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Monday,

December 6, 2010

Part V

FederalCommunicationsCommission47 CFR Parts 0 and 15

Unlicensed Operation in the TV BroadcastBands; Final Rule

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75814 Federal Register / Vol. 75, No. 233 / Monday, December 6, 2010/ Rules and Regulations

FEDERAL COMMUNICATIONSCOMMISSION

47 CFR Parts 0 and 15

[ET Docket No. 04186 and 02380; FCC10174]

Unlicensed Operation in the TVBroadcast Bands

AGENCY: Federal CommunicationsCommission.

ACTION: Final rule.

SUMMARY: This document finalizes rulesto make the unused spectrum in the TV

bands available for unlicensedbroadband wireless devices. Thisparticular spectrum has excellentpropagation characteristics that allowsignals to reach farther and penetratewalls and other structures. Access tothis spectrum could enable morepowerful public Internet connectionssuper Wi-Fi hot spotswith extendedrange, fewer dead spots, and improvedindividual speeds as a result of reducedcongestion on existing networks. Thistype ofopportunistic use of spectrumhas great potential for enabling access toother spectrum bands and improvingspectrum efficiency. The Commissionsactions here are expected to spurinvestment and innovation inapplications and devices that will beused not only in the TV band buteventually in other frequency bands aswell.

DATES: Effective January 5, 2011 exceptfor amendments to 15.713, 15.714,15.715 and 15.717, which containinformation collection requirements thatare not effective until approved by theOffice of Management and Budget. TheCommission will publish a document inthe Federal Register announcing theeffective dates for those amendments.

FOR FURTHER INFORMATION CONTACT:Hugh Van Tuyl, Policy and RulesDivision, Office of Engineering andTechnology, (202) 4187506 or via e-mail [email protected].

SUPPLEMENTARY INFORMATION: This is asummary of the Commissions Second

Memorandum Opinion and Order, ETDocket No. 04186 and 02380, adoptedSeptember 23, 2010 and releasedSeptember 23, 2010. The full text of thisdocument is available on theCommissions Internet site at http://www.fcc.gov.It is also available forinspection and copying during regular

business hours in the FCC ReferenceCenter (Room CYA257), 445 12thStreet, SW., Washington, DC 20554. Thefull text of this document also may bepurchased from the Commissionsduplication contractor, Best Copy and

Printing Inc., Portals II, 445 12th St.,SW., Room CYB402, Washington, DC20554; telephone (202) 4885300; fax(202) 4885563; [email protected].

Paperwork Reduction Act of 1995Analysis

This document adopts new or revised

information collection requirementssubject to the Paperwork Reduction Actof 1995 (PRA), Public Law 10413 (44U.S.C. 35013520). The requirementswill be submitted to the Office ofManagement and Budget (OMB) forreview under section 3507(d) of thePRA. The Commission will publish aseparate notice in the Federal Registerinviting comment on the new or revisedinformation collection requirementsadopted herein. The requirements willnot go into effect until OMB hasapproved them and the FCC haspublished a notice announcing theeffective date of the informationcollection requirements. In addition, wenote that pursuant to the Small BusinessPaperwork Relief Act of 2002, PublicLaw 107198, see 44 U.S.C. 3506(c)(4),we previously sought specific commenton how the Commission might furtherreduce the information collection

burden for small business concerns withfewer than 25 employees.

Summary of the Second MemorandumOpinion and Order

1. In this Second MemorandumOpinion and Order, the Commissionaddresses on reconsideration a wide

variety of issues relating to unlicenseduse of the TV bands. These issuesinclude protection criteria forincumbent authorized services,technical rules for TV bands devices, TV

bands database requirements, thechannels that can used by TV bandsdevices, and several miscellaneousissues. The Commission is generallyupholding the decisions it made in theSecond Report and Order andMemorandum Opinion and Order(Second Report and Order) in thisproceeding, 74 FR 7314, February 17,2009. with some specific revisions and

clarifications. In this regard the actionstaken here are consistent with andcontinue the approach towardsauthorization of unlicensed devices inthe TV bands that the Commissionenunciated in the Second Report andOrderits actions in this proceeding areto be a conservative first step thatincludes many safeguards to preventharmful interference to incumbentcommunications services. TheCommission does, however, agree withpetitioners with regard to a number ofthe requested changes to the rules and

are modifying and clarify our rules asappropriate in granting those requests.The Commission believes these changesand clarifications will provide forimproved protection of licensed servicesin the TV bands, resolve certainuncertainties in the rules and providemanufacturers with greater flexibility indesigning products to meet market

demands. The Commission decisionsgranting and denying the variousrequests for changes to our rules for TV

bands devices are discussed.2. With the issuance of this decision

and the forthcoming decision by theCommissions Office of Engineering andTechnology on selection of one or moredatabase managers, manufacturers will

be able to begin to make unlicensed TVbands devices and systems available toconsumers, business and governmentusers for general use. The Commissionintends to closely oversee theintroduction of these devices to the

market and will take whatever actionsmay be necessary to avoid, and ifnecessary correct, any harmfulinterference that may occur. Further, theCommission will consider in the futureany changes to the rules that may beappropriate to provide greater flexibilityfor development of this technology andprotect against harmful interference toincumbent communications services.

3. Specifically, the Commission isresolving on reconsideration certainlegal and technical issues in order toprovide certainty concerning the rulesfor operation of unlicensed transmittingdevices in the television broadcast

frequency bands (unlicensed TV bandsdevices, or TVBDs). Resolution of theseissues will allow manufacturers to beginmarketing unlicensed communicationsdevices and systems that operate onfrequencies in the TV bands in areaswhere they are not used by licensedservices (TV white spaces). Theopening of these bands for unlicenseduse, which represents the firstsignificant increase in unlicensedspectrum below 5 GHz in over 20 years,will have significant benefits for both

businesses and consumers and willpromote more efficient spectrum use.

4. The Commission responds toseventeen petitions for reconsiderationthat were filed in response to theSecond Report and Orderin thisproceeding. These petitions collectivelyrequest numerous changes in the rulesfor TV bands devices. The Commissionis upholding the majority of its priordecisions on the issues raised therein. Inthis regard, the Commission continuesto believe that the approach it followedin the Second Report and Orderisdesirable and appropriate for this firststep in allowing unlicensed operations

mailto:[email protected]:[email protected]://www.fcc.gov/http://www.fcc.gov/mailto:[email protected]:[email protected]:[email protected]://www.fcc.gov/http://www.fcc.gov/mailto:[email protected]


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75815Federal Register / Vol. 75, No. 233 / Monday, December 6, 2010/ Rules and Regulations

in the TV bands. The Commission does,however, find merit in a number of therequests for changes to the rules forTVBDs and is granting those requests bymodifying and clarifying the rules infour areas. Specifically, the Commissionis taking the following actions: Protection Criteria for Incumbent

Services

Modifying the protection criteriafor low power auxiliary stations such aswireless microphones to reduce therequired separation between suchdevices and unlicensed personal/portable devices operating in Mode II.

Modifying the definition of thereceive sites entitled to protectionoutside of a television stations servicearea to include all multi-channel videoprogramming distributors as defined byour rules.

Reserving two vacant UHFchannels for wireless microphones andother low power auxiliary service

devices in all areas of the country. Allowing operators of event andproduction/show venues that use largenumbers of wireless microphones on anunlicensed basis that cannot beaccommodated in the two reservedchannels and any others available atthat location to register the sites of thosevenues on TV bands databases toreceive the same geographic spacingprotections afforded licensed wirelessmicrophones.

Restricting fixed TV bandsdevices from operating on locationswhere the ground level is more than 76meters above the average terrain level in

the area. TV Bands Devices Eliminating the requirement that

TV bands devices that incorporate geo-location and database access must alsolisten (sense) to detect the signals of TVstations and low power auxiliary servicestations (wireless microphones). As partof that change the Commission is alsorevising and amending the rules inseveral aspects to reflect use of thatmethod as the only means fordetermining channel availability. Whilethe Commission is eliminating thesensing requirement for TVBDs, it is

encouraging continued development ofthis capability because it believes that itholds promise to further improvementsin spectrum efficiency in the TVspectrum in the future and will be avital tool for providing opportunisticaccess to other spectrum bands.

Adopting power spectral densitylimits for unlicensed TV bands devices.

Modifying the rules governingmeasurement of adjacent channelemissions.

Restricting fixed TV bandsdevices from operating at locations

where the height above average terrainof the ground level is greater than 76meters. TV Bands Database Requiring that communications

between TV bands devices and TVbands databases, and between multipledatabases, are secure.

