but our conclusion on the issue of 
whether sensing should be permitted to be used as the only means of determining the availability of channels for use 
by white space devices can be adequately explained by only examining signals in the UHF band. 
133 See Sixth Report and Order in MM Docket No. 87-268, 12 FCC Rcd 14558 (1997) at  183-195 and Appendix 
B; see also OET Bulletin No. 69, Longley-Rice Methodology for Evaluating TV Coverage and Interference, FCC 
Office of Engineering and Technology, February 6, 2004 at Table 4 (OET-69 is available at 
http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet69/oet69.pdf. Using this receive 
system model, the -84 dBm signal strength (in milliwatts) needed for UHF service at the receiver terminal means 
that the minimum field strength (in microvolts) needed to receive a signal is 41 dBu. The formula for this model 
and the conversion of received field strength into signal strength is provided in OET-69, page 4. 
134 See MSTV Further Notice comments at footnote 29 and written ex parte submission, May 21, 2007. 
135 See White Space Coalition Further Notice comments at 6 
136 See NAF Further Notice technical comments at 17. The NAF specifically states that it believes a sensitivity 
level in the range of -110 to -115 dBm should be adequate to protect TV receivers given mobile powers of 
100 mW. We subtracted -84 dBm from these figures to obtain the values indicated above, but recognize that the 
NAF may have considered other factors in their suggestion for a minimum sensing threshold. 
137 See Motorola written ex parte presentation of October 18, 2007 at 17-20.

Federal Communications Commission FCC 08-260 
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minimum sensing level of -114 dBm would be able to reliably detect the presence of a TV stations signal 
within the stations service area. However, in practice there will be cases where 1) a stations signal is 
below 41 dBu within its service area, and 2) the difference in received signal level between an outdoor 
and indoor antenna at the same structure/location will exceed 30 dB. In either case, if the deficiency in 
signal level is not offset by an equal or greater signal level in the other component, then the signal level of 
the TV station received at the white space device will be below -114 dBm. For example, a signal as 
received at an outdoor antenna is 35 dBmV/m (6 dB less than the service threshold), then the signal could 
still be detected at -114 dBm if the signal attenuation between the outdoor and indoor receive antenna 
positions were 24 dB rather than 30 dB. 
78. With regard to the variability of signal levels across different sites, it is well established 
that there are locations within DTV stations F(50,90) noise-limited service contours where their signals 
are below the level needed for service such that service is not available. Such locations are likely to occur 
in more distant portions of TV station service areas and certain other locations within a stations service 
area where, due to shielding by terrain or structures (hidden nodes), the stations signal will not be 
strong enough to be received under the standard TV service model. The definition of the service area of a 
DTV station in Section 73.622(e) of the rules specifically recognizes that a TV stations signal will not be 
available everywhere within its service area. That definition provides that [t]he service area of a DTV 
station is the geographic area within the stations F(50,90) contour where its signal strength is predicted to 
exceed the noise-limited service level.138 Congress also recognized that TV signal levels will be below 
the service threshold at individual locations in the Satellite Home Viewer Extension and Reauthorization 
Act of 2004 (SHVERA).139 Section 204 of the SHVERA directed the Commission to conduct an inquiry 
on whether the Commission should revise its digital TV signal strength standards and signal measurement 
procedures used to identify if a household is unserved for purposes of the satellite copyright license for 
distant signals.140 In response to this statutory charge, the Commission issued a Notice of Proposed 
Rulemaking proposing to amend its rules to include procedures for measuring the field strength of digital 
television signals at individual locations.141 The variability of TV signal strengths across different nearby 
locations recognized in these established regulatory and statutory provisions is also apparent from the 
field studies in the record of this proceeding.142 
79. Further, as demonstrated by the various field measurement studies in the record of this 
proceeding, the signals of TV stations in particular vary substantially over short distances within the 
138 47 C.F.R.  73.682(e). Section 73.622(e) further provides that [w]ithin this contour, service is considered 
available at locations where the stations signal strength, as predicted by the Longley-Rice propagation model, 
exceeds [the noise-limited service levels. 
139 The Satellite Home Viewer Extension and Reauthorization Act of 2004, Pub. L. No. 108-447,  204, 118 Stat 
2809, 3393 3423-24, (2004), codified at 47 U.S.C. 339(c)(1). The SHVERA was enacted as title IX of the 
Consolidated Appropriations Act, 2005. 
140 On December 9, 2005, as required by Section 204(b) of the SHVERA, the Commission issued a Report to 
Congress, Study of Digital Television Field Strength Standards and Testing Procedures (SHVERA Report), ET 
Docket No. 05-182, 20 FCC Rcd. 19504 (rel. Dec. 9, 2005). 
141 See Notice of Proposed Rulemaking in ET Docket No. 06-94, 21 FCC Rcd 4735 (2006) at  5. Therein, the 
Commission indicated that while these measurement procedures would be generally applicable for measuring digital 
TV signal strengths, they would specifically be used in determining if a household is served by a digital television 
signal as part of an evaluation of the households eligibility to receive a distant digital network signal from a satellite 
television provider. 
142 See The White Space Coalitions written ex parte presentation Microsoft/Philips Field Tests Report of 
September 20, 2007; see also MSTV Field Study.

Federal Communications Commission FCC 08-260 
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station service areas. These studies provide empirical indication that there is considerable variability in 
the difference in signal levels received with an outdoor antenna at about 9 meters and with an indoor 
antenna at differing positions within a structure. For example, the MSTV Study (notwithstanding the 
concerns expressed with respect to certain aspects of its methodology), a study of DTV signals at 
residences submitted by the NAF, and White Space Coalitions Microsoft/Philips Field Tests report 
consistently show that there is substantial variation in the DTV signal levels outdoors and indoors at a 
residence that are consistent with the models discussed above.143 These studies also show variation 
within residences of as much as 20 dB and in a few cases more. If we take the middle of this range of 
variation to be the signal level as that which would be determined using the 30 dB difference between an 
indoor and an outdoor antenna, then some locations would receive signals 10 dB higher and some would 
see signals 10 dB lower.144 At those positions within a structure where the signal level is below the 
middle level (up to 10 dB lower, taking half the 20 dB range), the signal level in our model would be 
lower than -114 dBm and as low as -124 dBm or less. At any of these levels, the signal would plainly not 
be detectable by a device that can only sense down to -114 dBm; a device that could sense as low as the 
-116 dBm level we suggested in the First R&O/Further Notice would also not be adequate to reliably 
detect TV signals. As discussed below, it is also possible that the stations signal at a nearby location 
would be strong enough to provide service, in which case interference could occur if an unlicensed device 
were to transmit. 
80. The White Space Coalition contends that interference protection should not be afforded at 
locations where a TV signal is too weak to be received.145 It argues that the touchstone of a claim of 
interference is whether that interference negatively impacts a signal that would otherwise produce a 
viewable picture. We generally agree that interference protection should not be afforded where service is 
unavailable and our rule defining DTV service areas does not include areas within a stations noiselimited 
contour where its signal is predicted to be below the threshold of service.146 However, we also 
recognize that the signals of a low power unlicensed device operating at a location within a TV stations 
noise-limited contour where the stations service is not available also could reach areas where service is in 
fact available and thereby cause interference. The information above establishes that the distances 
between locations where service can be received and those where service cannot be received can be short. 
We therefore conclude that a device operating within a TV stations noise-limited contour at a location 
143 With respect to its indoor measurements, the MSTV Study showed significant variations in the field strength of 
local TV stations in different rooms and outdoors at ground level at residential locations within the stations service 
areas, while at the same time reception was generally available on the homes DTV receiving system. See also 
Attachment to NAF Technical comments, White Spaces Engineering Study: Can Cognitive Radio Technology 
Operating in the TV White Spaces Completely Protect Licensed TV Broadcasting? Working Paper #16, (NAF 
Study) Mark Sturza and Farzad Ghazvinian, January 2007. The NAF conducted field tests at three residences 
located 25-26 miles from local DTV station transmitters (these sites would be expected to be moderate field strength 
locations) and found variations in DTV field strengths within individual residences of 39.1 dB, 35.3 dB, and 
22.4 dB. The White Space Coalitions Microsoft/Philips Field Tests Report of September 20, 2007 indicated a 
number of instances in which DTV signal strengths varied by more than 20 dB at different locations within a 
building/residence and one site where the DTV signal variation within a room was more than 30 dB. See 
Microsoft/Philips Field Tests, presented to OET September 20, 2007 (PowerPoint presentation). 
144 We understand that an argument could be made for using the highest level of the 20 dB range in indoor 
measurements as the signal level that would be determined using the 30 dB difference between an indoor and an 
outdoor antenna. However, use of the middle of this range provides a conservative analysis and does not change the 
basic conclusion of our analysis in any case. 
145 White Space Coalition Further Notice reply comments at 9-10. 
146 47 C.F.R.  73.622(e).

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34 
where the stations service is not available could nonetheless cause interference at locations where the 
stations service is available. 
81. The variability of propagation over short distances also makes it impractical to evaluate 
the likelihood that a device located at any given location would cause interference. There will also be 
cases where, due to the approximate nature of predictive models, service will be available and received at 
locations within a stations noise-limited contour where service is not predicted to be available. We find 
that service to these viewers should be protected the same as viewers in locations where service is 
predicted to be available. Therefore, to ensure that TV service is properly protected, we will assume that 
a device operating on the same channel as a TV station could cause interference if it were located 
anywhere within a stations noise-limited contour. 
82. In considering the role of spectrum sensing in detecting licensed signals in the TV bands, 
we are aware that sensing technology for consumer products, including the minimum threshold level 
needed to detect licensed signals in these bands and algorithms for reliably detecting DTV, analog TV, 
and wireless microphone signals at any sensing level, is still in its nascent stage. The performance of the 
white space development devices that we tested showed significant potential but also demonstrated the 
need for additional work on solutions for handling the significant dynamic range of signal field strengths 
that characterize the service in the TV bands. The devices examined in our Laboratorys measurement 
program were not able to sense with a high degree of accuracy both TV and wireless microphone 
performance in different real world environments where signals are subject to different levels and forms 
of fading, multipath, and other degradations. In particular, our measurement studies found that while the 
prototype devices were generally able to detect clean TV and wireless microphone signals on a channel 
with no other signals present, their ability to reliably detect unoccupied channels degraded to levels we 
consider unsatisfactory when the test signals included multipath and other fading effects and when signals 
were present on other channels. The performance of the devices was observed to degrade substantially 
and at increasing levels as the level of the signals on adjacent channels was raised. Both fading and 
relatively stronger signals on adjacent channels are a normal part of the signal conditions in the 
environment of the TV bands and any device that uses spectrum sensing to determine whether a channel 
is occupied will have to be able to perform reliably when such conditions are present. 
83. We also find unconstructive sensing performance that incorrectly determines all or nearly 
all unoccupied channels to be occupied, that is the device finds all occupied channels and all or nearly 
unoccupied channels to be occupied. While a device that returns such results could be seen as minimizing 
the potential for interference to authorized services, it would not be practically viable because it would 
allow its transmitter to operate on very few channels or perhaps none. 
84. In view of these results, we believe that much more developmental work needs to be 
accomplished before the spectrum sensing technique can be implemented as the principal means of 
identifying unoccupied channels in the TV bands, even in the case of fixed unlicensed devices that use 
outdoor antennas. Thus, we are not convinced that spectrum sensing as currently presented could 
adequately serve as the only means to protect TV services and other fixed protected contour services from 
interference by unlicensed TVBDs operating at the power levels proposed in the Notice. Coupled with 
this concern, we also observe that the significant distances at which interference could occur from an 
unlicensed TVBD operating at greater than 100 mW would make it very difficult to identify the TVBD as 
the source of the interference.147 
147 Using the TM90 propagation model (this model is for short distances and low antennas), for the situation in 
which an indoor unlicensed TV band device would impact an outdoor DTV antenna at 30 feet, our staff calculates 
that a 100 mW signal could cause interference at a distance of 1400 meters in locations where the DTV co-channel 
D/U ratio is 23 dB and at a distance of 900 meters in locations where the DTV co-channel D/U ratio is 15 dB. See 
(continued.)

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35 
85. In view of these concerns, we will rely principally on the geo-location/database method 
to protect incumbent fixed services from interference from TVBDs. The service areas of fixed transmitter 
TV and low power TV stations, PLMRS/CMRS operations, production locations that use wireless 
microphones, and other operations with defined operating areas do not change often and their channel 
numbers, transmitter geographic coordinates, and other operating parameters can be stored in a database. 
The protected service contours of these fixed transmitter services are clearly defined and can be 
calculated from information in the database. Therefore, it is a relatively straightforward for an unlicensed 
TVBD with geo-location capability to access a database system which would determine whether the 
TVBD is sufficiently far outside the protected service areas of licensed TV band services to ensure that it 
will not cause interference to those services. Accordingly, we will require that all TV band devices use a 
geo-location and database approach to determine unused TV channels in their area on which to operate or 
to operate as a client to a device that has obtained a list of the unused channels using that method. 
86. As the location of a fixed device does not change, it is only necessary to determine the 
devices location once, at the time of installation and first activation, after which the devices coordinates 
can be stored internally. We will therefore allow the geo-location function for fixed devices to be 
performed by either an incorporated geo-location capability or a professional installer. In the case that the 
stored coordinates in a fixed device become corrupted, it will be necessary for the operator to re-activate 
the devices internal geo-location function or for a professional installer to re-enter those coordinates in the 
device. Personal/portable devices operating on an independent basis (which will require use of a geolocation 
capability) will be required to re-establish their position each time they are activated and to reverify 
their position with the database on a regular basis. Personal/ portable devices operating on a client 
basis (which will not require use of an internal geo-location capability) will also be required to receive the 
list of available channels in their area from a fixed device or personal/portable device operating in Mode 
II that has determined the available channels in the area through the geo-location and database method 
and controls the frequencies on which the personal/portable device operates. 
87. We also recognize that a personal/portable device operating independently and on battery 
power could be relocated from its activation point to a different location where the available channels are 
different without being deactivated in the period before it re-verifies its location with the database. In such 
cases, the device could operate on a channel in use by a licensed service and cause interference. We will 
therefore require that personal/portable devices operating in Mode II access the database each time their 
geolocation feature detects that the device has been moved. In addition, to ensure that personal/portable 
devices operating in Mode II are always under control of geolocation, we will require that they cease 
transmitting at anytime they are not able to determine their location. 
88. We recognize that requiring access of and, in the case of fixed devices, registration with a 
database will increase the costs of unlicensed TV band devices, both from the increased complexity of the 
devices and the potential for the database administrator to charge fees necessary to support its operations and 
will also reduce the manufacturers flexibility in designing these devices. However, we believe that given the 
available alternatives, requiring use of geo-location and a database for fixed TV band devices is necessary to 
ensure protection of the licensed television and other services that operate in the TV bands. We will also 
permit parties to petition us to review any fees that appear to be excessive. 
89. As discussed below in the Database Requirements section, we will require that the database 
administrator include in the database records on the fixed incumbent licensed users of the television band, 
(Continued from previous page) 
Propagation in Suburban Areas at Distances less than Ten Miles, William Daniel and Harry Wong, January 25, 
1991. We also note that the anecdotal transmitter tests at out Laboratory showed co-channel interference at 
360 meters (1180 feet), which was the maximum possible separation that could be achieved at the Laboratory.

Federal Communications Commission FCC 08-260 
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including full service and low power television stations, PLMRS/CMRS, BAS links, and Offshore 
Radiotelephone Service stations. We also understand that there are many facilities that use low power 
auxiliary devices such as wireless microphones on a regular basis. In addition, cable headends and low 
power TV receive sites located outside of TV station protected service contours often use high gain 
antennas mounted on towers and/or at high elevation to receive TV signals and then distribute them to 
large numbers of subscribers and viewers. We believe that it would be appropriate to extend the 
protection afforded by the database system to cable headends and will therefore provide for registration of 
such facilities in the database. In addition, we will allow the operators of event and production facilities 
where low power auxiliary devices such as wireless microphones are regularly used to register those sites 
in the database. 
90. Fixed and Mode II personal portable unlicensed TV band devices will access the database 
over the Internet and provide it with their location. The database system will then calculate which 
television channels are available for use by TV band devices at their location based on the information in 
the database and return a list of those channels to the TV band device. The database will register 
unlicensed fixed devices and record appropriate information, including the devices location and user 
contact information. Personal/portable devices operating on either a client or independent basis will not 
need to be registered in the database. The registration information for fixed stations will be available to 
entities recognized by the Commission to assist TV band device users in coordinating efficient use of the 
available television channels at a particular location. In addition, the registration information could be 
used to assist the Commission or its designated agents in the identification of the source of any 
interference to licensed services from TV band devices. We are not specifically requiring professional 
installation of fixed unlicensed TVBDs or the use of GPS or any particular location technology in a fixed 
station. Our concern is with the accuracy and reliability of the location information, rather than the 
method used to obtain the information, and we believe that the requirement that a device not operate until 
and unless the geo-location/database process has been completed will be sufficient to ensure that devices 
are provided a reliable list of the channels used by TV and other licensed fixed transmitters in their area. 
91. In order to ensure that fixed unlicensed TV band devices with radio-based geolocation 
capabilities are able to receive GPS or other location signals, we are requiring that the receive antenna for 
the geo-location function be located outdoors and at the same location as its subject TVBD transmitter. 
Personal/portable devices operating in Mode II with radio-based geolocation capabilities in most cases 
will also need to be located outdoors to receive geolocation signals; we will allow these devices to receive 
such signals through a separate antenna that is located outdoors.148 We also find that the 10 meter 
accuracy we proposed to specify for the geo-location capability, while well within the capabilities of the 
GPS system, would be more accurate than is needed for purposes of identifying the locations of 
unlicensed TVBDs. We are also concerned that requiring accuracy to 10 meters might preclude the use of 
other options for geo-location that are less accurate than GPS but would still provide an adequate degree 
of accuracy. We believe that 50 meters is a reasonable degree of accuracy for the geo-location capability 
used to determine the coordinates of unlicensed TV band devices. The effectiveness of the separation 
distances we are providing for TV and other services are adequate to provide protection in an 
environment where location errors of up to 50 meters may occur. Also, an accuracy of 50 meters is 
readily achievable using commonly available methods such as GPS and will also provide flexibility for 
use of alternative geo-location methods. In the case of professional installation, the party who registers 
the fixed station in the database will be responsible for assuring the accuracy of the entered coordinates. 
148 If the separate antenna became detached such that the Mode II personal/portable device is no longer able to 
determine its location it will be required to cease transmitting.

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92. We will require that unlicensed TVBDs incorporate spectrum sensing capabilities to 
complement their geolocation/database access capabilities in determining channel availability. TVBDs 
that sense wireless microphone operations on a TV channel will not be allowed to transmit on that 
channel. We will also require that devices that detect a TV signal on a channel must cross-check with the 
channel availability report from the database to verify that the device is within the service area of a TV 
station on that channel at the devices location. If the channel is reported by the database as available at 
that location, i.e., the device is not within the service areas of any TV stations that use that channel, then 
the device will be required to notify the user that the channel appears to be occupied. 
93. We also recognize the position of IEEE 802.18, Shure, and others that the geolocation/
database method is not suitable for identifying channel occupancy by devices such as wireless 
microphones that operate on an intermittent, occasional, or one-time basis at locations not identified in the 
database. Wireless microphones are licensed on an area basis, rather than specific geographic 
coordinates. A wireless microphone user may operate anywhere in that area and choose a frequency from 
multiple vacant channels available for operation. It is not practical to require that the locations of wireless 
microphones that are used in this manner be included in the database. There may also be TV stations and 
other regularly operating TV band licensed stations on the air in an area that for some reason are not in 
the database. We agree with Shure and others that spectrum sensing is the most reasonable and 
appropriate approach for detecting the presence of TV band services that operate on an intermittent basis 
or are not in the database. The prototype devices developed by the White Space Coalition, Motorola, 
Google and others indicate that work is under way to improve the performance of this technology in 
sensing wireless microphones and we believe that, at this time, it is satisfactory as a complement to the 
database system and for providing a capability for the detection of unregistered wireless microphone 
operations. Accordingly, we will require that all unlicensed TV band devices incorporate a spectrum 
sensing capability to detect wireless microphones and to use that capability in determining the available 
channels in their area. 
94. Television signals and wireless microphone signals use different amounts of bandwidth 
and modulation methods and TVBDs can thus differentiate between them.149 In cases where a TVBD 
detects a wireless microphone operation on a TV channel, the device will not be allowed to operate on 
that channel. In cases where a TVBD detects the signal of a digital or analog TV station, we recognize 
that it is possible that the signal is being detected outside of the stations service area. In such cases we 
will not protect the TV service; rather, we will only require TVBDs to protect TV signals within a 
stations service areas, except relative to cable head-ends and translator sites as indicated below. Thus, if 
a device detects a TV signal we will require the device to avoid operation on that channel only if the 
database also provides information that the device is within the protected range of a TV station. Where a 
TVBD detects a TV signal outside of the protected range of any TV station, we will require that the 
device notify the user and provide a capability for the user to manually, at his or her discretion, set the 
device to avoid operating on that channel. This feature will allow users to avoid operating their TVBDs 
on channels where out-of-service area TV signals are being received locally. Thus, the geolocation/
database process will control the list of available channels at a location within a TV stations 
service area and device users will have the option of avoiding additional channels detected outside of any 
stations service area. 
149 A TV signal occupies essentially all of a 6 MHz TV channel whereas a wireless microphone occupies only a 
200 kHz segment of a TV channel (multiple wireless microphones can use a single TV channel). In addition, 
wireless microphones use different analog and digital modulation methods than the analog and digital modulation 
methods used for television transmissions.

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95. Based on the submissions of Shure and IEEE.802.18 on the minimum sensing thresholds 
needed, our testing of the prototype devices, and the practical limits of sensing indicated in ex parte 
discussions with representatives of the White Space Coalition and other prototype developers, we 
conclude that sensing at a -114 dBm minimum detection threshold is appropriate and feasible to protect 
wireless microphones and the signals of other services that operate in the TV bands on an intermittent 
basis and for detecting TV stations that do not appear in the database for whatever reason.150 This 
minimum sensing threshold will provide the maximum likelihood of detecting the signals of licensed 
services, and particularly wireless microphones, in the area of an unlicensed TVBD that is consistent with 
manufacturing economics. In this regard, we believe that it is best to require use of the most sensitive 
level of detection capability that is economically feasible for sensing the signals of all services. Given 
that wireless microphones operate in relatively narrow bandwidths and that both wireless microphones 
and analog TV signals have distinctive signal characteristics, we also believe that the -114 dBm level we 
are adopting will provide the same or better protection in detecting wireless microphones and analog TV 
signals as digital television signals. Additional discussion of our decision on the minimum spectrum 
sensing threshold is provided in the section below on technical requirements. 
96. We also anticipate that use of sensing under both the client and independent mode 
approaches for personal/portable devices will allow manufacturers to gain experience with sensing that 
could be used to develop improvements in such capabilities that could then perhaps justify greater 
reliance on spectrum sensing for determining whether TV channels are occupied. Personal/portable 
devices operating in the client mode will also be required to pass information on any signals that they 
sense back to the master device and the master device will then take appropriate steps with respect to its 
list of available channels to avoid the channel sensed by client devices. That is, if the client device senses 
a wireless microphone on an otherwise available channel the master device will be required to remove 
that channel from its list of available channels. If the client device senses a TV station on a channel 
outside the service areas of any TV stations, the master will be required to notify the operator and provide 
the option to remove that channel from the devices list of available channels. In the sections below, we 
present the specific provisions of our rules for operating under the above plans for determining whether 
TV channels are occupied or unoccupied, including the minimum required distances that devices using 
the geo-location/database method must be from the protected contours of licensed services and the 
requirements for spectrum sensing of wireless microphones. 
97. While we continue to believe that the control signal approach has merit as a means to 
communicate available channels to unlicensed TVBDs, we also recognize the practical constraints that 
lead the commenting parties to oppose this approach and will not include a control signal element in the 
rules we are adopting.151 We would, however, revisit this option if the economics or other circumstances 
develop in a manner that would favor the viable operation of a control signal system. 
150 See Shure Notice comments at 14 and IEEE 802.18 Further Notice comments at 9. We also note that the White 
Space Coalition recommended a minimum sensing threshold level of -114 dBm in their comments responding to the 
Further Notice, at 7. While a sensing threshold of -114 dBm may not identify a TV station not in the database at 
every location within the stations service area, the stations signal will be above that level at enough locations that 
its presence will be identified and reported to the database administrator so that the database can be corrected. We 
note that a -114 dBm detection threshold in 6 MHz is equivalent to -132 dBm in a 100 kHz bandwidth. 
151 Although we appreciate the CBAs offer that its member stations could serve as control signal transmitters, its 
member stations could not provide the near ubiquitous coverage that would be needed to support a viable control 
signal system for unlicensed TVBD devices. 

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98. We also do not believe it is necessary to require that unlicensed devices recognize and 
respond to beacon signals that would carry information on channels to avoid at events using wireless 
microphones, as requested by Shure and others representing wireless microphone interests. We believe 
that other actions we are taking in this matter, including restricting unlicensed personal/portable devices 
from operation on channels 2-20 and adjacent channels used by TV and providing for registration of sites 
that use wireless microphones in the database, will ensure that wireless microphones are able to operate 
without receiving interference from unlicensed TV band devices. We are concerned that such beacon 
signals would occupy spectrum that could better be used for radio service operations themselves and 
would impose an additional and unnecessary cost on licensees. 
2. Fixed Devices 
99. In the Notice, the Commission anticipated that fixed unlicensed TVBDs would, in 
general, be used by WISPs and others as base stations to provide Internet access and other broadband data 
services to homes and businesses, including service to both fixed and personal/portable services. It 
therefore proposed to allow fixed TVBDs to operate under the same technical provisions as digital 
transmission systems that operate under Section 15.247 of the rules.152 Under those provisions, fixed 
unlicensed TV band devices would be permitted to operate with transmitter output power up to 1 watt and 
to employ higher gain directional antennas, with requirements for transmitter output reductions for 
antennas with gains above 6 dBi. This would allow fixed devices to operate with the equivalent to an 
EIRP of 4 watts. The Commission further proposed to require that such devices automatically and 
periodically transmit a unique identification so that any harmful interference situation, should one occur, 
could be quickly identified and remedied. It also sought comment on whether these devices should be 
subject to routine evaluation for RF exposure.153 The Commission requested comment on whether 
additional requirements would be appropriate for fixed unlicensed TVBD operations. In particular, it 
asked whether it should require that all fixed devices be registered with an industry-accepted entity, such 
as a frequency coordinator, that maintains a registration database of all fixed transmitters along with their 
operating frequencies. 
100. As indicated above, in the First Report and Order the Commission decided to allow fixed 
low power devices to operate in the TV bands, subject to final technical rules to be adopted in this 
subsequent action to ensure that they do not cause interference to authorized services within the TV 
bands.154 It gave several reasons for reaching this decision. First, there will be significant unused 
spectrum available in many parts of the country after the DTV transition, either because of the minimum 
separations required between authorized stations to avoid interference or because available TV channels 
have not been assigned (due to lack of demand) and other services are not using those vacant channels. 
The Commission also found it reasonable to expect that existing technology can be adapted to allow 
devices to identify unused spectrum in a given geographic area, and noted that the IEEE 802.22 Working 
Group was in the process of developing a standard to enable fixed devices to successfully share spectrum 
with authorized services in the TV bands. 
101. With respect to transmit power, Shure believes that fixed devices should be limited to 1 
watt conducted power and 4 watts EIRP.155 IEEE 802 supports the proposed power limits and states that 
152 See Notice at  25; see also 47 C.F.R.  15.247(b)(3). 
153 See 47 C.F.R.  1.1307(b) and 2.1091. 
154 See First Report and Order at  17. 
155 See Shure Notice reply comments at 20.

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it may be possible to increase them in the future.156 CWLab believes that a fixed system using an antenna 
with a beamwidth of less than 120 degrees should be allowed an EIRP of 25 watts, while Shared 
Spectrum Company believes that fixed network systems should be permitted peak power levels of 10 
watts.157 The Society of Broadcast Engineers, on the other hand, argues that 4 watt EIRP devices are not 
low power products and that they would not be suitable for unlicensed Part 15 operation because they 
would inevitably cause interference to broadcast TV and other stations operating in the TV bands. It 
believes that the proposed power limit should be reduced by a factor of 100 (20 dB) for TV band devices 
to be rightfully characterized as Part 15 products.158 A number of parties express support for the IEEE 
802.22 model for fixed operation. 
102. MSTV/NAB believe that the Commission should develop rules for fixed operation based 
on IEEE 802.22s draft plan for fixed access, including its prohibition on co-channel and first adjacent 
channel operation and use of a combination of geo-location and spectrum sensing to determine channel 
availability. In that plan, spectrum sensing would be employed as an added rather than sole protection. 
MSTV/NAB state that this approach would enable a broadband plan without endangering television 
reception.159 Cox Broadcasting, ION Media Networks, McGraw-Hill Broadcasting and Media General 
also believe that if the Commission allows fixed operation, then it should follow the IEEE 802.22s 
recommendations.160 
103. Microsoft believes these devices should be exempt from routine evaluation for 
radiofrequency (RF) exposure. It states that the proper RF exposure context for unlicensed TV band fixed 
devices is a device with 1 W transmit power and a 5./8 vertical antenna in an occupational/controlled 
environment and mounted on a tower or roof. Microsoft states that to reach the maximum permissible 
exposure (MPE) limit, an individual would have to remain within one inch (six inches for a high power 
device) of the antenna of a device operating at maximum transmit power and at 100% duty cycle for a 
period of 6 minutes. It states that this is not likely to happen in the real world. 
104. Discussion. We are adopting rules for fixed TV band devices that are based on a system 
architecture model that is generally similar to the model being developed in the IEEE 802.22 Working 
Group. Under the plan we are adopting, unlicensed TVBDs will be allowed to provide wireless 
broadband services, e.g., wireless Internet access, and other services using multiple vacant TV channels 
and will be permitted to operate on a fixed, point-to-point or point-to-multipoint basis. A fixed system 
will consist of a permanently located base station transmitting to one or more fixed devices or to 
personal/portable end user devices. 
105. As proposed, we will generally limit fixed unlicensed TV band devices to a peak 
transmitter output power of one watt with a maximum antenna gain of 6 dBi and require that transmitter 
power be reduced by the same amount in dB that the maximum antenna gain exceeds 6 dBi. This will 
allow fixed unlicensed TVBDs to operate with the equivalent of 4 watts EIRP. If the maximum antenna 
gain exceeds 6 dBi, the transmitter power will be required to be reduced by the amount in dB that the 
antenna gain exceeds 6 dBi so that the EIRP does not exceed 4 watts. Transmitter power will be 
156 See IEEE 802.18 Notice comments at 6. 
157 See CWLab Notice comments at 3 and Shared Spectrum Company Notice reply comments at 5. 
158 See Society of Broadcast Engineers Notice comments at 1. 
159 See MSTV/NAB Further Notice comments at 33. 
160 See Cox Broadcasting Further Notice comments at 4, ION Media Networks Further Notice comments at 3, 
McGraw-Hill Broadcasting Further Notice comments at 3, and Media General Further Notice comments at 2.

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measured at the antenna input to account for any cable losses between the transmitter and the antenna. 
We continue to believe that 4 watts EIRP is sufficient to allow fixed devices to communicate at ranges 
that will serve community and rural users while minimizing the potential for interference to broadcast 
television and other authorized services in the TV bands. These power/antenna limits are the same as 
those permitted for spread spectrum transmitters operating in the 915 MHz band under Section 15.247 of 
the rules and have proven sufficient for WISPs to provide broadband services in that higher frequency 
band. Because the TV band frequencies are below 915 MHz and have better propagation characteristics 
than higher frequencies, operation at the power levels we are adopting will allow improved coverage for 
wireless broadband service providers. 
106. We also recognize that there are advantages, such as reduced infrastructure costs and 
increased service range, to operation of unlicensed TVBDs at even higher power levels. We will not, 
however, generally allow operation of these devices at power levels greater than 4 watts EIRP for two 
reasons. First, operation at higher power levels would increase the risk of interference in congested areas 
and thus could make sharing spectrum between TV band device users more difficult. This concern 
extends to higher EIRP levels using high gain antennas with narrow beamwidths, as such effective power 
levels would pose greater interference potential in the direction of the antennas main beam. Second, 
inasmuch as we do not have experience with unlicensed wireless broadband operations in the TV bands, 
we find it prudent to take a more cautious approach in setting power limits to minimize the risk of 
interference to authorized users of the TV bands. Nevertheless, the Commission will further explore in a 
separate Notice of Inquiry whether higher powered unlicensed operation might be accommodated in the 
TV white spaces in rural areas. 
107. With respect to SBEs concern that 4 watts EIRP is too high for an unlicensed device and 
could possibly result in interference to broadcast and auxiliary stations, we believe that other aspects of 
the plan we are adopting adequately address this concern. In particular and as discussed below, we are 
requiring TV band devices to incorporate specific interference avoidance features to prevent interference 
to authorized users in the TV bands and the technical parameters for those features were developed based 
on the 4 watt EIRP power level. We also believe that the requirement for fixed devices to operate at 
outdoor locations will provide sufficient separation from consumer TV receivers to avoid direct pick-up 
interference from their operations to cable service. 
108. In order to ensure that unlicensed TV band fixed devices can be identified if interference 
occurs, we are requiring that all such devices transmit identifying information and be registered with the 
database system. The identification signal will be required to conform to a standard established by a 
recognized industry standards setting organization. We will expect the identification signal to carry 
sufficient information to identify the device and its location. 
109. Devices must be designed so that they will not transmit (beyond the brief messaging 
necessary to complete the registration process in the case of a device connecting to the internet through 
another fixed device) unless they are currently registered and have received an authorizing response from 
the database system. To register a fixed device, the party responsible for the device will be required to 
provide the database system the devices FCC identifier (FCC ID) and serial number, the geographic 
coordinates of the devices location (from the geo-location capability), the responsible partys name, the 
name of a contact person, and the contacts address, e-mail address and telephone number. The required 
registration can be accomplished the first time the device accesses the database to determine the available 
channels in its area. While registration in the database system will pose some additional burden, we 
observe that manufacturers of internet access equipment and computing software now typically request 
that users register their equipment or software purchase with its manufacturer/producer. Thus, systems 
with registration capability are already widely in use and both manufacturers and users are familiar with 
registration procedures. The process to be implemented by the database operator for registering 
unlicensed TV band fixed base stations is expected to be similar to these existing registration procedures. 

