Wireless microphones are used to transmit sound to an amplifier or recording device without need of a physical cable. Their use provides many important functions that serve the public interest. For instance, they play an essential role in enabling broadcasters and other video programming networks to serve consumers, including helping electronic news gathering (ENG) activities at locations in the field and the broadcasting of live sports events. Wireless microphone users include theaters and music venues, film studios, conventions, corporate events, houses of worship, major sports leagues, and schools. Wireless microphones can include hand-held or body-worn wireless microphones, in-ear monitors, devices used for cueing on-air talent, and intercom systems for backstage communications.
There are a wide number of wireless microphones available, serving different needs. Some meet high technical standards to achieve the performance purposes for which they are used, while others do not require such high-end technical capabilities for their particular purposes. Wireless microphones may operate in various different spectrum bands. The technical rules under which wireless microphones operate will differ depending on the spectrum band in which they operate. Wireless microphones may be designed to operate on a discrete set of frequencies within a spectrum band, or they may cover an entire range of frequencies in the band.
The FCC allows the use of wireless microphones on a licensed and unlicensed basis, depending on the spectrum band. Most wireless microphones that operate today use spectrum in the current TV bands (TV channels 2 to 51, except channel 37), though an increasing number operate on other spectrum bands. The amount of spectrum in the TV bands available for wireless microphones will decrease following the incentive auction because a portion of the TV band spectrum – the 600 MHz Band – will be repurposed in the future for new wireless services, and that repurposed spectrum will not continue to be available for wireless microphone use. In 2014, the FCC initiated a rulemaking proceeding to assess options to meet the ongoing needs of wireless microphone users, including potentially making additional spectrum bands available for their use. In the Notice of Proposed rulemaking in that that proceeding, FCC 14-145, it also is examining what steps to take to provide for a smooth transition for wireless microphones from the repurposed 600 MHz Band to other spectrum.
Types of Wireless Microphone Operations Authorized by the FCC – Licensed and Unlicensed
Licensed Wireless Microphones.Wireless microphone users and users of other similar equipment (such as for cue and control communications and synchronization of TV camera signals) may obtain low power auxiliary station (LPAS) licenses under Part 74, Subpart H, of the FCC’s rules, to operate on TV band spectrum subject to certain prohibitions and other requirements contained in the rules. The FCC’s rules generally permit licensed wireless microphones operations on unused television channels, but they must share this spectrum with other users and they have a secondary status, which means they must protect the primary TV broadcast operations from harmful interference and must accept interference from primary users when they are operating.
Wireless microphone users that are eligible for a Part 74 license include broadcasters and motion picture and television program production entities. In 2014, the FCC expanded eligibility for wireless microphone licenses by adding two new categories of eligible entities: “large venue owner or operator” and “professional sound company.” To be eligible for a license under these new categories, a large venue owner or operator and a professional sound company must routinely use 50 or more LPAS devices, where the use of such devices is an integral part of major events or productions. “Routinely using” 50 or more LPAS devices means that the venue owner or operator uses 50 or more such devices for most events or productions. FCC 14-62
Wireless microphone users may also operate on a licensed basis in other spectrum bands, including the 944-952 MHz Band under Part 74, where eligibility is limited generally to broadcasters and broadcast network entities, and on certain frequencies in the 169-172 MHz Band, which is available to a variety of entities that are subject to rules that include the use of relatively narrow bandwidth.
Unlicensed Wireless Microphones.Many if not most wireless microphone users today operate on an unlicensed basis in the TV band spectrum. The unlicensed use of wireless microphones in TV band spectrum is subject to certain restrictions, including that they generally be operated at a lower power than by users that have a license for operating wireless microphones under Part 74, they may not cause harmful interference, and they must accept any interference from other users that operate in the band. The FCC has sought public comment on adopting rules for the operation of unlicensed wireless microphones in the TV band spectrum in a Notice of Proposed Rulemaking in FCC 14-144. Also, wireless microphones have been developed that operate on other frequency bands on an unlicensed basis under the FCC’s Part 15 rules. These frequency bands include the 902-928 MHz band, the 1920-1930 MHz band, and the 2.4 GHz band.