Requiring that all information

that is required by the Commissionsrules to be in the TV bands databases bepublicly available. Use of TV Channels Amending the rules to protect

Canadian and Mexican stations in theborder areas by including those stationsin the TV bands database as protectedservices.

Changing the protection zone forthe radio astronomy facility nearSocorro, New Mexico to a rectangulararea.

Declining to grant a request byFiberTower to set aside TV channels forfixed licensed backhaul use.

5. The Commission also makes otherminor changes and refinements to itsrules for TV bands devices. With thesechanges and clarifications, the rules will

better ensure that licensed services areprotected from interference whileretaining flexibility for unlicenseddevices to share the TV bands withthem.

Protection Criteria for IncumbentServices

TV Stations

6. In the Second Report and Order,the Commission adopted technical

criteria for determining when a TVchannel is considered vacant for thepurpose of allowing operation of anunlicensed device on that channel. Itprotected full service TV stations andClass A TV, low power TV, TVtranslator and TV booster stations frominterference within defined signalcontours. The signal level defining atelevision stations protected contourvaries depending on the type of station,e.g., analog or digital TV, and the bandin which a TV station operates, e.g.,VHF or UHF. The protected contours foranalog TV stations are calculated in

accordance with the F(50,50) curvesspecified in the Commissions rules, andthe protected contours for digital TVstations are calculated in accordancewith the F(50,90) curves. While part 74of the rules protects low power stationsto a higher signal strength contour, andtherefore to a shorter distance, than fullservice TV stations, the Commissiondecided to require TV bands devices toprotect low power stations to the samecontour as full service TV stations.

7. Decision. The Commission affirmsits decisions regarding the protection

contours for TV stations. First, theCommission declines to change themethod that must be used to calculateTV station protected contours. No partyhas described an alternative model thatwill provide more accurate calculationsof TV station contours than theCommissions current method. Thecurrent method of calculating TV station

contours in 73.684 of the rules usingthe FCC curves in 73.699 of the rulesis straightforward, well understood andhas proven sufficiently accurate overtime. Given the lack of compellinginformation to the contrary, theCommission believes that calculationsof channel availability relying on thatmethodology will provide satisfactoryprotection of TV services. Further, withrespect to Adaptrums request that TVsignal information be incorporated intothe TV bands databases, theCommission is removing therequirement that TV bands devices that

include a geo-location capability andaccess to a database must sensetelevision and low power auxiliarystations. Thus, sensing information onthe location of TV signals would not beavailable to incorporate into thedatabase. The Commission agrees withRudman/Ericksen that the TV bandsdevice database should includeinformation on transmit antenna beamtilt to permit TV contour calculations to

be made consistent with part 73 of therules and is modifying 15.713(h) of therules accordingly.

8. The Commission also affirms itsdecision to protect low power television

stations to the same signal contour asfull service TV stations. Low powerstations may provide the only over-the-air broadcast services in rural areas, andthe Commission disagrees that viewersof those stations should receive lessprotection than viewers of full servicestations. Further, low power stations bytheir nature cover only a relatively smallarea, so a modest increase in theprotected area beyond the defined part74 contour for these stations will notsignificantly impact the deployment ofTV bands devices.

9. The Commission disagrees with

SBE and Community Broadcasters thatthe rules fail to protect analog TVstations. While the D/U protection ratiosfor analog TV stations are higher thanfor digital stations, the protected servicecontours for analog stations are alsohigher than for digital stations. The netresult is that the level of an undesiredsignal from a TVBD that will causeinterference to an analog station ishigher than the level that will causeinterference to a digital station. Thus,the Commissions standards forprotection of digital TV stations from



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interference caused by TVBDs whenapplied for protection of analog TVstations provide somewhat greaterprotection of analog TV stations thanwould standards produced from asimilar analysis that specificallyconsidered protection of analog TVstations. The Commission also finds thatan analysis focusing on digital operation

is appropriate for low power televisionstations because these stations willeventually convert to digital operation.

10. The Commission declines to adoptany new requirements related to the useof TV bands devices in close proximityto amplified indoor antennas. A TV

bands device and a TV receiver in closeproximity would be under the control ofthe same party who could take steps toeliminate interference. The Commissionpreviously adopted a requirement in theSecond Report and Orderrequiringmanufacturers to provide information toconsumers on possible methods to

resolve interference to television in theevent it occurs, so the Commission findsno need to adopt any additionalrequirements.

Wireless Microphones and Other LowPower Auxiliary Stations

11. In the Second Report and Order,the Commission decided that thelocations where licensed part 74 lowpower auxiliary stations, includingwireless microphones, are used can beregistered in the TV bands devicedatabase and will be protected frominterference from TV bands devices. TV

bands devices may not operate co-

channel to a registered low powerauxiliary station within a distance of 1kilometer of the registered coordinates.

12. Decision. The Commissioncontinues to recognize that wirelessmicrophones are currently used in manydifferent venues where people gather forevents large and small and manyconsumers and businesses have come torely on these devices. The Commissionhas previously limited use of channels2 and 520 to communications betweenfixed TVBDs and reserved two channelsin the range 1451 in the 13 marketswhere PLMRS and CMRS systems

operate to make sure that frequenciesare available for wireless microphones.The Commission herein expands thereservation of two channels in the range1451 to all markets nationwide assuggested by several petitioners. Thiswill provide frequencies where alimited but substantial number ofwireless microphones can be operatedon any basis without the potential forinterference from TV bands devices. Itwill also ensure that frequencies areavailable everywhere for licensedwireless microphones used on a roving

basis to operate without risk of receivingharmful interference from TVBDs. TheCommission has also provided for anominal separation distance betweenTVBDs and sites of venues and eventswhere large numbers of unlicensedwireless microphones used bypermitting such sites to be registered inthe TV bands databases. Further, it

notes that at any particular location anumber of TV channels will not beavailable for use by TVBDs due to theapplication of the various interferenceprotection requirements under ourrules. Thus, a significant amount ofspectrum will be available on whichwireless microphones can be operatedas they have in the past without concernfor interference from TVBDs. TheCommission believes that this spectrumwill provide sufficient frequencies tosupport wireless microphone operationsat the great majority of events. TheCommission disagrees with those who

argue that more spectrum should bereserved for wireless microphones. Itobserves that wireless microphonesgenerally have operated veryinefficiently, perhaps in part due to theluxury of having access to a wealth ofspectrum. While there may be users that

believe they need access to morespectrum to accommodate morewireless microphones, the Commissionfinds that any such needs must beaccommodated through improvementsin spectrum efficiency. The Commissionunderscored this point in the currentlypending wireless microphone

proceeding and sought comment onsolutions that could enable wirelessmicrophones to operate more efficientlyand/or improve their immunity toharmful interference, See Report andOrder and Further Notice of ProposedRule Makingin WT Docket Nos. 08166and 08167 and ET Docket No. 1024,25 FCC Rcd 643, 702 (2010), FCC 1016, 75 FR 9113, March 1, 2010. TheCommission will continue to pursuethis issue as it considers possiblerepurposing of the TV spectrum.

13. The Commission disagrees withthe petitioners that argue unlicensedwireless microphones should be subjectto the same requirements as TVBDsunder the rules. There are manyimportant differences that make itimpractical to apply the same rules to

both types of devices. For example,TVBDs are expected to be data devicesthat will have access to the Internet.Wireless microphones do not typicallyinclude geo-location technology nor dothey connect to the Internet, sorequiring these devices to check forchannel availability through a databasewould be impractical. Also, TVBDs

generally should be able to toleratesome latency, whereas wirelessmicrophones operate in real time andgenerally cannot tolerate significantlatency. Most importantly, unlicensedwireless microphones have beenoperating for quite some time withoutcausing harmful interference.Accordingly, the Commission concludes

that unlicensed wireless microphonesshould not be subject to the moreconfined approach it has applied toTVBDs.