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We therefore do not believe that it will be unduly burdensome to develop or comply with this registration 
procedure. 
110. We note that the IEEE 802.22 draft standard does not provide for fixed devices to 
communicate with personal/portable devices. However, under the rules we are adopting, fixed TVBDs 
will be allowed to communicate with personal/portable devices operating independently or using a 
master/client model. We believe that allowing communications between fixed and personal/portable 
devices will significantly enhance the service benefits of both types of TV white space devices. In this 
regard, a fixed base will be able to provide direct internet access and other services that may be developed 
to a large number of personal/portable devices within its service range. 
111. For purposes of these devices, we are defining the terms master and client as we have 
for other types of Part 15 devices.161 That is, a master device is one that operates in a mode in which it 
has the capability to transmit without receiving an enabling signal, to select a channel, and to initiate a 
network by sending enabling signals to other devices. A client device is one whose transmissions are 
under the control of the master and is not able to initiate a network. A network always has at least one 
device operating in master mode and also some devices that may be capable of operating only in client 
mode and some devices that may be capable of operating in either mode. All fixed TVBDs will be 
allowed to operate in master mode. Those personal/portable devices communicating on a master/client 
basis with a fixed device will be required to use channels/frequencies as directed by the fixed device. 
Thus, a personal/portable device operating under this arrangement will pose no more risk of interference 
to a licensed service than the fixed device, and because it will use less power will generally pose less risk 
of causing such interference. We note that, because the fixed master device will not transmit if its service 
area would cause harmful interference to a licensed user in the database, the client devices would by 
definition be within that service area and would likewise not cause harmful interference. 
112. If a fixed unlicensed TV band device that does not have a direct connection to the internet 
(that is a connection provided by a source other than another TV band fixed device) has not yet been 
initialized and registered with the database system and can receive the transmissions of another fixed TV 
band device, we will allow the device needing initialization to transmit on either a channel that the other 
TV band device has transmitted on or on a channel which the other TV band device indicates is available 
for use.162 The TV band device needing initialization must then immediately use its communications link 
with the other TV band device to access the database to register its location and receive a list of channels 
that are available for it to use. From that point on, the newly registered TV band device must only use the 
television channels that the database indicates are available for it to use and not the channels indicated or 
used by the other TV band device.163 
161 See Report and Order in ET Docket No. 03-133, 18 FCC Rcd 24484 (2003) at Appendix C; see also 
47 C.F.R.  15.202. 
162 In this context, not initialized means that the TV band device has not yet registered with and accessed the 
database to determine a list of available channels. 
163 Because of the relatively low power that TV band devices will be permitted to use, both of the TV band devices 
will be located fairly close to one another. The lists of television channels available for use by the two devices are 
therefore likely to be the same in most cases. There will, however, be cases where a fixed device that obtains its 
internet connection through another fixed device may be located in the service area of a different group of licensed 
stations. This is particularly likely to occur if a fixed device obtains service from another fixed device that itself 
does not have a direct connection to the internet.

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113. Unlicensed TV band fixed devices must also comply with the Commissions RF exposure 
guidelines.164 As Microsoft observes, we recognize that it is likely that the radiating antennas of these 
devices will generally be the same as their receive antennas and therefore be located outdoors and at some 
height above ground. However, there are no requirements that those locations be in areas where they are 
restricted from persons who do not understand that a radiating structure is present and the need to avoid 
that area or minimize the time spent there. Accordingly, we will apply to these devices our exposure 
guidelines for publicly accessible/uncontrolled locations. The maximum permissible exposure (MPE) for 
a 4 W EIRP transmitter operating in the frequency range from channels 5-51 (76 MHz to 698 MHz) 
varies from an exposure level of 0.2 to 0.47 mW/cm2. The required separation distance from people for 
safe exposure when the exposure limit is 0.2 mW/cm2 (the most restrictive limit over the 76 MHz to 698 
MHz range) is about 40 cm, or 15.7. We believe that RF exposure from devices operating at 4 W EIRP 
in this band can be effectively controlled by measures that can be taken by the party installing the device 
to ensure that persons maintain a distance of at least 40 cm from a devices the radiating antenna. We 
therefore will not require that unlicensed TV band fixed devices be subject to our requirements for routine 
evaluation for compliance with our RF exposure guidelines. Rather, we will require that new units of 
such devices be accompanied by instructions on measures to take to ensure that persons maintain a 
distance of at least 40 cm from the device, as well as any necessary hardware that may be needed to 
implement that protection. 
114. As indicated above, we are requiring that all unlicensed fixed TVBDs register with the 
database system. This registration will provide a means of identifying devices in investigations of any 
cases of interference that may arise. We believe that registration with the database system using the online 
method presented in the section below on Database System Requirements will minimize the impact 
of this requirement on operators of fixed unlicensed TV band devices. 
115. The rules we are adopting will allow TVBDs to communicate with each other in various 
network configurations. For example, multiple fixed TVBDs could be organized into a service network 
comprised of a base station and associated customer premises equipment that communicate through the 
base station, as described in the IEEE draft standard. Alternatively, a fixed TVBD could initiate 
communication directly with any other fixed TVBD, without designating any one fixed TVBD as a 
central relay point. The specific technical requirements and standards for fixed devices are discussed in 
the Technical Standards section below. 
3. Personal/Portable Devices 
116. In the Notice and First R&O/Further Notice, the Commission observed that non-fixed 
personal/portable devices generally pose a greater risk of harmful interference to authorized operations 
than fixed devices because the locations where non-fixed devices are used change, making identification 
of both unused TV frequencies and the devices themselves, if they cause interference, substantially more 
difficult.165 It also noted that such devices may not be able to sense transmissions of licensed services as 
well as fixed devices because they will have antennas that are less efficient and may be located in less 
advantageous positions.166 In view of these concerns, the expected ubiquitous use of such devices, and 
the importance of protecting television service, the Commission proposed to limit personal/portable 
unlicensed TVBDs to 100 mW and to require that that they have a permanently attached antenna with a 
maximum gain of 6 dBi, for a maximum EIRP of 400 mW. The Commission also requested comment on 
164 See 47 C.F.R.  1.1307(b). 
165 Id. 
166 See Further Notice at  18.

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whether personal/portable devices should be required to transmit an identifying signal and the information 
to be carried on that signal.167 
117. In the First R&O/Further Notice, the Commission further noted that the IEEE 802.22 
standard under development is limited to fixed point-to-point and point-to-multipoint operations and does 
not address the non-fixed personal/portable class of devices the Commission proposed to allow in the 
Notice. The Commission therefore sought comment on how non-fixed unlicensed devices could operate 
in the TV bands under the different sharing schemes under consideration in this proceeding.168 It further 
requested comment on whether such devices should be subject to routine evaluation for RF exposure. 
118. Harris Corporation (Harris) supports the Commissions proposal to allow 
personal/portable devices to operate with a maximum power of 100 mW and to incorporate a permanently 
attached 6 dBi gain antenna.169 The White Space Coalition also supports a maximum power of 100 mW 
for personal/portable devices, but with a maximum antenna gain of 0 dBi, which is 6 dB less than 
proposed by the Commission.170 The Consumer Electronics Association believes that the maximum 
power for personal/portable devices should be 20 mW with a 0 dBi gain antenna to minimize direct pickup 
interference to TV receivers, while NCTA believes the maximum power should be in the range of 10- 
20 mW to avoid that type of interference.171 Wireless microphone manufacturers recommend reducing 
the proposed power level for personal/portable devices to minimize the possibility of interference to 
wireless microphones. In this regard, ATK Audiotech suggests 50 mW, Telex suggests 20 mW, and 
Shure suggests 10 mW with a maximum antenna gain of 0 dBi.172 These parties did not provide an 
analytical basis for their suggested parameters. 
119. TV broadcasters argue that unlicensed personal/portable devices should not be allowed to 
operate in the TV bands. MSTV/NAB claim that personal/portable devices are not compatible with 
existing operations in the broadcast TV spectrum because no method exists today or the foreseeable 
future for preventing interference from such devices to the reception of DTV services.173 Other broadcast 
interests, including Cox Broadcasting, McGraw-Hill, and Media General, also state that the Commission 
should not allow personal/portable TV band devices at this time due to the potential for interference to 
DTV reception.174 
120. Manufacturers and users of wireless microphones also express concerns about permitting 
personal/portable devices to operate in the TV bands due to the potential for interference to wireless 
microphones. Shure believes that it would be premature to consider allowing personal/portable devices in 
the TV bands because these devices pose a greater risk of harmful interference than fixed devices. It 
states that personal/portable devices are inherently unpredictable for frequency coordination and sharing 
167 See Notice at  22. 
168 See Further Notice at  18. 
169 See Harris Notice comments at 6. 
170 See White Space Coalition Further Notice comments at 5. 
171 See Consumer Electronics Association Notice comments at 5 and NCTA Further Notice comments at 12. 
172 See Telex Notice comments 4 and Shure Notice reply comments at 7. 
173 See MSTV and NAB Further Notice comments at 34. 
174 See Cox Broadcasting Further Notice comments at 4, McGraw-Hill Further Notice comments at 3, and Media 
General Further Notice comments at 3.

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purposes, may be in a less advantageous position for sensing transmission, change locations randomly, 
and are impossible for incumbent users to identify as a source of interference.175 It further notes that 
neither the IEEE nor any other technical group has offered any comprehensive analysis and proposal for 
protecting incumbent operations from interference caused by personal/portable devices.176 The 
Professional Audio Manufacturers Alliance and Audio Technica believe that the Commission should not 
allow personal/portable devices in the TV bands until after it has experience with fixed devices, while 
Grand Ole Opry and Microphone Interests Coalition believe that personal/portable devices are unsuitable 
for the white spaces and should be prohibited.177 
121. Microsoft submits that personal/portable unlicensed TV band devices should be exempt 
from routine evaluation for RF exposure. It states that the appropriate RF exposure context for 
personal/portable devices is for public/uncontrolled exposure from a device with 100 mW transmit power 
and a ./4 vertical antenna. Microsoft indicates that to reach the MPE limit set forth in our rules, an 
individual would have to remain within 1 inch (7 inches for a high power device) of the device antenna 
when the device is operating at full power and 100% duty cycle for a period of 30 minutes. 178 It contends 
that the likelihood of that happening in the real world approaches zero. Microsoft further observes that 
the Commission routinely exempts mobile devices in bands below 1.5 GHz that radiate less than 1.76 
dBW ERP (3.9 dBW EIRP) from environmental evaluation for RF exposure.179 
122. Discussion. We understand the concerns of parties representing broadcast TV and other 
TV band licensees with respect to the potential for interference to their operations from unlicensed 
personal/ portable broadband devices, and are adopting technical requirements for personal/portable 
devices to control interference which are accordingly rigorous. We believe that with the safeguards we 
are adopting, these types of devices can operate successfully on TV white spaces without causing 
interference to licensed services. As we observed previously in this proceeding, personal/portable devices 
pose a greater risk of interference to licensed TV band service because the locations where these nonfixed 
devices are used will change, making the task of determining unused TV frequencies by the devices 
more complicated. In addition, the transitory nature of such devices makes it difficult for others to 
identity the devices if they cause interference. As a number of the commenting parties observe, the fact 
that a non-fixed personal/portable broadband device (e.g., a device installed in laptop computer) is likely 
to be moved around with some frequency is likely to make it difficult for TV and other users to locate the 
device if it causes interference. For example, a device operating indoors for a short period of time in a 
neighborhood might cause interference that disrupts TV service for the households in that neighborhood 
while it operates. Because personal/portable devices will generally operate intermittently and their 
antennas will generally not be located where they are visible, the interference from such operations would 
be very difficult to identify and control. 
175 See Shure Further Notice comments at 6. 
176 See Shure Further Notice comments at 8. 
177 See Professional Audio Manufacturers Alliance Further Notice comments at 8, Audio Technica Further Notice 
comments at 9 and Grand Ole Opry and Microphone Interests Coalition Further Notice comments at 2. 
178 The standards for RF exposure are contained in Section 1.1310 of the rules. See 47 C.F.R.  1.1310. 
179 For the purpose of radiofrequency radiation exposure evaluation, mobile devices are defined as a transmitting 
device designed to be used in other than fixed locations and to generally be use in such a way that a separation 
distance of at least 20 centimeters (7.9 inches) is normally maintained between the transmitter's radiating structure(s) 
and the body of the user or nearby persons. See 47 C.F.R. 2.1091(b). The Commission routinely exempts mobile 
devices in bands below 1.5 GHz that radiate less than 1.5 watts ERP (3.9 dBW EIRP) from environmental 
evaluation for RF exposure. See 47 C.F.R 2.1091(c).

Federal Communications Commission FCC 08-260 
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123. At the same time, we recognize the significant benefits that unlicensed wireless 
communications in other bands have brought to both businesses and consumers using personal/portable 
digital devices and believe that propagation advantages of the TV bands would further enhance the 
capabilities of those products. Accordingly, we have developed a plan that will allow operation of 
unlicensed personal/portable devices in the TV bands in a manner that provides manufacturers and users 
considerable flexibility in design and use of products, subject to conservative controls on their operation 
to protect TV and other licensed services. As discussed below, this plan provides for use of spectrum 
sensing, but at the present time not as the sole means of determining whether channels are occupied or 
unoccupied. We have sought to make the controls and technical requirements of this as simple and as 
reliable as possible to encourage the development of new products and assure the operators of licensed 
services that they will be protected. We are also providing for certification of devices that rely on 
spectrum sensing alone to determine available channels under a separate plan, as discussed in a 
subsequent section. 
124. As discussed above, we will allow personal/portable devices to operate under two 
alternative approaches: Mode I client and Mode II independent. In Mode I, client devices will be under 
control of a fixed or a Mode II personal/portable device that has determined the available channels in the 
area. In Mode II, devices operating independently will use their own internal geo-location/database 
access capabilities to determine the channels available for location in the area. In either mode, the list of 
available channels that can be used by a device will be determined though the geo-location/database 
method. For the reasons indicated above, we are not requiring that personal/portable devices register with 
the database system. 
125. Personal/portable devices operating in either mode will also be required to perform 
spectrum sensing that can detect wireless microphone, TV and other authorized signals at levels as low as 
-114 dBm over the 6-MHz channel bandwidth to determine whether channels are vacant. We believe 
several purposes are served by requiring spectrum sensing. Although spectrum sensing did not perform 
consistently in our testing, we expect it will continue to develop and improve. While the principal means 
of protecting TV service will be through the geo-location and database requirements, sensing can serve as 
a back-up for detecting TV signals inside the protected service areas where there may be errors in the 
database. As such and as further explained below, this function will advise the user of the presence of a 
signal so that they can take appropriate action. We are aware that TV signals are often present at levels 
below -114 dBm within a stations service area and that sensing at this level may not reliably detect TV 
signals in such cases. However, given that the geo-location and database access approach provides a 
reliable means for protecting TV service, we believe that it is not critical that the sensing function be 
capable of detecting signals below the -114 dBm level. Further, while we are establishing provisions to 
ensure that channels are available for operation of wireless microphones, a sensing capability provides at 
least some means to detect such devices that may be operating on an itinerant basis on virtually any 
channel. We find that detection at a level as low as -114 dBm is appropriate for detection of wireless 
microphone signals in a 200 kHz bandwidth. We believe that this level of sensitivity is also acceptable 
detection of ATSC digital signals in a 6 MHz bandwidth and NTSC analog television signals in a 100 
kHz bandwidth as a complement to the geolocation and database requirement. 
126. We will permit personal/portable devices operating in either mode to transmit with up to 
100 mW EIRP. We recognize the concerns of the cable interests that there is a potential for direct-pickup 
interference and their position that power levels should therefore be limited to a lesser value. We 
appreciate that the tests described on our report on direct pick-up interference to three digital cable ready 
receivers and the anecdotal tests performed by our engineers in the laboratory and field in our second 
series of tests of white space developmental devices indicated that there is some potential for direct pickup 
(DPU) interference to cable service from TV white space transmitters. We also note, however, that 
this occurred at relatively close spacings within the users premises and could be corrected by removing 

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consumer-installed splitters and wiring that effectively reduce the shielding to interfering signals as well 
as reduce the desired signal levels available at the TV receiver. Further, when just the cable converter 
box was used to connect directly to the TV receiver, interference declined dramatically and was virtually 
non-existent on the digital tier of channels. Cables systems are rapidly moving to digital technology 
which should further alleviate the potential for interference. Consumers generally should be able to 
correct any interference to their own devices by increasing the separation, re-orienting the devices, or 
using wiring with improved shielding. We also note that, in our tests, with a 10 meter separation between 
devices on separate sides of a wall, such as in a townhouse, the interference did not occur at signals below 
100 mW for two receivers and a bit under 50 mW for a third. The interference was also a function of the 
physical relationship between the devices, such as whether the interfering signal was located towards the 
front or rear of the TV receiver. In addition, as discussed below, we are requiring that TVBDs use 
dynamic power reduction, and in locations in townhouses and apartments where the operating distances 
are apt to be relatively short, the power level would typically be adjusted automatically to less than the 
maximum permitted power of 100 mW. In contrast, reducing the permitted power of the device could 
make it unviable in locations where the separations are greater. Accordingly, we are not persuaded at this 
time that the risk of DPU interference is sufficiently great to warrant a reduction in power that could 
impede the viability of certain TVBD applications. Nevertheless, we will closely monitor for any reports 
of this type of interference and will expect the equipment suppliers to cooperate in helping consumers to 
rectify any such interference. 
127. We are adopting the White Space Coalitions recommendation to limit the EIRP of 
personal/portable devices with antenna gain to a maximum of 0 dBi in either case in order to further 
reduce the potential for interference. That is, if the gain of a devices antenna exceeds 0 dBi, we will 
require a reduction in the maximum transmitter power to below 100 mW by the same amount in dB that 
the antenna gain exceeds 0 dBi. We will further require the antenna to be permanently attached to 
prevent user substitution of higher gain antennas. 
128. We will not require that unlicensed TV band personal/portable devices transmit basic 
identifying information when they are operating. We find that an identifying signal will not be of 
significant value in identifying the source of or, more importantly, resolving any interference that these 
devices might cause. In this regard, the identifying code will not serve to identify a device, its operator, 
or its location as that information will not be recorded in the database system. We also believe that the 
range of potential interference from personal/portable devices will be sufficiently short that any persistent 
interference that might occur from a device that is regularly used at the same location could be resolved 
by traditional methods of local knowledge from those TV viewers receiving the interference and/or 
direction finding. In addition, these devices will operate on a transient basis such that a device could be 
relocated and its interference resolved before steps could be taken to identify and locate the device using 
information transmitted in its signal. 
129. The plan for Mode I client operation by personal/portable devices will protect licensed 
services in a manner similar to the master/client provisions the Commission adopted for unlicensed U-NII 
devices operating in the 5 GHz band and is supported by the various parties, including broadcasters.180 
This approach will allow personal/portable TV band devices to be built into laptop computers and other 
portable devices and operate whenever they are in close proximity to a fixed or Mode II personal/portable 
device or are able to independently perform geo-location and contact the database. Personal/portable 
devices will be allowed to communicate with other personal/portable devices on a master/client basis, 
180 See 47 C.F.R.  15.407(h)(2)(i). Master and client modes are defined in the U-NII compliance measurement 
procedure found in the appendix of the Memorandum Opinion and Order in ET Docket No. 03-122, 21 FCC Rcd 
7672, 7682 (2006).

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with a device that incorporates geo-location/database access and sensing to determine the available 
channels serving as the master unit. Personal/portable devices operating as client devices in such cases 
will again be required to use channels/frequencies as directed by the master device. Devices that both 
make use of geo-location/database access and sensing may, of course, also (and preferably) communicate 
with one another and share their sensing information. 
130. If the user of a personal/portable unlicensed TV band device that does not have a geolocation 
capability intends to operate the device in Mode I as a client to another unlicensed TV band 
device (either a fixed device or a personal/portable device that uses a geo-location/database access 
capability) and the personal/portable device can receive the transmissions of such other TV band device, 
we will allow the personal/portable device to initiate contact by transmitting on either a channel that the 
TV band device with a geo-location/database access capability has transmitted on or on a channel which 
the other device indicates is available for use. The personal/portable TV band device will be required to 
immediately use its communications link with the other TV band device to obtain a list of channels that 
are available for it to use. 
131. Personal/portable devices operating in a Mode II independent basis will protect licensed 
services using the same geo-location/spectrum sensing and database access/registration plan as fixed 
devices. Such devices will be required to obtain a list of available channels at its location from the 
database. 
132. The rules we are adopting will allow personal/portable devices to communicate with each 
other in network configurations over short distances. For example, a Mode II independent device could 
communicate directly with other Mode II independent devices or with several Mode I client devices. We 
will permit personal/portable TVBDs to be used in the operation of mesh networks, only where a means 
is provided to ensure that each device is operating consistent with the channels available at its particular 
location. That is, we will not permit personal/portable devices operating on a client basis to relay 
information from one client device to another unless some means is used to ensure that each device is 
operating within the parameters for its particular location. This will allow use of personal/portable 
devices in that manner and such operation could facilitate the expansion of broadband service in a 
community. Nonetheless, we are concerned and need to ensure that that the range of a mesh network of 
client devices does not extend out to distances where the available channels would change, with the result 
that some licensed services would be subject to interference. 
133. We envision that both the Mode I and Mode II approaches will often be incorporated into 
the same personal/portable device. That is, a personal/portable device could function as a master device 
when it is able to use geo-location/sensing and database access to identify unused TV channels in its area. 
If it cannot rely on these techniques but is near a fixed device or another personal/portable device that can 
act as a master, it could operate in client mode if it makes contact with a master station. 
134. With respect to RF exposure, we first observe that personal/portable TV band devices 
could operate as either mobile or portable devices as defined in Sections 2.1091 and 2.1093 of the 
rules, respectively.181 Under Section 2.1091, a mobile device is a transmitter designed to be used in other 
than fixed locations and to generally be used in such a way that a separation distance of at least 20 
centimeters is normally maintained between the transmitters radiating structure(s) and the body of the 
user or other nearby persons. Such devices that operate on frequencies below 1.5 GHz are subject to 
routine environmental evaluation for compliance with the RF exposure guidelines only if their effective 
radiated power (ERP) is 1.5 watts or more. The 100 mW EIRP limit for personal/portable TV band 
181 47 C.F.R.  2.1091 and 2.1093

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devices is equivalent to 61 mW ERP; therefore personal/portable devices that are designed for operation 
in mobile exposure conditions such that the radiating structure(s) are maintained at distance of at least 20 
centimeters from the body of the user or other persons will not be subject to our requirements for routine 
evaluation for RFE.182 
135. Section 2.1091 provides that a portable device is a transmitter designed to be used so that 
the radiating structure(s) of the device is/are within 20 cm of the user. The MPE standards for such 
devices are specified in terms of the Specific Absorption Rate (SAR) of RF energy by the body as 
specified in Section 2.1093(d). Inasmuch as users of unlicensed TV band devices cannot generally be 
expected to be aware of the potential effects of RFE, we believe it is appropriate to apply the standards for 
general population/ uncontrolled exposure in Section 2.1093(d)(2). Under those standards, the SAR 
limits are 0.08 W/kg as averaged over the whole body, with spatial peak SAR not exceeding 1.6 W/kg as 
averaged over any 1 gram of tissue, except for the hands, feet, wrist, and ankles, where the spatial peak 
SAR shall not exceed 4 W/kg as averaged over any 10 grams of tissue. In order to avoid unnecessary 
SAR testing for low output power personal/portable devices, we find it is desirable to establish an average 
power threshold whereby devices operating below that threshold will not be subject to such testing. In 
developing a threshold, we first observe that SAR is proportional to the average power absorbed in tissues 
and does not generally have clear and direct relationships with either the average or peak power of a 
TVBD. However, the energy absorption characteristics of tissues for energy on frequencies in the 76 - 
698 MHz range, are relatively flat, as compared to higher frequencies (above 1 GHz); therefore, a single 
conservative average power threshold can be sufficient as a threshold for all TVBD frequencies. 
136. Based on the absorption characteristics of tissues in the 76 - 698 MHz range, we are 
applying a source-based time-average output power threshold of 20 mW as the triggering point for routine 
SAR evaluation for personal/portable TVBDs. This standard also allows margin to account for 
simultaneous transmissions by transmitters in the device operating in other frequency bands that may 
increase exposure potentials. Accordingly, personal/portable TVBDs that meet the definition of portable 
devices under Section 2.1093 and operate with time-averaged output of less than 20 mW will not be 
subject to routine evaluation for compliance with the RFE guidelines; such devices that operate with timeaverage 
output power greater than that level will be subject to the routine evaluation requirements. The 
specific technical requirements and standards for personal/portable devices are discussed in the Technical 
Standards section below. 
C. Permissible Channels For Unlicensed Operation 
137. In the Notice, the Commission stated its belief that unlicensed TV band devices should be 
allowed access to the largest practicable number of the 68 television channels. It also indicated that 
certain channels did not appear suitable or appropriate for use by unlicensed devices. In this regard, the 
Commission proposed to exclude unlicensed devices from operating on TV channels 2-4 to avoid 
possible interference to TV interface devices such as VCRs, DVDs, DVRs, satellite and cable boxes that 
operate on or adjacent to those channels.183 It further proposed to exclude unlicensed devices from 
channel 37, which is used for radio astronomy and the wireless medical telemetry service (WMTS), and 
from channels 52-69, which have been reallocated for new non-broadcast, uses. In addition, it tentatively 
concluded that channels 14-20 are not suitable for use by unlicensed devices in markets where they are 
182 EIRP is referenced to a theoretical point source radiator, whereas ERP is referenced to a dipole radiator. Power 
measurements of EIRP are 1.64 (2.15 dB) times higher than measurements of ERP for the same transmit output 
power level. Therefore, 400 mW EIRP is equivalent to 244 mW ERP (400 mW/1.64). 
183 Notice at  33-37.

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used for PLMRS and CMRS operations.184 Using the same criteria specified in the rules for protection of 
land mobile operations from low power TV, TV translator, TV booster, and Class A TV (LPTV) stations, 
the Commission therefore proposed not to allow unlicensed devices to operate within 134 km or 131 km 
from the center coordinates of metropolitan areas where PLMRS/CMRS services operate on co- and 
adjacent channels, respectively.185 With the exception of these channels, the Commission proposed to 
allow unlicensed TV band devices to operate on any unused TV channel. Thus, it proposed to make TV 
channels 5-36 and 38-51 generally available for unlicensed operation and channels 14-20 available in 
locations where they are not used by the PLMRS or CMRS. In the Notice, the Commission also sought 
comment on the possibility of designating one or two locally vacant channels for use only by wireless 
microphones.186 
138. In the First Report and Order and Further Notice, the Commission adopted its proposals 
to exclude unlicensed TV band devices from channel 37 in order to protect radio astronomy and medical 
telemetry, and from channels 52-69 as those channels have been reallocated to new uses.187 With respect 
to channels 14-20, it decided to prohibit personal/portable TV band devices on these channels everywhere 
in order to protect public safety and other PLMRS/CMRS operations, as such devices could be easily 
transported and used anywhere, including within the service areas of PLMRS/CMRS and other licensed 
operations. The Commission did, however, not make a decision on whether to allow fixed unlicensed 
devices to operate on channels 14-20 in areas of the country where those channels are not being used for 
PLMRS/CMRS or other authorized services. It noted that prohibiting operation of fixed TV band devices 
on channels 14-20 everywhere would preclude operation of such devices in many areas where these 
channels are not used since PLMRS/CMRS operations only use one to three channels in 13 metropolitan 
areas and other services on those channels, such as the Offshore Radiotelephone Service, similarly 
operate only in a few areas. The Commission therefore sought additional comment on whether fixed 
unlicensed TV band devices should be allowed to operate on channels 14-20 in areas where those 
channels are not used by PLMRS/CMRS and other operations.188 
139. The Commission sought further comment on whether it should exclude channels 2-4 
from use by TV band devices because of possible interference to TV interface devices such as VCRs, 
DVRs and MVPD terminal devices that typically use those channels in output connections to TV 
receivers.189 In particular, it sought comment on whether TV interface devices would be more susceptible 
184 See 47 C.F.R.  90.305 and 47 C.F.R.  22.625. PLMRS/CMRS base stations must be located within 80 
kilometers (50 miles) of the center of the cities where they are permitted to operate on channels 14-20 (470-512 
MHz), and mobile units may be operated within 48 kilometers (30 miles) of their associated base station or stations. 
Thus, mobile stations may be operated at up to 128 kilometers (80 miles) from the city center. We also note that 
there are numerous licensed land mobile operators, including public safety entities that currently operate, pursuant to 
waiver, on defined channels in channels 14-20 at specified locations outside those markets specifically designated in 
the Part 90 rules. See, e.g., Goosetown Enterprises Inc., 16 FCC Rcd 12792 (2001). 
185 Under this approach, PLMRS/CMRS operations would be protected within a circle of radius 130 kilometers from 
the city center coordinates. This is the area in which such operations are permitted under the rules. As is the case 
for LPTV stations, the field strength from an unlicensed device on a co- or adjacent channel would not be permitted 
to exceed 52 dBu or 76 dBu, respectively, at the 130 km protected contour of the PLMS/CMRS metropolitan area. 
See 47 C.F.R.  74.709(d). 
186 Id. at  38. 
187 First Report and Order and Further Notice of Proposed Rulemaking at  19-21. 
188 Id. at  56. 
189 Id. at  57.

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to interference from low power TV band devices than other TV receivers; on whether the cabling between 
a TV interface device and a TV receiver typically provides adequate shielding from unwanted signals on 
channels 2-4; and the extent to which such signals may be picked-up directly within the TV receiver. It 
also sought comment on how much longer consumers can be expected to use TV interface devices that 
connect to a TV through the tuner (antenna or cable television input) rather than an alternative interface 
connection. A number of parties commented on these issues. In addition, several parties submitted 
comments regarding additional channels on which the operation of TV band devices should be restricted. 
140. In their Petition for Reconsideration, NAF/CUWN ask the Commission to reconsider its 
decision to prohibit personal/portable TV band device operation in channels 14-20.190 They argue that the 
Commission should defer a decision on this issue until it is more familiar with the available technologies 
for mobility. NAF/CUWN is concerned that no parties will develop the necessary technologies to permit 
use of channels 14-20 for mobile devices if the Commission forecloses this possibility now. They 
contend that the Commissions decision to exclude personal/portable devices from channels 14-20 is 
imposing unnecessary costs on the public through an overabundance of caution. 
141. The NAF and the CEA submit that fixed unlicensed TV band devices can operate on 
channels 14-20 without interfering with PLRMS/CMRS operations through the use of geo-location 
capabilities and a database containing the markets where these channels are used.191 These parties submit 
that not allowing use of these channels in other areas would needlessly remove a large amount of white 
space since PLRMS/CMRS operations only make use of one to three channels in a small portion of the 
United States. Motorola suggests that channels 14-20 be reserved for TV band devices used by public 
safety agencies.192 It believed that this would prevent interfering uses and satisfy a great need in the 
public safety community. 
142. The Land Mobile Communications Council (LMCC) argues that unlicensed TV band 
devices should not be allowed to operate on channels 14-20 anywhere in the country.193 The LMCC 
believes that even if these devices are banned from an exclusion zone around the area used for 
PLMRS/CMRS operations, some users of the devices will not adhere to the restrictions. It states that 
there would be no way to identify nonconforming unlicensed devices in the dense urban areas where these 
channels are used. LMCC furthermore submits that spectrum sensing would not be effective in 
identifying PLMRS/CMRS channels because radios in those services are used only intermittently. Los 
Angeles County adds that fixed devices can always be moved to areas where they would interfere with 
PLMRS/CMRS operations.194 Comm Enterprises claims that PLMRS/CMRS use of these channels may 
expand after the end of the digital transition and that such growth warrants prohibiting unlicensed devices 
from operating on them.195 
190 See NAF/CUWN Petition for Reconsideration at 7-8. 
191 See NAF et al. comments at 78; CEA comments at 6. 
192 See Motorola comments at 10-11. 
193See LMCC comments at 9. 
194 See The County of Los Angeles Further Notice comments at 2. 
195 See Comm Enterprises, LLC Further Notice comments at 6.

Federal Communications Commission FCC 08-260 
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143. Most of the commenting parties that address this issue continue to oppose the use of 
channels 2-4 for TV band devices in order to avoid interference with TV interface devices.196 For 
example, CEA states that there is potential to cause interference to the installed base of analog receivers 
which might be connected to digital-to-analog converter boxes or receiving their content from a terminal 
device of a multichannel video program distributor such as cable or satellite that uses channels 3 or 4.197 
However, the NAF appears to suggest that channels 2-4 could be used by TV band devices if shielded 
cables are used to connect the interface device to the TV.198 The National Cable Television Association 
(NCTA) counters that the interference to TV interface devices in fact generally results from leakage into 
the television receiver, so that use of shielded cables would not prevent interference.199 NCTA submits 
that leakage into television receivers will occur on all VHF channels and that TV band devices should 
therefore be limited to only UHF frequencies. 
144. GE Healthcare (GE) requests that TV band devices not be allowed on channels 33-36 
until February 18, 2010 in order to allow medical facilities time to replace grandfathered medical 
telemetry systems that operate on those channels.200 GE and The American Society of Healthcare 
Engineering note that medical telemetry devices that operate on channels 33-36 are currently being sold 
in areas where those channels are vacant.201 GE also argues that stricter spurious emissions limits are 
needed to protect WMTS devices that operate on channel 37. In addition, GE asks that the Commission 
restrict operations of TV band devices on channels 36 and 38 or require that professional installation and 
coordination with WMTS systems to ensure that the emissions in channel 37 are kept below 50 
microvolts/meter at WMTS facilities. GE further requests that we require fixed TV band device operators 
to notify nearby hospitals before beginning operation.202 The White Space Coalition responds that 
granting GEs request to protect channels 33-36 would only serve to encourage more grandfathered 
devices on those channels. 203 GE subsequently submitted an emissions mask for TVBDs that it states 
would address its concerns about adjacent channel overload and spurious emissions interference from 
TVBDs to WMTS devices on channel 37.204 
196 See CEA Further Notice comments at 6; NCTA Further Notice comments at 13-15; Echostar Further Notice 
comments at 2; IEEE 802.18 Further Notice comments at 23-24. 
197 See CEA Further Notice comments at 6. 
198 See NAF et al. Further Notice comments at 83. The NAF notes that the use of channels 2-4 would result in 
significantly more whitespace because these channels are considered undesirable for DTV. Id. 
199 See NCTA Further Notice comments at 13-15. 
200 See GE Healthcare Further Notice comments at 5. As indicated above, wireless medical telemetry devices 
operate on channels 7-13 (174-216 MHz) and channels 14-46 (470-668) MHz on an unlicensed basis under Sections 
15.241 and 15.242 of the rules; WMTS devices operate on channel 37 (608-614 MHz) on a licensed basis under 
Sections 95.1101-1113 of the rules. WMTS devices are also authorized to use the frequency bands as 1395-1400 
MHz and 1427-1429.5 MHz. See 47 C.F.R.  15.241-.242 and 47 C.F.R.  95.1101-.1113. Section 15.37(i) also 
provides that new equipment approvals may no longer be obtained for medical telemetry devices operating under 
Sections 15.241 or 15.242 after October 22, 2002. See 47 C.F.R.  15.37(i). 
201 See GE Healthcare comments at 3; American Society of Healthcare Engineering Further Notice comments at 4. 
202 See GE Healthcare Further Notice comments at 6, 8-9. 
203 See White Space Coalition Further Notice reply comments at 34. 
204 See GE Healthcare ex parte submission of May 6, 2008.

