The Commission has adopted rules to allow unlicensed radio transmitters to operate in the broadcast television spectrum when that spectrum in not used by a licensed service.The unused spectrum is often referred to as white spaces and can represent a significant amount of unused spectrum in some areas. Subject to certain rules the spectrum may be used for new and innovative products and services.

The Commission is monitoring the development and introduction of these devices and will use this page to support communication of items of interest to the White Space developer community.

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White Space TV Translator Data Entry/Update
Latest Posting

Announces Transfer of Ownership and Control of White Space Database
Wednesday, August 26, 2020
Word: DA-20-904A1.doc
PDF: DA-20-904A1.pdf
Text: DA-20-904A1.txt

White Space TV Translator Data Entry/Update

During the digital television transition many full power stations changed operating channels. Some low power stations also made corresponding operational changes. A significant number of those low power stations have not updated their input channel information in the CDBS database. Input channels for low power stations in this category are not protected if the changes have not been properly recorded in the CDBS. In addition, a number of low power stations receive and retransmit the signals of more than one other TV station and the CDBS does not provide for recording of more than one receive channel. The white space translator input channel update web tool can be used to enter corrected channel/facility and/or multiple receive channel/facility information for the purpose of receiving protection from interference by Television Whites Space (TVWS) devices. The update web tool is available for low power stations use at:

Database Administration

Information regarding TV white space databases, their designated administrators and the Commission’s requirements for their approval and performance is available on this web page.

Please visit the Database Adminstrators Question and Answer page to review related questions that FCC staff have received and answered.

  • 4/17/12
    White Space Database Administrator Group Database-to-Database Synchronization Interoperability Specification Version 1.1.1. PDF

  • 2/14/12
    Presentations given at the TV bands device database administrators meeting on February 14, 2012.
    FCC Presentation: PPT
    Key Bridge Presentation: PPT
    Wireless Microphone Users: PPT
    TVWS Unlicensed Wireless Microphone Data Screens: PDF
    DB to DB Interoperability Demonstration: PDF

  • ▼ Show More....
PLMRS-CMRS Protection Guidance

Protection of Certain T-band (470-512 MHz) PLMRS-CMRS Licenses in the ULS that Authorize Operation Outside of the 13 Designated Major-Market Areas

This is to provide guidance for protecting T-band PLMRS-CMRS operations that are outside of the 13 designated major-market areas from interference from TVWS devices:

The first issue concerns protection of "mobile-only" operations. Such operations are indicated in records where the "HD" table field "corresponding_fixed_location" = NULL. There are two possible situations: 1) there is coordinate information in the "LO" table for the license (indicating that the mobile-only units operate in the local area around that point) and 2) the license specifies separate frequencies for fixed and mobile operation and there is no coordinate information in the table for the mobile operations (indicating that the mobiles do not necessarily operate in a specific area; in such cases use the location of the associated base stations as the coordinate information). In both cases, protection should be provided out to the 54 km and 51 km co-channel and adjacent channel distances for fixed stations (the coordinate information for mobile-only operations is thus to be treated similarly to the coordinate information for a fixed base station).

The second issue concerns licenses for special types of operations such as Special Temporary Authorizations (STA) and developmental (i.e., experimental) licenses. These special licenses are indicated by codes in the "HD" table field "developmental_or_sta":

D = Developmental License
C = Conversion
S = Special Temporary Authorization (STA)
M = Demonstration
N = None of the above

The "C" coded records have been changed (re-coded) to "N", so there should no longer be any "C" records in the ULS database (these records were part of an earlier conversion process). The databases should protect STAs (code "S"), demonstrations (code "M") and regular licensed records (code N"). Do not protect any records that do not have coordinate information in the LO record (mobile-only or otherwise). Taking the above information into account, the records to extract (select) for protection of T-band PLMRS_CMRS licenses that are not in one of the 13 designated major-market areas are those where:

  • radio_service_code from the HD table = "IG, "PW", "YG", "YW", "IK", "YK", or "CD"
  • license_status = "A"
  • corresponding_fixed_location = NULL and there are geographic coordinates in the LO table (in the lat-long DMS fields) (protect the coordinates in the LO table for that entry) or = NOT NULL and there are geographic coordinates in the LO table for the associated fixed station that is indicated by the value in corresponding_fixed_location (protect the coordinates in the LO table for the associated fixed station)*
  • developmental_or_sta = "S", "M" or "N"
  • frequency_assigned =>470 and =<512 from the FR table

* Where the corresponding_fixed_location = NOT NULL, there should not be any coordinates in the LO record for that entry (if there are coordinates present in such records, you should ignore them for processing purposes and refer them to the FCC team to check as data errors). The coordinates for mobile operations associated with a fixed (base) station are those of the associated fixed station.