14. With regard to registration ofunlicensed devices in the TV bandsdatabases, the Commission firstobserves that unlicensed wirelessmicrophones operate under the samegeneral conditions of operation in 15.5of the rules as TV bands devices,meaning they may not causeinterference to authorized services andmust accept any interference received,including interference from other non-

licensed devices. As a general matter,the Commission therefore finds that itwould be inappropriate to protectunlicensed wireless microphonesagainst harmful interference from otherunlicensed devices, and in particularTV bands devices. The Commissionobserves that there are a wide variety ofapplications for wireless microphonesranging from a single wirelessmicrophone used by a performer orpresenter, to small theatricalproductions using perhaps 1020microphones, to large scale productionsand events such as professional sports

events and Broadway style productionsthat may use well over 100 wirelessmicrophones. The overwhelmingmajority of such use does not meritregistration in the TV bands database. Incases where the number of wirelessmicrophones needed for an event isrelatively low, the operator ofunlicensed microphones can avoidreceiving harmful interference fromTVBDs by simply using the reservedchannels or other channels in eachmarket where TVBDs are not allowed tooperate. The two reserved TV channelswill accommodate a minimum of atleast 16 wireless microphones, and theadditional channels that are notavailable for TVBDs at most locationswill accommodate many additionalwireless microphones. On the otherhand, the Commission recognizes thatcertain events, such as major sportingcontests or live theatrical productions/shows, may use scores of wirelessmicrophones and therefore may not beable to be accommodated in the tworeserved channels and other channelsthat may be available for wirelessmicrophones at that location.



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15. Accordingly, the Commission isaddressing unlicensed wirelessmicrophones and low power auxiliarydevices in our rules for TV band devicesas follows. As the general rule, it is notallowing unlicensed wirelessmicrophones and other low powerauxiliary devices operating without alicense to be registered in the database;

these devices will not be affordedprotection from interference from TV

bands devices on channels where TVbands devices are allowed to operate.Entities desiring to operate wirelessmicrophones on an unlicensed basiswithout potential for interference fromTVBDs may use the two channels ineach market area where TVBDs are notallowed to operate, as well as other TVchannels that will be available in thevast majority of locations. Such entitiesmay consult with a TV bands databaseto identify the reserved channels at theirlocation, as well as the TV channels that

may not be available for TV banddevices. Entities operating or otherwiseresponsible for the audio systems atmajor events where large numbers ofwireless microphones will be used andcannot be accommodated in theavailable channels at that location mayrequest registration of the site in the TV

bands databases. The registrationrequests must be filed with theCommission. Entities filing registrationrequests will be required to certify thatthey are using the reserved channelsand all other available channels from 751 (except channel 37) that are not

available for use by TV band devicesand are practicable for use by wirelessmicrophones. The request to beregistered must be filed with theCommission at least 30 days in advanceand include the hours, dates or days ofthe week and specific weeks on whichthose microphones will be in actual use(on dates where events are not takingplace, those sites will not be protected)and other identifying information alsorequired of low power auxiliarylicensees. Unlicensed microphones atevent sites qualifying for registration inTV bands databases will be afforded thesame geographic spacing from TVBDs aslicensed microphones. The Commissionalso advises entities responsible forevent sites qualifying for registration inTV bands databases that registrationdoes not create or establish any form orright or assurance of continued use ofthe spectrum in the future.

16. To allow it to better identifyregistered wireless microphone licensedoperations and unlicensed sites, theCommission adopted the followingregistration procedures. Operators oflicensed wireless microphones may

register sites directly with one of thedesignated database administrators andprovide the information required by therules, which the Commission isamending to include the wirelessmicrophone call sign. As indicated,operators of venues using unlicensedwireless microphones will be requiredto register their sites with the

Commission, which will transmit theinformation to the TV bands devicedatabase administrators. For thepurpose of this registration, theCommission will develop a form thatwill allow the information to be filedthrough one of the Commissionselectronic filing systems, such as theUniversal Licensing System (ULS). Theapplicant will be required to certify thatit complies with the requirements forregistration of unlicensed wirelessmicrophones, including that it will firstmake use of all TV channels notavailable for TV bands devices that are

practicable for wireless microphone use,including channels 751 (exceptchannel 37), and submit the informationspecified by the rules, which we areamending to include the name of thevenue where the equipment is operated.As a benchmark, at least 68 wirelessmicrophones must be operating in eachchannel that is being used for the event.Registration requests that do not meetthese criteria will not be registered inthe TV bands databases. TheCommission will take actions againstparties that file inaccurate or incompleteinformation, such as denial of

registration in the database, removal ofinformation from the database pursuantto 15.713(i), or other sanctions asappropriate to ensure compliance withthe rules. The Commission will makerequests for registration of sites that useunlicensed wireless microphones publicand will provide an opportunity forpublic comment or objections. TheCommission has delegated authority foradministering this registration processjointly to its Office of Engineering andTechnology and WirelessTelecommunications Bureaus.

17. The Commission is maintainingthe requirement that fixed TV bandsdevices may not operate co-channelwith low power auxiliary stationswithin 1 km of their coordinatesregistered in the TV bands databases.The Commission recognizes thearguments of Shure and CWMU aboutthe difference in power levels betweenfixed TV bands devices and wirelessmicrophones. However, whetherharmful interference occurs in aparticular situation depends on manyfactors, including the undesired signalpower, antenna directivity and

separation distance, as well as the levelof the desired signal at the receiver, thereceive antenna and receivercharacteristics, and any interveningstructures or terrain that could attenuatethe undesired signal. Neither Shure norCWMU provided an analysis with theirpetitions demonstrating that the 1 kmseparation distance adopted in the

Second Report and Orderis inadequatefor fixed devices when taking allrelevant factors into account. In caseswhere licensed low power auxiliarystations are being used at large outdoorvenues, such as racetracks or golfcourses, the Commission will permit theparty registering the devices to specifythe coordinates of multiple locationswithin the site to ensure that protectionis provided over the entire facilitywhere microphones are being used.

18. However, the Commission agreeswith petitioners that argue that it is notnecessary to provide low power

auxiliary stations the same protectionfrom personal/portable TV bandsdevices because the latter operate withpower levels at least forty times lowerthan the maximum power permitted forfixed TV bands devices. Therefore, it ismodifying the rules to require that ModeII (independent) personal/portabledevices not operate co-channel with lowpower auxiliary stations within 400meters (0.4 km) of their coordinatesregistered in the TV bands devicedatabase. A 100 mW transmitter willproduce a lower signal at 400 metersthan a 4 watt transmitter at 1 km usinga free space calculation, so this shorter

distance will provide greater protectionfor low power auxiliary devices from100 mW TV bands devices than a 1 kmseparation from 4 watt devices. TheCommission will use this same 400meters distance for personal/portabledevices that operate with less than 100mW of power.

19. The Commission finds that it isnot practical to protect wirelessmicrophones using informationobtained from the ULS and declines torequire that that information be used indefining such protection as suggested byRudman/Ericksen. Some wireless

microphones are licensed using specificcoordinates, while others are licensed toa wide area such as the entire servicearea of a TV station, and a license mayspecify multiple operating channels.The Commission also observes thatwireless microphones can be operatedintermittently at discrete locations,rather than continuously over a widearea. Thus, the use of ULS licensingdata could preclude TV bands devicesfrom operating on multiple channelsand at locations where no wirelessmicrophones are in operation.



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Translators, Cable Headends andMultichannel Video ProgramDistributors

20. In the Second Report and Order,the Commission adopted rules to protectTV translator receive sites and cable TVheadends that are located outside theprotected contours of the TV stations

being received. TV translator receivesites are often located on high towers orat high elevations and use high gainantennas to receive a full servicestations signal well beyond the stationsservice area. Cable headends arefacilities that acquire and distributevideo service signals over a cabletelevision system. Broadcast TV signalsare often received off-the-air at a cableheadend for retransmission over thecable system. In many cases, the cableheadend will use an antenna with highgain antenna mounted high on a towerto receive a TV stations signals well

beyond the stations service area in a

manner similar to that used by TVtranslators. The Commission found thatit is important to avoid disruption of TVservice to viewers who are located

beyond TV station service areas andable to receive those signals throughretransmission on TV translators andcable systems. While those viewers arein fact located beyond the areas wherethe Commission normally protects TVservices, in these cases TV services havede factobeen extended and valuableservice is being provided to a significantnumber of households. If a TV bandsdevice were to be located between the

TV translator/cable headend and TVstation and then operate on one or moreof the channels being received by thosefacilities in a manner that results inharmful interference, TV reception tothe households and the cable systemservices could be disrupted.