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145. The National Radio Astronomy Observatory (NRAO) requests that we place additional 
limits on channel use by unlicensed TV band devices to protect radio astronomy.205 Specifically, it 
requests that TV band devices be prohibited on channels 4, 5, 36, and 38 in the vicinity of the Very Large 
Array (VLA) radio telescopes and on channel 36 and 38 near the Very Long Baseline Array (VLBA) in 
order to protect radio astronomy operations in bands between channels 4 and 5 and in channel 37.206 In 
addition NRAO requests that the Commission require that all TVBDs operating in the vicinity of certain 
radio astronomy sites such as the National Radio Quiet Zone,206 the individual VLA installations, and the 
VLBA be coordinated with the NRAO. 
146. In its reply comments in response to the First Report and Order and Further Notice, the 
White Space Coalition suggests that unlicensed TV band devices (both fixed and personal/portable) be 
allowed to operate only on unoccupied channels in the range 21-51. The White Space Coalition indicates 
that this plan would avoid any direct pick-up interference problems on VHF channels, accommodate 
public safety operations on channels 14-20 and provide reserved spectrum for operation of wireless 
microphones.207 
147. Shure suggests that the Commission designate six television channels in each market for 
use by wireless microphones.208 Shure notes that wireless microphones can use channels adjacent to 
broadcast television stations, and states that if unlicensed TV band devices were prohibited from using 
adjacent channels, those channels would be available for wireless microphones. It also observes that in 
rural areas there are fewer television stations and hence will be fewer adjacent channels so that wireless 
microphones would be assured of available channels for their use.209 
148. Discussion. As indicated in the Notice, we believe it is important that TV band devices 
be allowed to operate on the largest practicable number of television channels.210 This will maximize the 
opportunities for operation of unlicensed devices in all areas, and will be particularly important for the 
successful implementation of unlicensed devices in areas where the TV bands are congested with other 
services. As discussed throughout this proceeding, however, there are certain channels that are not 
suitable or appropriate for use by unlicensed by TV band devices. Accordingly, as discussed below we 
will allow both fixed and personal/portable unlicensed TV band devices to operate on channels 21-36 and 
38-51. In addition, we will allow fixed devices to operate on channels 2 and 5-13 and channels 14-20 
outside of areas where PLMRS/CMRS services operate.211 Thus, fixed TVBDs will be allowed to operate 
on a total of 48 channels and personal/portable TVBDs will be allowed to operate on 30 channels. In 
prohibiting personal/portable devices from operating on channels 14-20, we are maintaining our previous 
decision not to allow personal/portable devices on those channels and thereby denying NAF/CUWNs 
request for reconsideration of that decision. 
205 See NRAO Further Notice comments at 8. 
206 See Section 15.712(h) of the rules in Appendix B for the locations of these radio astronomy facilities. 
207 See White Space Coalition Further Notice reply comments at 29-31. 
208 See Shure Further Notice reply comments at 8. 
209 See Shure Further Notice comments at 12-14. 
210 See Notice at  17. 
211 Conversely, fixed devices will be excluded from channels 3 and 4, channels 14-20 in areas where 
PLMRS/CMRS services operate, and channel 37; personal/portable devices will be excluded from channels 2-20 
and channel 37.

Federal Communications Commission FCC 08-260 
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149. We will prohibit operation of TVBDs on channels 3 and 4 in order to prevent direct pickup 
interference to TV interface devices such as VCRs, DVRs, and MVPD terminal devices. Those 
devices typically modulate their output signals on TV channels 3 or 4 and pass the signals to a receiver 
through a shielded cable. Depending on the effectiveness of the shielding on TV interface devices, 
modulation and, where included, TV reception circuitry, emissions from an unlicensed TV band device 
on channels 3 or 4 could cause interference to the output of the TV interface device. In addition, as 
indicated in the tests conducted by our engineers, TV receivers themselves appear to be more susceptible 
to direct pick-up interference on channels 3 and 4. While there was not a significant amount of other new 
empirical information in the record on the susceptibility of TV interface devices or TV receivers, NCTA 
does provide credible information indicating that most analog TV receivers have been seriously lacking in 
shielding at channels 3 and 4.212 
150. We also have no information that the shielding of new DTV receivers and TV interface 
devices has improved significantly. In addition, we note that such devices are invariably used with 
shielded cables, and we see no indication that the shielding on the connecting cables used with such 
devices is the principal source of the susceptibility to interference; rather, the potential for interference 
arises from inadequacies in the shielding within the devices themselves. Thus, we see no basis for 
concluding that such interference can be prevented through the use of shielded cables as NAF suggests. 
In view of the fact that there are many millions of VCRs, DVDs, DVRs, satellite and cable set-top boxes 
now in service, interference to the operation of those devices from unlicensed TV band devices 
interference could result in widespread disruption of consumers video services. We therefore find that it 
necessary to take a cautious approach and place channels 3 and 4 off-limits to unlicensed TV band 
devices. 
151. One of our considerations in this matter is to ensure that channels remain available for 
use by wireless microphones. While we are aware that many wireless microphones are now operated, 
without the required license, we nonetheless understand the important function that wireless microphones 
serve and find that it is in the public interest to preserve spectrum in the TV bands that is available for 
their use. As discussed below, we conclude that the Coalitions suggestion to preserve unoccupied TV 
channel space below channel 21 for wireless microphones is an appropriate solution for providing 
spectrum to meet wireless microphone needs while also satisfying the needs of unlicensed TVBDs.213 We 
also recognize that there is interest by WISPs and others in using fixed TVBDs to reach rural and other 
underserved areas that are at distances not reachable with lower power devices operating at higher 
frequencies. The VHF and lower UHF bands appear particularly well suited for those purposes. We 
believe that if we restrict use of channels 5-20 to fixed devices on those channels to communications with 
other fixed devices we can meet the needs of those desiring to provide service at a distance and also limit 
the number of TVBDs that could potentially conflict with wireless microphone use. 
152. We also remain concerned about possible interference from unlicensed TVBDs to public 
safety and other important communications operations in the PLMRS. While the geo-location/database 
and client operation provisions of the rules we are adopting herein will serve to provide a high degree of 
212 NCTA Further Notice comments at 10-11. NCTA includes in Appendix II of its comments a study of the 
shielding effectiveness analog TV receiver performed by Carl T. Jones Corporation in 1993, Customer Premises 
Equipment Performance and Compatibility Testing, Section 3. This study examined the direct-pickup performance 
of 35 television sets that comprised a representative sample of various manufacturers and models and found that the 
television receivers provided very poor shielding at the low VHF channels. 
213 We emphasize that in this proceeding we are not altering the channels on which wireless microphones may 
operate.

Federal Communications Commission FCC 08-260 
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assurance that PLMRS/CMRS, Offshore Radiotelephone Service and other authorized services on 
channels 14-20 are protected, we continue to believe that the nomadic nature and expected high numbers 
of personal/portable devices poses some potential for interference to those services. Given that parties 
who are expected to manufacture TVBDs anticipate that channels 21-51 will provide adequate spectrum 
resources for their products, we choose to be conservative in protecting the PLMRS/CMRS services and 
will prohibit personal/portable devices from channels 14-20 and are therefore denying NAF/CUWNs 
request for reconsideration in this regard. We do not have the same concerns with regard to fixed pointto-
point or point-to-multipoint operations that will be fewer in number and remain in place. Accordingly, 
we will only allow fixed devices that communicate with other fixed devices to operate on channels 5-20. 
153. We will therefore allow operation of fixed TV band devices on channels 14-20 in those 
areas of the country where the channels are not being used for PLMRS/CMRS or other authorized 
services, including the Offshore Radiotelephone Service. As we describe elsewhere in this Second Report 
and Order, we are requiring that fixed TV band devices avoid operating on channels that will interfere 
with PLMRS and CMRS operations. The TVBD database will contain information on the locations and 
channels used for PLMRS/CMRS, the Offshore Radiotelephone Service and other authorized services to 
prevent TV band devices from operating on the channels used by those services.214 
154. We will allow all unlicensed TV band devices to operate on unoccupied television 
channels in the channel range 21-51, with the exception of channel 37. This will provide a large number 
of channels within the same area of the spectrum that can potentially be used for unlicensed TVBDs, and 
thereby maximize the opportunities for operation of unlicensed devices in all areas. Allowing TVBD 
operations on two large blocks of UHF spectrum will increase the likelihood of locating blocks of 
available channels. This plan would also comport in large degree with the channel availability plan for 
TVBDs suggested by the White Space Coalition. 
155. We reaffirm our decision not to allow TVBDs to operate on channel 37 in order to protect 
radio astronomy and WMTS operations. As indicated above, medical telemetry devices used in hospitals 
and other healthcare facilities also operate on other channels in the television bands on a noninterference 
basis under Part 15 of our rules. As discussed below, we are adopting strict out-of-band emissions limits 
for TVBDs operating on channels 36 and 38. We are applying these to both fixed and personal/portable 
TVBDs. Given these very strict limits, we do not believe it is necessary to require coordination fixed 
TVBDs with medical facilities. 
156. We understand the NRAOs concerns with respect to protection of radio astronomy 
operations from potential interference from TVBDs and also recognize that there is need to protect the 
Table Mountain Radio Receiving Zone that is used by the Federal Government for sensitive radio 
research. To ensure that these sensitive facilities are protected from potential interference, we will not 
allow unlicensed TV band devices to transmit on any channel within and in the vicinity of radio 
astronomy observatories. These facilities include the Allen Telescope Array, the Arecibo Observatory 
(which includes the islands of Puerto Rico, Desecheo, Mona, Vieques and Culebra), the Green Bank 
Telescope (which is in the National Radio Quiet Zone), the Very Large Array (VLA) and the Very Long 
Baseline Array (VLBA) stations. We will also prohibit TV band devices from operation on any TV 
channel within and in the vicinity of the Naval Radio Research Observatory (which is in the National 
Radio Quiet Zone) and within the vicinity of the Table Mountain Receiving Zone to protect the sensitive 
214 If use of these channels by PLMRS/CMRS and other services is expanded in the future, we will require that the 
database be updated to include those expansions.

Federal Communications Commission FCC 08-260 
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radio research efforts at those facilities.215 As recommended in the NTIA letter, we will apply these 
restrictions to operation of both fixed and personal/portable unlicensed devices within 2.4 km of the 
coordinates of the radio astronomy observatories, the Naval Radio Research Observatory and the Table 
Mountain Radio Receiving Zone. We do not find it necessary to restrict operation of TVBDs within the 
boundaries of National Radio Quiet Zone except within and in vicinity of the two research facilities 
therein. We observe that these facilities are generally located in less populated areas so that prohibiting 
TVBDs from operating in the local areas around them will affect a relatively few potential users of 
TVBDs.
157. We also recognize that many wireless microphones now in licensees inventories are 
configured to operate on UHF channels and that manufacturers and users of those devices will need to 
migrate their systems that are currently configured for operation on channels in the 700 MHz range 
(channels 52-69) to channels within the DTV core spectrum. These considerations will necessitate access 
to and use of a significant number of the UHF channels by wireless microphones. In a recent ex parte 
statement, Shure requested that we reserve several channels in the UHF spectrum for wireless 
microphones.216 In general, we believe that it is not necessary to reserve spectrum to protect fixed uses of 
wireless microphones such as studios because those facilities may register with the database. However, it 
is not practical to register the locations of electronic news gathering crews and other media activities that 
operate on an itinerant basis. We believe that our decision to prohibit personal/portable TVBDs from 
operation on channels below channel 21 will generally ensure that an adequate number of UHF channels 
are available for interference free operation of these important itinerant wireless microphone uses. 
However, the number of UHF channels available will be more restricted in markets where there are 
PLMRS/CMRS operations in addition to TV and other authorized uses. We will therefore reserve two 
channels where TVBDs will not be permitted in each of the markets where PLMRS/CMRS operations are 
present in order to preserve spectrum for wireless microphone operation. For such cases, we are adopting 
Shures plan that the reserved channels in each market be the first channels open on either side of channel 
37. For example, if channels 36 and 39 were used by local TV stations, the reserve channels would be 
channels 35 and 38. The reservations of these channels will be recorded in the database. 
D. Protection of Broadcast Television and Other Services 
158. In this section, we describe the technical criteria that will be used for determining when a 
TV channel can be considered vacant for the purpose of allowing operation of an unlicensed device on 
that channel. We first address full service TV stations, which will all operate with digital signals after the 
end of the DTV transition, and low power TV stations, which may be either analog or digital after the end 
of the transition because there is as yet no requirement for analog low power TV stations to convert to 
digital by a specific date. We also address the specific criteria to be used for protection of other licensed 
services that use the TV bands, including the PLRMS/CMRS, cable headends and translator receive sites, 
the Offshore Radiotelephone Service, and wireless microphones and other Part 74 services. 
159. Protection of TV services. Full service TV stations and Class A TV, low power TV, TV 
translator and TV booster stations are generally protected from interference within defined signal 
contours. The signal level defining a television stations protected contour varies depending on the type 
215 See letter of March 1, 2005 from Frederick R. Wentland, Associate Administrator, Office of Spectrum 
Management, National Telecommunications and Information Administration to Edmond J. Thomas, Chief, Office of 
Engineering and Technology, Federal Communications Commission (NTIA letter). 
216 See ex parte submission of Shure

Federal Communications Commission FCC 08-260 
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of station, e.g., analog or digital TV, and the band in which a TV station operates.217 Different protected 
contour values are specified for both analog and digital stations that operate in the low VHF band 
(channels 2-6), the high VHF band (channels 7-13) and the UHF band (channels 14-69). In the Notice, 
the Commission proposed to use the criteria from the Part 73 and Part 74 rules to define the areas that 
unlicensed TV band devices must protect from harmful interference.218 The Commission proposed to 
require that all such unlicensed operations protect TV service within the contours defined by these 
criteria, which are set forth in Table 1: 
Table 1 
Criterion for Definition of TV Station Protected Contours 
Protected contour219 
Type of station 
Channel Contour 
(dBu) 
Propagation 
curve 
Low VHF (2-6) 47 F(50,50) 
Analog TV High VHF (7-13) 56 F(50,50) 
UHF (14-69) 64 F(50,50) 
Low VHF (2-6) 62 F(50,50) 
High VHF (7-13) 68 F(50,50) 
Analog Class A, 
LPTV, translator 
and booster UHF (14-69) 74 F(50,50) 
Low VHF (2-6) 28 F(50,90) 
Digital TV High VHF (7-13) 36 F(50,90) 
UHF (14-51) 41 F(50,90) 
Low VHF (2-6) 43 F(50,90) 
Digital Class A High VHF (7-13) 48 F(50,90) 
UHF (14-51) 51 F(50,90) 
160. The Commission proposed to prohibit fixed/access devices from operating on the same 
channels used by TV services (co-channel) and on the first adjacent channels to channels used by TV 
services (adjacent channels).220 It also proposed to prohibit personal/portable devices only from operating 
co-channel to channels used by TV services. The Commission indicated that it believed that the potential 
for harmful interference to adjacent channel television operations from personal/portable devices (which 
would operate with lower power) would be sufficiently low that it would not need to impose adjacent 
channel restrictions on these devices. 
161. Whether or not interference to TV reception occurs depends on the desired-to-undesired 
(D/U) signal ratio needed for acceptable service. This D/U ratio will vary depending on the type of 
station and the nature of the undesired signal. In the Notice, the Commission stated that it expected the 
217 As indicated above, the protected contours are defined by 47 C.F.R.  73.683(a) for analog TV stations, 47 
C.F.R.  73.6010(a) for Class A TV stations, 47 C.F.R.  74.707(a)(1) for low power TV, TV translator and TV 
booster stations, 47 C.F.R.  73.622(e) for digital TV stations, 47 C.F.R.  74.792 for digital low power TV and TV 
translator stations, and 47 C.F.R.  73.6010(d) for digital Class A stations. 
218 See Notice at  29-32. 
219 The methodology for determining station protected contours and the propagation curves are described and 
presented in Sections 73.684 and 73.699 of the rules. See 47 C.F.R.  73.684 and 73.699. 
220 See Notice at  30. Adjacent channels are the first channels immediately above and below the channel on which 
a TV station operates.

Federal Communications Commission FCC 08-260 
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signals from unlicensed devices to appear noise-like and that the carrier-related interference 
mechanisms that can affect analog television would not occur.221 Given the expected noise-like character 
of signals from unlicensed devices that would make them appear similar to DTV signals, the Commission 
proposed to use the same protection criteria that are currently specified in the rules for digital 
television.222 These criteria are set forth in Table 2: 
Table 2 
TV Interference Protection Criteria 
Protection ratios 
Type of station Channel 
separation 
D/U ratio 
(dB) 
Co-channel 34 
Upper adjacent -17 
Analog TV, Class A, 
LPTV, translator 
and booster Lower adjacent -14 
Co-channel 23 
Digital TV and Upper adjacent -26 
Class A Lower adjacent -28 
162. The Commission proposed to require that these service and protection criteria be used in 
conjunction with appropriate computational software, including use of the Commissions propagation 
curves, and a television station engineering database for coordination and deployment of unlicensed 
fixed/access devices.223 It also proposed not to apply the adjacent channel D/U criteria to fixed/access 
devices between channels 4 and 5, channels 6 and 7, and channels 13 and 14 because of the frequency 
separations that exist between those channels.224 That is, those channels are not actually on adjacent 
frequencies.225 While the commenting parties generally agree on the need for limitations on the use of 
both fixed and personal/portable devices to protect co-channel operations and for higher power fixed 
devices to avoid operating on channels adjacent to those used by TV services, there was disagreement on 
whether personal/portable devices should be permitted to operate on channels adjacent to those used by 
TV services.226 The White Spaces Coalition argues that personal/portable devices should be allowed on 
channels adjacent to occupied channels, and that transmit power control combined with over-the-air 
sensing can ensure that personal/portable devices comply with the mandated D/U ratios for protection of 
licensees on adjacent channels. It further states that an outright ban on adjacent channel use is not 
necessary or advisable and would only create an artificial scarcity of white spaces in congested areas.227 
On the other hand, MSTV/NAB holds that any operation of a TV band device on a TV stations first 
adjacent channel will harm reception. They calculate that operation of a 100 mW device on a first 
221 See Notice at 10032. 
222 See 47 C.F.R.  73.623(c). 
223 See Notice at  31. 
224 The frequency separation between channels 4 and 5 is 4 MHz, between channels 6 and 7 is 86 MHz and between 
channels 13 and 14 is 254 MHz. 
225 The frequencies used for the individual television channels are set forth in Section 73.603 of the rules. See 47 
C.F.R.  73.603. 
226 See IEEE 802.18 Further Notice comments at 9, and MSTV/NAB Further Notice comments at 16. 
227 See White Space Coalition Further Notice comments at 15.

Federal Communications Commission FCC 08-260 
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adjacent channel could cause interference at distances up to 780 meters, and that a 400 mW device on an 
adjacent channel could cause interference at distances up to 1.5 kilometers.228 
163. A number of parties express concern that the proposed rules would not adequately protect 
against interference to broadcast services because viewers may be able to receive service outside of 
stations protected contours. Low power TV and TV translator operators express concern that the 
proposals would protect their stations to a higher field strength level, and therefore a relatively shorter 
service distance, than full service broadcasters, while viewers who depend on low power stations can 
receive service well beyond the specified protected contour.229 The Society of Broadcast Engineers 
(SBE) states that the Notice overlooked the fact that Part 74 allows operation of broadcast auxiliary links 
from temporary sites for up to 720 hours per year, and that no provisions were made for special temporary 
authorization (STA) of broadcast auxiliary links on TV channels.230 
164. Some commenting parties indicate concerns over the methodology that will be used to 
calculate stations protected contours and the required separation distances from unlicensed devices. 
Several parties state that the Commissions propagation curves by themselves are not sufficiently accurate 
to predict service and that the methodology in OET Bulletin No. 69 should be used.231 Parties also 
question whether the proposed D/U ratios are appropriate. IEEE 802 believes that the D/U ratios may 
need to vary depending on the type of modulation used by the desired and undesired emitters, while 
Cohen, Dippell and Everist (CDE) believes that the Commission should update the ratios for TV band 
devices if the Part 73 D/U ratios are modified based upon studies of the current generation of DTV 
receivers.232 
165. Discussion. We will require TV band devices to protect both full service and low power 
TV services from interference within the protected contours specified in the rules for full service TV 
stations. That is, TV band devices will be required to protect low power TV services their 41 dBmV/m, 
the same threshold of service they protect for full service TV stations. The Commissions decision to 
establish higher protected service thresholds for low power stations was a compromise between providing 
a reasonably sized service area for the communities expected to be served by LPTV stations and 
accommodating the large number of expected LPTV stations.233 However, we recognize that that many 
228 See MSTV/NAB Further Notice comments at 16. 
229 For example, see National Translator Association Notice comments at 1, Entravision Holdings comments to the 
Notice at 2, and Community Broadcasters Association Notice comments at 5. We note that full service TV 
stations, which are subject to the public service requirements of Part 73 of the rules, 47 C.F.R. Part 73, are also 
sometimes referred to as full power stations; however in some cases low power stations actually operate with 
higher power and to service larger areas than some full service stations. 
230 See SBE Notice comments at 3. 
231 See Entravision Holdings Notice comments at 3, National Translator Association Notice comments at 1, Syncom 
Media Group Notice comments at 1, and Pikes Peak Broadcasting Company Notice comments at 1. 
232 See IEEE 802 Notice comments at 15 and CDE Notice comments at 6. 
233 See Report and Order in BC Docket No. 78-253, 51 R.R. 2nd 476 (1982). Section 74.792 provides that the 
protected contours of digital low power and TV translator stations are: 43 dBu on channels 2-6, 48 dBu on channels 
7-13 and 51 dBu on channels 14-69, see 47 C.F.R.  74.792(a). The same contour values were adopted for analog 
Class A TV stations in view of the provision in the Community Broadcasters Protection Act of 1999 (which enabled 
the Class A service) to preserve the service areas of those LPTV stations that qualified to be upgraded to Class A 
status. The LPTV and Class A TV digital contour values were chosen to yield digital service areas of roughly 
comparable size to analog LPTV areas. These signal levels compare to the full service television protected service 
(continued.)

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people at locations beyond the specified protected contours for low power TV stations can readily receive 
and do rely on over-the-air reception of those services (Class A, LPTV, translators and boosters). 
Because we do not wish for viewers who rely on low power TV services to lose service as a result of 
interference from unlicensed TV band devices, we are requiring TV band devices to provide the same 
level of protection to low power services that they do to full service TV stations. We emphasize that the 
application of the full service digital TV service thresholds to low power stations herein only applies with 
respect to TVBDs; we are not altering the low power digital TV service thresholds in any other context or 
application under our rules. 
166. We recognize that in some instances viewers receive TV service off-the-air at locations 
beyond the protected contours specified for full service stations. However, the protected contours 
generally define the practical limit of where TV service can be received by most people, particularly for 
digital TV service which is not viewable at all below a certain signal level. Beyond those contours, we do 
not consider service to be present and thus protected. We will therefore base the required separation 
between TV band devices and full and low power TV stations on the protected contours specified for full 
service TV stations. We note that TV receive antennas used in weak signal areas near the edge of a 
protected contour need to be high gain, and therefore highly directional, mounted on high masts and 
aimed toward the TV station being received. While it is possible that a TVBD could be within the 
reception pattern of such antennas, we believe that in most cases they will be in locations under those 
patterns and thus their signals will be attenuated relative to those of the desired television signals. These 
factors will help minimize the likelihood of interference to persons receiving weak over-the-air signals. 
167. We will require TV band devices to protect full service and low power TV reception 
within their own contours using the proposed D/U ratios. We note that the protected contours for low 
power stations, at which the C/U ratios will apply, are generally much smaller in distance from the 
transmitter than for full service stations. These D/U ratios are specified in the rules to establish 
definitions of service and protection rights among stations consistent with the need to provide for 
adequate service to viewers and the considerations of the Commissions overall responsibilities for 
managing the radio spectrum. We believe it is reasonable and appropriate to continue to apply these same 
service and rights definitions with respect to unlicensed devices. None of the commenting parties argue 
that we should use less stringent standards for protection. We note the concerns of IEEE 802 and CDE 
with regard to the facts that the susceptibility of TV receivers to interference from unlicensed TVBDs 
could vary depending on the transmission methods used by such devices and that the receiver tests have 
indicated that the performance may be different from the standards in the rules. We do not expect that the 
susceptibility of TV receivers with respect to unlicensed TVBDs will vary much, if at all, from their 
susceptibility to interference from undesired TV signals, as these devices are expected to operate with 
signals that have wide bandwidth, noise-like characteristics similar to those of DTV signals. In the case 
of devices that use less than the same bandwidth as a DTV signal, we would expect the susceptibility of 
receivers to interference from such devices to be relatively lower than from wider bandwidth signals. 
168. As proposed, and consistent with the rules for full service and low power TV stations, the 
protected contours of full service and low power digital TV stations will be calculated using the F(50,90) 
curves, and the protected contours of low power analog TV stations will be calculated using the F(50,50) 
curves.234 Because we are not permitting fixed or personal/portable TV band devices to operate in the 
same channel as a TV station within the stations protected contour, the coverage prediction elements in 
(Continued from previous page) 
thresholds of 28 dBu on channels 2-6, 36 dBu on channels 7-13 and 41 dBu on channels 14-69, see 47 C.F.R.  
73.622(e). 
234 As the Commission previously decided, TVBD devices will not be permitted to operate until after the end of the 
DTV transition when full service analog broadcasting ceases.

Federal Communications Commission FCC 08-260 
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OET Bulletin No. 69 that predict locations within that contour where service might not be available are 
not applicable.235 
169. We recognize and encourage TV receiver performance standards-setting by industry. 
While we do not have regulations for the sensitivity and immunity performance of TV receivers, we are 
encouraged that manufacturers have designed their products to performance levels that generally meet 
industry-developed standards, recognizing their perceptions of what is acceptable to the market. With 
regard to TV receiver rejection of undesired signals on first-adjacent channels, we note that ATSC 
Standard A/74 specifies a ratio of -33 dB, fully 5 and 7 dB more stringent than our planning factor values, 
and that our tests of DTV receiver performance demonstrate that those improved selectivity values are 
included in consumer receivers and set-top boxes. We therefore use the A/74 value in our analysis of the 
interference potential of TVBDs. 
170. We are adopting our proposals to prohibit unlicensed devices from operating co-channel 
to a TV station and fixed devices from operating on a channel adjacent to a TV station in order to protect 
the TV service from interference. After further consideration, we have also decided to allow limited 
operation of personal/portable operation on channels adjacent to a TV station. Our analyses underlying 
these decisions and the rules for operation of personal/portable devices on adjacent channels are set forth 
below.236 We also recognize that prohibiting fixed devices from operating on first adjacent channels will 
have the effect of limiting the number of channels that are available for use by those devices in some 
markets. We will remain open to possible solutions for operating the higher power fixed devices on 
adjacent channels and will revisit this matter if such a solution is developed. We therefore encourage 
interested parties to continue to explore possible options for operating on first adjacent channels that will 
not increase the potential for interference to television service and to submit them for our consideration 
when they have reach a state of development that will allow for a proper evaluation. 
171. Adjacent channel interference. The proposed D/U ratios for adjacent channel protection, 
which are taken from ATSC Recommendation A/74, are 33 dB for both the lower and upper adjacent 
channels, respectively. An interfering signal on a first adjacent channel would have to be that amount in 
dB higher than the desired signal to cause interference to TV service. Interference could occur whenever 
an adjacent channel TVBD signal is -51 dBm or higher.237 We use the same TV reception models 
described above for analyzing the potential for TVBDs to cause co-channel interference to TV reception 
to examine the potential for TVBDs to cause adjacent channel interference to TV reception. We also use 
two typical models of DTV indoor and outdoor reception and TVBD operation to evaluate the potential 
for interference from adjacent channel personal/portable devices to DTV reception. 
172. In the case of a fixed TVBD in free space, a 4 W EIRP signal (36 dBm) impinging on a 
standard DTV receiving system (OET-69 parameters) at an antenna separation of 16 meters 
(approximately 50 feet, a reasonable distance between rooftop mounted TV and TVBD fixed antennas on 
adjacent structures) would produce a receive carrier level of -8.1 dBm. Assuming that the fixed TVBD 
signal is at an azimuth in the main beam of the TV receive antenna, interference could occur to TV 
service at any location where a TV signal is -51 dBm or less on a first adjacent channel. Under that 
235 The principal function of OET Bulletin No. 69 is to calculate the area served by a DTV station. The OET 
Bulletin No. 69 method calculates the protected contour of a station as part of the prediction method , and it refers to 
the methods in the rules for calculating a TV stations protected contour, i.e., the F(50,90) curves for digital TV 
stations and the F(50,50) curves for analog TV stations. 
236 These analyses reflect the scenarios for reception of TV. 
237 As stated above, the threshold signal level for digital TV service in the UHF band is -84 dBm at the terminal of a 
DTV receiver. Thus, using the 33 dB D/U for adjacent channel protection, -84 dBm + 33 dB yields an adjacent 
channel signal threshold of -51 dBm.

Federal Communications Commission FCC 08-260 
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criterion for TV signal strength (-28 dBm is typically considered a relatively strong TV signal and -53 
dBm is considered a medium TV signal), this essentially means that adjacent channel interference from a 
fixed TVBD could occur almost anywhere within a stations service area. Therefore, at this time, we are 
only prepared to permit fixed TVBDs on channels that are not first adjacent to a TV channel. 
173. With regard to personal/portable TVBDs, we first consider indoor reception. In general, 
we believe that the TVBD and a nearby DTV receiving antenna would not be located such that free space 
propagation conditions would apply. That is, there will generally be scattering objects (e.g., furniture, 
persons, fixtures, conductive or dielectric constituents of wall and/or floor construction) within the 
Fresnel ellipsoid about the ray between the two antennas.238 Thus, we find that the variation with distance 
for indoor propagation is generally greater than the distance squared result applicable to free space and we 
therefore assume a distance variation having an exponent of 2.5. At the -84 dBm threshold for DTV 
service, interference could occur whenever an undesired signal is higher than -51 dBm on a first adjacent 
channel. In the indoor scenario, a 100 mW (20 dBm) TVBD signal at 10 meters (53 dB of non-free space 
attenuation) and after 10 dB of wall attenuation, and 3 dB of polarization mismatch i.e., -46 dBm, would 
exceed that level by 5 dB. In other words, that signal level would likely not cause interference in a 
neighboring residence or office, except at locations only where DTV signals are relatively weak indoors, 
i.e., where DTV signals are at or below -79 dBm. 
174. We next consider outdoor TV reception and an outdoor TVBD. As indicated above, at 
the -84 dBm service threshold, interference could occur whenever an undesired signal is higher than 
-51 dBm on a first adjacent channel. We again use 16 meters as the horizontal distance between the 
TVBD and the outdoor antenna and this results in a slant range distance between the two of about 18 
meters (60 feet) for a signal strength of -28 dBm (53 dB of free space attenuation).239 We consider that a 
personal/portable TVBD near ground level would be outside of the main receive pattern of the TV 
antenna, so that instead of receiving 10 dBd gain, the devices signal might only receive -2 dBd gain. We 
again assume 3 dB of polarization mismatch. Under these conditions, the TVBD signal level at the TV 
receiver would be -40 dBm. That signal level would not cause interference to the outdoor DTV reception 
of a neighboring residence or business at locations unless DTV signals are at or below -73 dBm, i.e., at 
fairly low levels. 
175. We also consider outdoor TV reception and an indoor TVBD. Again, at the -84 dBm 
service threshold, interference could occur whenever an undesired signal is higher than -51 dBm on the 
first adjacent channels. Using the 16-meter horizontal separation distance, and -2 dBd gain of the TV 
antenna in the direction of the TVBD, and including 13 dB of building penetration loss and 3 dB of 
polarization mismatch, the signal level of the TVBD signal would be -53 dB, which is below the 
threshold of interference. 
176. We believe that if the EIRP of these devices is limited to 40 mW and out-of-band 
emissions are properly controlled, as described below, these devices can operate on first adjacent channels 
to TV stations without posing an undue risk of interference to TV service. In particular, a 40 mW power 
limit would reduce the signal strength of a TVBD by 4 dB from the maximum allowed 100 mW and 
thereby provide adequate protection for indoor DTV reception from TVBD interference on both the first 
238 A Fresnel zone or ellipsoid is defined as the area around the visual line-of-sight into which radio waves spread 
after they leave the antenna. Radio waves reflecting off objects within this zone generally arrive out of phase with 
signals that travel directly. The effect is a reduction in received signal strength compared to radio transmissions 
through an unobstructed Fresnel zone. 
239 For the distance between the personal/portable device and the rooftop TV antenna, we assumed the antenna is 
8 meters above the device at one meter and that the rooftop antenna is separated horizontally by 16 meters. We then 
calculated the slant-range distance between the two locations.

Federal Communications Commission FCC 08-260 
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upper adjacent channels and marginal protection for outdoor DTV reception from such TVBD signals. 
We understand that the proponents of personal/portable TVBDs believe that more power is needed for 
those devices to operate on a mobile basis. However, from our analysis above we are concerned that if 
those devices were to operate at higher power the likelihood of interference to TV service would increase 
significantly. 
177. We also observe that additional considerations will serve to further minimize the 
potential for a personal/portable TVBD operating at 40 mW to cause interference to adjacent channel 
DTV reception. First, the out-of-band emissions mask we are adopting for TVBDs is much more 
stringent in the first adjacent channels than the DTV emissions mask on which the adjacent channel D/U 
protection ratios in the rules were based. Out-of-band emissions constitute co-channel interference in a 
first adjacent channel that cannot be addressed by receiver selectivity. Reducing those emissions will 
decrease the interference potential of first adjacent channel TVBD signals to some degree. Second, the 
DTV Receiver Study prepared by our Laboratory indicated that DTV receivers on the market are typically 
able to handle adjacent channel signals at levels higher even than the -33 dB value in ATSC 
Recommendation A/74. That study found that the median adjacent channel D/U ratio for the sampled 
receivers was -38 dB when the desired DTV signal was near the threshold level for service.240 Finally, we 
observe that nearly all outdoor TV receiving antennas are horizontally polarized, while all antennas 
submitted for the prototype TVBDs were vertically polarized. It can be expected that some polarization 
mismatch beyond the assumed value of 3 dB will occur, particularly in the situation when both TVBD 
and TV antenna are located outdoors, reducing the level of the TVBD signal at the TV receiver. Thus, 
while we recognize that there will be variation in the propagation paths between DTV receivers and 
adjacent channel TVBD transmitters and that a minority of DTV receivers may perform at adjacent 
channel D/U ratios closer to those in the rules, we believe that this solution will provide adequate 
protection against TV interference when personal/portable devices operate on adjacent channels. 
178. We observe that several commenters, including among others Google and Motorola, 
submitted comments stating that adjacent channel operations by fixed devices is possible. Google suggest 
that we allow operation of fixed TVBDs on channels adjacent to TV channels using variable transmit 
power up to 1 watt, where actual allowed power would be determined based on a formula and the use of a 
prediction of TV station signal levels using geolocation and the TVBD database.241 Similarly, Motorola 
supports using D/U ratios to protect TV adjacent channel TV operations and requests that TWVS devices 
be permitted to vary power depending on the adjacent channel TV signal strength.242 We believe that 
these methods may have merit in providing for more flexible operations of TVBDs. We agree in 
principle that fixed TVBDs could operate on an adjacent channel where the adjacent channel signal 
level is strong and an adequate margin is established to ensure against harmful interference to nearby 
viewers. However, we note that such approaches to protecting adjacent TV channels are predicated 
on using an appropriate means to predict the adjacent channel signal strength at each location. 
Propagation models that are currently available generally have a significant statistical variation and 
the actual TV signal strengths in an area can vary from the predicted signal strengths by as much as 
20 to 30 dB due to shadowing, multipath fading and other propagation variables. The information 
submitted into the record thus far has not demonstrated how the prediction model could be made 
sufficiently reliable to ensure against harmful interference. Accordingly, we are not allowing the 
operation of fixed TVBDs on adjacent TV channels at this time. We recognize, however, as 
240 See DTV Receiver Study at pp. 5-9, 15-13. 
241 See Google ex parte presentation of October 27, 2008. 
242 See Motorola ex parte presentation of October 28, 2008. 