Wireless Microphone Operations and Prohibitions
600 MHz Band.In the May 2014 Incentive Auction Report and Order, the FCC adopted rules to implement the broadcast television spectrum incentive auction, which will involve reorganizing the existing television band and repurposing a portion of the UHF television band for new wireless broadband services, which will no longer be available to wireless microphones. This repurposing of the 600 MHz spectrum will, therefore, affect wireless microphone operations across the current TV bands in the future. Until the incentive auction involving this TV band spectrum is completed and the FCC issues a channel reassignment Public Notice establishing the final 600 MHz Band plan, the impact of repurposing on wireless microphones will not be known because the specific UHF frequencies that are being repurposed for wireless services and no longer available for wireless microphones will not be known.
The FCC has provided for a multi-year period to help smooth the transition as wireless microphone operators obtain new equipment and transition out of the repurposed 600 MHz band to other spectrum. During the transition period, these operators may continue to access the 600 MHz Band spectrum, but will operate on a secondary basis to the new 600 MHz licensees and must not cause interference to and must accept harmful interference from those licensees. The transition period will end 39 months after the issuance of the channel reassignment Public Notice, at which time all wireless microphone and other LPAS users must cease operations on the repurposed 600 MHz Band frequencies. The FCC is considering what steps to take for a smooth transition of wireless microphones out of the 600 MHz Band. FCC 14-145
The FCC is exploring steps to address wireless microphone users’ long-term needs, including potentially accessing spectrum in additional spectrum bands. In a Notice of Proposed Rulemaking in FCC 14-145, the FCC is examining other spectrum bands where wireless microphones currently operate as well as proposals for authorizing wireless microphones in additional spectrum bands. FCC 14-145In a separate Notice of Proposed Rulemaking in FCC 14-144, the FCC is addressing issues that include the operation of unlicensed white space devices, unlicensed wireless microphones and wireless microphones licensed under Part 74, while protecting authorized licensed service from harmful interference.
700 MHz Band.The FCC prohibits the operation of wireless microphones and similar devices (e.g., wireless intercoms, wireless in-ear monitors, wireless audio instrument links, and wireless cueing equipment) in the 700 MHz Band, i.e., 698 - 806 MHz. This 700 MHz band formerly had been allocated for TV broadcast services, and has been repurposed for wireless broadband and public safety services. The manufacture, import, sale, lease, offer for sale or lease, or shipment of wireless microphones or similar devices intended for use in the United States in the 700 MHz Band was banned by the FCC in January 2010, and use of the devices in the 700 MHz Band also was prohibited as of June 12, 2010. Refer to the materials available in the link below for further information on these prohibitions. Wireless Microphones Prohibited 700MHz Band
Registration of Wireless Microphones
The FCC’s rules provide for interference protection for certain wireless microphone operations in the TV bands spectrum by permitting qualifying operations to register in a database administered by one or more third parties. Under the current rules, licensed wireless microphone users and user of other LPAS equipment may register their operating locations, channels and times in the white spaces database, and receive protection from unlicensed TV band devices.
Parties operating large numbers of wireless microphones on an unlicensed basis are also allowed to register their operations for protection through the database under certain circumstances. Registration of unlicensed wireless microphones is limited to venues of events and productions and shows that use large numbers of wireless microphones that cannot be accommodated in the channels that are not available for use by white space devices at a specified location.
The FCC currently designates two unused TV channels, where available, for wireless microphone operations and they are not made available for unlicensed TV band devices. Following the incentive auction, these two channels will no longer be designated exclusively for wireless microphones following the repacking of the TV bands. Also, in a Notice of Proposed Rulemaking FCC 14-144, the FCC is examining database registration procedures, and has proposed to eliminate the rule that permits unlicensed wireless microphone users to register their operations in the white spaces database. In the same proceeding, the FCC is considering other ways that unlicensed wireless microphones would operate on an equal basis with white space devices in the TV bands, the 600 MHz guard bands, and the portion of the duplex gap where unlicensed operations are allowed.
For help on registration see [Steps to Register Unlicensed LPADs (Including Wireless Microphones) In the Universal Licensing System (ULS) ]
Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz BandOrder - Acrobat - Word
Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806MHz BandErratum - Acrobat
Report and Order and Further NPRM - Acrobat - Word
Statement of Chairman Genachowski - Acrobat - Word