21. To protect cable headends and TVtranslator receive sites which are notlisted in Commission databases, theCommission allowed operators of TVtranslator receive sites and cableheadends that are located within 80 kmof the service contour of the received TVstation to register their location and the

channel(s) they receive in the TV bandsdevice database. To preventunnecessary entries into the database,the Commission permitted translatorreceive sites and cable headends to beregistered only if they are outside theprotected contour of the TV station

being received. The rules limitoperation of TV bands devices co-channel and adjacent to the channel(s)

being received over an arc of 30degrees from a line between the receivesite and the TV station(s) beingreceived. Within this arc, TV bands

devices operating co-channel to thereceived station may not operate within80 km of the receive site, and TV bandsdevices on channels adjacent to thereceived station may not operate within20 km of the receive site. The protectionradius extends only as far as theprotected contour of the station beingreceived, so the co-channel protection

distance would be less than 80 km forreceive sites closer than this distancefrom a protected contour, and both theco-channel and adjacent channelprotection distances would be less than20 km for receive sites closer than thisdistance from a protected contour. Inaddition, to prevent interference to TVtranslators and cable headends from TV

bands devices outside the main beam ofthe receive antenna, the Commissionprohibited TV bands devices fromoperating co-channel to the channel(s)

being received by these facilities within8 kilometers and from operating on

adjacent channels within 2 kilometersin all directions off the 30 degree arc.22. Decision. The Commission

modified the rules to expand and moreclearly define the types of receivefacilities that may be registered in theTV bands database and are makingcertain changes to the protection criteriafor these receive facilities. The purposeof permitting the registration of receivesites is to protect the reception of over-the-air TV signals that are redistributedthrough another means. Consistent withthis intent, the Commission will permitthe registration of TV receive sites forother types of video service providers

besides cable systems and is modifyingthe rules in this regard to more clearlyand completely define the types offacilities that may be registered. TheCommission therefore specifies thatreceive sites of all multi-channel videoprogramming distributors (MVPDs) asdefined by section 602(13) of theCommunications Act may be voluntarilyregistered in the database, in addition toTV translator receive sites.

23. The Commission recognizes thatthere are cable headends that receive TVstation signals located at distances

beyond 80 km from the edge of a

television stations protected servicecontour and understand NCTAsconcern for possible disruption serviceto cable subscribers. These sameconsiderations would apply to otherMVPDs and to TV translator, low powerTV and Class A TV stations that re-transmit programming from another TVstation. The Commission does not

believe that the requested change wouldhave significant impact on theavailability of TV white space becausethese facilities are generally in remoteareas where many channels will be

available for white space devices.However, the Commission alsorecognizes that parties may wish to havean opportunity to review such requeststo confirm the assessment. We aretherefore providing that current MVPDoperators, TV translator, low power TVand Class A TV stations with receivesites located beyond the 80 km co-

channel protection distance in the rulesmay apply for a waiver of that distanceduring a period that will end 90 daysafter the effective date of the rulesadopted herein. Such waiver requestswould also involve shifting the 20 kmadjacent channel protection distance sothat it is measured from the actualreceive site. The Commission will thenissue a public notice requestingcomment on requests it receives andissue decisions. MVPD operators andTV translator, low power TV and classA TV stations that commence operationin the future with receive sites located

beyond the co-channel and adjacentprotection distances may apply for awaiver of those distances within 90 daysof commencing operation. Followingreceipt of such request(s), theCommission will then issue a publicnotice asking for comment on therequest(s) and issue decision(s).

24. The Commission declines toincrease the width of the 30 degreeprotected arc as requested by NCTA. Areceive site located outside theprotected contour of a TV station wouldneed to incorporate a high gain receiveantenna, which has a narrow

beamwidth. While it recognizes NCTAs

argument that an antenna has side lobesthat will allow it to receive signalsoutside its main beam, this does not initself demonstrate that the currentprotection requirement is inadequate orthat a wider protected arc is necessary.Adaptrum provides no information tosupport its argument that the protectiondistance outside of the main lobe of thereceive antenna should be significantlyreduced and we therefore deny thatrequest. The Commission furtherdeclines to require operators of fixed TV

bands devices to coordinate withoperators of receive sites. The

requirements it has adopted areextremely conservative and willadequately protect receive sites, so acoordination requirement isunnecessary and would be cumbersometo implement.

25. The Commission finds itunnecessary to provide for registrationof receive sites within the protectedcontour of a TV station being receivedand thus declines to allow suchregistrations. Within a stationsprotected service contour, receive sitesare protected from interference by the



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same provisions that protect receptionby consumers. The rules require that TVbands devices be located outside thecontour of a co-channel TV station, soa TV bands device located near acontour that is communicating withanother TV bands device would not bedirecting its signal into the contourwhere the receive site is located.

Further, a receive site inside, but nearthe edge of a protected contour, wouldhave it receive antenna directed towardthe TV station and not at the TV bandsdevice outside the contour. Therefore,the orientation of the antennas in thissituation makes interference highlyunlikely. Additionally, a TV bandsdevice operating on a channel adjacentto an occupied TV channel is permittedto operate within the service contour,

but at a lower power level not to exceed40 mW. This lower power levelcombined with the fact that a receivesite within a contour will receive a

higher signal level than a receive siteoutside the contour makes adjacentchannel interference from that sourceagain unlikely. Furthermore, in theevent that interference does occur, theoperator of the TV bands device isrequired to cease operation.

26. Finally, the Commission ismodifying the text of the rules to clarifythat registration for receive sites islimited to channels that are receivedover-the-air and are used as part ofservice of the MVPD, TV translator, lowpower TV station or Class A TV station.The Commission is not limiting

registration to local channels so as notto preclude the possibility that anMVPD or TV translator/low powertelevision station may retransmit out-of-market channels if it is authorized to doso.

TV Bands Devices

Spectrum Sensing

27. In addition to requiring that TVbands devices access a database todetermine available channels, theCommission decided in the SecondReport and Orderto require that TV

bands devices be capable of sensing

analog TV signals, digital TV signalsand wireless microphone signals at alevel of114 dBm within definedreceiver bandwidths. This level isreferenced to an omni-directionalreceive antenna with a gain of 0 dBi. Ifa receive antenna with a minimumdirectional gain of less than 0 dBi isused, the detection threshold must bereduced by the amount in dB that theminimum directional gain of theantenna is less than 0 dBi. Alternativeapproaches for the sensing antenna arepermitted that provide at least the same

performance as an omni-directionalantenna with 0 dBi gain. TheCommission also required that thereceive antenna used by fixed devices

be located at least 10 meters above theground to maximize the likelihood thatits reception is not blocked fromreceiving signals originating from anydirection. It found that receive antenna

height requirements are impractical forpersonal/portable devices and declinedto impose such requirements on thosedevices.

28. Under the rules adopted in theSecond Report and Order, a TV bandsdevice is permitted to begin operatingon a TV channel if no wirelessmicrophone or other low powerauxiliary device signals above thedetection threshold are detected withina minimum time interval of 30 seconds.A TV bands device must also performin-service monitoring of channels onwhich it operates a minimum of once

every 60 seconds. There is no minimumchannel availability check time for in-service monitoring. If a device detects awireless microphone or other low powerauxiliary device signal on a channel itis using, the device must cease alltransmissions on that channel withintwo seconds. If a TV signal is detectedon a channel indicated as available foruse by the database, the TV bandsdevice must provide a notice of thatdetection to the operator of the deviceand provide a means for the operator toremove the channel from the deviceslist of available channels. However,with respect to TV signals, the database

is the controlling factor in determiningwhether a channel is available, andthere is no requirement for a TV bandsdevice to avoid operating on a channelwhere it detects a TV signal, since it ispossible to detect a signal outside astations protected service contour.

29. A personal/portable deviceoperating in Mode I must identify(report) those TV channels on which itsenses a wireless microphone ortelevision signal above the detectionthreshold to the fixed or Mode IIpersonal/portable device that provides itwith a list of available channels. The

fixed or Mode II device must respond asif it had detected the signal itself, i.e.,it must not use the occupied channel ifthe Mode I device detects a wirelessmicrophone and must report the TVsignal detection to the operator of thedevice. In addition, TV bands devicescommunicating either directly with oneanother or linked through a base stationmust share information on channeloccupancy determined by sensing. Ifany device in a local area group ornetwork determines that a channel isoccupied and notifies other devices

with which it is linked, all the otherlinked devices will be required torespond as if they had detected thesignal themselves.

30. Decision. The Commissioneliminated the requirement for TV

bands devices that rely on geo-locationand database access to sense analog anddigital TV signals and also wireless

microphones and other low powerauxiliary stations. Much of thisproceeding has focused on the centralquestion of whether spectrum sensing isa viable tool for providing access tospectrum. The Commission has notedthe benefits and limitations of spectrumsensing through testing conducted by itsengineers and extensive discussion inthe Second Report and Order. TheCommission continues to believe thatspectrum sensing will continue todevelop and improve. It anticipates thatsome form of spectrum sensing mayvery well be included in TVBDs on a

voluntary basis for purposes such asdetermining the quality of each channelrelative to real and potentialinterference sources and enhancingspectrum sharing among TVBDs.However, at this juncture, theCommission does not believe that amandatory spectrum sensingrequirement best serves the publicinterest. As petitioners and respondingparties indicate, the geo-location anddatabase access method and otherprovisions of the rules will provideadequate and reliable protection fortelevision and low power broadcastauxiliary services, so that spectrum

sensing is not necessary. With respect toprotection of television services, theCommission observes that the geo-location and database method is alreadythe primary means for preventinginterference to TV stations. The sensingrequirement adopted in the SecondReport and Orderonly requires that aTV bands device inform the user whena TV signal above a threshold isdetected and provide an opportunity forthe user to change channel, but it doesnot preclude operation on a channelwhere a TV signal is detected. That is,the Second Report and Orderessentially

relied on geo-location and the TV bandsdatabases to protect over-the-air TVbroadcasting, not spectrum sensing.