Federal Communications Commission FCC 08-260 
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indicated by Google and Motorola that the availability of adjacent channels may be critical for 
certain applications. Therefore, we will defer a final decision on allowing operation of fixed devices 
on adjacent channels and will keep the record open pending the development of additional 
information demonstrating that a reliable method can be developed to address the above concerns. 
179. Application of TV Protection Criteria  Table of Separation Distances. As discussed 
above, the Commission proposed in the Notice to require that the TV station service and protection 
criteria be used in conjunction with appropriate computational software, including use of the 
Commissions propagation curves and a television station engineering database, for determining whether 
a TV channel is vacant at a particular location. This approach would require calculation of the protected 
service contours for each co-channel and adjacent channel TV station analyzed at a given location and 
calculation of protection ranges from the TV band device to ensure that a TVBDs is far enough from the 
protected contours of co-channel and adjacent channel TV stations that the D/U ratios are met at locations 
within the contours of those stations. This is essentially the same approach that is used to ensure that low 
power TV stations do not cause interference to full service TV stations or to other low power TV stations. 
180. In evaluating that approach, we now note that the Commission has not previously 
specified D/U ratios in Part 15 of the rules to protect licensed services from interference by unlicensed 
devices. Rather, as in the case of Part 15 medical telemetry devices that operate in the TV bands and 
radio frequency identification devices that operate at 433 MHz, it has adopted the simpler approach of 
specifying minimum required separation distances between unlicensed devices and the services being 
protected.243 A table of minimum required separation distances between TV station contours and TV 
white spaces devices would similarly be easier to implement than D/U ratios and provide certainty as to 
whether a particular TV band device is far enough away from TV stations service areas to avoid causing 
interference. Accordingly, we are adopting this alternative approach for ensuring that fixed TV band 
devices do not cause interference to TV service. The table of separation distances we are specifying in 
the rules will provide protection that is functionally equivalent to that which would be provided under the 
D/U ratio approach. 
181. In developing the table of separation distances, we believe it is desirable to minimize 
complexity for compliance. In this regard, we have balanced this goal of simplicity with the need to 
provide assurance that TV services will be adequately protected. Given that the power of fixed TVBDs 
will be limited to 4 watts EIRP, the most important variable in determining the separation distance 
between a particular TVBD and a TV stations protected contour is the height of the devices antenna 
above ground. For example, using the FCC curves in Section 73.699 of the rules and the D/U protection 
ratios specified above, we find that a transmit antenna at a height of 30 meters transmitting with 4 watts 
EIRP could cause co-channel interference to a TV receiver with an antenna 10 meters above ground at a 
distance of 14.4 kilometers and adjacent channel interference at 0.74 kilometers. 244 For transmitting 
antennas at lesser heights, the FCC curves do not provide usable data, so the Okumura propagation model 
is applied.245 Using that same transmit antenna at less than 10 meters above ground, interference could be 
caused by a TVBD to a TV receiver at a distance of 8.0 kilometers to a co-channel TV station and 0.1 
kilometers to an adjacent channel TV receiver. A similar calculation applied to a TVBD antenna at 3 
meters above ground level calculates that interference can be avoided if separation distances of 6.0 
kilometers and 0.1 kilometers are maintained for co and adjacent channel TV stations, respectively. As 
243 See 47 C.F.R.  15.240 and 15.242. 
244 See 47 C.F.R.  73.699. 
245 See Okumura, Y., et. al., Field Strength and its Variability in VHF and UHF Land-Mobile Radio Service, 
Review of the Electrical Communication Laboratory, Vol. 16, Nos. 9-10, 1968.

Federal Communications Commission FCC 08-260 
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discussed below, we are limiting the maximum antenna height of fixed unlicensed TVBDs to 30 meters 
above ground level and find that this will appropriately balance the needs of unlicensed fixed TVBDs to 
achieve adequate service range while minimizing the range at which those operations could impact 
licensed services. We will use these distances in our rules as shown in Table 3:246 
Table 3 
Minimum Required Separation Distances between Fixed Unlicensed TV Band Devices 
and TV Service Contour Edges 
Antenna Height of 
Unlicensed Device 
Required Separation (kilometers) 
From Digital or Analog TV (Full Service or Low 
Power) Protected Contour 
Co-channel Adjacent Channel 
Less than 3 meters 6.0 km 0.1 km 
3  Less than 10 meters 8.0 km 0.1 km 
10  30 meters 14.4 km 0.74 km 
182. Protection of translator receive sites and cable headends. TV translator receive sites are 
often located on high towers or at high elevations and use high gain antennas to receive a full service 
stations signal well beyond the stations service area.247 Cable headends are facilities that acquire and 
distribute video service signals over a cable television system. Broadcast TV signals are often received 
off-the-air at a cable headend for retransmission over the cable system. In many cases, the cable headend 
will use an antenna with high gain mounted high up on a tower to receive a TV stations signals well 
beyond the stations service area in a manner similar to that used by TV translators. 
183. TV translator operators express concern that their receive sites are often outside of the 
service contour of the full service stations they re-transmit and request that those sites be protected no 
matter where they are located.248 The National Translator Association (NTA) recommends protecting 
translator reception in a keyhole shaped area in front of the translator receive site on a line to the station 
being received. It suggests that the Commission protect reception over a 60 degree arc to a distance of 
80 kilometers for co-channel reception, and 20 kilometers for adjacent channel reception.249 
184. Cable operators similarly request that cable headends be protected from interference from 
unlicensed devices, even where the headends are located outside the protected contours of the stations 
being received for transmission over a cable system, in order to ensure that cable systems will continue to 
be able to deliver broadcast TV signals to their subscribers.250 
246 In specifying the distances in Table 3, we assume that the TVBD antenna is located in an area where it is not 
situated significantly above the average terrain elevation. While there could be some increased potential for 
interference from a device that is located on high terrain, we believe that such installations will be infrequent. In 
addition, our registration requirement will make it possible to identify and rectify any interference that might arise 
from locating a device on high terrain. 
247 A TV translator receive site is a facility at which a translator receives the full service station signal it retransmits 
(note that it is not one of the individual viewer locations that receive a translators signal). 
248 See National Translator Association Notice comments at 6. 
249 See National Translator Association Further Notice comments at 4. 
250 See NCTA Further Notice comments at 15.

Federal Communications Commission FCC 08-260 
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185. Discussion. We find that is important to avoid disruption of TV service to viewers who 
are located beyond TV station service areas and able to receive those signals through retransmission on 
TV translators (as well as low power TV and Class A TV stations; collectively we will refer to these as 
TV translators herein) and cable systems. While those viewers are in fact located beyond the areas where 
we normally protect TV services, in these cases TV services have de facto been extended and valuable 
service is being provided to a significant number of households. If a TV band device were to be located 
between the TV translator/cable headend and station and then operate on one or more of the channels 
being received by those facilities in a manner that results in interference, TV reception to the households 
the cable system services could be disrupted. We therefore will protect TV translator receive sites and 
cable headends. 
186. We will protect TV translator receive sites and cable headends using the criteria 
recommended by the NTA.251 Specifically, to prevent interference within the main reception beam of the 
TV translator station or cable headend receive antenna, operation of TV band devices will be prohibited 
co-channel and adjacent channel to the channel(s) being received by these facilities over an arc of +/- 
30 degrees from a line between the receive site and the TV station(s) being received. The protected zone 
will extend to the edge of the TV station protected contour, and will be limited in distance to 
80 kilometers from the protected contour for co-channel operation and to 20 kilometers from the 
protected contour for adjacent channel operation. We believe that there are very few cases where a 
translator receive site or cable headend could be farther outside a TV station protected contour than 
80 kilometers and still receive a usable signal. 
187. In addition, to prevent interference to TV translators and cable headends from unlicensed 
TV band devices outside the main beam of the cable TV or translator receive antenna, we will prohibit 
TVBDs from operating co-channel to the channel(s) being received by these facilities within 8 kilometers 
and from operating adjacent channel within 2 kilometers in all directions off the +/- 30 degree arc. Again 
this protection will be afforded only to TV translators and cable headends located within 80 kilometers of 
a TV stations service area. These protections will be afforded to TV translators and cable headends that 
register their location and the channel(s) they receive with the unlicensed TVBD database. Parties that 
operate such facilities and that want to take advantage of these protection criteria will be responsible for 
requesting the database administrator to register their receive site locations and received TV station 
channels in the database; facilities not registered will not be protected. To prevent unnecessary entries 
into the database, we will only permit translator receive sites and cable headends to be registered if they 
are outside the protected contour of the TV station being received. 
188. Protection of fixed Broadcast Auxiliary Services (BAS) links. TV studio transmitter links 
(STLs), TV relay stations and TV translator relay stations may be authorized to operate fixed point-topoint 
service on UHF TV channels 14-69 on a secondary basis.252 The maximum EIRP for these services 
is 35 dBW (3,162 watts), although the Commission can authorize higher power if the license application 
is accompanied by an engineering analysis demonstrating why this limit needs to be exceeded.253 
251 The record does not address specific protection standards for cable headends. However, given that the receive 
circumstances for TV translators and cable headends located outside TV services are essentially the same, we 
believe that the same protection measures are appropriate for both. 
252 See 47 C.F.R. 74.602(h). A TV STL station is a fixed station used for the transmission of TV program material 
and related communications from the studio to the transmitter of a TV broadcast, Class A TV or low power TV 
station. A TV relay station is a fixed station used for transmission of TV program material and related 
communications for use by TV broadcast, Class A TV and low power TV stations. A TV translator relay station is a 
fixed station used for relaying programs and signals of TV broadcast or Class A TV stations to Class A TV, low 
power TV and TV translator stations. See 47 C.F.R.  74.601. 
253 See 47 C.F.R. 74.602(h)(1). 

Federal Communications Commission FCC 08-260 
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Transmissions are one-way from a transmitter to a receiver, and a system can have more than one link. 
Except for the temporary links addressed by SBE in its comments, the Commissions Universal Licensing 
System (ULS) contains information on BAS fixed links, including the frequency and the geographic 
coordinates of both the transmitter and receiver.254 The ULS shows approximately 220 authorized fixed 
broadcast auxiliary links in channels 14-51 that are in active status. These links typically range in 
distance from a few kilometers to tens of kilometers, although the Commission has authorized links to 
operate over distances in excess of 100 kilometers. The Commission did not propose specific protection 
criteria for this these BAS links in either the Notice or First R&O/Further Notice, and no parties 
suggested criteria in their comments. However, because it is a licensed service it must receive protection 
from unlicensed TV band devices. 
189. We find that the most appropriate way to protect fixed BAS links is to specify an 
exclusion zone near the receive sites similar to the zone we are allowing for translator receive sites and 
for cable headends located outside the protected service contour of a TV station. Specifically, we will not 
allow TV band devices to operate co-channel or adjacent channel to a fixed BAS link receiver within 
+/- 30 degrees of the line extending from the BAS transmitter to the receiver. The protection zone for 
BAS links will similarly extend to a maximum distance of 80 kilometers from the receiver toward the 
transmitter for co-channel operations and to 20 kilometers from the receiver toward the transmitter for 
adjacent channel operation. In addition, to prevent interference from TV band signals outside the main 
beam of the BAS receive antenna, we will prohibit co-channel operation of TV band devices within 
8 kilometers and adjacent channel operation within 2 kilometers of BAS receive sites in all directions off 
the +/- 30 degree arc. These restrictions will be applied via the TV bands database; that is, the database 
will be required to include records for BAS links and their technical information and to calculate the 
exclusion areas where unlicensed TV band devices are not allowed to operate. Permanent fixed BAS 
receiver sites are already recorded in the Commissions database, so the licensees of those sites will not 
need to take any action because the designated database administrator(s) will be responsible for obtaining 
and entering that information from our database. However, we note SBEs concern that temporary fixed 
BAS links and those operating under STAs are not in the database. We will therefore allow parties 
operating such links the option of registering those facilities with the database if they so desire to obtain 
the same protection as permanent fixed BAS links. 
190. Protection of PLMRS/CMRS services. As discussed above, the PLMRS/CMRS operates 
on one or two channels in the range of 14-20 in 13 metropolitan areas and the communications systems on 
these channels are principally used in support of public safety operations. In addition, a number of 
PLMRS/CMRS operations have been authorized under waivers at locations beyond the 130 kilometer 
protection zones around the 13 metropolitan areas where they are permitted to operate.255 In the Notice, 
the Commission proposed to require TV band devices to protect PLMRS/CMRS operations using the 
same criteria in Part 74 of the rules that are applied to TV translator, low power TV and Class A TV 
stations.256 That is, it proposed to require TVBDs to protect PLMRS/CMRS operations within a 130 
kilometer radius of the designated geographic coordinates for each of the 13 metropolitan areas. The field 
strength from a TV band device on a co- or adjacent channel would not be permitted to exceed 52 dBV 
or 76 dBV, respectively, at the 130 km protected radius of the PLMRS/CMRS metropolitan area. Based 
on these field strength criteria, the Commission proposed to specify that a co-channel TV band device 
254 See SBE Notice comments at 3-4. 
255 See Notice at  35-36. The areas where PLMRS/CMRS operations are permitted on a waiver basis are 
identified on the Commissions Universal Licensing System Database at 
http://wireless2.fcc.gov/UlsApp/UlsSearch/searchLicense.jsp 
256 See Notice at ; see also 47 C.F.R.  74.709.

Federal Communications Commission FCC 08-260 
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would have to be 4 kilometers or farther outside this protected radius and an adjacent channel TV band 
device would have to be 1 kilometer or farther outside this protected radius.257 
191. Microsoft states that, given the low duty cycle nature and comparatively low power levels 
likely for unlicensed services in the TV bands compared to the often 100% duty cycle of low power TV 
stations, the Commissions proposals for protecting the PLMRS/CMRS seem unduly conservative and 
constraining.258 Microsoft does not, however, recommend any alternative protection criteria. Motorola 
argues that TV band devices should operate no closer than 15 kilometers outside the 130 kilometer 
protected radius, rather than 4 kilometers as proposed by the Commission.259 Motorola derives this 
separation distance from an analysis in which it believes that the Commission should 1) define a power 
spectral density limit of 8 dBm/3 kHz consistent with Part 15 rules, 2) consider antenna height and terrain 
variation, and 3) define an interference level to PLMRS/CMRS of 21 dBmV/25 kHz. 
192. We are adopting the proposed protection criteria and therefore will require that cochannel 
TV band devices be located at least 4 kilometers outside the PLMRS/CMRS protection radius of 
the 13 metropolitan markets and that adjacent channel TV band devices be located at least 1 kilometer 
outside this protection radius. These values were derived using the same criteria used to protect 
PLMRS/CMRS operations from low power TV stations, and no party has demonstrated that they would 
provide inadequate protection.260 Therefore, we decline to adopt a different definition of interference to 
the PLMRS/CMRS or adopt additional protection requirements (i.e., a power spectral density limit) for 
TV band devices as requested by Motorola. We note that the criteria in Part 74 of the rules were 
developed for protecting PLMRS/CMRS operations against interference from analog TV signals, which 
have a very non-uniform power spectral density due to the high percentage of power concentrated near 
the video carrier. Because the current rules adequately protect the PLMRS/CMRS with no power spectral 
density limit, there is no need to specify a power spectral density limit for TV band devices, which we 
expect will generally have a much more uniform power spectral density than analog TV. 
193. In the case of PLMRS/CMRS operations that have been authorized under waivers at 
locations beyond the 130 kilometer protection zones around the 13 metropolitan areas, we note that the 
boundaries of those areas are based on a geographic area (generally that of a county government area) 
rather than being defined by a point radius. In those cases, mobile units do not operate beyond the 
geographic boundary of the waiver area. However, the Commissions Universal Licensing System (ULS) 
contains the coordinates of the licensed PLMRS/CMRS base stations rather than the geographic 
boundaries of the area covered by the waiver. Therefore, the most practical way to provide protection to 
PLMRS/CMRS operations pursuant to waivers is to provide a protected zone around each base station 
licensed under the waiver. The rules specify that the maximum distance a PLMRS/CMRS base station 
may operate from the geographic center coordinates in the 13 metro areas is 80 kilometers, and then 
provide an additional 50 kilometer zone of protection for those stations from low power TV operations.261 
257 See Id. 
258 See Microsoft Notice comments at 21. 
259 See Motorola Further Notice comments at 12. 
260 Specifically, these values are the distances to the 52 dBu and 76 dBu contours, which were calculated by our 
staff using the FCC F(50,10) curves in Section 73.699 of the rules with an effective radiated power of 4 watts EIRP 
and an antenna height of 30.5 meters. 
261 The transmitter sites of PLRMS/CMRS base stations must be located not more than 80 kilometers from the 
geographic center coordinates of the 13 metropolitan areas, and mobile units must be operated within 48 kilometers 
of their associated base station. See 47 C.F.R.  90.305. Low power TV stations must protect PLMRS/CMRS 
operations to 130 kilometers from the geographic center coordinates of the 13 metro areas. Thus, low power TV 
(continued.)

Federal Communications Commission FCC 08-260 
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Thus, new/relocated low power TV stations must not be located within 130 km of a co-channel 
PLMRS/CMRS base station. We will protect PLMRS/CMRS operations under waivers at the same 50 
kilometer distance from base stations as in the 13 metro areas. As discussed above, to prevent 
interference within a PLMRS/CMRS protected zone, co-channel and adjacent channel TVBDs must be 
located at least 4 kilometers and 1 kilometer outside the protected zone, respectively. Thus, we will 
specify that co-channel unlicensed TVBD devices may operate no closer than 54 kilometers from a base 
station operating under a waiver, and that adjacent channel unlicensed TVBDs may operate no closer than 
51 kilometers from a base station operating under a waiver. 
194. Offshore Radiotelephone Service. The Offshore Radiotelephone Service is a primary 
radio service that operates on TV channels 15-17 in designated areas along and within the Gulf of 
Mexico.262 This service is intended to provide public message service between offshore subscribers and 
central stations. It is used principally for communications between workers at offshore oil facilities and 
stations on the coast. Operation of low power TV stations is prohibited within designated geographic 
areas along the Gulf coast on channels 15-18 to prevent interference to the Offshore Radiotelephone 
Service.263 The Commission did not specifically propose protection criteria for the Offshore 
Radiotelephone Service in either the Notice or First R&O/Further Notice, and no parties addressed this 
issue in comments. However, it is a licensed service and therefore must be protected from interference 
from unlicensed TV band devices. We believe it is reasonable to protect Offshore Radiotelephone 
Service from unlicensed TVBDs in the same manner as we protect those operations from low power TV 
stations. Accordingly, are prohibiting unlicensed devices, both fixed and personal/portable from 
operating on channels 15-18 within the designated geographic areas that low power TV stations must 
avoid to protect the Offshore Radiotelephone Service. This will be accomplished through the use of the 
geo-location and database capabilities. 
195. Protection of wireless microphones and other Part 74 devices. Low power auxiliary 
stations, which include wireless microphones, cue and control communications systems and camera 
synchronization devices, are allowed to operate on vacant TV channels with power levels of 50 mW in 
the VHF bands and 250 mW in the UHF bands on a secondary basis under Part 74 of the rules.264 
Wireless assist video devices (WAVDs) are similarly allowed to operate under Part 74 on channels 8-12 
and 14-51, excluding channel 37, with a power level of 250 mW.265 Operations in these services are 
licensed, so unlicensed TV band devices are required to provide interference protection to them. The 
licenses for low power auxiliary and WAVD devices can specify multiple operating channels, but do not 
specify the exact geographic coordinates where the devices can operate. Further, these devices operate 
intermittently, rather than continuously like TV stations 
196. As indicated above, wireless microphone manufacturers and users request that we protect 
these devices through several measures, including: 1) limiting new low power devices to fixed operation, 
2) prohibiting new low power devices from operating on channels adjacent to occupied TV channels 
and/or reserving six vacant TV channels in each market to ensure that there is spectrum available for 
wireless microphones, 3) requiring new low power devices to incorporate spectrum sensing to detect 
(Continued from previous page) 
stations must protect PLMRS/CMRS operations to 50 kilometers from the nearest base station. See 47 C.F.R. 
74.709(b). 
262 See 47 C.F.R.  22.1001, et seq. 
263 See 47 C.F.R.  74.709. 
264 See 47 C.F.R.  74.861(e). 
265 See 47 C.F.R.  74.870.

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wireless microphones, and 4) requiring new low power devices to sense for the presence of a smart 
beacon that would operate when wireless microphones are in use in an area. 
197. We recognize that protection of low power auxiliary devices and WAVDs involves 
somewhat different considerations than fixed services that continuously, or nearly continuously, occupy 
the same channels/frequencies or area wide mobile services. The nature of these devices and their use is 
such they operate for relatively short periods of time at various times (albeit sometimes on a frequent and 
scheduled) basis and the specific frequencies they use for operation often change from time to time, even 
at locations such as major event venues. As a result, there are no existing databases that can identify 
which TV channels are in use by wireless microphones and WAVDs at a given location and a spectrum 
sensing feature that would be able to reliably detect active microphone operation would not be effective at 
times when the microphones are not operating. 
198. We believe that wireless microphones can be adequately protected under an approach that 
provides for registration of sites and times where microphones are operated and also includes spectrum 
sensing as a back-up to the registration system. Under the plan we are adopting, wireless microphone 
licensees will be allowed to register the sites where they operate along with the days and times when they 
operate. The database system will then prohibit operation of unlicensed TVBDs from operating near that 
site on the channels and at the times used for wireless microphones. Wireless microphone licensees will 
be allowed to register sites and times on a permanent or temporary basis. In addition, as indicated above, 
TVBDs will be required to look for and detect wireless microphones at signal levels as low as -114 
dBm/6 MHz. This will provide protection for microphones that operate on channels on which unlicensed 
TVBDs are also allowed to operate.266 We are not requiring that unlicensed TVBDs be able to receive 
and respond to a smart beacon signal identifying the presence of wireless microphone signals for the 
reasons discussed above. 
199. The protection of wireless microphone registered sites will be limited to facilities with 
wireless microphone use at well defined times and locations.267 Unlicensed TV band devices will be 
required to include the channels used by wireless microphones and other low power auxiliary devices at 
such venues in their determinations of available channels for operation. Event site registrations will 
indicate the type of event, the TV channels used, the geographic coordinates of the event site, whether use 
of channels at the site is on an on-going permanent basis, the days and times when the site operates, or if 
site operates on an occasional basis, the dates of such operation. Registration of temporary sites will also 
be permitted. Unlicensed TVBDs will not be allowed to operate within one kilometer of the recorded 
geographic coordinates of registered event venues on the channels specified as in use by the registrant 
during the designated times when low power auxiliary devices are used. This separation distance 
recognizes the fact that wireless microphones and other devices used at an event site will be at relatively 
strong signal levels compared to unlicensed TVBD signals at that distance and also allows for wireless 
microphone use around the area occupied by large event venues such as stadiums, fairgrounds etc. In the 
case of very large venues such as race tracks and other event sites that may occupy more than a 
significant portion of the area within a one kilometer geographic square, the operator/coordinator/licensee 
will be allowed to submit multiple registrations to specify the coordinates of more than one point in the 
facility. As discussed further in the section on the TV bands database, the Commission reserves the right 
to request that the database administrator remove voluntarily submitted data that is inaccurate or not 
justifiable, e.g., is filed for the purpose of limiting other parties legitimate use of the white spaces rather 
than protecting authorized services. In addition to these protections, the TVBD channel usage plan and 
266 The technical standards for this sensing requirement are discussed in the technical requirements section below. 
267 Significant wireless microphone use includes instances where one or more microphones are in operation for a 
period of time not less than one hour and can include single events at a site. 

Federal Communications Commission FCC 08-260 
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our decision to reserve two UHF channels in the range 21-36 and 38-51 will ensure that channels are 
available for itinerant microphone operations. 
200. We do not find it desirable to reserve channels for wireless microphone use in all 
markets. Such an approach would restrict the availability of spectrum for TVBDs and we see no reason 
to restrict TVBD operations on frequencies at locations and times where there are no microphone 
operations.268 In addition, wireless microphones will have access to those channels where TVBDs are not 
allowed to operate. While the channels where TVBDs are not allowed to operate may not be open in all 
markets, in many markets there will be channels on which wireless microphones may operate without the 
need for special measures to receive protection from TVBDs. 
E. TV Bands Database System Requirements 
201. As indicated above, all unlicensed fixed TV band devices and all personal/portable 
devices, except for those that operate in Mode I under control of a fixed or Mode II personal/portable 
device, will be required to access a TV bands database to obtain information on the available channels at 
their location and all unlicensed fixed TVBDs will be required to register their operations. In the Notice 
and the First R&O/Further Notice, the Commission made proposals and asked for comment on a number 
of specific provisions relating to this database system.269 In particular, the Commission requested 
comment on the information about authorized stations that should be in a database, such as geographic 
coordinates, type and class of station, transmit power level, antenna height and other antenna 
characteristics, the means by which an unlicensed device would access the database, and how often the 
database would need to be updated. In this section we address the specific plan for operation of the 
database system, including the information to be stored in the database, the requirements that apply to 
unlicensed TVBDs for accessing the database system, the responsibilities of a database administrator, and 
database administrator selection. 
202. In comments responding to the Notice, Entravision Holdings, LLC (Entravision) and 
NTA state that a device that automatically checks a database should do so continuously, and that a 
maintenance routine that allows a frequent check of the accurate functioning of the automatic facilities 
should be approved with the equipment certification.270 Itron suggests that we require unlicensed TVBDs 
to automatically check the database daily or weekly.271 However, Josephson Engineering, Inc. states that 
monthly or bimonthly database checks should be sufficient because there is a significant delay between 
the issuance of a TV station construction permit and actual occupancy of a frequency.272 
203. Motorola submits that the database system could be managed by a third party. It further 
states that channel availability information should be in a standard format and updated regularly through 
authorized database registration and that third party providers of database information e.g., a frequency 
coordinator, industry association, or local broadcast group, should be responsible for its accuracy.273 
Harris similarly believes that the database should be updated at least weekly and states that a device 
268 As discussed above, we are, however, reserving two channels in the UHF range for low power auxiliary/wireless 
microphones in those markets where one or more channels in the range 14-20 are used for PLMRS/CMRS 
operations. 
269 See Notice at  26-28 and First R&O/Further Notice at  50-51. 
270 See Entravision Notice comments at 5, NCTA Notice comments at 3. 
271 See Itron Further Notice comments at 5-6. 
272 See Josephson Notice comments at 2. 
273 See Motorola Notice comments at 10.

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should shut down if it does not receive database updates.274 Motorola submits that the database should 
contain the Commissions officially established service contour levels to make sure that consistent 
calculations are performed by various manufacturers equipment.275 It states that the information in the 
database should include the TV transmitter location, ERP, antenna height above average terrain (HAAT), 
radiation center above ground level (RCAGL), FCC service code, license status, and call sign. In 
addition, Motorola believes that the database should be flexible enough to include different protection 
levels depending on the transmit power of the TV band device since the interference potential of TV band 
devices will vary with transmitted power. Motorola supports the Commissions suggestion that a private 
party be selected to develop and maintain the database. 276 CBA suggests that the funding of the database 
could come from a one-time fee assessed at the purchase of white space devices.277 
204. Database system plan and operation: We are adopting a database plan that will provide 
for efficient and effective management of licensee and TVBD records and the identification of available 
channels for TVBDs. As an initial matter, we will consider authorizing more than one entity to operate a 
TV bands database. Thus, depending on expressed interest to a solicitation for database managers, the 
Commission could select multiple database administrators that could offer services on a competitive 
basis. In this regard, we are mindful that sufficient safeguards must be put in place to ensure that TVBD 
users would receive the same set of available channels regardless of which database it queries such that 
entities compete solely on the basis of cost and speed and efficiency of service. The database(s) will be a 
privately owned and operated service that unlicensed TV band devices must contact to obtain information 
on channel availability at the locations where they are operated and, in the case of fixed devices, to 
register their operation at those locations. We will permit database administrators to charge fees for 
registration of fixed devices and the provision of lists of available channels to fixed devices and 
personal/portable devices. We believe that third parties will be in the best position to develop and 
manage a database in a fair and equitable manner and to address the day-to-day operational demands. 
Any TV bands database will be required to contain information on: 1) all of the authorized services that 
operate in the TV bands using fixed transmitters with designated service areas, including full service and 
low power TV stations, 2) the service paths of broadcast auxiliary point-to-point facilities, 3) the 
geographic regions served by PLMRS/CMRS operations on channels 14-20, 4) regions served by the 
Offshore Radiotelephone Service, and 5) the locations of cable headends and low power TV receive sites 
that are outside the protected contours of the TV stations whose signals they receive. In addition, a TV 
bands database will be required to contain the locations of registered sites where wireless microphones 
and other low power auxiliary devices are used on a regular or scheduled basis. A TV bands database 
will be required to register unlicensed TV band devices in accordance with the rules and to provide such 
devices with a list of the available channels at the specific locations where they are operating. 
205. Unlicensed TV band devices, except for those operating as a client to a either a fixed 
device or a personal/portable device operating in Mode II, will be required to contact a TV bands database 
through the Internet to obtain a list of available channels at their location in accordance with the rules set 
forth herein. Database administrator(s) will define protocols so that TV band devices can access a 
database automatically without human intervention. A TV bands database will calculate the television 
channels that are available for use by unlicensed TV band devices at their individual locations based on 
the information in the database and consistent with the separation distances set forth in the rules and then 
274 See Harris Notice comments at 8. 
275 See Motorola Further Notice comments at 20. 
276 Id. 
277 See CBA Further Notice comments at 4.

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return a list of those channels to the TV band device on an approximately real-time basis. A device may 
then transmit only on those channels which the database indicates are available for its use.278 The 
database system will also record registration information from each fixed TV band device. The 
registration information will include the devices location (geographic coordinates) and contact 
information for its user/operator. This registration information will assist TV band device users in 
coordinating efficient use of the available television channels at a particular location. In addition, should 
any interference to licensed services occur, the registration information will assist in the identification of 
the source of any such interference. Finally, a TV bands database will include provisions for sharing 
registration data with any other Commission authorized TV bands database. 
206. In considering a minimum interval for re-contacting the database system, it is important 
to note that protection is afforded not only to TV and other fixed facilities that do not change often, but 
also to mobile/portable facilities such as wireless microphones. As already described, we will allow 
venues where wireless microphones and other low power auxiliary devices are used on a regular or 
scheduled basis to register such usage in the TV bands database. Because such usage could change on a 
daily basis, we will require fixed and mode II TVBDs to recheck the database, at a minimum, on a daily 
basis. Rechecking in this manner will also provide for timely protection of new or modified licensed 
facilities. This approach accounts for the continual changes that will occur over time as new licenses are 
issued or inaccuracies are corrected. We believe that because database access will be done automatically 
over the internet, rechecking the available channels will not be burdensome. If a device fails to contact a 
TV bands database on any given day, it will be required to cease transmitting after a one-day grace 
period. That is, it must cease operating at 11:59 PM on the day following a day when it does not contact 
a TV bands database. This grace period will allow for situations where there has been a sustained power 
loss, an internet outage, or other circumstances that disrupt a devices ability to contact a TV bands 
database. In accessing a TV bands database to update its list of available channels, a device will only 
need to provide its identification information, current location and, for fixed devices, any changes in its 
registration information. 
207. In addition to the daily database update requirement, personal/portable devices operating 
in Mode II will be required to re-establish their location coordinates and to access a TV bands database 
for a list of available channels each time they are activated, i.e., powered on, or move. If such a device 
maintains a powered on state for one-day or more, the device will then be required to re-check a TV 
bands database as described above. We find that these measures will ensure that both fixed and 
personal/portable devices properly maintain a current list of available channels. 
208. Database information. To ensure that a TV bands database contains sufficient elements 
to both determine available TV channels for a given location and to register fixed TVBDs, we must define 
the set of data elements for the database. The elements for the various types of systems that will be in the 
database is described below. Additionally, we note that for all coordinates we will require that they be 
referenced to the North American Datum of 1983 (NAD 83) and as described above, we will require 
accuracy to within 50 meters. 
209. The information collected from fixed unlicensed TV band devices will include: 
(1) FCC Identifier (FCC ID) of the device279 
278 We will require that fixed TV band devices be designed such that consumers and installers cannot override the 
functionality of the device to access a database to obtain a list of available television channels and transmit only on 
those channels contained in the list. 
279 See 47 C.F.R.  2.926.

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(2) manufacturers serial number of the device 
(3) devices coordinates (latitude and longitude) 
(4) name of the individual or business that owns the device 
(5) name of a contact person responsible for the devices operation 
(6) address of the contact person 
(7) email address of the contact person 
(8) phone number of the contact person. 
210. The information collected from personal/portable unlicensed TV band devices, which 
will not be registered and only access the database for available channels, will include: 
(1) FCC Identifier (FCC ID) of the device 
(2) manufacturers serial number of the device 
(3) devices coordinates (latitude and longitude) 
211. The FCC ID and serial number of the TV band device will uniquely identify individual 
fixed unlicensed TV band devices. This information will assist the Commission if compliance issues 
concerning devices arise. A fixed TV band device will be required to update any information that has 
changed when it makes its daily check with a TV bands database to determine if the list of available 
channels at its location has changed. If a fixed device does not check the database for three months, its 
registration will be removed from the database. 
212. A database administrator will not be responsible for resolving claims of interference from 
TVBDs. If there is a claim of interference, a database administrator, upon request from the Commission, 
must provide TVBD identifying information. If a device is found to be causing interference, the 
Commission may then require that the party responsible for the unlicensed device take corrective actions 
or cease operating the device until the interference is resolved. In addition, if a representative of the 
Commission attempts and is unable to contact the person responsible for a device that is determined to be 
causing interference, the Commission may require the TV bands database to return a message of no 
channels available to the device at its next scheduled re-check. This will effectively shut down the 
device until contact is made with the responsible party so that the interference can be resolved. The 
database administrator will rescind a no channels available status for that device only upon 
authorization by the Commission. 
213. Now, regarding services that will be protected a TV bands database will contain the 
following information on full-power television stations, digital and analog Class A stations, low-power 
television stations (LPTV), television translator stations, and television booster stations: 
(1) transmitter coordinates (latitude and longitude) 
(2) effective radiated power (ERP) 
(3) height above average terrain of the transmitter (HAAT) 
(4) horizontal transmit antenna pattern (if the antenna is directional) 
(5) channel number 
(6) station call sign 
A TV bands database will also be required to include data on the distributed transmission system (DTS) 
facilities of stations using that technology and to use that data in determining the protected service areas 

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of such stations.280 The information for full service TV stations is available on the Media Bureaus 
Consolidated Data Base System (CDBS).281 
214. A TV bands database will also include information on Broadcast Auxiliary Service 
(BAS) facilities, which use vacant television channels for fixed point-to-point links. For permanent links, 
this information is available from the Commissions Universal Licensing System (ULS).282 For 
temporary BAS links, the party authorized to operate the link may voluntarily submit this information to a 
TV bands database. For each BAS link the TV bands database will contain: 
(1) transmitter coordinates (latitude and longitude) 
(2) receiver coordinates (latitude and longitude) 
(3) channel number 
(4) call sign 
215. In some geographic regions, certain television channels from channel 14through channel 
20 are set aside for use by PLMRS and CMRS operations. These regions are specified in the 
Commissions rules.283 A TV bands database will contain the center coordinates (latitude and longitude) 
for each of these regions and the television channels used in each region. For each of these regions, a TV 
bands database will include the following data elements: 
(1) region name 
(2) channel(s) reserved for use in the region 
(3) geographic center of the region (latitude and longitude) 
(4) call sign 
216. In addition, numerous PLMRS and CMRS licenses have been granted in these channels 
outside of the identified geographic regions under waivers to the Commissions rules.284 These waiver 
licenses are specified in various ways such as, for example, by allowing a particular transmitted power 
and antenna height for a base station at a specified location or by specifying a geographic area of 
coverage, such as the boundaries of a local county administrative area. The database can be populated by 
information pertaining to facilities authorized by the Commission via an extract from the Wireless 
Telecommunication Bureaus ULS database. This database contains information on license holders, 
280 See Digital Television Distributed Transmission System Technologies, Report and Order, MB Docket No. 05- 
312, adopted November 3, 2008, FCC 08-256, released November 7, 2008. DTS involves the operation of multiple 
transmitters on the same channel to provide coverage of viewers within a TV stations authorized service area. 
281 The CDBS is available at http://www.fcc.gov/mb/cdbs.html. 
282 The ULS database is available at http://wireless.fcc.gov/uls/index.htm?job=home. 
283 The 13 regions where channels are set aside for PLMRS/CMRS operations are identified in Section 90.303 of the 
rules, 47 C.F.R.  90.303. Base stations may be located within 80 km. (50 mi.) of the center of the geographic 
region and mobile stations may be located within 48 km. (30 mi.) of the base stations. 47 C.F.R.  90.305. 
Consequently, mobile stations may be located within 128 km. (80 mi.) of the center coordinates of the geographic 
region. 
284 Some of these licenses have been issued under explicit waivers to our rules. Others have been issued without a 
formal waiver request and grant (in effect an informal waiver). For simplicity, we shall refer to all of these 
PLMRS/CMRS licenses outside of the geographic regions specified in 47 C.F.R. 90.303(b) as having been granted 
under a waiver to our rules since they do not technically comply with our rules.