Waiver Operation

Waivers of the 80 km Limit on Protection of MVPD and Low Power TV Receive Sites

In an Order issued in ET Docket 04-186 on June 1, 2012, the Commission addressed requests for waiver of the provisions in Section 15.712(b) of its rules that limit protection for Multichannel Video Programming Distributors (MVPD), TV translators, low power TV stations and class A TV station receive sites to those located outside of and within 80 km of the service contours of the received stations. In this Order, the Commission granted in part and denied in part requests from eighteen parties to waive Section 15.712(b) of its rules to allow registration in the TV bands databases of certain low power TV and Multichannel Video Program Distributor (MVPD) receive sites that are more than 80 km outside the protected contour of the TV stations that they receive. This Order is available at

TVWS Database Guidelines and Evaluation Requirements

The following documents provide a listing of major requirements used to evaluate TV White space databases.

  • 2/13/12
    Evaluation of TVWS Database Systems for Operation
    Word | Acrobat
  • 2/13/12
    TVWS Database System Requirements and Tests
    Word | Acrobat
  • 9/22/11
    45 day test requirements and plan
    Word | Acrobat
CDBS Data Extraction Logic

OET has developed logic for extraction of records for active TV stations from the Media Bureau’s Consolidated Database System (CDBS). This logic will extract records for U.S. full power TV and low power TV (TV translator, LPTV and Class A) stations and Canadian and Mexican TV stations (all stations from those countries that are in the CDBS – there are no designations for types of Canadian and Mexican stations). The extraction logic document also provides a link to a webpage that contains the code the Commission uses for the subroutines needed to process the various steps in the logic and a link to the CDBS download site.

The Commission will use this logic in extracting data for testing TV white space database systems and evaluating their performance in complying with the rules.We recommend that the TV white space database administrators also use this logic to extract TV stations records from the CDBS for their databases.

We have observed that there may be STA and STAX records in the CDBS that do not have expiration dates. All STAs/STAXs should have expiration dates. If a database encounters STA/STAX records without an expiration date, it should protect those records until such time as an expiration date is added and that date expires (note that if the STA/STAX is deleted the databases should not continue to provide protection to that record). We also ask that a database administrator notify either OET or the Media Bureau if it encounters such records so that we may make appropriate corrections.

  • 3/26/12
    CDBS Data Extraction Information.
    Extraction logic document: [PDF]
    Obtain the extraction code: [Microsoft VB6 Code]
    CDBS download web page: [FTP]
Extraction of Canadian Television Assignment Data

(Updated on 9-24-13)
For purposes of protecting Canadian TV stations (serving locations wholly within Canada) from interference from unlicensed TV bands transmitting devices (TV white space devices), the TV white space database systems are to use Canadian TV station engineering data from Industry Canada’s licensing system rather than the Canadian records in the Commission’s Consolidated Database System (CDBS). (The Canadian station records in the CDBS contain data for internationally coordinated TV station agreements, which may not reflect actual station operations.) Industry Canada’s TV station engineering data for actual operations is placed on the FCC’s website daily using the following procedure and may be obtained by the database systems from the FCC’s website. The data, along with more detailed descriptions, may be obtained using the links below.

Canadian TV Assignment Data Description Document: Word | Acrobat
Download Canadian Television Assignment (CTA) Data

Unlicensed Wireless Microphone Registration Data

Unlicensed Wireless Microphones Venue Registration System Beta Test Presentation.

Unlicensed Wireless Microphones Data Entry System Information.

The instructions for downloading data from the FCC’s system for approving venues that use unlicensed wireless microphones for registration in the TV white space database systems (Unlicensed Wireless Microphone Registration records) are available here for download.
Word | Acrobat

Validation Requirements for Fixed White Space Devices

The requirements for validation of registration requests for fixed white space fixed devices are available for download

Whitespace Q&A

A listing of whitespace related questions and answers is available.
White Space FAQ page