31. The Commission also nowconcludes that inclusion of a spectrumsensing capability is not necessary toprotect wireless microphone operations.Parties operating part 74 licensed lowpower auxiliary stations at fixedlocations are eligible to register thoseoperations in the TV bands devicedatabase to obtain interferenceprotection from TV bands devices. Asindicated, for parties ineligible for part



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74 licensing, the Commission, in itsWireless Microphone R&O/FNPRMpermitted the operation of low powerauxiliary service stations on anunlicensed basis under part 15 of therules pending a final decision on itsproposals to expand eligibility for part74 licensing and to allow a new categoryof wireless audio devices to operate in

the core TV bands under part 15. Basedon the Commissions informalobservations of the marketing and usesof wireless microphones, it appears thatthe number of wireless microphonesoperating under the part 15 waiversignificantly outnumbers thoseoperating as part 74 licensed devices.Unlicensed devices operate on a non-interference basis, meaning they maynot cause interference to authorizedservices, and must accept anyinterference received, includinginterference from other unlicenseddevices such as TV bands devices.

Requiring TV bands devices to senselow power auxiliary stations such aswireless microphones wouldinappropriately give interferenceprotection to a large number of otherunlicensed, unprotected devices

because there is no way for the sensingfeature of a TV bands device todistinguish licensed from unlicenseddevices. The Commission recognizesthat there will be some licensed lowpower auxiliary stations that can beused in roving applications for whichthe location cannot be known inadvance and therefore cannot be

registered in the TV bands devicedatabase. The Commission has reservedtwo channels at all locations on whichunlicensed TV bands devices will not beallowed to operate in order to ensurethat there are frequencies on whichlicensed microphones used in rovingapplications such as electronic newsgathering can operate. The availabilityof the frequencies in these channels willmake it unnecessary to provide specialprotection from interference for suchapplications.

32. With the elimination of thespectrum sensing requirement for TV

bands devices that use geo-location anddatabase access, there is collaterally nolonger a need for a minimum receiveantenna height for fixed devices, andthe Commission consequently isremoving that requirement from therules. The Commission also revised andamended certain elements of the rulesso that they continue to providecomparable assurance of protectionagainst interference in the absence ofsensing capabilities and to clarify andsimplify the rules as they pertain tointerference protection. In addition to

revisions of the geo-location anddatabase access rules, the changesinclude revision of certain terms used inthe rules and elimination of the termsclient device, client mode, masterdevice, and master mode.

33. As part of these changes, theCommission eliminated therequirements for devices operating in

Mode I to use distributed sensing. It alsoobserves that some of the comments onthis issue appear to reflect anunderstanding that the rules permitextensive networks of devices thatwould all be linked together using acommonly identified list of availablechannels. The Commission wishes tocorrect any misconceptions that, at leastat this stage, the rules contemplate orpermit such networks and sharing ofchannel availability information. Rather,as stated in the Second Report andOrder, the Commission will permitpersonal/portable TVBDs to be used in

the operation of networks only where ameans is provided to ensure that eachdevice is operating consistent with thechannels available at its particularlocation. The rules do not permitpersonal/portable devices operating inMode I to relay channel availabilityinformation from one Mode I device toanother Mode I device unless somemeans is used to ensure that each deviceis operating within the parameters forits particular location.

34. The Commissions elimination ofthe general requirement that all TV

bands devices perform spectrum sensingat least once per minute and report

channel availability information to otherdevices in a network removes the onlyexisting requirement in the rules for aMode I device to maintain contact witha fixed or Mode II device. In reviewingthis provision, the Commission alsoobserved that the rules currently do notrequire that a Mode I deviceperiodically re-establish its list ofavailable channels through either devicethat uses geo-location and databaseaccess; however, such re-checks forchannel availability are necessary toensure that a Mode I device does notcontinue to operate on a channel that

becomes unavailable. To address theseconcerns, the Commission is adding arequirement that a device operating inMode I must either receive a specialsignal from the Mode II or fixed devicethat provided its current list of availablechannels to verify that it is still inreception range of that device or contacta Mode II or fixed device at least onceper minute to re-verify/re-establishchannel availability. This newrequirement, including the specialsignal for verifying contact with theMode II or fixed device that provided

the Mode I devices list of availablechannels, is described in more detail inthe section below on Re-checkProcedures. This requirement isnecessary because a Mode I device isnot generally expected to be able todetermine when it has moved, and itcould possibly be moved to a locationwhere the operating channel is

occupied. Maintaining regular contactwith a Mode II or fixed device willensure that Mode I devices operate onlyon channels available at their locationand that they cease operation when theymove out of range of the device fromwhich they obtained their list ofavailable channels, in which case theirlist of available channels would nolonger be valid. This requirement willalso address situations where a Mode Idevice is no longer able to maintaincontact with an operating fixed or ModeII device (for example, if the fixed orMode II device with which the Mode I

device has been communicating ceasesoperation and the Mode I device is notable to contact a replacement).

35. In reviewing the rules in thiscontext, the Commission also observesthat 15.711(b)(3)(ii) of the rulesrequires that a Mode II personal/portable device access the database fora list of available channels each time itis activated from a power-off conditionand re-check its location and thedatabase for available channels if itchanges location during operation. It isthe Commissions intent that a Mode IIdevice monitor its location regularly todetermine if its location has changed

under this requirement. TheCommission therefore amended thissection of the rules to clarify that aMode II device must use its geo-locationcapability to check its location at leastonce every 60 seconds, except when insleep mode, i.e., in a mode in whichthe device is inactive but is notpowered-down. This clarification willensure that Mode II devices re-checktheir list of available channels within ashort interval if their location changes.It will also provide clarity with respectthe re-check requirements for devicesthat operate on a mobile basis within a

bounded geographic area in which thesame channels are available at alllocations.

36. While the Commission eliminatedspectrum sensing for TVBDs that usegeo-location and database access, itcontinues to believe that this technologyoffers significant promise for improvingspectrum access and efficiency both inthe TV bands and in providing access toother spectrum. Spectrum sensing hascome a long way and some haveexpressed the view that even today it issufficiently developed that it can be



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relied upon for determining access tothe TV bands and other spectrum. TheCommission is therefore leaving openthe opportunity to submit applicationsfor certification of sensing-only devices.It acknowledges that the process forapproval of such devices is rigorous.However, the Commission continues to

believe that an open and transparent

review as provided by that process isappropriate for sensing-only devices.Accordingly, the Commission retainedthe provisions in the rules that permitthe authorization and operation ofpersonal/portable TV bands devices thatrely on sensing alone under a proof-of-performance standard. TheCommission invites parties that submitsuch applications when they are readyto do so. The Commission takes thisopportunity to clarify that devices thatuse sensing alone may initiate andparticipate in a network of TVBDs andmay communicate with fixed, Mode I,

Mode II and other sensing-only TVBDsbut may not provide a Mode I devicewith a list of available channels. TheCommission is also re-locating theexisting spectrum sensing technicalprovisions that previously applied to allTVBDs into the rule section on sensing-only devices.

37. The Commission is also increasingthe minimum required detectionthreshold for wireless microphones andother LPAS stations of sensing-onlydevices from 114 dBm to 107 dBm. Itis making this change for two reasons.First, sensing-only devices must operatewith lower power than fixed or other

personal/portable devices (except forpersonal/portable devices operating onchannels adjacent to television stations),so a higher detection threshold wouldprovide a level of protection that isapproximately comparable to a lowerthreshold in a higher power device.Second, the rules for such devicesspecify that although compliance withthe detection threshold for spectrumsensing is required, it is not necessarilysufficient for demonstrating reliableinterference avoidance. Thus, therequired detection threshold we areadopting serves as a minimum

performance criteria for a device.38. Authorization of a sensing onlyTVBD under the proof-of-performancestandard also requires that amanufacturer submit a prototype devicethat will be tested by the Commission toensure that the device is capable ofoperating without interference prior tocertification. The decision on whetherto certify a sensing-only device will be

based on its performance, and inparticular its ability to reliably detectthe presence of authorizedtransmissions. If the Commission

determines through testing that a lowerdetection threshold is necessary toprevent interference then it will requirethe device to meet the lower threshold

before it could be certified. TheCommission believes that theserequirements for sensing-only devicesare sufficiently conservative to preventinterference to TV reception and low

power auxiliary stations. TheCommission sees no basis for increasingthe threshold for sensing of televisionsignals.