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facility operation parameters (frequency, location, etc.), and any special conditions that apply. For each 
of these waiver licenses the following information will be placed into a TV bands database: 
(1) transmitter location (latitude and longitude) or geographic area of operations 
(2) effective radiated power 
(3) transmitter height above average terrain (if specified) 
(4) antenna height above ground level (if specified) 
(5) call sign 
In cases where the operator of a PLMRS/CMRS system licensed under a waiver operates multiple 
transmitters (not including systems that are licensed to operate in a coverage area), information on each 
transmitter will be required to be maintained in a TV bands database. 
217. The Offshore Radiotelephone Service uses channels 15-18 along the coast of the Gulf of 
Mexico.285 The Commissions rules designate four regions to protect this service.286 For each of the four 
regions a TV bands database will contain the following information: 
(1) geographic boundaries of the region (latitude and longitude for each point defining 
the boundary of the region 
(2) channel(s) used by the service in that region 
218. As noted above, cable television systems often use antennas at their headends to receive 
broadcast television signals and then retransmit those signals to subscriber households throughout the 
cable system. In many cases, cable systems are able to receive broadcast TV signals at locations outside a 
stations protected service contour by using high gain antennas mounted on top of buildings or tall towers. 
Records identifying cable systems that receive TV stations outside of their service areas are not currently 
maintained in the Commissions databases. As indicated above, we are extending protection to the 
reception of TV signals by such cable headends. We are therefore allowing cable operators to register, 
with a TV bands database, their headends that receive TV signals outside of a stations protected contour 
and requiring that a TV bands database afford protection to those facilities in accordance with the 
provisions indicated above. A TV bands database will collect the following information to register a 
cable headend: 
(1) name and address of cable company 
(2) location of the headend receiver (latitude and longitude) 
(3) channel number of each television channel received, subject to the following 
condition: channels for which the cable headend is located within the protected 
contour of that channels transmitting station are not eligible for registration in the 
database 
(4) call sign of each television channel received and eligible for registration. 
(5) location (latitude and longitude) of the transmitter of each television channel received 
219. Television translator and low power stations, including Class A TV stations, rebroadcast 
the signal of a full service station or another low power station. Like many cable headends, TV 
translators/low power stations often receive the signal of the station they retransmit outside the 
285 See 47 C.F.R.  22.1007. 
286 See 47 C.F.R.  74.709(e). This rule defines four regions in which low-power television stations cannot operate. 
TV band devices will be excluded from these same four areas to protect the Offshore Radiotelephone Service.

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retransmitted stations protected contour.287 The TV translators and low power stations that currently 
receive the signal they retransmit off-the-air at locations beyond the originating stations protected service 
contour are not currently recorded in the Commissions databases. To protect the reception of signals at 
the receive sites of these stations, we will allow the licensees of such translators and low power stations to 
register their receive sites with a TV bands database and require the database to afford those sites 
protection in the same manner as similarly situated cable headends. A TV bands database will collect the 
following information to register a translator/low power receive site: 
(1) call sign of the TV translator or low power TV station 
(2) location of the TV translator or low power station receive site (latitude and longitude) 
(3) channel number of the retransmitted television station, subject to the following 
condition: a channel for which the television translator receive site is located within 
the protected contour of that channels transmitting station is not eligible for 
registration in the database 
(4) call sign of the retransmitted television station 
(5) location (latitude and longitude) of the transmitter of the retransmitted television 
station 
220. As discussed above, low power auxiliary stations such as wireless microphones and 
wireless assist video devices operate in the television bands on a secondary basis under Part 74 of the 
Commissions rules.288 These devices are usually licensed to operate over a broad geographic area and a 
wide range of television channels. The use of these devices is sometimes sporadic and nomadic and 
registration of the locations of such operations locations in a TV bands database would not be practical. 
However, in many cases wireless microphones and wireless assist video devices are used regularly and 
predictably, such as at major sporting events facilities, movie studio lots, and television studios. For these 
situations, the low power auxiliary device users will be allowed to register in a TV bands database, the 
location where the devices are used to aid in avoiding interference from TV band devices. In the case of 
large event facilities such as race tracks and golf courses, we will allow multiple registrations with 
different geographic coordinates to enable protection of the entire site. We will require that requests for 
registration of low power auxiliary devices that operate on a seasonal basis, only on certain days within a 
week or only at specific times include such information; TVBDs will be restricted from operation in the 
channels used at registered sites only on days and at times when low power auxiliary devices at the sites 
are in operation. Low power auxiliary registrations will be valid for no longer than a year, after which 
they may be renewed. The database will collect the following information on registered sites that use low 
power auxiliary devices : 
(1) name of the individual or business that owns the low power auxiliary device(s) 
(2) the name of a contact person 
(3) an address for the contact person 
(4) an email address for the contact person (optional) 
(5) a phone number for the contact person (optional) 
(6) coordinates where the device(s) are used (latitude and longitude) 
287 Many TV translators receive the signal they retransmit without needing to receive the retransmitted stations 
signal over-the-air. For example, they may obtain the signal of the station they retransmit through use a fixed pointto-
point microwave link or wireline connection. Other translators may receive the signal they retransmit via a 
receiver located within the retransmitted stations protected contour. In those cases, the translator receive sites need 
not be listed in a TV bands database. 
288 47 C.F.R.  74.801-82.

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(7) channels used by the low power auxiliary devices operated at the site 
(8) specific months, days and times when the device(s) are used. 
221. Database Administration. The Commission does not maintain a database of all TV and 
other stations and operations in the TV bands that could be accessed regularly in real-time by a large 
number of TVBDs dispersed throughout the country. We will designate one or more database 
administrators from the private sector to create and operate a TV bands database or databases. We 
recognize the interests of Google and other TVBD proponents in ensuring that database services be made 
available on a fair and low cost (or no cost) basis and believe that providing for authorization of more 
than one party to operate a TV bands database will serve that purpose. The Commission will issue a 
Public Notice requesting proposals from entities desiring to administer a TV bands database. Any entity 
that ultimately administrators such a database must make its services available to all TV band device 
users on a non-discriminatory basis. In addition, to ensure stability for these new devices, we will require 
each database administrator to provide services for a five-year term, which, at the Commissions discretion, 
may be renewed. In the event that there is only a single a database administrator and that entity does not wish 
to continue at the end of its term, it will be required to transfer its database along with the IP address(es) and 
URL(s) used to access the database to another designated entity and would be allowed to charge a reasonable 
price for conveyance of that resource. 
222. If the Commission chooses multiple entities to administer TV bands databases, we must 
ensure that each database contains consistent information so that regardless of which database a TVBD 
queries, it receives the same list of available channels in an area. Because a TVBD will only be required 
to contact a single TV bands database, there is a need for the TV bands databases to share accurate and 
timely registration information so that each database has a timely view of the radio environment and can 
make the best channel recommendations possible. Therefore, we will require that each TV bands 
database, at a minimum on a daily basis, provide to each other TV bands database, all registration 
information it receives during the previous day. This data sharing requirement extends only to 
registrations of fixed devices and protected facilities that are not otherwise captured in Commission 
databases, including wireless microphone and wireless assist video device locations, cable headends, and 
TV translator/low power receive sites. The databases can obtain information on other services, such as 
full service TV, land mobile licenses, etc. directly from Commission databases. We believe that this 
sharing requirement is extremely important to the success of TVBDs as it decreases the burden on any 
one database and also foster cooperation between the various database administrators. Although we are 
requiring the TV bands databases to share information daily, we will leave the actual implementation 
details up to the database administrators. Once the specific entities are selected, they will need to agree 
on a specific protocol and data format requirement so that manufacturers can build standard devices that 
can work with any of the databases and each database can easily transmit and receive data from each 
other database. In addition, the database administrators may agree whether to share on a more frequent 
timeframe than daily. 
223. A TV bands database will obtain much of the information on licensed use of the television 
bands for populating the database from the existing Commission databases. The TV bands database will 
be required to synchronize itself with the existing Commission databases at least once a week so that the 
information in the TV bands database remains current. Entities operating facilities that are entitled to 
protection but that are not licensed by the Commission, e.g., cable headends and TV translator/low power 
TV station receivers, will register their facilities through a process established by the database 
administrators. We will allow the TV bands databases to charge fees necessary to support the creation and 
operation of the database. These fees may be imposed on the operators of the TV band devices in order to 
access the database and/or on the manufacturers of TV band devices, but not on users of the television bands 
who are not currently in the Commissions database and desire to be included in the database. We do not 
believe it is appropriate to charge operators of licensed service for protection of their operations from 

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unlicensed devices. We believe that competition among databases will serve to keep fees low and 
reasonable. However, if parties believe that the fees charged by a TV bands database are excessive, they may 
petition the Commission for relief. 
224. We recognize that there is potential for inaccurate information to be entered into the 
database, for omissions to occur, and for records to be present for licensed facilities that are no longer 
operating. Such inaccuracies could be introduced in several ways. For example, any errors that might 
inadvertently be present in a Commission database could be transferred to a TV bands database.289 In 
addition, the fact that we are permitting information on certain services in the TV bands to be voluntarily 
provided introduces another potential for error. Parties submitting such information could inadvertently 
provide inaccurate coordinates, channel or other information, and there is also the potential that a party could 
knowingly provide false information on channel use at a location. The database administrators will be 
expected to respond quickly to verify and/or correct data in the event that a party brings claims of 
inaccuracies in the database to its attention, including advising the Commission of any errors that may appear 
in the Commissions records. Further, the Commission reserves the right to request the removal of 
voluntarily submitted information from a TV bands database in the event that such information is determined 
to be inaccurate or not in compliance with the rules. 
F. Technical Requirements 
225. In this section, we describe the technical requirements that are applicable to unlicensed 
TV band devices, i.e., both fixed and personal/portable. There are two general categories of 
requirements. The first consists of transmission system characteristics that are similar to those required 
for most types of transmitters, including the transmitter power, antenna characteristics and out-of-band 
emission limits. The second category consists of specific standards and requirements for the procedures 
to be used to enable unlicensed TV band devices to use the TV white space without causing interference 
to TV and other authorized services. 
1. Transmit Antenna Height Limits 
226. As the transmit antenna height of a fixed unlicensed TV band device is increased, both 
the devices signal coverage and the distance at which it could cause interference to other RF operations 
in the TV bands services also increase. In the First R&O/Further Notice, the Commission sought 
comment on whether any requirements are necessary with respect to transmitter height, such as a limit on 
maximum antenna height or a requirement for reduced power when a higher antenna is used.290 We did 
not receive any comments specifically addressing this issue with respect to fixed devices. However, the 
White Space Coalition submits that height restrictions should not be imposed on personal/portable 
devices, arguing that such restrictions would be impossible to administer and are unnecessary given the 
low power of the devices.291 
227. Our analysis indicates that the height of a TV band devices transmit antenna can 
significantly affect the distance at which interference could occur to licensed services in the TV bands. 
For example, as indicated above, a transmit antenna at 10 meters with 4 watts EIRP could cause 
interference to a TV receiver with a 9 meter antenna at a distance of 9 kilometers, while that same 
transmit antenna at 30 meters could cause interference to that TV receiver at a distance of 18 kilometers 
289 While we make every effort to ensure that our databases are complete and accurate, sometimes errors do occur; 
we correct any such errors as we become of aware of them and will continue to do so. 
290 See Further Notice at  44. 
291 See White Space Coalition Further Notice comments at 16.

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and at 100 meters could cause interference at 30.5 kilometers. We therefore conclude that in order to 
further limit the potential interference range of fixed unlicensed TVBDs it is necessary to limit the height 
of antennas used with those relatively higher powered devices. We are not imposing height restrictions 
on the lower powered personal/portable devices. 
228. In considering this issue, we observe that the distance that fixed unlicensed TVBDs must 
be separated from protected service areas is directly related to the maximum allowed antenna height, that 
is, the minimum required separation distance must increase as the maximum allowed antenna height 
increases. We believe that an antenna height limit of 30 meters will appropriately balance the needs of 
unlicensed fixed TVBDs for range to reach receivers while minimizing the range at which those 
operations could impact licensed services. 
229. We agree with the White Space Coalition that it is not practical to administer an antenna 
height limit for personal/portable devices. However, those devices will not be used in the same manner as 
fixed devices with gain antennas mounted outdoors that maximize the propagation range of their signals. 
Rather, personal/portable devices will be used indoors, so that their signals will be attenuated by exterior 
walls, and will have a maximum of 0 dBi net antenna gain. These factors will significantly reduce the 
range at which signals from a personal/portable device will be of sufficient field strength to cause 
interference. We believe that these considerations, coupled with the fact that operation of a 
personal/portable device on an upper floor of a building would increase the likelihood of sensing the 
signals of any licensed services in the area, will adequately ensure that unlicensed personal/portable TV 
band devices do not cause interference when used above ground level. 
2. Transmit Power Control 
230. In the First R&O/Further Notice, the Commission proposed to require unlicensed TV 
band devices to incorporate transmit power control (TPC) that would automatically limit emissions to a 
level 6 dB below the maximum permitted transmit power if that level is sufficient to accomplish the 
desired communications.292 It also proposed not to apply the TPC requirement to devices whose 
maximum transmit power capability is at least 3 dB below the maximum permissible transmit power. 
The Commission sought comment on whether it should require a greater range for transmit power control, 
such as the ability to operate 9 or 12 dB below the limits if that is sufficient to achieve the desired 
communications. The Commission has previously applied the proposed TPC provisions to Unlicensed- 
National Information Infrastructure (U-NII) devices that operate in spectrum at 5 GHz.293 The 
Commission also sought comment on whether it should require all devices to use transmit power control 
and to operate with the minimum power necessary to achieve reliable communication,. 
231. The Consumer Electronics Association agrees with the proposed requirements for 
transmit power control and believes that it is not necessary for the Commission to require a greater 
dynamic range because manufacturers will likely go beyond 6 dB as a matter of good design practice.294 
Other parties also support requiring TPC in TV band devices to reduce the potential for interference to 
services in the TV bands, but believe that the Commission should require a dynamic range greater than 6 
dB. Shure supports requiring TV band devices to incorporate TPC and to operate at the minimum power 
needed to conduct desired communication, rather than at the proposed 6 dB reduction, to reduce 
interference to incumbent users and also improve co-existence among unlicensed devices.295 The White 
292 See Further Notice at  45. 
293 See 47 C.F.R.  15.407(h)(1). 
294 See Consumer Electronics Association Further Notice comments at 3. 
295 See Shure Further Notice comments at 16.

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Space Coalition recommends a TPC range of 25 dB, with devices using the minimum power necessary 
for reliable communications, while IEEE 802.18 recommends a 30 dB range with one dB steps between 
power levels.296 The White Space Coalition states that transmit power control can reduce the output 
power of a TV band device to as low as one-third of a milliwatt as appropriate.297 
232. Discussion. The use of transmit power control to avoid using more power than necessary 
for a given communication is a sound spectrum management practice that promotes efficient use of this 
resource. This technique enables communications while minimizing the potential for interference and is 
now a practicable feature for transceivers. We will therefore require all fixed and personal/portable TV 
band devices to incorporate transmit power control to limit their operating power to the minimum 
necessary for successful communication. We are not, however, adopting our proposal to apply the U-NII 
transmit power control requirements to unlicensed TVBDs or to specify alternative operating parameters 
for transmit power control as recommended by some parties. After examining the record and the range of 
power control options recommended by manufacturers, we now conclude that it would be more 
appropriate to simply require that TVBDs limit their operating power to the minimum necessary for 
successful communications and let manufacturers determine the range of power control that is appropriate 
for their individual products. We acknowledge the Consumer Electronics Association statement that 
manufacturers will likely incorporate transmit power control as a matter of good design practice and note 
that the developing IEEE 802.22 standard has provisions for transmit power control with a wide dynamic 
range. We also note that the White Space Coalition states that it intends to incorporate transmit power 
control into its devices. While we are not specifying the technical parameters for transmit power control, 
we will require applicants for certification to describe a devices transmit power control feature 
mechanism in the application. 
3. Out-Of-Band Emissions Limits 
233. In the First R&O/Further Notice, the Commission proposed to require that emissions 
from an unlicensed device outside that devices channel of operation comply with the limits in Section 
15.209 of the rules.298 These are the same out-of-band limits that apply to most intentional radiators 
operating under Part 15 of the rules, and at frequencies above 30 MHz are also the same as the limits that 
apply to most unintentional radiators, including computers and radio and TV receivers. However, the 
Commission recognized the concerns of some parties that these emission levels may be too high for 
devices that operate in the TV bands and sought comment on whether other emission limits would be 
more appropriate. 
234. The White Space Coalition initially argued that the current Section 15.209 out-of-band 
emission limits are adequate to protect against interference, except on adjacent channels.299 However, in 
a subsequent filing, the White Space Coalition recommended that we adopt an out-of-band emissions 
mask that requires emissions from a device to be 55 dB below the highest average power in the band, as 
measured in 500 kHz segments, at the edges of the 6 MHz channel in which the device is operating. 
Tropos Networks believes that the Section 15.247 out-of-band emission limits for spread spectrum and 
296 See White Space Coalition Further Notice reply comments at 6 and IEEE 802.18 Notice comments at 17. 
297 See White Space Coalition Further Notice reply comments at 4. 
298 See Further Notice at  59 and 47 C.F.R.  15.209. 
299 See White Space Coalition Further Notice comments at 29. The White Space Coalition also suggested that 
adjacent channel interference protection can be accomplished using a combination of spectrum sensing and transmit 
power control to meet the adjacent channel D/U ratios. See White Space Coalition Further Notice comments at 15.

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digitally modulated devices should apply to TV band devices, except in restricted bands.300 However, 
other parties, including IEEE 802.18, Shure and NAB/MSTV claim that these limits, which resolve to the 
15.209 limits at low signal levels, are too high and should be substantially reduced for devices operating 
in the TV bands.301 NAB/MSTV argue that the Section 15.209 limits were not problematic previously 
because unlicensed devices were prohibited from operating in the TV band, so that emissions in the TV 
band were far separated in frequency from the channels to which TV receivers tune and therefore well 
below the Section 15.209 limits. They further submit that until recently most unlicensed devices operated 
with narrow bandwidths, so out-of-band emissions were generally narrowband spikes that presented low 
interference risks. MSTV/NAB state that broadband unlicensed TVBDs will have wide out-of-band 
emissions that may be right at the limit. They observe that the Section 15.209 limits are 5 dB higher than 
the 41 dBmV/m field strength of a UHF DTV station at the edge of its protected contour, and in fact need 
to be 23 dB lower than that level to avoid causing interference.302 GE Healthcare believes that the Section 
15.209 limits are not strict enough to protect the WMTS on channel 37 and requests that we adopt a more 
stringent mask for protection of WMTS devices on that channel.303 In an ex parte letter of May 8, 2008, 
Dell, Inc. and Google support GE Healthcares proposal for an emissions mask in channels 36 and 38 to 
protect WMTS devices. CTIA asks the Commission to ensure that operation of unlicensed TV band 
devices do not cause interference to 700 MHz band commercial wireless operations.304 
235. We find that the emissions mask suggested by the Coalition will adequately protect 
against interference from out-of-band emissions from signals at the maximum 40 mW (16 dBm) power 
level that adjacent channels will be allowed to use. At the 10 meter distance we are using for the range at 
which a user can be expected to exercise control of interference, a 40 mW signal propagating over a freespace 
path would produce a signal level of -32 dBm at an indoor receiver using an antenna with 0 dBi 
gain or, in the worst case, -24 dBm radiating directly into an outdoor antenna with 10 dBd (dB reference 
to a dipole) gain and 4 dB cable loss.305 However, we also believe that in the great majority of instances a 
personal/portable device will not transmit directly into a TV gain antenna but rather will be off to the side 
and/or below the rooftop level of the TV antenna so that the received TVBD signal will be picked up at 
less than maximum gain and could in fact be negative. Thus, we will ignore the gain factor of outdoor 
antennas in this analysis and use only the -32 dBm signal level at the edge of a TVBD users premises. 
We also believe that it is appropriate to consider that a TV set or a receiver in some other TV band service 
that might receive interference from a personal/portable TVBD would be located in the premises of 
someone else would be on the other side of some structural elemental such as a wall and therefore, as 
detailed above, assume 10 dB of wall attenuation, 3 dB of polarization mismatch, and an additional 5 dB 
to account for indoor propagation which is generally greater than free space resulting in 18 dB of 
300 See Tropos Networks comments at 13-14. Section 15.247 of the rules which addresses spread spectrum 
transmitters requires out-of-band emissions to be attenuated at least 20 dB below the level of the fundamental signal, 
but in no case less than the Section 15.209 limits. Emissions in restricted bands may not exceed the Section 15.209 
limits. See 47 C.F.R.  15.247. The requirement to attenuate out-of-band emissions 20 dB below the level of the 
fundamental emission may be significantly less stringent than the Section 15.209 limit, depending on the transmitter 
power used. 
301 See IEEE 802.18 Notice comments at 27, Shure Notice comments at 20-21, and NAB/MSTV Notice comments at 
21-24. 
302 See NAB/MSTV Notice reply comments at 22-23. 
303 See GE Healthcare Further Notice comments at 7-8. 
304 See CTIA Further Notice comments at 3. 
305 Free space attenuation of a 600 MHz signal 10 meters from a non-directional antenna is approximately 48 dB. 
The attenuation varies slightly over the TV band depending on the specific frequency of operation.

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attenuation of the TVBD signal, so that the signal would be no higher than -50 dBm in the adjoining 
premise. 
236. The mask suggested by the Coalition would reduce emissions at the edges of the channel 
to -55 dB below the average power level in 500 kHz. Using that mask would reduce the out-of-band 
emissions appearing at a TV receiver to -110 dBm or to 23 dBmV/m at the receivers antenna, which is 
well below the service threshold for DTV reception and the Section 15.209 limit and in fact below the 
noise floor for 6 MHz. This mask is also more restrictive than the DTV emissions mask in the first 
adjacent channel for signals of the same power level. We also see no reason to extend the -23 db weak 
signal signal to noise ratio provision of Section 73.622(c)(3) to protection against adjacent channel 
interference but instead will use the standard 15 db signal-to-noise ratio in that rule section. Given that 
-110 dBm is more than the standard 15 dB signal-to-noise ratio below the -84 dBm DTV reception 
threshold (and is in fact below the -107 dBm thermal noise floor in a 6 MHz channel), we conclude that 
TVBD signals complying with the -55 dB mask will adequately avoid the interference concerns expressed 
by MSTV/NAB. We also observe that the performance of the Adaptrum transmitter demonstrates that 
meeting this mask is feasible. While we believe that the emissions mask is less critical for fixed devices 
that will not operate on adjacent channels, we will require those devices to comply with the same mask as 
personal/portable devices. This will ensure that out-of-band emissions from all TVBDs pose the 
minimum potential for interference. Accordingly, we will require that emissions from unlicensed TVBDs 
be at least 55 dB below the highest average power in the 6 MHz channels adjacent to the 6 MHz channel 
in which the device is operating.306 Beyond 6 MHz from the edge of the operating channel, radiated 
emissions from TVBD devices shall meet the requirements of Section 15.209. In addition, we are 
adopting GE Healthcares proposal for a mask in channels 36 and 38 to protect WMTS devices in channel 
37. All TVBDs will be required to comply with this more stringent requirement for suppression of outof-
band emissions into channel 37. 
4. Spectrum Sensing 
237. As discussed above, we are requiring TVBDs to be capable of detecting DTV stations, 
analog (NTSC) TV stations (because low power analog stations may continue to operate after the DTV 
transition), and wireless microphones at a minimum signal level of -114 dBm. In this section, we discuss 
and specify the technical requirements for spectrum sensing by unlicensed TV band devices. 
238. Detection Bandwidth and Sensing Antenna. In the First R&O/Further Notice, the 
Commission sought comment on the appropriate detection threshold for TV band devices that incorporate 
spectrum sensing. The Commission noted that IEEE 802.22 was considering detection threshold values 
as low as -114 dBm, referenced to an omnidirectional receive antenna with a gain of 0 dBi, and sought 
comment on this value or alternative values for the detection threshold.307 The Commission noted that 
there is a relationship between the sensing receiver bandwidth and ability of a device to detect weak 
signals. A receiver with a wide bandwidth is not able to detect as weak a signal as a receiver using a 
narrow bandwidth because the thermal noise in a receiver is proportional to the bandwidth. The 
Commission sought comment on whether there is a need to specify a sensing bandwidth in addition to a 
306 To determine compliance with the OOBE, the average power, in 500 kHz segments, in the first adjacent 6 MHz 
channel is compared to the highest average power in the 6 MHz channel in which the device is operating. Since the 
resolution bandwidth generally used for making measurements in the 30 MHz to 1000 MHz band is 100 kHz, this 
measurement may be performed using a minimum resolution bandwidth of 100 kHz as long as the same RBW is 
used in both channels. A lower resolution bandwidth may be employed near the band edge, when necessary, 
provided the measured energy is integrated to show the total power over the RBW used to make the in-band 
measurement. 
307 See Further Notice at  37-39.

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detection threshold, or whether it is necessary to specify only the characteristics of the signals to be 
detected as discussed below and leave the sensing bandwidth to the manufacturers discretion.308 Shure 
recommends a detection bandwidth of 200 kHz for wireless microphones.309 
239. IEEE 802.18 believes that the sensing antenna should have a minimum gain of 0 dBi, 
assuming the antenna is omnidirectional, but believes that the Commissions rules should allow 
alternative approaches, such as an electronically rotated high gain antenna that scans 360 degrees.310 
IEEE 802.18 recommends a requirement that the sensing antenna be located outdoors at a minimum 
height of 10 meters above the ground to ensure that it is not shadowed by either terrain or man made 
structures.311 The White Space Coalition is not opposed to a requirement that the receive antenna have a 
gain of 0 dBi, but argues that a minimum sensing height requirement is not practical for personal/portable 
devices.312 
240. We are specifying detection bandwidths for TVBDs to ensure uniformity of detection 
capabilities between devices. We find that a detection bandwidth of 6 MHz is appropriate for digital TV 
because that is the nominal occupied bandwidth of an ATSC signal, a detection bandwidth for analog TV 
is 100 kHz, which is representative of the visual carrier bandwidth of an NTSC signal, and a detection 
bandwidth for wireless microphones is 200 kHz, recommended by Shure and IEEE as being 
representative of the bandwidth in which they typically operate. 
241. As proposed, we will require that the -114 dBm detection threshold be referenced to a 
0 dBi gain receive antenna for both fixed and personal/portable devices. That antenna design will 
maximize the likelihood of sensing signal on an omnidirectional basis. We will also require that the 
receive antenna used with fixed devices be located at least 10 meters above the ground to maximize the 
likelihood that its reception is not blocked from receiving signals originating from any direction. We 
will allow alternative approaches for the sensing antenna, e.g., electronically rotate-able antennas, 
provided the applicant for equipment authorization can demonstrate that its sensing antenna provides at 
least the same performance as an omnidirectional antenna with 0 dBi gain.313 We agree with the White 
Space Coalition that sensing antenna receive height requirements are impractical for personal/portable 
devices and decline to impose such requirements. 
242. Channel Availability Check Time, Move Time, and Non-Occupancy Period. In the First 
R&O/Further Notice, the Commission proposed to require that unlicensed TV band devices that use 
sensing to determine the availability of unused TV band frequencies perform sensing for a certain period 
of time before accessing a channel and periodically thereafter to ensure that the channel is still available, 
i.e., unoccupied.314 The Commission sought comment on whether sensing for 30 seconds would be a 
necessary or sufficient period of time for the initial channel availability check when a device is placed in 
operation, i.e., turned-on. It also proposed to require that devices re-check the channel at least every 10 
seconds to ensure that they are not on the air for extended periods of time causing harmful interference to 
308 See Further Notice at  43. 
309 See Shure Notice comments at 14. 
310 See IEEE 802.18 Further Notice comments at 16. 
311 See IEEE 802.18 Further Notice comments at 12. 
312 See White Space Coalition Further Notice comments at 16. 
313 Minimum directional gain is defined as the antenna gain in the direction and at the frequency that exhibits the 
least gain. 
314 See Further Notice at  40-41.

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authorized services in the TV bands that are not present during an initial sensing check. The Commission 
did not propose to require unlicensed devices to remain off-the-air for any prescribed period of time after 
a channel is first determined to be occupied because it believed that the requirement to perform sensing 
before operating would ensure that devices will not cause harmful interference to authorized services that 
are already on the air. 
243. The White Space Coalition argues that it is not necessary for the Commission to specify a 
channel availability minimum sensing period because the optimum check time will be dictated by the 
algorithms implemented by each manufacturer to meet the minimum detection threshold. It also submits 
that because of the always on nature of services in the TV bands, a re-check interval of one minute is 
more appropriate than 10 seconds, because the shorter 10 second interval would reduce the throughput of 
TV band devices.315 The White Space Coalition states that a period of 10 seconds after detecting a station 
is sufficient and appropriate for a device to vacate a channel, and that it is unnecessary to specify a nonoccupancy 
period because devices would be required to confirm that a channel is unoccupied before 
commencing operation.316 IEEE 802.18 recommends that we require that TV band devices check for the 
presence of wireless microphones every two seconds, but states that a recheck interval of 10 seconds or 
longer is adequate for DTV signals.317 
244. Shure advocates that a TV band device be required to monitor a channel for 30 seconds 
before transmitting to detect wireless microphones that operate intermittently. It believes that an 
unlicensed device should vacate a channel within two seconds after detecting that it is occupied. Shure 
further submits that if the Commission does not adopt a requirement that unlicensed devices to avoid for a 
period of time channels detected as occupied (non-occupancy period), then it should require TV band 
devices to engage in periodic re-sensing every 10 seconds.318 Tropos Networks agrees that the proposed 
30 second channel check and 10 second re-check intervals are reasonable.319 
245. We will require that an unlicensed TV band device perform a channel availability check 
for at least 30 seconds before first accessing a channel each time the device is activated, i.e., powered-up 
after being off. This will allow sufficient time for the TVBDs to ensure that the channel is unoccupied, 
and in particular, to verify that there are no wireless microphones operating intermittently on that channel. 
We will also require that an unlicensed TVBD perform periodic monitoring of channels being used at 
intervals not to exceed one minute. This will ensure that the TVBD can detect the signal of an authorized 
TV band service, particularly wireless microphones, which may commence operation after the device 
begins using a channel. While we did not propose to set a specific time limit within which a TVBD must 
vacate a channel after detecting an authorized user, we conclude that such a requirement is needed to 
ensure that a TVBD device vacates a channel quickly to prevent interference to other users. We therefore 
are requiring that TVBDs vacate a channel found to be occupied subsequent to a devices initial sensing 
operation within a two second interval, as suggested by Shure. This will provide a reasonable time 
315 We note that while wireless microphones tend to operate on an intermittent basis over periods of time, i.e., an 
evening, an afternoon, a one or two hour program, etc., the predominant method of modulation used by those 
devices is frequency modulation (FM) in which the carrier is always on. However, we are also aware that some 
digital wireless microphones are now available that use digital modulation schemes that may or may not be on for 
the full period of an event. 
316 See White Space Coalition Further Notice comments at 14. 
317 See IEEE 802.18 Further Notice comments at 12-14. 
318 See Shure Further Notice comments at 15. 
319 See Tropos Networks Further Notice comments at 10.

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interval for the TVBDs to terminate its use of the channel while minimizing interference to the service 
that has commenced operation on that channel. 
246. We decline to adopt a non-occupancy period during which a TVBD must remain off a 
channel after determining that it is occupied. The requirements to monitor a channel for 30 seconds 
before commencing operation, combined with the requirement to periodically monitor a channel being 
used and quickly vacate when an authorized user begins operation, will adequately protect against 
operation on occupied channels. We recognize the White Space Coalitions concerns that a channel recheck 
interval of ten seconds could affect throughput capacity, and agree that under most circumstances 
the users of the spectrum will not change rapidly and a channel re-check time of one minute should be 
sufficient. 
247. Distributive Sensing and Display of Available Channels. In the First R&O/Further 
Notice, the Commission recognized that distributive sensing, whereby multiple receivers/antennas at 
different locations share sensing information, offers an approach for mitigating the hidden node problem. 
It requested comment on how a distributed sensing approach could be employed on an unlicensed basis. 
The Commission also indicated that it intended to consider other measures that would promote sharing 
and further protection of licensed services by devices using spectrum sensing.320 
248. Shure, the White Space Coalition, and WISPA support requiring unlicensed TV band 
devices to use distributed sensing, although the White Space Coalition believes that a sensing threshold of 
-114 dBm is sufficient to detect TV band signals in any case.321 Shure recommends that we require 
distributed sensing by at least two TV band devices, stating this approach would immensely improve the 
ability of devices to detect wireless microphones and overcome the hidden node problem. WISPA states 
that a distributed sensing approach would improve the ability to detect the signals, and that the 
performance of such capability would improve over time as the number of sensors in an area increases. 
249. We agree with these parties that distributive sensing will improve the ability of 
unlicensed TVBDs to detect the signals of licensed services. Use of this approach will better enable these 
devices to avoid using occupied channels when they are located in hidden nodes or areas where there are 
signal nulls. We are therefore requiring that unlicensed TVBDs communicating in a local area group or 
network, either directly with one another or linked through a common base station, share information on 
channel occupancy determined by sensing. If any device in a local area group or network determines that 
a channel is occupied, all other linked devices will also be required to treat a sensed signal as if they 
detected it themselves. However, we also recognize that the service range of wireless microphones is 
limited to very short distances and that the coverage of a network of TVBDs could extend to areas beyond 
which some TVBDs on the network would not pose a threat to the operation of a detected microphone 
system. We therefore will limit the application of the distributive sensing provision with respect to 
wireless microphones to only require that all TVBDs that are in direct communication with one another 
treat a wireless microphone signal detected by one as if they detected it themselves. 
250. In order to aid users in responding to any complaints of interference that may arise, we 
are also requiring that an unlicensed TVBD be able to provide its user with a list of available channels as 
determined by the TV bands database and sensing. This information could be provided through the 
devices set-up menu or other feature that is readily accessible by the user. While the commenting parties 
did not specifically address this measure, we find that including this capability in unlicensed TVBDs will 
greatly simplify answering questions about the channels they are using and provide a means to readily 
320 See Further Notice at  42 and 47. 
321 See Shure Further Notice comments at 14 and Notice reply comments at 7, White Space Coalition Further Notice 
comments at 17, and WISPA Further Notice reply comments at 3.