Technical Requirements

Antenna Height

39. Because the range at which a TVbands device can cause interferenceincreases as the height of the devicesantenna increases, the Commissionadopted a maximum antenna heightlimit of 30 meters above ground forfixed devices. This height limit wasintended to balance unlicensed fixed TV

bands device transmission range withthe distance at which those operationscould impact licensed services. TheCommission did not impose heightrestrictions on personal/portabledevices because it found that it is notpractical to administer an antennaheight limit for those devices and thelower power and limited antenna gainof personal/portable devices wouldgenerally result in propagation over ashorter range than fixed devices.Further, the Commission observed thatpersonal/portable devices, unlike fixeddevices which have gain antennas

mounted outdoors to maximize thepropagation range of their signals, willlikely typically be used indoors wheretheir signals will be attenuated byexterior walls. These factors willsignificantly reduce the range at whichsignals from a personal/portable devicewill be of sufficient field strength tocause interference.

40. Decision. The Commissiondeclines to increase the maximumpermitted transmit antenna height aboveground for fixed TV bands devices. Asthe Commission stated in the SecondReport and Order, the 30 meters above

ground limit was established as abalance between the benefits ofincreasing TV bands devicetransmission range and the need tominimize the impact on licensedservices. Consistent with theCommissions stated approach in theSecond Report and Orderof taking aconservative approach in protectingauthorized services, it finds the prudentcourse of action is to maintain thepreviously adopted height limit. If, inthe future, experience with TV bandsdevices indicates that these devices

could operate at higher transmit heightswithout causing interference, theCommission could revisit the heightlimit.

41. While the Commission expectsthat specifying a limit on antenna heightabove ground rather than above averageterrain is satisfactory for controllinginterference to authorized services in

the majority of cases, it also recognizespetitioners concerns about theincreased potential for interference ininstances where a fixed TV bandsdevice antenna is located on a localgeographic high point such as a hill ormountain. In such cases, the distance atwhich a TV bands device signal couldpropagate would be significantlyincreased, thus increasing the potentialfor interference to authorized operationsin the TV bands. The Commissiontherefore concludes that it is necessaryto modify our rules to limit the antennaHAAT of a fixed device as well as its

antenna height above ground. Inconsidering a limit for antenna HAAT,the Commission needs to balance theconcerns for long range propagationfrom high points against the typicalvariability of ground height that occursin areas where there are significant localhigh pointsthe Commission does notwant to preclude fixed devices from alarge number of sites in areas wherethere are rolling hills or a large numberof relatively high points that do notgenerally provide open, line-of-sightpaths for propagation over longdistances. The Commission finds thatlimiting the fixed device antenna HAAT

to 106 meters (350 feet), as calculated bythe TV bands database, provides anappropriate balance of these concerns. Itwill therefore restrict fixed TV bandsdevices from operating at locationswhere the HAAT of the ground isgreater than 76 meters; this will allowuse of an antenna at a height of up to30 meters above ground level to providean antenna HAAT of 106 meters.Accordingly, the Commission specifiesthat a fixed TV bands device antennamay not be located at a site where theground HAAT is greater than 75 meters(246 feet). The ground HAAT is to be

calculated by the TV bands databaseusing computational softwareemploying the methodology in 73.684(d) of the rules to ensure thatfixed devices comply with thisrequirement.

42. In reexamining this issue, theCommission also notes that the rulescurrently do not indicate that fixeddevice antenna heights must beprovided to the database for use indetermining available channels. It wasclearly the Commissions intent thatfixed devices include their height when



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querying the database because theavailable channels for fixed devicescannot be determined without thisinformation. The Commission istherefore modifying 15.711(b)(3) and15.713(f)(3) to indicate that fixeddevices must submit their antennaheight above ground to the database.

43. The Commission continues to

decline to establish height limits forpersonal/portable devices. As theCommission stated in the Second Reportand Order, there is no practical way toenforce such limits, and such limits arenot necessary due to the differenttechnical and operational characteristicsof personal/portable devices.

Power and Power Spectral DensityLimits

44. In the Second Report and Order,the Commission allowed fixed TV bandsdevices to operate with a peaktransmitter output power of one wattwith a maximum antenna gain of 6 dBi,and required that the transmitter power

be reduced by the same amount in dBthat the maximum antenna gain exceeds6 dBi. This allows unlicensed TV bandsfixed devices to operate with theequivalent of 4 watts EIRP. TheCommission found that 4 watts EIRP issufficient to allow fixed devices tocommunicate at ranges that will servecommunity and rural users whileminimizing the potential forinterference to broadcast television andother authorized services in the TV

bands. Fixed TV bands devices were notpermitted to operate adjacent to

occupied TV channels, although theCommission decided to defer a finaldecision on this issue and to keep therecord open pending the developmentof additional information demonstratingthat a reliable method can be developedto allow adjacent channel operationwhile protecting authorized services.

45. The Commission allowedpersonal/portable TV bands devices tooperate with a peak transmitter outputpower of 100 mW with a maximumantenna gain of 0 dBi, and required thatthe transmitter power of such devices bereduced by the same amount in dB that

the maximum antenna gain exceeds0 dBi. This allows personal/portable TVbands devices to operate with anequivalent of 100 mW EIRP. In caseswhere a personal/portable device isoperating adjacent to an occupied TVchannel, the maximum permitted EIRPis 40 mW. Personal/portable devicesthat rely on spectrum sensing withoutthe use of geo-location and a TV bandsdevice database may be authorized at apower level up to 50 mW EIRP. TheCommission did not specify minimum

bandwidth limits for transmissions by

TV bands devices or power spectraldensity (PSD) limits in the SecondReport and Order.

46. Decision. The Commission is notconvinced by the petitions forreconsideration that the power limits forunlicensed TV bands can be increasedwithout also increasing the potential forinterference to authorized services and

is therefore affirming the power limitsfor fixed and personal/portable devicesthat it adopted in the Second Reportand Order. In addition, the Commissiondoes not find that the power level of TV

bands devices should be restricted toprotect against direct pick-upinterference to cable and satellite TVservices. The Commission does,however, recognize the need to addresspower considerations in TV bandsdevice signals that occupy less than thefull bandwidth of a TV channel and istherefore amending the rules to includepower spectral density limits.

47. The Commission declines toincrease the 4 watt EIRP power limit forfixed devices and notes that it alsoconsidered and rejected a higher powerlimit for fixed devices in the SecondReport and Order. While theCommission previously observed thatthere are advantages to higher powerlevels for fixed devices, such as reducedinfrastructure costs and increasedservice range, it did not adopt a higherpower limit due to concerns aboutincreased risk of interference incongested areas and a lack of experiencewith unlicensed wireless broadbandoperations in the TV bands. The

Commission also recognizes theincreased range provided by operationat higher power levels would beparticularly desirable for someapplications, including rural service andmobile operations as suggested byMotorola. The Commission alsounderstands that there may be situationswhere radio communications facilitiescould operate at higher power in TVwhite spaces without causinginterference. However, the Commissioncontinues to conclude that because theextended range of such devices wouldsignificantly increase the potential for

interference and also make it moredifficult to identify sources ofinterference, it would not be appropriateto allow higher power for unlicensed TV

bands devices at this time. Indeed, suchoperation would be more appropriateunder a licensed regime of regulation.The Commission therefore affirms itsprevious decision on fixed device powerlevels, but could re-visit the issue ofhigher power levels for TV bandsdevices on a licensed or unlicensed

basis at some point in the future as maybe appropriate.

48. The Commission retained thecurrent 100 mW maximum transmitterpower limit for Mode I and Mode IIpersonal/portable devices and decline toestablish a new class of higher powervehicle mounted portable devices. Asthe Commission noted in the SecondReport and Order, personal/portabledevices generally pose a greater risk of

harmful interference to authorizedoperations than fixed devices becausethese devices will change locations,making identification of both unusedTV frequencies and the devicesthemselves, if interference occurs, morecomplex and difficult. The Commissionalso noted the significant distances atwhich interference could occur from apersonal/portable device operating atgreater than 100 mW would make itvery difficult to identify a device that isthe source of interference. TheCommission therefore declines toincrease the power limit for personal/

portable devices at this time.49. Additionally, the Commission isretaining the 50 mW power limit forsensing-only devices. The Commissionstated in the Second Report and Orderthat the prototype TV bands devices ittested were able to sense the presenceof signals from incumbent servicesunder some conditions, but were unableto do so in others, such as in noisyenvironments or in the presence ofstrong adjacent channel signals. Itfurther stated that these factors made itdifficult to fully validate theperformance of sensing technology anddevelop standards to ensure that devices

relying on sensing alone would notcause interference. While theCommission believed that theseproblems could be solved and decidedto permit sensing-only devices, itdecided to limit these devices to 50 mWrather than 100 mW as permitted forother personal/portable devices out ofan abundance of caution with regard totheir interference potential. TheCommission finds that it provided anadequate rationale for the 50 mW powerlimit for sensing-only devices anddeclines to change the power limit forthese devices at this time.

50. The Commission also declines toreduce the maximum permitted powerfor personal/portable devices thatoperate adjacent to occupied TVchannels. In the Second Report andOrder, the Commission recognized thatthere is a potential for TV bands devicesto interfere with TV reception onadjacent channels, but found that suchinterference is unlikely to occur in themajority of situations if the power levelis kept low. As with any interferenceanalysis, certain assumptions weremade concerning factors such as the



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separation distance from the potentialsource of interference to the receiveantenna, the characteristics of thereceiver, the type of transmit andreceive antennas and any interveningterrain or obstacles. The petitioners areessentially challenging the assumptionsthe Commission used in its analysis inthe Second Report and Order. We find

that the Commission made reasonableassumptions and are upholding the40 mW adjacent channel power limit.Specifically, the Commission observesthat interference to TV reception from atransmitter on adjacent channel wouldoccur only when an adjacent channelsignal level is substantially greater thanthe received TV signal level. Thus,adjacent channel interference would bemost likely to occur in weak signal areaswhere an outdoor rooftop antenna isneeded. In such situations, we find theCommissions assumed separationdistance of 16 meters from a TV bands

device to a rooftop TV antenna to bereasonable, as well as its assumptionthat the receive antenna will havehorizontal polarization while the TV

bands device has vertical polarizationand that such a configuration will havea 3 dB polarization mismatch.

51. The Commission agrees that a PSDlimit would help protect authorizedservices in the TV bands and istherefore requiring that the conductedoutput power of fixed and personal/portable TV bands devices comply withPSD limits. In the absence of a PSDlimit, multiple devices with transmit

bandwidths of significantly less than6 megahertz could share a singlechannel, resulting in a total transmittedpower within a channel significantlygreater than the power limits for fixedor personal/portable devices. A PSDlimit will prohibit high powerconcentrations in a single channel,which will reduce the interferencepotential to TV stations and otherservices in the TV bands. TheCommission bases the PSD limit on themaximum permissible conductedoutput power spread across a transmit

bandwidth of 6.0 megahertz, the full

bandwidth of a TV channel. Theresulting conducted PSD limits in a100 kilohertz bandwidth are 16.7 mW(12.2 dBm) for fixed devices, 1.67 mW(2.2 dBm) for personal/portable devices,0.83 mW (0.8 dBm) for sensing-onlypersonal/portable devices and 0.7 mW(1.8 dBm) for personal/portabledevices operating adjacent to occupiedchannels. The Commission adoptedthese PSD limits. The Commissiondeclines, however, to adopt minimum

bandwidth requirements as requested byIEEE 802 and SBE. It finds that a

minimum bandwidth requirement couldunnecessarily constrain the types ofmodulation that could be used with TV

bands devices and is not necessarybecause the PSD limit has the sameeffect of preventing high power levels ina TV channel. The Commission alsoclarified that a device that operatesacross more than one 6 MHz TV channel

is still subject to the maximum powerlimits in 15.709(a)(1) and (a)(2) of therules per channelthe allowable powerper channel does not increase with useof additional bandwidth beyond 6megahertz.

Out of Band Emission (OOBE) Limits

52. In the Second Report and Order,the Commission required that TV bandsdevice emissions in channels adjacentto the occupied channel be attenuated atleast 55 dB below the highest averagepower in the occupied channel.Emission measurements in both theoccupied channel and the adjacentchannels are to be made with aminimum resolution bandwidth of100 kHz and an average detector.

53. Decision. The Commissionmodified the rule for adjacent channelemissions to require that emissions bemeasured relative to the total in-bandpower in a 6 megahertz bandwidth,rather than in a 100 kHz bandwidth.This change will address the concernsraised by petitioners that the measuredin-band power in a narrow bandwidthwill vary depending upon the

bandwidth of the transmitted signal.The Commission will continue to

require that the adjacent channelemissions be measured with a 100 kHz

bandwidth, because a wider bandwidthwould not be able to resolve emissionslocated just outside the channel ofoperation without being affected by thein-band power. The use of a 6 megahertz

bandwidth for measuring the in-bandpower means that a higher reading will

be obtained as compared to using a100 kHz bandwidth, because the wider

bandwidth will capture all the energy ina channel rather than only a portion ofthat energy. The 55 dB attenuation thatthe Commission adopted for adjacent

channel emissions was based on theassumption that identical bandwidthswould be used to measure both in-bandand adjacent channel power, so weagree with IEEE that the currentlyrequired 55 dB attenuation should beincreased to reflect the increased in-

band measuring bandwidth whileproviding the same level of adjacentchannel protection. As noted, theCommission will assume the maximumtransmit bandwidth used to be the full6 MHz channel. We will therefore basethe increase in adjacent channel

attenuation on a bandwidth ratio of6.0 megahertz/100 kHz or 17.8 dB.Thus, the Commission revised therequired adjacent channel attenuation to

be 72.8 dB.54. The Commission declines to

reduce the required adjacent channelattenuation as requested by Motorolaand the Wi-Fi Alliance. Adjacent

channel emissions from a TV bandsdevice appear as co-channel emissionsin an adjacent channel used by a TVstation or other authorized service.Personal/portable TV bands devices arepermitted to operate within theprotected contours of adjacent channelTV stations, and fixed TV bands devicescan operate as close as 0.1 kilometersoutside the contours of adjacent channelstations and at significantly higherpower than personal/portable TV bandsdevices. For these reasons, theCommission finds it necessary to limitadjacent channel emissions to the extent

practicable to prevent interference toadjacent channel TV stations and otherauthorized services. The Commissiondeclines to modify the adjacent channelemissions limits for the VHF band asrequested by Rudman/Erickson becausethey failed to describe or provide ajustification for any specific changes tothe rules.

Direct Pickup Interference

55. In the Second Report and Order,the Commission recognized theconcerns of cable interests regarding thepotential for direct pickup interferenceand their position that power levels

should be limited to a lesser value. Itnoted that FCC staff tests of three digitalcable ready receivers, and anecdotaltests performed by the FCC staff in thelaboratory and field, indicated that thereis some potential for direct pickupinterference to cable service from TV

bands devices. The Commissionobserved that this direct pickupinterference occurred at relatively closedistances within the users premises andcould be corrected by removingconsumer-installed splitters and wiringthat effectively reduce the shielding ofinterfering signals as well as reduce the

desired signal levels available at theusers TV receiver. It also observed thatin the FCC staff tests when just a cableconverter box was used to connectdirectly to the TV receiver, interferencedeclined dramatically and was virtuallynon-existent on the digital tier ofchannels. The Commission furtherobserved in tests by the staff with a 10meter separation between devices onseparate sides of a wall, such as in atownhouse, interference did not occur atundesired signal levels below 100 mWfor two receivers and slightly under 50



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mW for a third. Based upon theseobservations and the fact the TV bandsdevices must incorporate transmitpower control to limit their operatingpower to the minimum necessary forsuccessful communications, theCommission decided that the risk ofdirect pickup interference is notsufficiently great to warrant a reduction

in power that could impede the viabilityof certain TV bands device applications.