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examine whether a device is sensing a licensed TV band service. We also do not believe that inclusion of 
this feature in devices will have a significant cost impact as the current channel availability information 
must be resident in a device at all times in order for it to function in compliance with the rules adopted 
herein. In addition, we are requiring that the user manual for the TVBD include information advising 
consumers of the potential for harmful interference and steps that they can take to identify and remediate 
the interference, such as increasing the separation of the device from other communications equipment 
and contacting the manufacturer for technical assistance. 
5. Measurement Procedures 
251. In the First R&O/Further Notice, the Commission stated that it intended to develop 
interim measurement procedures that will be provided when final rules are adopted. It indicated that 
these procedures would draw on the measurement procedures for 5 GHz U-NII devices, to the extent 
those procedures are relevant to unlicensed devices in the TV bands and the rules it adopts for their 
operation, and its general measurement procedures for unlicensed devices as specified in Section 15.31 of 
the rules.322 The Commission also presented proposals on certain specific measurement issues. With 
regard to testing the sensing detection threshold, it proposed to subject the sensing capabilities of 
unlicensed devices to an ATSC DTV signal, an NTSC signal and a 200 kHz FM signal with peak levels 
adjusted to the threshold level. It also observed that the test procedure for 5 GHz U-NII devices calls for 
performing the detection tests a number of times and specifies pass/fail ratios. The Commission stated 
that it does not believe such an approach is appropriate for detection of TV band signals because it should 
be simpler to detect signals from the types of transmitters operating in the TV spectrum than for radars, 
but invited comment in this regard. 
252. A new measurement procedure is needed for evaluating compliance by unlicensed 
TVBDs with the spectrum sensing and other technical requirements that we are adopting herein. While 
the spectrum sensing requirements for TVBDs are somewhat similar to the U-NII dynamic frequency 
selection (DFS) requirements, as we observed in the First R&O/Further Notice, there are important 
differences between TV band and U-NII devices. For example, TV band devices must be capable of 
detecting signals at a significantly lower threshold than U-NII devices. Also, the types of signals that 
must be detected (TV, wireless microphone, PLMRS/CMRS, and certain other signals) have different 
spectral characteristics than radar signals. Further, there are other new requirements for TVBDs, 
including geo-location accuracy, that are not addressed in any current measurement procedures. Due to 
the complexity of the requirements necessary to protect authorized services in the TV bands, we expect 
that it will take some time to develop the appropriate procedures. We plan to develop these measurement 
procedures as expeditiously as possible. Consistent with the Commissions actions in the U-NII 
proceeding, our Office of Engineering and Technology will release the procedure for unlicensed TV band 
devices when it is completed and the Commission will accept data that has been measured in accordance 
with that procedure pursuant to Section 2.947(a) of the rules.323 
6. Spectrum Sharing 
253. In the First R&O/Further Notice, the Commission stated that it anticipates that industry 
will develop protocol standards that facilitate shared use of the TV white space spectrum.324 It expressed 
concern, however, that in the absence of some minimal mandatory requirements, a single device or 
network of devices could conceivably monopolize use of a channel at a given location or area. The 
322 As indicated above, the U-NII compliance measurement procedure is set forth in the appendix to the 
Memorandum Opinion and Order in ET Docket No. 03-122. See also 47 C.F.R.  15.31. 
323 See 47 C.F.R.  2.947(a)(1). 
324 See Further Notice at  47.

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Commission therefore invited comment as to whether it may be necessary or appropriate for the 
Commission to establish minimal technical requirements to facilitate sharing by TV band devices. It cited 
examples of such requirements that might include limitations on the duration of transmissions and a 
requirement to repeat spectrum sensing at intervals more frequently than ten seconds. 
254. The White Space Coalition states that it is not opposed to a minimal regulatory 
requirement to ensure spectrum sharing among devices. It proposes a maximum channel occupancy time 
of 400 milliseconds, followed by a minimum 100 millisecond interval during which a device may not 
transmit.325 However, IEEE 802.18 opposes restrictions on the duration or duty cycle of unlicensed 
transmissions, arguing that the sharing protocols it is developing will render regulatory restrictions 
unnecessary.326 Tropos believes that Commission requirements to facilitate spectrum sharing would ill 
serve innovation and may undermine the Commissions objective to promote competition.327 CEA 
believes that the Commission should leave any spectrum sharing initiatives in the hands of industry, 
which it claims has proven more facile in adopting self-regulatory standards that improve spectrum 
efficiency than government regulation.328 
255. We see no demonstrated need at this time for mandatory spectrum sharing provisions for 
TVBDs and therefore are not adopting such rules. We also note that the IEEE industry group is already 
developing standards for spectrum sharing between TVBDs. In addition, we are concerned that any 
spectrum sharing requirements we might adopt now could conflict with the developing industry standards 
or otherwise limit manufacturers flexibility in designing TVBDs. We further observe that the 
requirements we are adopting for TVBDs to periodically re-check a channel for availability will prevent a 
device from transmitting continuously. We also advise the involved industries and other interested parties 
that we may revisit this decision in the future if it appears that regulatory requirements for spectrum 
sharing between TVBDs are needed. 
G. Equipment Certification Required 
256. We are requiring TVBDs to be certificated under our equipment authorization program. 
The applicant for an equipment authorization of a device based on geo-location and database access and 
sensing must meet all of the usual requirements for an application for equipment certification as specified 
in Parts 2 and 15 of the FCC rules.329 In addition, we will require an applicant to submit a sample of the 
device for testing at the FCC Laboratory to determine compliance with all of the pertinent requirements 
for a TVBD. The device will only be certified once it has been found through testing to meet all of the 
FCC requirements. This is the process that the Commission has generally followed for new technologies 
that must meet complex standards and raise significant interference concerns. For example, we have 
taken a similar approach relative to certification of ultrawideband devices and to new 5 GHz unlicensed 
devices that include spectrum sensing to avoid causing interference to Department of Defense radars. As 
noted below, we are not allowing certification of TVBDs by Telecommunications Certification Bodies at 
this time. The FCC laboratory will act on such applications under delegated authority pursuant to section 
0.241(b) of the Commissions rules. 
325 See White Space Coalition Further Notice comments at 17. 
326 See IEEE 802.18 Further Notice comments at 18. 
327 See Tropos Networks Further Notice comments at 11. 
328 See CEA Further Notice comments at 5. 
329 See 47 C.F.R. Parts 2 and 15.

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H. Equipment Certification Under A Proof Of Performance Standard 
257. As indicated above, we are providing a special equipment certification procedure for 
approval of sensing only devices that demonstrate the ability to detect protected services with a high level 
of accuracy. In providing this procedure, we recognize that cognitive radio technology, including 
sensing, is in its nascent stage of development for commercial applications. Cognitive radio technology 
holds great promise for increasing access spectrum access to the benefit of consumers and businesses and 
we find it in the public interest to continue to encourage the development of this technology. We also 
recognize that the TV band prototype devices that were submitted to the Commission for evaluation were 
designed primarily to demonstrate the capability of using spectrum sensing for interference avoidance. 
While the devices were able to detect the signals of incumbent services under certain conditions, they 
were not able to do so under others. For example, it does not appear that the devices were designed to 
cope with certain real-world conditions such as strong adjacent channel signals or the challenges of 
operating in noisy environments. This made it particularly difficult to fully validate the performance of 
the technology and develop standards that would ensure a high degree of confidence that devices relying 
on sensing alone would not interfere. Nevertheless, we believe that these problems can be solved. As an 
incentive to continue to develop this technology, we will provide for certification of devices under the 
conditions and process described below. 
258. We therefore are adopting rules that will allow for certification of personal/portable 
devices that rely solely on a spectrum sensing capability and do not include geo-location and database 
access capabilities. These sensing only devices will be required to meet a proof of performance 
standard where they must demonstrate with an extremely high degree of confidence that they will not 
cause harmful interference to incumbent radio services. Devices authorized under this procedure will be 
subject to all rules for personal/portable devices, except that out-of-an abundance of caution with regard 
to their interference potential, such devices will be limited to 50 mW EIRP rather than the 100 mW 
permitted for personal/portable devices that use the geolocation and database method. 
259. Manufacturers must submit an application for certification in accordance with Part 2, 
Subpart J of the Commissions rules. The application must include a full explanation of how the device 
will protect the incumbent radio services against harmful interference. In addition to the procedures of 
Part 2, Subpart J of the Commissions rules, the applicant must submit a pre-production sample for 
laboratory and field testing. The pre-production sample device must be identical to the device expected to 
be marketed. 
260. The Commission will process this application in the following manner. Applications will 
be placed on Public Notice for a minimum of 30 days for comments and 15 days for reply comments. 
Applicants may request that portions of their application remain confidential in accordance with section 
0.459 of this chapter. This Public Notice will include proposed test procedures and methodologies. After 
the comment period, the Commission will test the devices to evaluate proof of performance, including 
characterization of its sensing capability and its interference potential. The testing will be open to the 
public. Subsequent to the completion of testing, the Commission will issue by Public Notice, a test report 
including recommendations. The Public Notice will specify a minimum of 30 days for comments and, if 
any objections are received, an additional 15 days for reply comments. The ultimate decision on whether 
to certify a device that relies solely on sensing will be made by the full Commission. 
261. The determination of whether to certify the device will be based on a demonstrated 
ability to avoid causing harmful interference with an extremely high degree of reliability. As noted 
above, there has been much discussion in this proceeding as to the effectiveness of sensing at particular 
levels. We note that we are adopting a detection threshold of -114 dBm for devices that rely on 
geolocation and database access. However, this particular level may or may not be the appropriate 
sensing threshold for these sensing only devices. The decision by the Commission whether to certify the 
equipment will rest on its performance in avoiding interference, not any particular sensing level. If the 

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device is certificated, we will permit routine certification of other devices that have identical 
characteristics (i.e., have the identical electrical characteristics and antenna system). We will endeavor to 
complete the certification process within 180 days of submittal of the device for testing, barring any 
unforeseen circumstances. 
I. Other Matters 
1. Certification By Telecommunications Certification Bodies 
262. In the First R&O/Further Notice, the Commission proposed that Telecommunications 
Certification Bodies (TCBs) initially not be permitted to certify TV band devices because these devices 
would contain new technologies and many questions about the application of the rules may arise.330 
Specifically, the Commission proposed to place TV band devices on the list of types of devices that TCBs 
are excluded from certifying until it has more experience with them and can advise TCBs on the 
application of the rules.331 Both the Consumer Electronics Association and Shure support this proposal 
and no parties opposed it.332 We continue to believe that we should exclude TCBs from granting 
applications for certification of unlicensed TV band devices at this time for the reasons indicated above. 
We will therefore limit the processing of those applications to our Laboratory Division until such time as 
we gain experience with unlicensed TVBDs and the technology used in those products becomes mature 
such that the application review process becomes routine. Accordingly, we will not allow TCBs to certify 
TV band devices until further notice. 
2. Operation In Border Areas 
263. The allotment and assignment of TV channels in the border areas with Canada and 
Mexico are subject to agreements with each of those countries. Low power TV assignments within 32 
kilometers (20 miles) of the Canadian border must be referred to the Canadian authorities for approval.333 
In addition, low power UHF TV stations that are located less than 40 kilometers (25 miles) from the 
Mexican border, and low power VHF TV stations that are less than 60 kilometers (37 miles) from the 
Mexican border, must be referred to the Mexican government for approval.334 In the Notice, the 
330 See Further Notice at  64. All unlicensed transmitters and most licensed transmitters are required to be certified 
by the Commission or a designated Telecommunication Certification Body (TCB) before they may be legally 
marketed within the United States. In establishing the requirements for TCBs, the Commission stated that while it 
intended to allow TCBs to certify a broad range of equipment, certain functions should continue to be performed by 
the Commission. These functions include certifying new or unique equipment for which the rules or requirements 
do not exist or for which the application of the rules is not clear. 
331 The Commissions Laboratory maintains a list of types of devices that TCBs are excluded from certifying. Once 
it determines that TCBs have the necessary expertise to certify an excluded device, the Laboratory will remove it 
from the list. 
332 See Consumer Electronics Association comments at 7 and Shure comments at 21. 
333 See Working Arrangement for Allotment and Assignment of VHF and UHF Television Broadcasting Channels 
under the Agreement between the Government of the United States of America and the Government of Canada 
Relating to the TV Broadcasting Service, dated March 1, 1989. This agreement is available on the Commissions 
web site at http://www.fcc.gov/ib/sand/agree/files/can-bc/can-tv.pdf. 
334 See Agreement Amending the Agreement Relating to Assignments and Usage of Television Broadcasting 
Channels in the Frequency Range 470-806 MHz (Channels 14-69) along the United States-Mexico Border, dated 
November 21, 1988. This agreement is available on the Commissions web site at 
http://www.fcc.gov/ib/sand/agree/files/mex-bc/lpuhfbc.pdf. See also, the untitled amendment to the United States- 
Mexican agreement on VHF stations dated September 14-26, 1988, available on the Commissions web site at 
http://www.fcc.gov/ib/sand/agree/files/mex-bc/lpvhfbc.pdf. The agreements may require coordination at greater 
distances from the border depending on the ERP and HAAT of the LPTV station. 

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Commission proposed to prohibit unlicensed TV band devices from operating at less than these distances 
from the Canadian and Mexican borders until agreements are reached with those countries.335 The 
Commission also sought comment on how to ensure that unlicensed devices using vacant TV channels do 
not operate within the border areas and whether the methods used to ensure that these devices operate 
only on vacant TV channels could be adapted to preclude operation in the border areas. In the First 
R&O/Further Notice, the Commission sought comment on whether the agreements with Canada and 
Mexico would need to be modified before unlicensed TV band devices could operate in the border 
areas.336
264. The White Space Coalition argues that the agreements with Canada and Mexico do not 
need to be modified because they relate to restrictions on TV station operations and not on devices that 
operate in the TV bands using significantly less power than TV stations. It further argues that the use of 
unlicensed TV band devices is not inconsistent with those agreements, assuming the devices use spectrum 
sensing to avoid Canadian and Mexican TV signals.337 NAF, et al., believe that given the low power and 
sensing capabilities proposed in this proceeding, there is no risk to either Canadian or Mexican television 
operations. They also believe that geo-location is another reliable option. The NAF, et al., also submit 
that the Commission should interpret the legal requirement for coordination as existing only where a 
device can potentially interfere.338 IEEE 802.18 states that operation of fixed devices can easily be 
controlled using geo-location to ensure that they do not violate the necessary separation from the 
border.339 
265. We find that fixed TV band devices should not be permitted to operate within the border 
areas specified in our Canadian and Mexican agreements until we have an opportunity to negotiate any 
necessary changes to those agreements with Canada and Mexico. The fixed TV band devices that operate 
with outdoor antennas at an EIRP of up to 4 watts will be somewhat similar in operation to low power TV 
stations. Therefore, in keeping with the low power broadcasting agreements with Canada and Mexico, we 
will not permit fixed TV band devices to operate on any channels within 32 kilometers of the Canadian 
border, within 40 kilometers of the Mexican border on UHF channels, or within 60 kilometers of the 
Mexican border on VHF channels.340 These distance restrictions will be enforced through the use of a 
devices geo-location and database access capabilities, which all fixed devices must incorporate. 
266. We will apply these same restrictions on the use of unlicensed personal/portable TV band 
devices within the border areas. While personal/portable devices will operate with significantly lower 
power, in order to avoid any uncertainty in administering our agreements with our neighboring 
administrations, we believe it is also necessary to restrict operation of those devices in the border areas. 
Personal/portable devices that operate in Mode II using a geo-location/database access capability will be 
required to use that capability to determine whether they are located in a border area. Devices operating 
in Mode I on a client basis without a geo-location/database access capability will be prevented from 
operating in the border areas in that they will operate relatively close to an associated base station (fixed 
or personal/portable) that uses a geo-location/database access capability that will keep it from operating in 
335 See Notice at  46. 
336 See First R&O/Further Notice at  65. 
337 See White Space Coalition Further Notice comments at 30-31. 
338 See NAF, et al. Further Notice comments at 87-88. 
339 See IEEE 802.18 Further Notice comments at 24. 
340 The distances we specify are the minimums specified in the agreements because those distances would apply to a 
station with the proposed maximum unlicensed device power of 1 watt into a 6 dBi gain antenna (2.43 watts ERP).

Federal Communications Commission FCC 08-260 
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the border areas. The requirement that all personal/portable devices incorporate sensing to a level of -114 
dBm will further minimize the risk of interference to TV stations in Canada and Mexico. 
3. Reconsideration Of Marketing Date For Unlicensed TV Band Devices 
267. In their Petition for Reconsideration, NAF/CUWN request that we reverse our decision to 
prohibit the marketing of TV white space devices until the DTV transition ends on February 17, 2009, 
and instead authorize marketing of such devices as soon as we develop rules and certify that devices 
comply with them. NAF/CUWN argue that there is no technical reason why devices using any of the 
mechanisms the Commission will approve cannot operate prior to the analog switch off date. They also 
contend that if the transition is to go smoothly, the vast majority of stations must be converted to digital 
operation and the public must be ready to receive digital signals well before February 17, 2009. They 
further argue that delays will impose considerable and needless costs on the public. NAF/CUWN state 
that because TVBDs will represent new devices operating under new rules, developers will need to start 
from scratch when innovating with the new equipment rather than simply building on past experience and 
existing software. They contend that the sooner the Commission allows properly certified devices on the 
market, the sooner the learning and experimentation can begin. 
268. We are maintaining our decision to prohibit the marketing of unlicensed TV band devices 
until the DTV transition ends on February 18, 2009. In this regard, we remain concerned that allowing 
operation of unlicensed devices during the transition period could cause uncertainty for the broadcast 
television about possible interference. For example, in the transition period stations will be changing 
channels and otherwise operating in manners that are temporary. This changing pattern of TV channel 
usage will affect the availability of channels that could be used by unlicensed devices. We believe that it 
is quite reasonable for broadcasters to be uncertain about whether their services are adequately protected 
from interference from unlicensed devices in such an environment. We further note that, as reflected in 
the issues raised in the third DTV period review, all stations will not be fully converted well before the 
end of the transition.341 We also are not persuaded by NAF/CUWNs argument that the proscription on 
marketing of unlicensed TVBDs until the transition ends will impede the development of unlicensed 
TVBDs. That development process, including completion of the certification requirement, can take place 
prior to the actual marketing of devices. Given that there are only a few months remaining before the end 
of the transition, the period of time between when devices are certified and otherwise ready for marketing 
and the end of the transition will be long in any case. 
4. Emergency Request For Additional Comment Period 
269. On October 17, 2008, several broadcast interests filed an Emergency Request asking 
the Commission to issue a public notice seeking comment on the Phase II Test Report.342 The requesters 
contend that the report expresses conclusions that are not supported by the data in the report and that the 
public has not had opportunity to review and comment meaningfully on the results of the report. This 
request is denied. The testing process has been open and members of the public, including persons 
representing the requesters and their interests, have observed the testing and have been privy to the data as 
it was collected. All have had opportunity on a continuing basis to comment and they have done so, as 
has been demonstrated in numerous ex parte submissions related to, referring to, or based on the testing. 
341 See Notice of Proposed Rulemaking in MB Docket No. 07-91, supra. 
342 See Emergency Request filed by The Association For Maximum Service Television, Inc., The National 
Association of Broadcasters, The ABC, NBC, CBS, and FOX Television Networks, and The Open Mobile Video 
Coalition, filed Oct. 17, 2008.

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V. PROCEDURAL MATTERS 
A. Final Regulatory Flexibility Analysis 
270. The Final Regulatory Flexibility Analysis, required by the Regulatory Flexibility Act, see 
5 U.S.C.  604, is contained in Appendix B. 
B. Final Paperwork Reduction Act of 1995 Analysis 
271. This Second Report and Order contains new or modified information collections subject 
to the Paperwork Reduction Act of 1995 (PRA) and will be submitted to the Office of Management and 
Budget (OMB) for review under Section 3507(d) of the PRA, Public Law 104-13. A modification is 
required to the Form 731 (OMB 3060-0057). 
C. Contact Persons 
272. For additional information concerning this Second Report and Order and Memorandum 
Opinion and Order, please contact Mr. Hugh L. Van Tuyl at (202) 418-7506, Mr. Nicholas Oros at (202) 
418-0636, or Mr. Alan Stillwell at (202) 418-2925, or via the Internet at Hugh.VanTuyl@fcc.gov, 
Nicholas.Oros@fcc.gov, and Alan.Stillwell@fcc.gov, respectively. 
VI. ORDERING CLAUSES 
273. Accordingly, IT IS ORDERED that, pursuant to the authority contained in Sections 4(i), 
302, 303(e), 303(f), and 307 of the Communications Act of 1934, as amended, 47 USC Sections 154(i), 
302, 303(c), 303(f), and 307 this Second Report and Order IS HEREBY ADOPTED. 
274. IT IS FURTHER ORDERED that Part 15 of the Commission's rules IS AMENDED as 
specified in Appendix B, and such rule amendments shall be effective 30 days after publication of the text 
thereof in the Federal Register. This Second Report and Order contains information collection 
requirements subject to the Paperwork Reduction Act of 1995 (PRA), Public Law 104-13, that are not 
effective until approved by the Office of Management and Budget. The Federal Communications 
Commission will publish a document in the Federal Register following approval of the information 
collection by the Office of Management and Budget ("OMB") announcing the effective date of those 
rules. 
275. IT IS FURTHER ORDERED that, pursuant to Sections 4(i), 302, 303(e) 303(f), 303(g), 
303(r) and 405 of the Communications Act of 1934, as amended, 47 U.S.C.  154(i), 302, 303(e), 
303(f), 303(g), 303(r) and 405, the petition for reconsideration filed by the New America Foundation and 
the Champaign Urbana Wireless Network IS DENIED. 
276. IT IS FURTHER ORDERED that, pursuant to Sections 4(i), 302, 303(e) 303(f), 303(g), 
and 303(r) of the Communications Act of 1934, as amended, 47 U.S.C.  154(i), 302, 303(e), 303(f), 
303(g) and 303(r), the Emergency Request filed by The Association For Maximum Service Television, 
Inc., The National Association of Broadcasters, The ABC, NBC, CBS, and FOX Television Networks, 
and The Open Mobile Video Coalition IS DENIED.

Federal Communications Commission FCC 08-260 
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277. IT IS FURTHER ORDERED that the Commissions Consumer and Governmental 
Affairs Bureau, Reference Information Center, SHALL SEND a copy of the Second Report and Order, 
including the Final Regulatory Flexibility Analysis, to the Government accountability Office pursuant to 
the Congressional Review Act, see 5 U.S.C. 801(a)(1)(A). 
FEDERAL COMMUNICATIONS COMMISSION 
Marlene H. Dortch 
Secretary

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APPENDIX A 
Parties Filing Comments 
Comments on NPRM 
1. Adaptrum, Inc. 
2. Alan Greagor 
3. Association of Public Safety 
Communications Officials 
4. Association of Public Television Stations 
5. ATK Audiotek 
6. Attron Networks, LLC 
7. Audio-Technica U.S., Inc. 
8. Chip Brown 
9. Chuck Profito 
10. Cohen, Dippell and Everist, P.C. 
11. Commercial Broadcasting Corporation 
12. Community Broadcasters Association 
13. Consumer Electronics Association 
14. County of Los Angeles 
15. Cox Broadcasting, Inc. 
16. CWLab 
17. Dan Lubar 
18. Dustin Goodwin 
19. Entravision Holdings, LLC 
20. Harris Corporation 
21. IEEE 802 
22. Industrial Telecommunications Association, 
Inc. 
23. Intel Corporation 
24. International Communications Industries 
Association, Inc. 
25. Itron, Inc. 
26. James M. McKinion 
27. James Stoffo 
28. John Laprise 
29. John Notor 
30. John Terrill 
31. Jon M. Peha 
32. Josephson Engineering, Inc. 
33. Karl Winkler 
34. Kenneth DiPietro 
35. Kenneth Youngquist 
36. KHEM Television 
37. Lee Good, RTS 
38. Mark Koskenmaki 
39. Marlon K. Schafer 
40. Metropolitan Area Networks, Inc. 
41. Michael Falaschi 
42. Michael J. Marcus 
43. Michael Mason 
44. Michiana Wireless 
45. Microsoft Corporation 
46. Motorola, Inc. 
47. NAB and MSTV 
48. NAMM, the International Music Products 
Association 
49. National Academy of Sciences 
50. National Cable & Telecommunications 
Association 
51. National Radio Astronomy Observatory 
52. National Systems Contractors Association 
53. National Translator Association 
54. New America Foundation, et al. 
55. Noah Miller 
56. NPG of Oregon, Inc. 
57. NYCwireless.net 
58. Old Colorado City Communications 
59. OnlyInternet Broadband & Wireless, Inc. 
60. Pappas Telecasting Companies 
61. Paul Burkholder 
62. Pikes Peak Broadcasting Company 
63. Professional Audio Manufacturers Alliance 
64. PVT Networks, Inc. 
65. QUALCOMM Incorporated 
66. R. Kent Parsons 
67. Raymond D. Meredith, Jr. 
68. Rebekah Morris 
69. Red River Broadcasting Co., LLC 
70. Region 1 Translator Association 
71. Ron Wallace 
72. Ronald E. Wallace 
73. Sascha D. Meinrath 
74. Sennheiser Electronic Corporation 
75. Shared Spectrum Company 
76. Shure Incorporated 
77. Society of Broadcast Engineers, Inc. 
78. Southwest Colorado TV Translator 
Association 
79. Stelios Valavanis 
80. Symmetrical Networks, Inc. 
81. Syncom Media Group, Inc. 
82. Telecommunications Industry Association 
83. Telex Communications, Inc. 
84. Tim Foster 
85. Tony Ray 
86. Total RF Marketing, Inc.

Federal Communications Commission FCC 08-260 
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87. Tropos Networks 
88. Vaxeo.com 
89. WDLP Broadcasting Co., LLC 
90. White Pine Television District No. 1 
91. Wi-Fi Alliance 
92. Wireless Broadband Operators Coalition 
93. Wireless Internet Service Providers 
Association 
94. Wireless Unleashed 
95. Yochai Benkler 
96. Zachary C. Miller 
Reply Comments on NPRM 
1. 700 MHz Advancement Coalition 
2. Alan B. Greager 
3. Allcom Communications, Inc. 
4. BPS Networks 
5. Brendan Geaney 
6. Cameron Communications Corporation 
7. Cohen, Dippell and Everist, P.C. 
8. Community Broadcasters Association 
9. Consumer Electronics Association 
10. EarthLink, Inc. 
11. Information Technology Industry Council 
12. Intel Corporation 
13. KBDI, Channel 12 
14. Kennebec Telephone Company 
15. Land Mobile Communications Council 
16. Lanham Rattan 
17. Motorola, Inc. 
18. NAB and MSTV 
19. NARTE 
20. National Translator Association 
21. New America Foundation, et al. 
22. North Dakota Network Company 
23. OnTarget Technologies, LLC 
24. Pitkin County FM-TV Department 
25. Ponderosa Telephone Company 
26. PVT Networks, Inc. 
27. QUALCOMM Incorporated 
28. Red River Rural Telephone Association 
29. Shared Spectrum Company 
30. Shure Incorporated 
31. Society of Broadcast Engineers, Inc. 
32. Timothy X Brown 
33. Webster Calhoun Cooperative Telephone 
Association 
Comments on Further NPRM 
1. Advanced Broadband Solutions, Inc. 
2. American Society for Healthcare 
Engineering  ASHE 
3. American Federation of Television and 
Radio Artists 
4. Comm Enterprises, LLC 
5. Communications Research Centre Canada 
6. Community Broadcasters Association 
7. CompTIA 
8. Consumer Electronics Association 
9. County of Los Angeles 
10. Cox Broadcasting, Inc. 
11. CTIA  The Wireless Association 
12. Dell, Google, HP, Intel, Microsoft and 
Philips (The Coalition) 
13. Entravision Holdings, LLC 
14. GE Healthcare 
15. Guitar Center, Inc. 
16. IEEE 802.18 Radio Regulatory Technical 
Advisory Group 
17. ION Media Networks 
18. Itron, Inc. 
19. James R. McDonald 
20. Joint Comments of Broadcasters 
21. Kenneth E. Lewetag 
22. KJLA, LLC 
23. Land Mobile Communications Council 
24. Martin J. Jackson 
25. McGraw-Hill Broadcasting Company, Inc. 
26. Media General, Inc. 
27. Motorola, Inc. 
28. MSTV & NAB 
29. National Cable and Telecommunications 
Association 
30. National Translator Association 
31. National Radio Astronomy Observatory 
32. Qualcomm Incorporated 
33. R. Kent Parsons 
34. Radio-Television News Directors 
Association 
35. Recording Artists Coalition 
36. Region 1 Translator Association 
37. Shure, Inc. 
38. The Brattle Group 
39. The Professional Audio Manufacturers 
Alliance 
40. The National Academy of Recording Arts 
and Sciences 
41. Tropos Networks 
42. TV Transmission Antenna Group, Inc. 

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43. Wi-Fi Alliance 
44. Microphone Interests Coalition 
45. NAF, et al. 
46. Thomas C. Smith 
Reply comments on Further NPRM 
1. Audio-Technica U.S., Inc. 
2. Capitol Broadcasting Company, Inc. 
3. DC Access, LLC 
4. Dell, Google, HP, Intel, Microsoft and 
Philips (The Coalition) 
5. EchoStar Satellite LLC 
6. Grand Ole Opry and Microphone Interests 
Coalition 
7. Hubbard Broadcasting Company, Inc. 
8. Motorola, Inc. 
9. MSTV and NAB 
10. NAMM, The International Music Products 
Association 
11. National Translator Association 
12. National Cable and Telecommunications 
Association 
13. NAF, et al 
14. NextWave Broadband, Inc. 
15. Professional Audio Manufacturers Alliance 
16. Roadstar Internet 
17. Shure, Inc. 
18. The Brattle Group 
19. Tropos Networks 
20. Wireless Internet Service Providers 
Association 
Comments on Technical Reports 
1. Cohen, Dippell and Everist, P.C. 
2. Community Broadcasters Association 
3. DTV Manufacturers 
4. LG Electronics, Panasonic and TTE 
5. Microphone Interests Coalition 
6. Microtune, Inc. 
7. Motorola, Inc. 
8. MSTV and NAB 
9. NAF, et al. 
10. National Cable & Telecommunications 
Association 
11. Philips Electronics North America 
Corporation 
12. Samsung Electronics 
13. Shure, Inc. 
14. Sony Electronics, Inc. 
15. Sprint Nextel Corporation 
16. White Space Coalition 
In addition to the above-listed comments, over 30,000 parties submitted filings outside of the 
Commissions designated comment and reply comment periods.

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APPENDIX B 
Final Rules 
Part 15 of Title 47 of the Code of Federal Regulations is amended as follows: 
1. The authority citation of Part 15 continues to read as follows: 
AUTHORITY: 47 U.S.C. 154, 302a, 303, 304, 307, 336, and 544a 
2. Section 15.37 is amended by adding a new paragraph (n) to read as follows: 
Section 15.37 Transition provisions for compliance with the rules. 
* * * * * 
(n) Marketing of TV band devices operating under Subpart H of this section is not permitted prior to 
February 18, 2009. 
3. A new Subpart H is added to read as follows: 
Subpart H  Television Band Devices 
Section 15.701 Scope. 
This subpart sets out the regulations for Television Band Devices (TVBDs) which are unlicensed 
intentional radiators operating on available channels in the broadcast television frequency bands at 54-60 
MHz, 76 - 88 MHz, 174 - 216 MHz, 470 - 608 MHz and 614 - 698 MHz bands. 
Section 15.703 Definitions. 
(a) Available Channel. A television channel which is not being used by an authorized user at or near the 
same geographic location as the TVBD and is acceptable for use by an unlicensed device under the 
provisions of Section 15.709 of this chapter. A TVBD determines television channel availability either 
from the TV bands database or Spectrum Sensing. 
(b) Client Device. A TVBD operating in Client Mode. 
(c) Client Mode. An operating mode in which the transmissions of the TVBD, including frequencies of 
operation, are under control of the Master Device. A device in client mode is not able to initiate a 
network. 
(d) Fixed Device. A TVBD that transmits and/or receives radiocommunication signals at a specified 
fixed location. Fixed TVBDs may operate as part of a system, transmitting to one or more fixed TVBDs 
or to personal/portable TVBDs. 
(e) Geo-location. The capability of a TVBD to determine its geographic coordinates within a specified 
level of accuracy. 
(f) Master Device. A TVBD operating in Master Mode. 
(g) Master Mode. An operating mode in which the TVBD has the capability to transmit without 
receiving an enabling signal. The TVBD is able to select a channel itself and initiate a network by sending 
enabling signals to other devices. A network always has at least one device operating in master mode.

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(h) Mode I Operation. Operation of a personal/portable TVBD operating only on the Available Channel 
identified by either the fixed TVBD or Mode II TVBD that enables its operation. Mode I operation does 
not require use of a Geo-location capability or access to the TV bands database and requires operation in 
Client Mode. 
(i) Mode II Operation. Operation of a personal/portable TVBD whereby the device determines the 
Available Channels at its location using its own Geo-location and TV bands database access capabilities. 
Devices operating in Mode II may function as Master Devices. 
(j) Network Initiation. The process by which a fixed or Mode II TVBD sends control signals to another 
similar device or to a Client Devices(s) and allows them to begin transmissions. 
(k) Operating Channel. An Available Channel used by a TVBD for transmission and/or reception. 
(l) Personal/portable Device. A TVBD that transmits and/or receives radiocommunication signals while 
in motion or at unspecified locations. 
(m) Receive site. The location where the signal of a full service station is received for rebroadcast by a 
television translator or low power TV, including Class A TV, station. 
(n) Spectrum Sensing. A process whereby a TVBD listens to a television channel to detect whether the 
channel is occupied by a radio signal. 
(o) Television band device (TVBD). Intentional radiators operating on Available Channels in the 
broadcast television frequency bands at 54-60 MHz, 76-88 MHz, 174-216 MHz, 470-608 MHz and 614- 
698 MHz. 
(p) TV bands database. A database of authorized services in the TV frequency bands that is used to 
determine the Available Channels at a given location for use by TVBDs. 
Section 15.705 Cross reference. 
(a) The provisions of Subparts A, B, and C of this part apply to TVBDs, except where specific provisions 
are contained in subpart H. 
(b) The requirements of subpart H apply only to the radio transmitter contained in the TVBD. Other 
aspects of the operation of a TVBD may be subject to requirements contained elsewhere in this chapter. 
In particular, a TVBD device that includes a receiver that tunes within the frequency range specified in 
Section 15.101(b) or contains digital circuitry not directly associated with the radio transmitter is also 
subject to the requirements for unintentional radiators in subpart B. 
Section 15.706 Information to the user. 
(a) For TV band device, the instructions furnished the user shall include the following or similar 
statement, placed in a prominent location in the text of the manual: 
NOTE: This equipment has been tested and found to comply with the 
rules for TV band devices, pursuant to Part 15 of the FCC Rules. These 
rules are designed to provide reasonable protection against harmful 
interference. This equipment generates, uses and can radiate radio 
frequency energy and, if not installed and used in accordance with the 

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instructions, may cause harmful interference to radio communications. 
However, there is no guarantee that interference will not occur in a 
particular installation. If this equipment does cause harmful interference 
to radio or television reception, which can be determined by turning the 
equipment off and on, the user is encouraged to try to correct the 
interference by one or more of the following measures: 
- Reorient or relocate the receiving antenna. 
- Increase the separation between the equipment and receiver. 
- Connect the equipment into an outlet on a circuit different 
from that to which the receiver is connected. 
- Consult the manufacturer, dealer or an experienced radio/ 
TV technician for help. 
(b) In cases where the manual is provided only in a form other than paper, such as on a computer disk or 
over the Internet, the information required by this section may be included in the manual in that 
alternative form, provided the user can reasonably be expected to have the capability to access 
information in that form. 
Section 15.707 Permissible Channels of operation. 
(a) All TVBDs are permitted to operate in the frequency bands 512-608 MHz and 614-698 MHz, except 
that in the 13 metropolitan areas listed Section 90.303(a) of this chapter and nearby areas where private 
land mobile services and commercial land mobile services are authorized by waiver, operation of TVBDs 
is prohibited on the first available channel on each side of TV channel 37 (608-614 MHz). These channels 
will be listed in the TV bands database. 
(b) Operation in the bands 54-60 MHz, 76-88 MHz, 174-216 MHz, 470-512 MHz is permitted only for 
fixed TVBDs that communicate only with other fixed TVBDs. 
(c) Fixed and Mode II TVBDs shall only operate on available channels as determined by the TV bands 
database and in accordance with the interference avoidance mechanisms of section 15.711 of this part. 
(d) Mode I TVBDs shall only operate on available channels provided to it from a Fixed or Mode II 
TVBD. 
Section 15.709 General technical requirements. 
(a) Power limits for TVBDs are as follows: 
(1) For fixed TVBDs, the maximum conducted output power over the TV channel of operation 
shall not exceed one watt. Transmitter power will be measured at the antenna input to account for 
any cable losses between the transmitter and the antenna. If transmitting antennas of directional 
gain greater than 6 dBi are used, the maximum conducted output power shall be reduced by the 
amount in dB that the directional gain of the antenna exceeds 6 dBi. 
(2) For personal/portable TVBDs, the maximum conducted output power over the TV channel of 
operation shall not exceed 100 milliwatts; except that for personal/portable TVBDs that do not 
meet the adjacent channel separation requirements in Section 15.712(a), the maximum conducted 
output power shall not exceed 40 milliwatts. If transmitting antennas of directional gain greater 
than 0 dBi are used, the maximum conducted output power shall be reduced by the amount in dB 
that the directional gain of the antenna exceeds 0 dBi. 