56. Decision. The Commissiondeclines to reduce the maximumpermissible power for personal/portabledevices or to impose power andseparation limits for fixed devices asrequested by NCTA and DIRECTV. Itnotes that direct pickup interference isdifferent from interference that can bereceived at the antenna of licensed over-the-air radio services such as broadcasttelevision, low power auxiliary servicesor the PLRMS/CMRS. Interference can

be caused to off-air reception of these

services when an undesired signal onthe same frequency as the transmittedsignal exceeds some threshold at areceiver. By contrast, a cable system orsatellite in-home wiring is a closedsystem in which the operator is notlicensed to transmit on the frequenciesused. No signal is transmitted over-the-air in those applications; rather directpickup interference occurs when anundesired signal leaks into some part ofthe otherwise closed system, such as thecable, connectors, set top box or TV set.Thus, direct pickup interference resultsfrom a lack of immunity to undesiredsignals at some point(s) in the closed

system of wiring and equipment. Asnoted, the Commission has standardsfor regarding the ability of analog cableready TV receivers to reject directpickup interference. However, there areno rules regarding the ability of othercomponents in a system to reject directpickup interference, and selection ofappropriate system components is theowner or cable/satellite TV operatorsresponsibility. In this regard, theCommission generally does not believeit is appropriate to protect theoperations of closed systems that useradiofrequency (RF) signaling from

interference from radio services andoperations that use the airways. In thisregard, the Commission observes thatthe operators/users of such systemshave full discretion to design theirequipment to be immune to ambient RFenergy transmitted by radio systems thatuse the airways.

57. The Commission is not persuadedthat direct pickup interference is asignificant problem as NCTA states. Itstesting revealed many of the samecharacteristics of direct pickupinterference that the Commissions staff

discovered during its testing.Specifically, NCTA determined that thecables in a system are a significantsource of direct pickup and that lowquality (inadequately shielded) cablesand connectors can result insubstantially increased signal ingress. Italso determined that analog systems aresignificantly more sensitive to direct

pickup interference than digitalsystems. The Commission previouslyconsidered these factors when itestablished the power limits for TV

bands devices in the Second Report andOrder. It notes that the NCTA testsassumed a worst case scenario in whichthe cable signal level to a home is at theminimum level required by the rules,the TV bands device operates at themaximum power permitted by the rulesand the maximum signal level isdirected towards a TV receiver. In realworld situations, the cable signal levelmay be greater than the minimum

required, the TV bands device mayoperate at less than the maximum powerdue to the requirement to incorporatetransmit power control, and themaximum TV bands device signal maynot be directed toward a TV receiver,depending on the antenna directivityand orientation. These factors can havea greater impact on the potential fordirect pickup interference than thepower reductions requested by NCTA.The Commission also notes that NCTAstesting showed that some TV receiverscan withstand signals levels greater than100 mW without interference on digitalchannels, even assuming minimum

cable signal input levels. TheCommission further notes that NCTAdid not perform any tests using a cableconverter box, which the Commissionstesting showed, and which NCTAagrees, could further reduce thepotential for direct pickup interference.In any event, notwithstanding NCTAsconcerns for direct pickup interferenceand the possible mitigation of thoseconcerns by elements in rules for TV

bands devices, the Commission finds itinappropriate to limit the utility of TV

bands devices by limiting their power toprotect cable installations with

inadequately shielded wiring or TVreceivers that do not comply with thePart 15 shielding requirements.

TV Bands Database

58. In the Second Report and Order,the Commission required all fixed andMode II TV bands devices to access adatabase to obtain information on theavailable channels at their location andrequired all unlicensed fixed TV bandsdevices to register their operations inthis database. The Commission statedthat it will designate one or more

entities to create and operate the TVbands database(s) and, has invitedinterested parties to apply for selectionas database administrators. Thedatabase(s) will be a privately ownedand operated service that unlicensed TV

bands devices must contact to obtaininformation on channel availability atthe locations where they are operated

and, in the case of fixed devices, toregister their operation at thoselocations. In the case that multipledatabase administrators are selected,each device must contact a databaseservice that the user or the manufacturerof the device selects. Databaseadministrators are permitted to chargefees for registering fixed devices andproviding lists of available channels tofixed devices and personal/portabledevices. A TV bands database will berequired to contain information on: (1)All of the authorized services thatoperate in the TV bands using fixed

transmitters with designated serviceareas, including full service and lowpower TV stations, (2) the service pathsof broadcast auxiliary point-to-pointfacilities, (3) the geographic regionsserved by PLMRS/CMRS operations onchannels 1420, (4) regions served bythe Offshore Radiotelephone Service,and (5) the locations of cable headendsand low power TV receive sites that areoutside the protected contours of the TVstations whose signals they receive. Inaddition, a TV bands database will berequired to contain the locations ofregistered sites where wireless

microphones and other low powerauxiliary devices are used on a regularor scheduled basis. The Commission didnot establish any specific securityrequirements or protocols forcommunications between TV bandsdevices and the TV bands database.

59. The Commission required fixedand Mode II TV bands devices to re-check the database, at a minimum, on adaily basis to provide for timelyprotection of wireless microphones andother new or modified licensedfacilities. If a device fails to makecontact with its database on any given

day, it will be required to ceaseoperating at 11:59 p.m. on the followingday. Mode II devices are also requiredto re-establish their location coordinatesand to access a TV bands database fora list of available channels each timethey are activated or moved. TheCommission further required that, ifmultiple database administrators areauthorized, the database administratorsare to cooperate to develop astandardized process for sharing data ona daily basis or more often, asappropriate, to ensure consistency in



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the records of protected facilities.Finally, the Commission required that adatabase administrator make its servicesavailable to all unlicensed TV bandsdevice users on a non-discriminatory

basis.

Security

60. Decision. On reconsideration, the

Commission found that it is importantand necessary for TV bands devices andTV bands databases to incorporatereasonable and reliable securitymeasures to minimize the possibilitythat TV bands devices will operate onoccupied channels and causeinterference to licensed services, and toprotect the operation of the databasesand the devices they serve from outsidemanipulation. While the Commissiondid not explicitly require theincorporation of security measures inthe Second Report and Order, it notedthat virtually all online transactionsinvolving financial or other confidentialinformation currently use securitymeasures to protect againstunauthorized viewing and/or alterationof information being sent and to ensurethat only authorized users have accessto information. The Commissiontherefore expects that devicemanufacturers and databaseadministrators will have access to and

be able to incorporate the reliability andsecurity measures needed to protect thecontents of databases andcommunications between databases andTV bands devices or other databases.The Commission is concerned that if a

device uses channels provided throughother than legitimate contact with a TV

bands database or if a databaseadministrator does not includeappropriate security to avoid servingunauthorized devices or to preventoutside parties from altering itsprocessing system and data records,there could be interferenceconsequences ranging from mild tosevere.

61. To achieve the necessaryprotection of databases and connections

between devices and databasesregarding channel availability, the

Commission will require that TV bandsdevices and database systems employsecurity measures follows. First, it willrequire that, for purposes of obtaining alist of available channels and relatedmatters, fixed and Mode II TVBDs only

be capable of contacting databasesoperated by administrators designated

by the Commission. This will preventTV bands devices from obtainingchannel lists from unauthorizeddatabases which may be invalid orinaccuratethe Commission isparticularly concerned about potential

cases where a database would indicateas available channels that are used byauthorized services. The Commissionwill also specify that TV bandsdatabases must not provide lists ofavailable channels to uncertified TV

bands devices for purposes of operation(is acceptable for a TV bands databaseto distribute lists of available channels

by means other than contact withTVBDs) in order to avoid facilitating theoperation of unapproved and non-compliant devices. To facilitate theserestrictions, the Commission willrequire that database(s) verify that theFCC identification number (FCC ID)supplied by a fixed or personal/portableTV bands device is for a certifieddevice. To implement this provision,the Commission will also require thatdatabase administrators obtain a list ofcertified TVBDs from its EquipmentAuthorization System.

62. The Commission will furtherrequire that communications betweenTV bands devices and databases betransmitted using secure methods toprevent corruption or unauthorizedmodification of data. This requirementincludes communications of channelavailability and other spectrum accessinformation between fixed and Mode IIdevices (it is not necessary for TVBDs toapply security coding to channelavailability and channel accessinformation that they simply passthrough as such information willalready be protected by the sendingdevice). The Commission will requirethat when Mode I devices communicatewith fixed or Mode II devices forpurposes of obtaining a list of availablechannels, they are to use a securemethod that ensures against corruptionor unauthorized modification of thedata. In addition, a fixed or Mode IIdevice must check with its database thatthe Mode I device has a valid FCCIdentifier before providing a list ofavailable channels. The Commissionwill also require that contactverification signals transmitted forMode I devices be encoded withencryption to secure the identity of thetransmitting device and that Mode Idevices using such signals accept asvalid for authorization only the signalsof the device from which they obtainedtheir list of available channels. Finally,the Commission will require thatdatabases be protected fromunauthorized data input or alteration ofstored data. In order to accomplish thisgoal, the database administrator is toestab

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