Federal Communications Commission FCC 08-260 
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(3) TVBDs shall incorporate transmit power control to limit their operating power to the 
minimum necessary for successful communication. Applicants for certification shall include a 
description of a devices transmit power control feature mechanism. 
(4) Maximum conducted output power is the total transmit power in the entire emission 
bandwidth delivered to all antennas and antenna elements averaged across all symbols in the 
signaling alphabet when the transmitter is operating at its maximum power control level. Power 
must be summed across all antennas and antenna elements. The average must not include any 
time intervals during which the transmitter is off or is transmitting at a reduced power level. If 
multiple modes of operation are possible (e.g., alternative modulation methods), the maximum 
conducted output power is the highest total transmit power occurring in any mode. 
(b) Antenna requirements. 
(1) For personal/portable TVBDs, the antenna shall be permanently attached. 
(2) The receive antenna used with fixed devices shall be located outdoors at least 10 meters above 
the ground. The antenna system shall be capable of receiving signals of protected services 
equally in all directions. The transmit antenna used with fixed devices may not be more than 30 
meters above the ground. 
(3) For both Fixed and personal/portable TVBDs, the provisions of Section 15.204(c)(4) do not 
apply to the receive antenna used for spectrum sensing. 
(c) Undesirable emission limits for TVBDs are as follows: 
(1) In the 6 MHz channels adjacent to the operating channel, emissions from TVBD devices shall 
be at least 55 dB below the highest average power in the band. 
(2) The above emission measurements shall be performed using a minimum resolution bandwidth 
of 100 kHz with an average detector. A lower resolution bandwidth may be employed near the 
band edge, when necessary, provided the measured energy is integrated to show the total power 
over 100 kHz. 
(3) At frequencies beyond 6 MHz from the edge of the operating channel, radiated emissions 
from TVBD devices shall meet the requirements of Section 15.209 of this part. 
(4) Emissions in the band 602  620 MHz must also comply with the following field strength 
limits at a distance of one meter. 
Frequency (MHz) Field Strength 
dBV/meter/120 kHz 
602 - 607 120  5[F(MHz)  620] 
607 - 608 95 
608 - 614 30 
614 - 615 95 
615 - 620 120  5[620  F(MHz)] 
(5) TVBDs connected to the AC power line are required to comply with the conducted limits set 
forth in Section 15.207 of this part.

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(d) Compliance with radio frequency exposure requirements. To ensure compliance with the 
Commissions radio frequency exposure requirements in  1.1307(b), 2.1091 and 2.1093 of this chapter, 
fixed TVBDs shall be accompanied by instructions on measures to take to ensure that persons maintain a 
distance of at least 40 cm from the device, as well as any necessary hardware that may be needed to 
implement that protection. These instructions shall be submitted with the application for certification. 
Personal/portable TVBDs that meet the definition of portable devices under Section 2.1093 of this chapter 
and that operate with a source-based time-averaged output of less than 20 mW will not be subject to 
routine evaluation for compliance with the radio frequency exposure guidelines, while devices that 
operate with a source-based time-average output power greater than 20 mW will be subject to the routine 
evaluation requirements. 
Section 15.711 Interference avoidance mechanisms. 
(a) Except as provided in Section 15.717, television channel availability for a TVBD is determined based 
on either the geo-location and database access mechanism described in paragraph (b) of this section or 
spectrum sensing described in paragraph (c) of this section. 
(1) A TVBD shall rely on the geo-location and database access mechanism to identify available 
television channels consistent with the interference protection requirements of Section 15.712. 
Such protection will be provided for the following authorized services: digital television stations, 
and digital and analog Class A, low power, translator and booster stations; translator receive; 
fixed broadcast auxiliary service links; private land mobile service/ commercial radio service 
(PLMRS/CMRS) operations; offshore radiotelephone service; and cable system head-ends. In 
addition, protection shall be provided in border areas near Canada and Mexico in accordance with 
Section 15.712(g) of this part. 
(2) For low power auxiliary services authorized pursuant to Section 74.801-74.882 of this 
chapter, including wireless microphones, a TVBD shall rely on the geo-location and database 
access mechanism to identify available television channels to provide interference protection to 
registered locations of such operations, consistent with the requirements of Section 15.722, and 
shall rely on spectrum sensing to identify available television channels to provide interference 
protection to all other operations. 
(b) Geo-location and database access. 
(1) The geographic coordinates of a fixed TVBD shall be determined to an accuracy of +/- 50 
meters by either an incorporated geo-location capability or a professional installer. In the case of 
professional installation, the party who registers the fixed TVBD in the database will be 
responsible for assuring the accuracy of the entered coordinates. The geographic coordinates of a 
fixed TVBD shall be determined at the time of installation and first activation from a power-off 
condition, and this information may be stored internally in the TVBD. If the fixed TVBD is 
moved to another location or if the stored coordinates become altered, the operator shall reestablish 
its geographic location and store this information in the TVBD either by means of the 
devices incorporated geo-location capability or through the services of a professional installer. 
(2) A Mode II personal/portable device shall incorporate a geo-location capability to determine its 
geographic coordinates to an accuracy of +/- 50 meters. The device must re-establish its position 
each time it is activated from a power-off condition. 
(3) (i) Fixed devices must access a TV bands database over the Internet to determine the TV 
channels that are available at their geographic coordinates prior to their initial service 
transmission at a given location. Operation is permitted only on channels that are indicated in the 

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database as being available for TVBDs. Fixed TVBDS shall access the database at least once a 
day to verify that the operating channels continue to remain available. Operation must cease 
immediately if the channel is no longer available. 
(ii) Mode II personal/portable devices must access a TV bands database over the Internet to 
determine the TV channels that are available at their geographic coordinates prior to their initial 
service transmission at a given location. Operation is permitted only on channels that are 
indicated in the database as being available for TVBDs. A Mode II personal/portable device must 
access the database for a list of available channels each time it is activated from a power-off 
condition and re-check its location and the database for available channels if it changes location 
during operation. A Mode II personal/portable device that has been in a powered state shall recheck 
its location and access the database daily to verify that the operating channel(s) continue to 
be available. 
(iii) If a fixed or mode II TVBD fails to contact the TV bands database during any given day, it 
may continue to operate until 11:59 PM of the following day at which time it must cease 
operations unless it has contacted the TV bands database during the intervening period. 
(iv) Personal/portable devices operating in Mode I shall obtain a list of channels on which they 
may operate from a master device. 
(4) All geographic coordinates shall be referenced to the North American Datum of 1983 (NAD 
83). 
(c) Spectrum sensing. 
(1) Detection threshold. 
(i) All fixed and personal/portable TVBDs must be capable of detecting ATSC digital 
TV, NTSC analog TV and wireless microphone signals using analog or digital 
modulation methods. The required detection thresholds are. 
(A) ATSC signals: -114 dBm, averaged over a 6 MHz bandwidth; 
(B) NTSC signals: -114 dBm, averaged over a 100 kHz bandwidth; 
(C) Wireless microphone signals: -114 dBm, averaged over a 200 kHz bandwidth. 
(ii) The detection thresholds are referenced to an omnidirectional receive antenna with a 
gain of 0 dBi. If a receive antenna with a minimum directional gain of less than 0 dBi is 
used, the detection threshold shall be reduced by the amount in dB that the minimum 
directional gain of the antenna is less than 0 dBi. Minimum directional gain shall be 
defined as the antenna gain in the direction and at the frequency that exhibits the least 
gain. Alternative approaches for the sensing antenna are permitted, e.g., electronically 
rotateable antennas, provided the applicant for equipment authorization can demonstrate 
that its sensing antenna provides at least the same performance as an omnidirectional 
antenna with 0 dBi gain. 
(2) Low power auxiliary device channel availability check time. A TVBD may start operating on 
a TV channel if no wireless microphone or other low power auxiliary device signals above the 
detection threshold are detected within a minimum time interval of 30 seconds. 
(3) TV channel availability check time. A TVBD is required to check for TV signals for a 
minimum time interval of 30 seconds. If a TV signal is detected on a channel indicated as 

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available for use by the database system, the device will provide a notice of that detection to the 
operator of the device and a means for the operator to optionally remove the channel from the 
devices list of available channels. 
(4) In-service monitoring. A TVBD must perform in-service monitoring of an operating channel 
a minimum of once every 60 seconds. There is no minimum channel availability check time for 
in-service monitoring. 
(5) Channel move time. After a wireless microphone or other low power auxiliary device signal 
is detected on a TVBD operating channel, all transmissions by the TVBD must cease within two 
seconds. 
(6) Personal/portable devices operating in the client mode shall identify to the fixed or Mode II 
personal/portable device those television channels on which it senses any signals above the 
detection threshold. The fixed or Mode II device shall respond in accordance with the provisions 
of this paragraph as if it had detected the signal itself. 
(7) TVBDs communicating either directly with one another or linked through a base station must 
share information on channel occupancy determined by sensing. If any device in a local area 
group or network determines that a channel is occupied, all other linked devices will also be 
required to respond in accordance with the provisions of this paragraph as if it had detected the 
signal itself. 
(d) A TVBD must incorporate the capability to display a list of identified available channels and its 
operating channels. 
(e) Fixed TVBDs shall transmit identifying information. The identification signal must conform to a 
standard established by a recognized industry standards setting organization. The identification signal 
shall carry sufficient information to identify the device and its geographic coordinates. 
(f) If a fixed TVBD device does not have a direct connection to the Internet and has not yet been 
initialized and registered with the TV bands database, consistent with Section 15.713, but can receive the 
transmissions of another fixed TVBD, the device needing initialization may transmit on either a channel 
that the other TVBD has transmitted on or on a channel which the other TVBD indicates is available for 
use to access the database to register its location and receive a list of channels that are available for it to 
use. Subsequently, the newly registered TVBD must only use the television channels that the database 
indicates are available for it to use. Such client fixed devices must re-contact their master device to review 
their list of available channels at least once every 60 seconds. A fixed device may not operate as a client 
to another fixed device. 
(g) A personal/portable TVBD operating in Mode I may only transmit upon receiving the transmissions of 
fixed or Mode II TVBD. A personal/portable device operating in Mode I may transmit on either an 
operating channel of the fixed or Mode II TVBD or on a channel the fixed or Mode II TVBD indicates is 
available for use. 
Section 15.712 Interference protection requirements. 
(a) Digital television stations, and digital and analog Class A TV, low power TV, TV translator and TV 
booster stations: 

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(1) Protected contour. TVBDs must protect digital and analog TV services within the contours 
shown in the following table. These contours are based on the R-6602 curves contained in 
Section 73.699 of this chapter. 
Protected contour 
Type of station Channel Contour 
(dBu) 
Propagation curve 
Low VHF (2-6) 47 F(50,50) 
Analog: Class A TV, LPTV, High VHF (7-13) 56 F(50,50) 
translator and booster UHF (14-69) 64 F(50,50) 
Low VHF (2-6) 28 F(50,90) 
Digital: Full service TV, Class A TV, High VHF (7-13) 36 F(50,90) 
LPTV, translator and booster UHF (14-51) 41 F(50,90) 
(2) Required separation distance. Fixed TVBDs and personal/portable TVBDs operating in Mode 
II must be located outside the contours indicated in paragraph (1) of this section of co-channel 
and adjacent channel stations by at least the minimum distances specified in the following table. 
Alternatively, Mode II personal/portable TVBDs may operate at closer separation distances, 
including inside the contour of adjacent channel stations, provided the power level is reduced as 
specified in Section 15.709(a)(2). 
Antenna Height of 
Unlicensed Device 
Required Separation (km) 
From Digital or Analog TV (Full Service or Low 
Power) Protected Contour 
Co-channel Adjacent Channel 
Less than 3 meters 6.0 km 0.1 km 
3  Less than 10 meters 8.0 km 0.1 km 
10  30 meters 14.4 km 0.74 km 
(b) Translator receive sites and cable headends: For translator receive sites and cable headends registered 
in the TV bands database, TVBDs may not operate within an arc of +/-30 degrees from a line between the 
registered translator or cable headend receive site and the TV station being received within a distance of 
80 km from the receive site for co-channel operation and 20 km for adjacent channel operation. Outside 
of this +/-30 degree arc, TVBDs may not operate within 8 km from the receive site for co-channel 
operation and 2 km from the receive site for adjacent channel operation. 
(c) Fixed Broadcast Auxiliary Service (BAS) Links: For permanent BAS receive sites appearing in the 
Commissions Universal Licensing System or temporary BAS receive sites registered in the TV bands 
database, TVBDs may not operate within an arc of +/-30 degrees from a line between the BAS receive 
site and its associated permanent transmitter within a distance of 80 km from the receive site for cochannel 
operation and 20 km for adjacent channel operation. Outside this +/-30 degree arc, TVBDs may 
not operate within 8 km from the receive site for co-channel operation and 2 km from the receive site for 
adjacent channel operation. 
(d) PLMRS/CMRS operations: TVBDs may not operate at distances less than 134 km for co-channel 
operations and 131 km for adjacent channel operations from the coordinates of the metropolitan areas and 
on the channels listed in Section 90.303(a) of this chapter. For PLMRS/CMRS operations outside of the 
metropolitan areas listed in Section 90.303(a) of this chapter, co-channel and adjacent channel TVBDs 
may not operate closer than 54 km and 51 km, respectively from a base station.

Federal Communications Commission FCC 08-260 
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(e) Offshore Radiotelephone Service: TVBDs may not operate on channels used by the Offshore Radio 
Service within the geographic areas specified in Section 74.709(e) of this chapter. 
(f) Low power auxiliary services, including wireless microphones: 
(1) TVBDs will not be permitted to operate within 1 km of the coordinates of registered wireless 
microphone sites during designated times when wireless microphones are used. 
(2) (A) TVBDs will not be permitted to operate within 134 km of the 13 metropolitan areas listed 
in Section 90.303(a) of this chapter. , 
(B) TVBDs will not be permitted to operate on the first available channel on each side of TV 
channel 37 (608-614 MHz) within 134 km of the 13 metropolitan areas listed in Section 90.303(a) 
of this chapter. If one or both of those channels are occupied by a licensed service in one or more 
of these metropolitan areas, operation of TVBDs is prohibited on the first channel adjacent to the 
occupied channel(s). 
(g) Border areas near Canada and Mexico: 
(1) Fixed and personal/portable TVBDs shall not operate within 32 kilometers of the Canadian 
Border. 
(2) Fixed and personal/portable TVBDs shall not operate within 40 kilometers of the Mexican 
border on UHF channels, or within 60 kilometers on VHF channels. 
(h) Radio astronomy services: Operation of fixed and personal/portable TVBDs is prohibited on all 
channels within 2.4 kilometers at the following locations. 
(1) The Naval Radio Research Observatory in Sugar Grove, West Virginia. 
(2) The Table Mountain Radio Receiving Zone (TMRZ) at 400750 N and 1051540 W. 
(3) The following facilities. 
Observatory Longitude 
(Deg/Min/Sec) 
Latitude 
(Deg/Min/Sec) 
Allen Telescope Array 121 28 24 W 40 49 04 N 
Arecibo Observatory 066 45 11 W 18 20 46 N 
Green Bank Telescope 
(GBT) 
079 50 24 W 38 25 59 N 
Very Large Array (VLA) 107 37 04 W 34 04 44 N 
Very Long Baseline Array 
(VLBA) Stations 
Pie Town, AZ 108 07 07 W 34 18 04 N 
Kitt Peak, AZ 111 36 42 W 31 57 22 N 
Los Alamos, NM 106 14 42 W 35 46 30 N 
Ft. Davis, TX 103 56 39 W 30 38 06 N 
N. Liberty, IA 091 34 26 W 41 46 17 N 
Brewster, WA 119 40 55 W 48 07 53 N 
Owens Valley, CA 118 16 34 W 37 13 54 N 
St. Croix, VI 064 35 03 W 17 45 31 N 
Hancock, NH 071 59 12 W 42 56 01 N

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Mauna Kea, HI 155 27 29 W 19 48 16 N 
Section 15.713 TV bands database. 
One or more entities will be designated to serve as database administrator. 
(a) Purpose. The TV bands database serves the following functions: 
(1) To determine and provide to a TVBD, upon request, the available TV channels at the TVBDs 
location. Available channels are determined based on the interference protection requirements in 
Section 15.712 of this part. 
(2) To register the identification information and location of fixed TVBDs. 
(3) To register protected locations and channels as specified in paragraph (b)(2) of this section, 
that are not otherwise recorded in Commission licensing databases. 
(b) Information in the TV bands database. 
(1) Facilities already recorded in Commission databases. Identifying and location information 
will come from the official Commission database. These services include: 
(A) Digital television stations 
(B) Digital and analog Class A television stations 
(C) Low power television stations 
(D) Television translator and booster stations 
(E) Broadcast Auxiliary Service stations (including receive only sites), except low power 
auxiliary stations 
(F) Private land mobile radio service stations 
(G) Commercial mobile radio service stations 
(H) Offshore radiotelephone service stations 
(2) Facilities that are not recorded in Commission databases. Identifying and location 
information will be entered into the TV bands database in accordance with the procedures 
established by the TV bands database administrator(s). These include: 
(A) Cable television headends 
(B) Television translator station receive sites 
(C) Sites where low power auxiliary stations, including wireless microphones and 
wireless assist video devices, are used and their schedule for operation 
(D) Fixed TVBDs 
(c) Restrictions on registration. 
(1) Television translator station receive sites within the protected contour of the station being 
received are not eligible for registration in the database. 
(2) Cable television headends within the protected contour of a television channel are not eligible 
to register that channel in the database. 
(d) Determination of available channels. 

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(1) The TV bands database will determine the available channels at a location using the 
interference protection requirements of section 15.712 of this part, the location information 
supplied by a TVBD, and the data for protected stations/locations in the database. The TV bands 
database will also check for proximity of a TVBD to the Canadian and Mexican borders where 
operation may be prohibited pursuant to Section 15.712(g) of this chapter. 
(e) TVBD initialization. 
(1) Fixed and Mode II TVBDs must provide their location and required identifying information to 
the TV bands database in accordance with the provisions of paragraph (b) of this section. 
(2) Fixed and Mode II TVBDs shall not transmit unless they receive, from the TV bands 
database, a list of available channels. 
(3) Fixed TVBDs register and receive a list of available channels by either connecting directly to 
the internet or by receiving information from another fixed TVBD. 
(4) Mode II TVBDs register and receive a list of available channels by connecting directly to the 
internet. 
(f) Fixed TVBD registration. 
(1) Prior to operating for the first time or after changing location, a fixed TVBD must register 
with the TV bands database by providing the information listed in (c)(3) of this paragraph. 
(2) The party responsible for a Fixed TVBD must ensure that the TVBD registration database has 
the most current, up-to-date information for that device. 
(3) The TVBD registration database shall contain the following information for fixed TVBDs: 
(A) FCC identifier (FCC ID) of the device 
(B) manufacturers serial number of the device 
(C) devices geographic coordinates (latitude and longitude (NAD 83) accurate to 
+/- 50 m) 
(D) name of the individual or business that owns for the device 
(E) name of a contact person responsible for the devices operation 
(F) address for the contact person 
(G) email address for the contact person 
(H) phone number for the contact person. 
(g) A personal/portable device operating in Mode II shall provide the database its FCC Identifier (as 
required by Section 2.926 of this chapter), serial number as assigned by the manufacturer, and the 
devices geographic coordinates (latitude and longitude (NAD 83) accurate to +/- 50 m) 
(h) The TV bands database shall contain the listed information for each of the following: 
(1) Digital television stations, digital and analog Class A, low power, translator and booster 
stations:
(A) transmitter coordinates (latitude and longitude in NAD 83) 
(B) Effective radiated power (ERP) 
(C) height above average terrain of the transmitter (HAAT)

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(D) horizontal transmit antenna pattern (if the antenna is directional) 
(E) channel number 
(F) station call sign 
(2) Broadcast Auxiliary Service. 
(A) transmitter coordinates (latitude and longitude in NAD 83) 
(B) receiver coordinates (latitude and longitude in NAD 83) 
(C) channel number 
(D) call sign 
(3) Metropolitan areas listed in section 90.303(a) of this chapter. 
(A) region name 
(B) channel(s) reserved for use in the region 
(C) geographic center of the region (latitude and longitude in NAD 83) 
(D) call sign 
(4) PLMRS/CMRS base station operations located more than 80 km from the geographic centers 
of the 13 metropolitan areas defined in section 90.303(a) of this chapter (e.g., in accordance with 
a waiver). 
(A) transmitter location (latitude and longitude in NAD 83) or geographic area of 
operations 
(B) Effective radiated power 
(C) transmitter height above average terrain (if specified) 
(D) antenna height above ground level (if specified) 
(E) call sign 
(5) Offshore Radiotelephone Service. For each of the four regions where the Offshore 
Radiotelephone Service operates. 
(A) geographic boundaries of the region (latitude and longitude in NAD 83 for each point 
defining the boundary of the region 
(B) channel(s) used by the service in that region 
(6) Cable Television headends. 
(A) name and address of cable company 
(B) location of the headend receiver (latitude and longitude in NAD 83, accurate to 
+/- 50 m) 
(C) channel number of each television channel received, subject to the following 
condition: channels for which the cable headend is located within the protected contour 
of that channels transmitting station are not eligible for registration in the database 
(D) call sign of each television channel received and eligible for registration 
(E) location (latitude and longitude) of the transmitter of each television channel received 
(7) Television translator and low power TV, including Class A TV stations, receive sites. 
(A) call sign of the TV translator station 
(B) location of the TV translator receive site (latitude and longitude in NAD 83, accurate 
to +/- 50 m)

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(C) channel number of the retransmitted television station, subject to the following 
condition: a channel for which the television translator receive site is located within the 
protected contour of that channels transmitting station is not eligible for registration in 
the database 
(D) call sign of the retransmitted television station 
(E) location (latitude and longitude) of the transmitter of the retransmitted television 
station 
(8) Low power auxiliary stations, including wireless microphones and wireless assist video 
devices. Sites with significant wireless microphone use at well defined times and locations may 
be registered in the database. Multiple registrations that specify more than one point in the facility 
may be entered for very large sites. Registrations will be valid for no more than one year, after 
which they may be renewed. 
(A) name of the individual or business that owns the low power auxiliary device(s) 
(B) an address for the contact person 
(C) an email address for the contact person (optional) 
(D) a phone number for the contact person 
(E) coordinates where the device(s) are used (latitude and longitude in NAD 83, accurate 
to +/- 50 m) 
(F) channels used by the low power auxiliary devices operated at the site 
(G) specific months, days and times when the device(s) are used. 
(h) Commission requests for data. 
(1) A TV bands database administrator must supply upon request by the Commission, any 
information contained in the database. 
(2) A TV bands database administrator must remove information from the database, upon 
direction, in writing, by the Commission 
Section 15.714 TV bands database administration fees. 
(a) A TV bands database administrator may charge a fee for provision of lists of available channels and 
for registering Fixed TVBDs and temporary BAS links. 
(b) The Commission, upon request, will review the fees and can require changes in those fees if they are 
found to be excessive. 
Section 15.715 TV bands database administrator. 
The Commission will designate one or more entities to administer a TV bands database. Each database 
administrator shall: 
(a) Maintain a database that contains the information described in Section 15.713 of this part. 
(b) Establish a process for downloading and storing in the database necessary and appropriate 
information from the Commissions databases and synchronizing the TV bands database with the 
current Commission databases at least once a week to include newly licensed facilities or any 
changes to licensed facilities.

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(c) Establish a process for registering Fixed TVBDs and registering and including in the database 
facilities entitled to protection but not contained in a Commission database, including cable 
headends and TV translator receiver sites. 
(d) Establish a process for registering facilities where Part 74 low power auxiliary devices are 
used on a regular basis. 
(e) Provide lists of available channels to Fixed and personal/portable TVBDs that submit to it the 
information required under Section 15.713(f) based on their geographic location. 
(f) Make its services available to all unlicensed TV band device users on a non-discriminatory 
basis. 
(g) Provide service for a five-year term. This term can be renewed at the Commissions 
discretion. 
(h) Respond in a timely manner to verify, correct and/or remove, as appropriate, data in the event 
that the Commission or a party brings claim of inaccuracies in the database to its attention. 
(i) Transfer its database along with the IP addresses and URLs used to access the database and list 
of registered Fixed TVBDs, to another designated entity in the event it does not continue as the 
database administrator at the end of its term. It may charge a reasonable price for such 
conveyance. 
(j) The database must have functionality such that upon request from the Commission it can 
indicate that no channels are available when queried by a specific TVBD or model of TVBDs. 
(k) If more than one database is developed, the database administrators must cooperate to develop 
a standardized process for providing on a daily basis or more often, the data collected for the 
facilities listed in section 15.713(b)(2) of this part to all other TV bands databases. 
Section 15.717 TVBDs that rely on spectrum sensing. 
(a) Parties may submit applications for certification of TVBDs that rely solely on spectrum sensing to 
identify available channels. Devices authorized under this section must demonstrate with an extremely 
high degree of confidence that they will not cause harmful interference to incumbent radio services. 
(1) In addition to the procedures in Subpart J of Part 2 of this chapter, applicants shall comply with the 
following. 
(i) The application must include a full explanation of how the device will protect incumbent 
authorized services against interference. 
(ii) Applicants must submit a pre-production device, identical to the device expected to be 
marketed. 
(2) The Commission will follow the procedures below for processing applications pursuant to this section. 
(i) Applications will be placed on Public Notice for a minimum of 30 days for comments and 15 
days for reply comments. Applicants may request that portions of their application remain 
confidential in accordance with section 0.459 of this chapter. This Public Notice will include 
proposed test procedures and methodologies. 

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(ii) The Commission will conduct laboratory and field tests of the pre-production device. This 
testing will be conducted to evaluate proof of performance of the device, including 
characterization of its sensing capability and its interference potential. The testing will be open to 
the public. 
(iii) Subsequent to the completion of testing, the Commission will issue by Public Notice, a test 
report including recommendations. The Public Notice will specify a minimum of 30 days for 
comments and, if any objections are received, an additional 15 days for reply comments. 
(b) The device shall meet the requirements for personal/portable devices in this subpart except that it will 
be limited to a maximum EIRP of 50 mw and it does not have to comply with the requirements for geolocation 
and database access in Section 15.711(b). Compliance with the detection threshold for spectrum 
sensing in Section 15.711(c), although required, is not necessarily sufficient for demonstrating reliable 
interference avoidance. Once a device is certified, additional devices that are identical in electrical 
characteristics and antenna systems may be certified under the procedures of Part 2, Subpart J of this 
chapter.

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APPENDIX C 
Final Regulatory Flexibility Analysis 
As required by the Regulatory Flexibility Act (RFA),343 an Initial Regulatory Flexibility Analysis 
(IRFA) was incorporated in the Notice of Propose Rule Making (NPRM) in ET Docket No. 04-186344 and 
an additional IRFA was incorporated in the First Report and Order and Further Notice of Proposed Rule 
Making (Further Notice) in ET Docket No. 04-186.345 The Commission sought written public comment 
on the proposals in the NPRM and in the Further Notice, including comment on the IRFAs. No 
comments were received in response to either IRFA. This Final Regulatory Flexibility Analysis (FRFA) 
conforms to the RFA.346 
A. Need for, and Objectives of, the Second Report and Order 
This Second Report and Order allows low power unlicensed transmitters to operate in the TV 
broadcast bands at locations where spectrum is not being used by authorized services. The new rules 
provide for operation of two types of unlicensed devices that may provide broadband data and other types 
of communications services: 1) fixed devices, which will operate from a fixed location with relatively 
higher power and could be used to provide a variety of services including wireless broadband access in 
urban and rural areas, and 2) personal/portable devices, which will use lower power and could, for 
example, take the form of devices such as Wi-Fi-like cards in laptop computers or wireless in-home local 
area networks (LANs). In order to operate without causing interference to licensed services, both types of 
devices will be required to be able to reliably determine which channels are occupied by licensed 
operations at their location at any given time and to avoid interfering with services on those channels. 
The specific compliance requirements are described in Section D below. 
The actions in this Second Report and Order will open for use a significant amount of spectrum 
with very desirable propagation characteristics that has heretofore lain fallow. These new rules will allow 
the development of new and innovative types of unlicensed devices that provide broadband data and other 
services for businesses and consumers without disrupting the incumbent television and other authorized 
services that operate in the TV bands. In addition, because transmissions on frequencies in the TV bands 
are less subject to propagation losses than transmissions in the spectrum bands where existing low power 
broadband unlicensed operations are permitted, i.e., the 2.4 GHz and 5 GHz bands, the Commission 
anticipates that allowing unlicensed operation in the TV bands will benefit wireless internet service 
providers (WISPs) by extending the service range of their operations. This will allow wireless broadband 
providers that use unlicensed devices to reach new customers and to extend and improve their services in 
rural areas. The Commission anticipates that allowing use of the TV white spaces by unlicensed devices 
will have significant benefits for both businesses and consumers and thereby promote more efficient and 
effective use of the TV spectrum. 
B. Summary of Significant Issues Raised by Public Comments in Response to the IRFA 
No comments were received in response to either the IRFA in the NPRM or the IRFA in the 
Further Notice. 
343 See 5 U.S.C.  603. The RFA, see 5 U.S.C.  601-612, has been amended by the Small Business Regulatory 
Enforcement Fairness Act of 1996 (SBREFA), Pub. L. No. 104-121, Title II, 110 Stat. 857 (1996). 
344 NPRM, 19 FCC Rcd at 10018. 
345 Further Notice, 21 FCC Rcd at 12299. 
346 See 5 U.S.C. 603, Title II, 110 Stat 857 (1996).

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C. Description and Estimate of the Number of Small Entities To Which Rules Will Apply 
The RFA directs agencies to provide a description of, and, where feasible, an estimate of, the 
number of small entities that may be affected by the rules adopted herein.347 The RFA generally defines 
the term small entity as having the same meaning as the terms small business, small organization, 
and small governmental jurisdiction.348 In addition, the term small business has the same meaning as 
the term small business concern under the Small Business Act.349 A small business concern is one 
which: (1) is independently owned and operated; (2) is not dominant in its field of operation; and (3) 
satisfies any additional criteria established by the Small Business Administration (SBA).350 
Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing. 
The Census Bureau defines this category as follows: This industry comprises establishments primarily 
engaged in manufacturing radio and television broadcast and wireless communications equipment. 
Examples of products made by these establishments are: transmitting and receiving antennas, cable 
television equipment, GPS equipment, pagers, cellular phones, mobile communications equipment, and 
radio and television studio and broadcasting equipment.351 The SBA has developed a small business 
size standard for Radio and Television Broadcasting and Wireless Communications Equipment 
Manufacturing, which is: all such firms having 750 or fewer employees.352 According to Census 
Bureau data for 2002, there were a total of 1,041 establishments in this category that operated for the 
entire year.353 Of this total, 1,010 had employment of under 500, and an additional 13 had employment 
of 500 to 999.354 Thus, under this size standard, the majority of firms can be considered small. 
Wireless Service Providers. The SBA has developed a small business size standard for wireless 
firms within the two broad economic census categories of "Paging"355 and "Cellular and Other Wireless 
Telecommunications."356 Under both categories, the SBA deems a wireless business to be small if it has 
347 5 U.S.C.  604(a)(3). 
348 5 U.S.C.  601(6). 
349 5 U.S.C.  601(3) (incorporating by reference the definition of small-business concern in the Small Business 
Act, 15 U.S.C.  632). Pursuant to 5 U.S.C.  601(3), the statutory definition of a small business applies unless an 
agency, after consultation with the Office of Advocacy of the Small Business Administration and after opportunity 
for public comment, establishes one or more definitions of such term which are appropriate to the activities of the 
agency and publishes such definition(s) in the Federal Register. 
350 15 U.S.C.  632. 
351 U.S. Census Bureau, 2002 NAICS Definitions, 334220 Radio and Television Broadcasting and Wireless 
Communications Equipment Manufacturing; http://www.census.gov/epcd/naics02/def/NDEF334.HTM#N3342. 
352 13 C.F.R.  121.201, NAICS code 334220. 
353 U.S. Census Bureau, American FactFinder, 2002 Economic Census, Industry Series, Industry Statistics by 
Employment Size, NAICS code 334220 (released May 26, 2005); http://factfinder.census.gov. The number of 
establishments is a less helpful indicator of small business prevalence in this context than would be the number of 
firms or companies, because the latter take into account the concept of common ownership or control. Any 
single physical location for an entity is an establishment, even though that location may be owned by a different 
establishment. Thus, the numbers given may reflect inflated numbers of businesses in this category, including the 
numbers of small businesses. In this category, the Census breaks-out data for firms or companies only to give the 
total number of such entities for 2002, which was 929. 
354 Id. An additional 18 establishments had employment of 1,000 or more. 
355 13 C.F.R.  121.201, NAICS code 517211. 
356 13 C.F.R.  121.201, NAICS code 517212.

Federal Communications Commission FCC 08-260 
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1,500 or fewer employees. For the census category of Paging, Census Bureau data for 2002 show that 
there were 807 firms in this category that operated for the entire year.357 Of this total, 804 firms had 
employment of 999 or fewer employees, and three firms had employment of 1,000 employees or more.358 
Thus, under this category and associated small business size standard, the majority of firms can be 
considered small. For the census category of Cellular and Other Wireless Telecommunications, Census 
Bureau data for 2002 show that there were 1,397 firms in this category that operated for the entire year.359 
Of this total, 1,378 firms had employment of 999 or fewer employees, and 19 firms had employment of 
1,000 employees or more.360 Thus, under this second category and size standard, the majority of firms 
can, again, be considered small. 
D. Description of Projected Reporting, Record Keeping, and Other Compliance Requirements 
Unlicensed transmitters are currently required to be authorized under the Commission's 
certification procedure as a prerequisite to marketing and importation, and TV band devices would be 
subject to a certification requirement. The existing certification procedure in the Commissions rules will 
be used for TV band devices, except that TV band devices that rely on spectrum sensing as the sole 
method of determining whether a channel is available will have additional certification requirements 
which are described below. The compliance requirements for TV band devices are as follows. 
Fixed devices 
 may communicate with other fixed devices and with personal/portable devices 
 are permitted to operate on TV channels 2-51, excluding channels 3,4 and 37; may not operate on 
adjacent TV channels; and, must not use any channels used locally by the private land mobile 
radio service (PLMRS) 
 determine their geographic location by means of an incorporated geo-location capability or a 
professional installer 
 access a database system to determine the available channels at a location 
 use outdoor antennas 
 are allowed up to 1 watt (W) transmitter output power with a gain antenna to achieve up to 4 W 
effective isotropic radiated power (EIRP) 
 Must register identifying information in a database to help investigate any potential interference 
due to higher powered operations. 
Personal/portable devices 
 may communicate with fixed devices and with other personal/portable devices 
357 U.S. Census Bureau, 2002 Economic Census, Subject Series: Information, Establishment and Firm Size 
(Including Legal Form of Organization, Table 5, NAICS code 517211 (issued Nov. 2005). 
358 Id. The census data do not provide a more precise estimate of the number of firms that have employment of 
1,500 or fewer employees; the largest category provided is for firms with 1000 employees or more. 
359 U.S. Census Bureau, 2002 Economic Census, Subject Series: Information, Establishment and Firm Size 
(Including Legal Form of Organization, Table 5, NAICS code 517212 (issued Nov. 2005). 
360 Id. The census data do not provide a more precise estimate of the number of firms that have employment of 
1,500 or fewer employees; the largest category provided is for firms with 1000 employees or more.

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 are permitted to operate on TV channels 21-51, excluding channel 37 
 can operate in two different modes: 
o Mode I - client, controlled by a fixed device that has determined the available channels in 
the area 
o Mode II - independent, in which the device determines the available channels using its 
own internal geo-location/database access capabilities 
 100 milliwatts (mW) EIRP, but limited to 40 mW EIRP when operating adjacent to occupied 
channels. 
All TV band devices 
 must be capable of sensing TV and wireless microphone signals at levels as low as -114 dBm 
o Operation prohibited on channels where wireless microphones are detected 
o Will provide an additional indication as to whether a TV channel is occupied 
o Will encourage the further development of sensing technology 
The purpose of the TV bands database system for fixed and Mode II personal/portable devices is 
to identify all services in the TV bands that are eligible for protection. A TV band device will send its 
geographic coordinates to the database, which will return a list of channels available at that location. The 
Commission will issue a Public Notice to solicit interested parties in administering the database. The 
database will contain information about licensed services operating in the TV bands obtained from the 
Commissions databases, including full service and low power TV stations, Broadcast Auxiliary Service 
(BAS) links, and PLMRS operations under waivers. In addition, the database will contain voluntarily 
submitted information on services in the TV bands that are either not in the Commissions databases or 
are not licensed by specific coordinates, such as wireless microphones. 
The Second Report and Order provides for certification of devices that rely on sensing alone 
based on a proof of performance standard. The manufacturer may submit an application for certification 
of a device that meets all of the requirements for a TV band device except for geo-location and database 
access. The application would be available to the public, except for information that may qualify as a 
trade secret under our rules. A fully functioning pre-production prototype would need to be submitted to 
the Commission for laboratory and field testing. The testing will be open to the public. The 
determination of whether to certify the equipment will depend on whether the device is shown to provide 
a high level of confidence that it will not interfere with incumbent radio services. It must perform at least 
as well as a device that uses geo-location and database access for interference avoidance. Once a device 
is certified under these provisions, the Commission would certify other devices that are electrically 
identical under the usual certification process. 
The Second Report and Order imposes new reporting requirements on parties operating fixed TV 
band devices. Operators of fixed TV band devices will be required to register their location and 
information about the operator with a TV bands database. When a fixed TV band device queries the 
database the first time, the device will be registered in the database system. Operators of fixed TV band 
devices must supply the following registration information and update this information, as necessary, 
when performing the daily database queries to verify continued channel availability. The Commission 
may ask a database administrator for this information in the event that a device is found to be causing 
interference. 
(1) FCC identifier (FCC ID) of the device 
(2) manufacturers serial number of the device

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(3) devices coordinates (latitude and longitude accurate to within 50 m) 
(4) name of the entity, whether an individual or business, responsible for the device 
(5) name of a contact person responsible for the devices operation 
(6) address for the contact person 
(7) email address for the contact person 
(8) phone number for the contact person. 
As noted above, the Commissions Office of Engineering and Technology will designate a party 
or parties to administer the database of authorized services in the TV bands. Much of this information 
will be obtained from the Commissions databases, including information on full service and low power 
TV stations, Broadcast Auxiliary Service (BAS) links, and PLMRS operations under waivers. However, 
the database will also contain information submitted voluntarily by parties operating services in the TV 
bands that are either not listed in the Commissions databases or are not licensed by specific coordinates. 
These services include BAS links authorized on a temporary basis, receive sites for TV translators and 
cable TV systems, and sites where wireless microphones are used regularly and predictably, such as 
major sporting events. The purpose of this voluntarily submitted information is to prevent TV band 
devices from causing interference to services that do not appear in the Commissions database. The 
submission of such information is strictly voluntary, but services operated by parties that do not submit 
this information may not be protected against interference from TV band devices. 
E. Steps Taken to Minimize Significant Economic Impact on Small Entities and Significant 
Alternatives Considered 
The RFA requires an agency to describe any significant alternatives that it has considered in developing 
its approach, which may include the following four alternatives (among others): (1) the establishment of 
differing compliance or reporting requirements or timetables that take into account the resources available 
to small entities; (2) the clarification, consolidation, or simplification of compliance and reporting 
requirements under the rule for such small entities; (3) the use of performance rather than design 
standards; and (4) an exemption from coverage of the rule, or any part thereof, for such small entities.361 
The rules adopted in the Second Report and Order may have a significant economic impact on a 
substantial number of small entities. For an entity that chooses to manufacture or import equipment for 
the subject bands, the rules would impose costs for compliance with equipment technical requirements. 
The costs for fixed and Mode II personal/portable devices include incorporating a geo-location method to 
determine the geographic coordinates and the ability to access a database of authorized services in the TV 
bands, for which a fee may be charged by the database administrator. The costs for all TV band devices 
include incorporating the ability to detect TV and wireless microphone signals. However, the burdens for 
complying with these rules would be the same for both large and small entities. Therefore, no 
disproportionate burden of compliance would be sustained by small entities. Further, the rules adopted in 
the Second Report and Order are ultimately beneficial for both large and small entities because they will 
provide for more efficient and effective use of the TV spectrum and allow the development of new and 
innovative types of wireless devices and communication services for businesses and consumers. Also, 
because transmissions in the TV band are subject to less propagation attenuation than transmissions in 
other bands where lower power operations are permitted (such as unlicensed operations in the 2.4 GHz 
band), operations in the TV bands can improve the service range of wireless operations, thereby allowing 
operators to reach new customers. 
361 5 U.S.C.  603(c)(1)  (c)(4).

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F. Report to Congress 
The Commission will send a copy of the Second Report and Order, including this FRFA, in a 
report to be sent to Congress pursuant to the Congressional Review Act.362 In addition, the Commission 
will send a copy of the second Report and Order, including the FRFA, to Congress and the Government 
Accountability Office. A copy of the Second Report and Order and FRFA (or summaries thereof) will 
also be published in the Federal Register.363 
362 See 5 U.S.C.  801(a)(1)(A). 
363 See 5 U.S.C.  604(b).

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STATEMENT OF 
CHAIRMAN KEVIN J. MARTIN 
Re: Unlicensed Operation in the TV Broadcast Bands, ET Docket No. 04-186; Additional Spectrum for 
Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380 
Todays approval of rules authorizing the use of television (TV) white spaces spectrum is a significant 
victory for consumers. 
Todays action was advocated by a diverse coalition of consumer groups, technology leaders and Internet 
pioneers. Opening the white spaces will allow for the creation of a WiFi on steroids. It has the potential 
to improve wireless broadband connectivity and inspire an ever-widening array of new Internet based 
products and services for consumers. Consumers across the country will have access to devices and 
services that they may have only dreamed about before. I fully expect that everything from enhanced 
home broadband networks, to intelligent peer-to-peer devices, and even small communications networks 
will come into being in TV white spaces. 
More specifically, the rules adopted by the Commission establish a framework for enhanced wireless 
communications by building on a proven concept: the safe deployment of new, intelligent devices in the 
unused spectrum that exists between television channels. 
We do so without disrupting TV services, wireless microphones, or other permitted uses of this spectrum. 
I have always said that opening the white spaces must be conditioned on protecting primary spectrum 
users from interference. 
We have been cautious in our approach. Significantly, the Commission embarked on extraordinary 
testing. Not only did the Commission consider thousands of comments, ideas and recommendations 
submitted by the public, we opened up the testing of the prototype white spaces devices that had been 
submitted to the FCC. For months, both proponents and opponents of opening the white spaces 
participated in laboratory and field testing conducted by our engineers. OET also released a lengthy and 
detailed report of its findings to the public. 
Normally, the Commission adopts prospective rules about interference and then certifies devices to ensure 
they are in compliance. Here, we took the extraordinary step of first conducting this extensive 
interference testing in order to prove the concept that white space devices could be safely deployed. 
Prior to going to market any white space device will undergo a rigorous certification process. Todays 
item protects broadcasters operations. It also protects entertainment, sports and other significant venues, 
including the unlicensed operation of many wireless microphones and other wireless devices in those 
areas. Additionally, channels have even been set aside to protect wireless microphones in major markets. 
In order to protect broadcasters, all white space devices must initially use geo-location in conjunction 
with database consultation to ensure they can operate in a particular location without interference. 
Manufacturers remain free to demonstrate that sensing-only devices can operate safely and efficiently, 
without causing interference to television viewers. Such devices will only be deployed after they have 
demonstrated their effectiveness through a vigorous, public, proof of performance process. 
Similarly, manufacturers are challenged to show ways that devices using higher power levels that 
authorized today can be deployed on adjacent channels. 

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In conjunction with our other actions today regarding Verizon-Alltel and Sprint-Clearwire, opening up the 
TV white spaces furthers the goal of making wireless a powerful, competitive broadband platform and 
offers significant benefits to consumers across the country. 

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STATEMENT OF 
COMMISSIONER MICHAEL J. COPPS 
Re: Unlicensed Operation in the TV Broadcast Bands, ET Docket No. 04-186; Additional Spectrum for 
Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380 
One of the great lessons of history I quickly learned here at the FCC is the power of technology to 
turn scarcity into abundance. Once upon a time, it seemed that certain swaths of the public airwaves 
could support only a few expensive, bulky brick telephones (so named because of their forbidding size 
and weight). These early phones permitted just 30 minutes of scratchy voice communications on a single 
battery charge. Today, thanks to the extraordinary work of Americas great engineers and inventors, the 
same amount of spectrum can support millions of full-featured, relatively inexpensive, multimedia 
handsetslike the popular iPhonethat perform many of the functions of a desktop computer for days 
between charges. 
Or, to take an example even closer to todays item, we have learned in the past decade that 
unlicensed bandsonce derided as junk spectrum suitable only for garage door openerscan actually 
support Wi-Fi connectivity for tens and even hundreds of millions of users every day. Something that 
seemed of marginal value has given us broadband in homes, airports, hotels, coffee shops, and downtown 
areasdevelopments that are changing the ways in which we live. Just stop by a Starbucks and look at 
how many people are typing away on laptops. That, to me, is the most important lesson of the wireless 
revolution: as technology marches on, the real winners are American consumers. This process is as it 
should bethe airwaves, after all, are the peoples airwaves. And it is the FCCs job to make sure that 
the American people continue to extract full value from their property. 
So in setting responsible spectrum policy, the FCC must always recognize that technology cannot 
stand still, and that even as we protect existing users from harmful interference, we also have to promote 
innovationbecause until someone finds a way to make more electromagnetic spectrum, it is only 
innovation that can improve the wireless choices available to consumers. 
For four years, the FCC has been considering proposals to authorize unlicensed devices in the TV 
white spaces. The proponents have argued that we can enable a whole new generation of wireless 
devicesbringing new broadband connectivity to our rural and urban communitieswithout harming 
free, over-the-air TV. Does this seem almost too good to be true? Of course. But so did the modern 
cellular industry, the explosion of Wi-Fi devices, and so many other innovations at comparable stages in 
their development. Even the notion of transmitting high quality video through the air to millions of TV 
sets must have seemed pretty fantastical when it was first demonstrated decades ago. This is the history 
of wireless innovation in a nutshellthe nearly miraculous becomes commonplace. 
My approach throughout this process has been to let the engineering analysis drive our decisionmaking. 
The good news is that the processwhile far from perfecthas involved a great deal of serious 
study and public openness. In fact, the last round of testing was conducted with engineers and lawyers 
from all sides looking over the shoulders of the FCCs engineers as they performed their bench and field 
testing. While I do not envy the Commissions engineers for undergoing this level of scrutiny as they go 
about their daily tasks, I think its fair to say that few other engineering analyses at the FCC have been as 
lengthy or open as this one. 
The results of our testing have shown that there is merit in the initial positions of both sides in this 
debateand I believe our conclusion today reflects this point. For example, the white spaces proponents 
initially argued that spectrum-sensing alone would be adequate. Our testing has shown that this approach, 
right now, is not ready for prime time. That is why our decision does not authorize devices today that rely 

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exclusively on sensingthough we do create a process for evaluating the next generation of such 
devices. 
Instead, today, we move towards a compromise technologygeo-locationthat represents a 
simpler and more conservative approach to protecting existing licensed users of the television band. We 
also have built in several forms of belt-and-suspender protections. First, we still will have a chance to 
kick the tires of these devices at the certification stageto make sure they operate as designed. 
Second, because we permit these devices to operate under our Part 15 unlicensed rules, they must protect 
broadcast licensees and shut off if they create harmful interference. Third, because we use geo-location 
technology, we retain the ability to require particular makes and models of white space devices to turn off 
if they have a manufacturing flaw. Fourth, to the extent that we consider certifying a next-generation 
sensing-only device, we have established a process to make sure that all parties have an opportunity to be 
present during the testing process. So, though there will never be metaphysical certainty when it comes to 
interference issues, I am comfortable that the FCC and its dedicated engineers have approached this issue 
with the necessary seriousness and developed an approach that will adequately protect over-the-air 
viewers. 
In this lengthy process, some parties have come forward with arguments for licensed use of the 
TV white spaces, either in whole or in part. As I have stated before, I think that both licensed and 
unlicensed regimes benefit consumers. The key is to get the right mix. In the past few years, we have 
auctioned off almost 150 MHz of new licensed spectrum. The time has now come, I believe, to increase 
the amount of unlicensed spectrumespecially the amount of spectrum below 1 GHz. The order we vote 
on today will do exactly that. 
Some have called this new technology Wi-Fi on steroidsand I hope they are right. Certainly, 
this new technology, taking advantage of the enhanced propagation characteristics of TV spectrum, 
should be of enormous benefit in solving the broadband deficit in many rural areas. Indeed, I agree with 
the view of several of my colleagues that it should be quite possible, at some point, to authorize higherpower 
devices in rural areas that will support backhaul and broadband infrastructure. That is why I 
support our commitment to issue a Notice of Inquiry on this topicwhich should give the Commission 
more than enough time to build a record and act before the first commercially-ready devices enter the 
market. 
Todays item represents the culmination of a lot of hard work by the Commissions skilled 
engineers and staff in our Office of Engineering and Technology and elsewhere. I want to thank them for 
their dedication to this task and their accomplishment in charting a course that accommodates both 
existing users and innovators in this spectrum. Ultimately, this careful threading of the needle between 
the path-breaking and the tried-and-true will reap huge benefits for the American people.

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STATEMENT OF 
COMMISSIONER JONATHAN S. ADELSTEIN 
Re: Unlicensed Operation in the TV Broadcast Bands, ET Docket No. 04-186; Additional Spectrum for 
Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380 
Today the Commission takes a critically important step towards managing the publics spectrum to 
promote efficiency, and to encourage the development and availability of innovative devices and services. 
White spaces are the blank pages on which we will write our broadband future. I have long called 
for not only a third pipe into the home but a third channel directly to consumers, wherever they may 
roam. Today, we make a key advance toward a third channel for broadband competition and deployment. 
This Order is a central element of the national broadband strategy that I have advocated for quite some time. 
Todays decision is consequential to our nations future because wireless broadband has the 
potential to improve our economy and quality of life in even the remotest areas. One of the best options 
for promoting broadband and competition across the country, particularly in rural areas, is maximizing the 
potential of spectrum-based services. Because we are a nation of innovators and entrepreneurs, the 
Commissions decision to open fallow spectrum to new uses will give our country an opportunity to 
reclaim its place as a world leader in broadband deployment. 
Wireless devices have become a central part of many of our lives. As the market continues to 
expand, so too does our need for spectrum and infrastructure that can meet the rising demands. Our job 
as a Commission is to pack as much data as possible over the public spectrum without causing harmful 
interference. Unlicensed spectrum holds by far the most promise for maximizing the use of white spaces. 
Our balanced approach in this order provides the flexibility and low barriers to entry needed to provide an 
opportunity for everyone to make the best use of this under-used spectrum. It also implements safeguards 
to protect those that already make valuable use of the spectrum. 
The results of the Office of Engineering and Technologys study show that geo-location 
technology offers an accurate and dependable means of protecting spectrum incumbents from 
interference. I am pleased with our decision to require both master-client based and independent based 
devices to utilize geo-location technology and database access for identifying vacant channels. Because 
broadcasters have such a vital role in local communities, preservation of consumers television reception 
and other services is critical to acceptance of new white spaces devices. Although spectrum-sensing 
technology has not yet been proven to offer the same level of protection, I applaud our support for its 
continuing development and look forward to the innovation it may bring. 
I am pleased that my colleagues have agreed to provide details regarding the certification process 
for white space devices. These additional details will provide an avenue for public comment on this 
process and ensure that the resulting process is fully vetted by interested parties. 
Many have raised the concern that broadcasters and users of wireless microphones will suffer 
harmful interference as a result of this Order. The Office of Engineering and Technology assures us that 
there are adequate protections here to prevent harmful interference to licensed users, and I accept their 
assurances. 
It is small consolation to those that feel justifiably aggrieved by the process that there was 
overwhelming support for acting now, and that more time was unlikely to change the outcome. This 
process is not a model of transparency. When the Commission puts expediency ahead of an open process, 
it creates unnecessary resentment from parties that believe they were not given a fair hearing. This is not 

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the process I would have undertaken, but since our independent engineering staff justifies the decision on 
the basis of their best expert analysis, I approve this item. 
An issue of great concern remains, though, that many unwary consumers purchased wireless 
microphones that may not comport with Commission rules. An investigation is underway, and if we find 
that Commission rules were violated, we must act to protect the many musicians, performers and others 
who will need to ensure their equipment continues to work. While I am hopeful the protections we adopt 
today are sufficient, we will need to closely follow the impact on users of wireless microphones, and 
devise solutions, considering all spectrum at our disposal, so they can continue to use them with 
confidence they will function as they have come to expect. 
I am pleased that the Chairman and my colleagues have agreed to launch a separate Notice of 
Inquiry (NOI) into the best use of the white space spectrum for higher powered unlicensed operations in 
rural areas. In order for the white spaces to achieve maximum utilization in rural areas, rural wireless 
Internet service providers will need cheap, available and reliable backhaul. We need to explore all ways 
of achieving this. Variable power limits deserve our consideration as one possible means. I would have 
preferred that these questions were raised in a Notice of Proposed Rulemaking rather than an NOI, and 
that they covered all spectrum, but getting this discussion underway is a positive development. 
Historians looking at American telecommunications policy may well view today as a day that 
heralded change not only with the nationwide vote that is taking place at the polls, but also the vote that 
takes place here to open the white spaces for broadband deployment. Both portend great progress for our 
future technological development. Just as I enthusiastically voted at the polls earlier this morning, I vote 
again enthusiastically for this item here today.

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STATEMENT OF 
COMMISSIONER ROBERT M. McDOWELL 
Re: Unlicensed Operation in the TV Broadcast Bands, ET Docket No. 04-186; Additional Spectrum for 
Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380 
To paraphrase astronaut Neil Armstrong as he became the first person to step on the moon, today 
the FCC is making both a small step and a giant leap. It will be a giant leap for American consumers to 
be able to use the untapped television white spaces. At the same time, we enter this new frontier with a 
small step in the form of a prudent and cautious order that sets up safeguards to ensure that new 
unlicensed devices do not cause harmful interference with licensees and other users of these frequencies. 
While new broadband technologies are the most likely uses of these channels, the most exciting 
part about our action today is that we are creating the opportunity for an explosion of entrepreneurial 
brilliance. Our de-regulatory order will allow the market place to produce new devices and new 
applications that we cant even imagine today. Not only will the lives of millions of Americans be 
enriched by these new technologies, but I am confident that imaginative use of the TV white spaces could 
actually improve our safety as well. 
We owe this historic moment to several white spaces pioneers including former FCC Chairman 
Michael Powell who initiated this proceeding four years ago, many Members of Congress, countless 
entrepreneurs and, of course, my Commission colleagues. I also acknowledge our chief engineer and 
technologist, Julie Knapp, and his entire OET team. Thank you for your patience, openness, fortitude and 
counsel. 
To those who have expressed concern regarding the results of this proceeding, I would like to 
offer them comfort in the form of the text of todays order. As a preliminary matter, I note that the 
empirical data we have studied suggests a very real potential for deployment of new personal/portable 
devices, and it would be premature to either wholly endorse or close the door entirely on future 
developments. Accordingly, it is appropriate that the steps today are limited in scope, define an outline 
for our future approach toward device certification and allow for any and all changes that may be required 
by future circumstances. 
We have listened carefully to the arguments of broadcasters, cable TV operators, wireless 
microphone companies and entertainers, and todays order addresses their concerns. In short, all avenues 
of modification and improvement remain open. And I thank my colleagues for working collectively to 
strengthen and clarify these protections. In fact, as technology improves, I expect that one day we will 
likely look back on this order and think of it as quaint; but today it is state-of-the-art. 
Our decision today also obviates the need for artificial government mandates, such as those 
imposed on the C Block of our 700 MHz auction. Make no mistake, I have long advocated application 
and device portability as well as free and open networks. Consumers want these features, and the market 
started working on delivering them years before unnecessary, counterproductive and after-the-fact 
Commission mandates. Therefore, if such mandates were not necessary then, they are even more 
unnecessary after our action today. Robust unlicensed use of white spaces will give nimble entrepreneurs 
the freedom to disrupt the market in positive and constructive ways that will force incumbents to keep 
pace with this new revolution. As a result, the pressure created by dynamic competition will knock down 
barriers created by walled gardens and pry open closed networks. This liberation will come about not 

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through increased regulation, but through increased competition. Our ultimate shareholders, American 
consumers, will reap the dividends. 
I also appreciate my colleagues support for a notice of inquiry to commence an examination of 
possible other limited uses of white spaces, such as point-to-point backhaul in rural areas as a substitute 
for special access. This is an idea that was raised in our original notice, is thoroughly discussed on the 
record, and is already ripe for decision. I still believe that a further notice of proposed rulemaking would 
have presented us with a clearer path toward a closer examination. Nonetheless, I hope my colleagues in 
the next Commission will move forward expeditiously on what I believe to be a win-win solution. 
Here is the challenge: all wireless services have to be backhauled to the PSTN and the Internet 
via a network of some kind. Over the years, some people in the tech industry, as well as some of my 
colleagues, have complained about a lack of competition in the special access market which, they allege, 
artificially drives up backhaul costs. Competitive local exchange carriers (CLECs) and competitive 
wireless carriers presented us with a possible solution to this challenge for rural areas which enjoy more 
unused spectrum than urban areas and suffer from the least amount of special access competition. Some 
form of limited white spaces point-to-point licensing may allow entrepreneurs to find more efficient paths 
for their backhaul needs while leaving the lions share of white spaces spectrum on the table for 
unlicensed users. 
I am disappointed by some in the tech industry and public interest community who seem to 
oppose the Commission even discussing this issue while also complaining about the condition of the 
special access market. All of us should remember that CLECs, wireless companies and their supplier 
partners are also part of the tech industry and their voices should be heard as well. Hopefully, this notice 
of inquiry can plant the seeds of progress to find a workable solution that inures to the benefit of all 
parties, but mainly, American consumers. 
Our decision today is revolutionary. It does more than simply foster the development of exciting 
new wireless services. It also has the potential to sustain the continuing good health of an old 
technology: television broadcasting, by protecting the interests of the millions of consumers who 
continue to rely on broadcasting for their news, entertainment and public safety information. 
Accordingly, I strongly support todays order.

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STATEMENT OF 
COMMISSIONER DEBORAH TAYLOR TATE 
APPROVING IN PART AND DISSENTING IN PART 
Re: Unlicensed Operation in the TV Broadcast Bands, ET Docket No. 04-186, Additional Spectrum 
for Unlicensed Devices Below 900 MHz and in the 3 GHz Band, ET Docket No. 02-380 
In the midst of the present economic downturn gripping our nation and the world, there is one bright 
spot on the horizon  American technology and the American entrepreneurial spirit, especially in the 
communications and technology sector, which hold the promise of future innovation, investment, jobs 
and economic growth. One of the more promising areas of innovation cannot even be seen  the white 
spaces that represent the unused portions of spectrum in the bands presently allocated to TV broadcast 
operations. Todays item advances us on a path to facilitate use of the white spaces for new wireless 
services, including broadband services, for all Americans. 
These are first steps only, ones that hopefully will move us towards modernization and more effective 
use of the unused portions of this spectrum. Indeed, these are revolutionary times in an evolutionary 
industry, with the promise of even yet unseen innovative devices on the horizon. Many visions exist for 
how unlicensed use of the white spaces will evolve, but evolve they certainly will. Hopefully, this item 
will help facilitate the deployment of unlicensed devices and services that enable consumers to enjoy 
more television programming and video than ever before, and that will allow families to transfer and 
network information, photos, and much more across multiple devices, technologies and platforms in their 
homes. Similarly, communities of users may find they are able to communicate seamlessly through mesh 
networks rather than traditional phone lines. Finally, as someone who has championed rural America, I 
hope that this item will facilitate services, including broadband, to rural areas and thus help reduce the 
digital divide that is far too prevalent in rural communities across our nation. 
In considering this order, I have listened to and weighed seriously the concerns of an amazingly 
broad array of interests. In the end, I have tried to reach a reasonable position that takes into account all 
interests, including, most especially, the interests of the American consumer. The order is not perfect  it 
precludes licensed services and lacks needed language regarding a specific and expedited complaint 
process for broadcasters, cable providers, wireless microphones and individual users in the case of 
interference. Nonetheless, the order ultimately may help promote the innovation and investment in 
advanced services that consumers have come to expect from the communications and technology sector. 
Accordingly, I would like to address several important public policy goals, as well as some of my 
concerns regarding how this item falls short of our mandate to advance the interests of the American 
public. 
Measures to Address Interference 
In crafting public policy, one must weigh the benefits and costs of various options. In this case, the 
potential costs of enabling unlicensed use of the white spaces are substantial. Specifically, this order 
enables a vision for entirely new services and devices but ones that also hold a real risk of causing 
interference with existing services, including broadcasting, cable television, and wireless microphones, 
among others. 
Addressing interference in the use of the spectrum has always been one of the primary roles of 
the Federal Communications Commission since its creation by Congress in 1934. Our predecessor 
agency, the Federal Radio Commission, also assumed this important responsibility starting as early as 
1927. Clearly, addressing interference is one of the crucial tasks this agency takes most seriously and 
performs most effectively. 

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Within the Commission, the Office of Engineering and Technology (OET) is the team responsible for 
conducting the research, analysis, and evaluation of devices that use the airwaves in this country. This 
group of talented staff has spent the past four years carefully considering whether and to what extent 
unlicensed devices may utilize the white spaces in the broadcast spectrum without causing undue harm to 
incumbent users. I have placed much faith in the Chief of OET, Julie Knapp, and his entire staff of 
engineers. Their recommendations, while always useful in any rulemaking, played an especially 
persuasive role in my final decision to support this item. 
I have been assured by Chief Knapp and our top engineers that the risks of interference have been 
appropriately considered. Ultimately, as the Commissions most recent report states, the extensive testing 
by OET has provided proof of concept for some types of unlicensed devices to use the white spaces. 
Further, as this order makes very clear, all devices that in the future will be used in the U.S. market must 
first be tested and approved by the Commission, in effect demonstrating not only that there is proof of 
concept but also proof in practice. While some commenters have criticized our testing process, both 
our 2007 and 2008 reports on the test results were peer reviewed by other expert staff within the 
Commission. In addition, these tests were open to the public, and at various points during this long 
process the work of our OET engineers was observed by members of the press, Congressional staff, 
broadcasters and other industry representatives, as well as other interested parties. I am proud of this 
transparent and open process and encourage OET to continue this commitment going forward. 
Based on the results of these tests, this order establishes a number of significant technical rules 
related to unlicensed use of the white spaces in the broadcast bands. Power limits are more restricted  to 
40 milliwatts, or a fraction of what wireless microphones are authorized to employ in these frequencies  
when operated in a channel immediately adjacent to a broadcast service, while a higher power limit 
applies in non-adjacent channels. 
In addition, and of critical importance to incumbent providers, the item will create a database of 
existing operations in specific channels and entire geographic areas that will remain unavailable to all 
unlicensed operations. Incumbent providers may register their locations and unlicensed devices will be 
required to first verify that channels are available prior to accessing them. This requirement to use this 
database will ensure that broadcast operations, broadcast auxiliary services (BAS), cable head-ins, public 
safety operations, and venues such as sports stadiums and theatres may register their locations and receive 
complete protection. 
The Commission, through our Enforcement Bureau and in consultation with the Office of 
Engineering and Technology, will investigate complaints of interference and take appropriate action, as 
we do with all cases of interference. I regret that my colleagues were unwilling to set forth in this item a 
more specific and swift process to deal with complaints of interference. I remain concerned that the item 
is too vague and does not provide necessary protections after the interference has occurred. 
I also would like to acknowledge the legitimate concerns of the many industries that already 
provide valuable services using the core TV bands. Regarding the concerns of my friends in the 
broadcasting industry, I want to recognize the important service they provide, especially all they currently 
are doing to make the DTV transition as smooth as possible. Over 90 percent of Americans are now 
aware of the DTV transition, thanks in large part to the more than $1 billion invested by the broadcasters 
and the cable industry in PSAs and other public education efforts. The DTV transition is an extraordinary 
opportunity for consumers to receive revolutionary TV picture quality and additional programming, as 
well as new wireless services that will be available in the 700 MHz band when those channels are 
vacated. In addition, broadcasters play a key role in providing emergency alerts to the public. It is, 
therefore, imperative that TV broadcasting continue to be protected from interference. The power limits 
and other technical rules, proposed by OET and adopted herein, are designed to do just that. 

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Regarding similar concerns by cable operators, I also recognize the potential for interference, 
both to cable head ends as well as to cable connections inside the home. The item takes steps to protect 
cable head ends by restricting use of white spaces devices in the geographic areas in which head ends are 
located. With regard to cable systems in the home, OET has attempted to establish power limits that will 
lower the risk of interference between devices in the home, though this risk is not, in my mind, fully 
mitigated. However, the Commission does not generally focus on interference that users cause to 
themselves. Just as we have all learned to move devices away from each other in the office and we no 
longer place our cell phones next to the computer, so might consumers need to reduce interference inside 
their home by moving devices, at least until the next generation of cable equipment becomes more widely 
disseminated. I encourage device manufacturers and indeed the Commission to provide information to 
consumers regarding these devices as they come online, as well as establishing 800 numbers, arming call 
centers with tech-specific solutions, email alerts, software fixes that lower power and other forms of 
outreach to consumers. 
Regarding the concerns of facilities and events managers  including Broadway, sports stadiums, 
churches, my friends at the Grand Ole Opry, and many others  the geographic database provides a 
critical line of defense. In addition, the item will make spectrum available in two channels above Channel 
20 in those markets that are particularly congested due to public safety operations in Channels 14  20. 
Taken together, these measures should protect the vast majority of wireless microphones. 
Remaining Concerns 
While the use of white spaces by unlicensed devices holds great promise and I am excited about 
their potential, I also have several significant concerns that I believe we should have addressed and 
encourage a future Commission to re-address. 
With regard to the possibility of interference, I regret that the Order does not include language 
that would specifically state the legal responsibilities of those who provide these new unlicensed devices. 
In particular, I would like providers of these devices to have clear notice of what they must and must not 
do under the Commissions rules. Perhaps more important still, I wanted to ensure that our rules specify 
that, in the event of significant interference caused by an unlicensed device, the party responsible for this 
device will also be responsible for rectifying the problem and assume the cost. Some companies have 
assured us that this will be the case; that their business reputation requires it and it is indeed good 
business for them to correct the situation. However, the potential impact of millions of devices in the 
marketplace calls for a prudent process for recall, provisions for mitigating interference caused by faulty 
equipment, and a clear exposition of fines and penalties for violations. I felt it was imperative to deal 
with this on the front end, but todays item is not sufficiently clear on these matters. I hope the next 
Commission will address this before, rather than after, any harm occurs. 
In addition, I am disappointed that this item does not take more specific steps to address higherpower 
fixed operations in rural areas, which could have been used to provide much needed backhaul, a 
key component of broadband service in rural communities. While I understand that the Commission will 
issue a Notice of Inquiry on this issue, this is too little and too late. Rural consumers need help now, and 
the record on the various options  including licensed approaches  is sufficiently developed for the 
Commission to take action today. 
More fundamentally, and most troubling about todays order, the Commissions decision makes it 
difficult if not impossible to allow anything other than unlicensed use in the white spaces of the roughly 
300 megahertz that comprise the TV broadcast spectrum. Other valuable uses, such as licensed 
operations, are precluded. I am not convinced that all of the white spaces in Channels 2  51 needed to be 

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made available for unlicensed use. Indeed, many of the companies that have discussed with me their 
exciting new business models have focused only on the use of Channels 21  51. 
As with any policy decision, we must be cognizant of the opportunity cost  that is, we must look 
with a clear head at that which we are giving up. This is extremely valuable spectrum  beachfront 
property spectrum  with estimates of the value of white spaces under a licensed approach ranging from 
$8 billion to over $24 billion. Even if the low estimates in this range are the most accurate, we must 
consider this lost value to the U.S. Treasury and, ultimately, to taxpayers. Even more important than the 
lost auction revenues, the consumer benefits of spectrum use in a licensed regime are many times greater 
than what service providers pay to the U.S. Treasury. Of course, the benefits to consumers of services in 
unlicensed bands also may be significant. But if all white spaces spectrum in this band is set aside for 
unlicensed use  rather than appropriately balancing licensed and unlicensed approaches  we are likely 
to ignore the huge value of alternative uses. In short, we need to consider the tradeoffs, and the American 
consumer  in urban as well as rural areas  will suffer if we do not. 
Based on my conversations with OET, independent engineers and various members of the White 
Spaces Coalition, it would appear that allowing unlicensed use of the white spaces only in Channels 31- 
51 would be sufficient to provide four channels  that is, 24 megahertz  in even the most congested 
markets and many, many more channels in suburban and rural markets. As an example, 24 megahertz is 
greater than the amount of spectrum made available in the largest block in the 700 MHz auction held this 
spring. In that auction, the C block sold for $3.7 billion, despite significant use restrictions that arguably 
lowered the final bid. While four channels of white spaces creating 24 megahertz would not represent 
contiguous spectrum, this nonetheless would be sufficient for broadband services in these highly 
congested markets. Other urban markets would have somewhat more spectrum available, while rural 
markets might have as much as 100 megahertz more spectrum available. 
Accordingly, I am not convinced that making Channels 21  51 available only for unlicensed use 
is necessary to create the types of exciting new services that have been predicted. I am even less 
convinced  and the record does not support  that we must make the entire core TV band, Channels 2  
51, available for such use. This is more spectrum than was requested by most of the parties who argued 
that they could provide new and innovative services using Channels 21  51. Therefore, while I 
supported moving forward to allow a portion of the white spaces be made available for unlicensed use, I 
respectfully dissent from including all channels in the band plan in this order. 
I thank Chief Julie Knapp, the fine staff at OET, and all those who have worked so hard on this 
item, including the many hours spent testing and analyzing devices. However, this was only a step on this 
incredible technology journey. Testing on individual devices will now commence and must be subject to 
the same stringent, thorough, and transparent procedures and reporting we have seen thus far in this 
process, consistent with the Commissions procedures for all device certifications. In addition, it is of 
critical importance that the Commission establishes and ensures a process that will immediately respond 
to and mitigate any interference experienced by incumbent users and individual consumers alike.