Reading the FCC Tea Leaves

Editor's note: Click here to jump to the summation.

Yesterday's FCC meeting had two items of particular import to wireless microphone users:

  1. Public Notice on the incentive auction for wireless spectrum.
  2. Report and Order 14-165 concerning unlicensed (Part 15) and licensed (Part 74) wireless mic operation in the TV and 600 MHz bands

A third item, Report and Order 14-166, concerning other spectrum bands that wireless mics can operate in, was deleted from the agenda, and was adopted prior to the FCC meeting.

So, what’s an incentive auction and how does it affect wireless mic users?

An incentive auction begins by giving current frequency holders (mostly TV stations) a chance to set the prices that they’d accept to sell off their frequencies, followed by a normal auction of the frequencies that met the sellers‘ reserve price. The end effect will likely be similar to the spectrum auctions that forced wireless microphone users out of the 700 MHz band in 2010, although the “reverse auction” nature of it may have a slightly different effect.

The exact auction specifications are still unknown at the moment, but it’s currently scheduled to start March 29th, 2016 and result in a repacking of TV frequencies in a way that renders large portions of the 600 MHz frequencies off-limits to wireless microphone users. If very successful, it could potentially even end up auctioning frequencies all the way down to below 608 MHz (Lectro Block 23).

So, yeah, that’s not great for wireless microphone users, but the news isn’t all bad. The Middle Class Tax Relief and Job Creation Act of 2012, of all things, provided for continued unlicensed operations under certain circumstances (mostly to be hashed out later.) The hashing out is what’s happening now, but, hey, don’t say congress never did anything for you.

An unlikely alliance of pro audio users and tech companies hoping to use white space devices (WSD, also known as TV band devices) have been discussing it with the FCC (including Gotham’s own Peter Schneider, who explained body-mounted mics and the production process for their edification) and hopefully that informs the final rules.

What did the FCC decide?

Keep in mind that we’ve only seen the press release and the commissioner's statements so far and not the actual reports, so we don’t have all the details. We’ll probably see the actual report within the next week.

Here’s what they flagged about the new rules for licensed users in the press release:

  • Provide more opportunities for licensed use in the remaining TV bands by allowing greater use of the VHF channels and permitting co-channel operations inside DTV contours without coordination if TV signals fall below specified threshold

Licensed wireless mic operation may continue in the low-band VHF spectrum and TV bands where TV stations remain after the auction, although we have no idea at this point how much of the spectrum that will represent.

  • Expand eligibility for licensed use of the 4-megahertz portion of the 600 MHz duplex gap to include all licensed users in the TV bands (broadcasters, cable programming networks, movie studios, and operators at major sporting/concerts/theater venues)

The duplex gap is an 11 MHz buffer that exists between mobile services’ designated spaces for uplinks and downlinks to prevent them from interfering with each other. Licensed wireless mics have been granted access to a 4 MHz portion of that gap. The plan called for that gap to be at the same frequency nationwide, but it’s unknown how that could work, given the different frequency contours of different markets.

The FCC has specifically retained the right to assign TV stations in the duplex gap, so the space within in which wireless microphones can effectively operate will likely be limited in some regions. The auction order suggests that two tv channels may be made available for licensed wireless microphones and unlicensed white space device use in regions where a TV station is operating in the duplex gap, but that’s still a little hazy at this point.

  • Provide new opportunities for these licensed wireless microphones to operate on a secondary basis in three additional spectrum bands, consistent with the Commission’s spectrum management goals – (1) access to significantly more spectrum in the 900 MHz band; (2) access to a portion of the 1435-1525 MHz band at specified times and places, subject to coordination requirements that protect critical aeronautical mobile telemetry; and (3) access to portions of the 6875-7125 MHz band.

Licensed wireless mic operators will be able to use portions of the spectrum in the 900 MHZ, 1435-1525 MHz, and 6875-7125 MHz bands. Obviously, we don’t have the exact parameters yet, but it’s likely the 900 MHZ band space will be 944-952 MHz and possible even a little wider. The 1435-1525 MHz band is used for aviation flight testing and managed by the Aerospace and Flight Test Radio Coordinating Council (AFTRCC) , but is occasionally used for large sporting events that require a lot of frequencies. The permission process to ensure the event isn’t interfering with flight testing is manual at the moment, but would have to be automated by the sound industry (and signed off on by AFTRCC) to be of regular use to productions.

What about unlicensed users?

Unfortunately, the press releases are even more vague on the rules for unlicensed wireless mics. Here are the most specific bits:

  • Provide technical parameters for fixed and personal/portable white space devices to operate in the 600 MHz band, including the duplex gap and guard bands, and channel 37 on a shared non-interference basis with medical telemetry and radio astronomy

Guard bands are the small slices of MHz between bands where low-power devices can operate; the duplex gap is explained above in the licensed microphone use section.

  • Permit sharing of spectrum between white space devices and unlicensed microphones in the 600 MHz band

It’s good that there seems to be defined space where unlicensed microphones can operate, but unfortunately none of the spaces named are set aside for exclusive wireless microphone use, while the permitted operation spectrum for white space devices has been expanded to TV channels where they were previously prohibited.

Given how much additional consideration has been granted to white space devices, it is possible that wireless mic equipment could eventually be required to call into a database to find a clear frequency as white spaces devices must currently. This approach isn’t terribly practical for the film and TV industry where signal interference can often be disastrous and none of the current equipment is equipped with geo-location and database connection functions.

No public mention has been made about the elimination or retention of current FCC procedures which enable unlicensed microphone users to obtain a temporary license or otherwise register for protection in the database

Bottom line it for me.

Become a Part 74 user. The license allows you to reserve channels from white space devices and it’s definitely the way the FCC seems to be pushing the community. Most sound mixers may already qualify for the license under the “producers” definition and qualifications have recently been extended to large sound operations (defined as regularly using at least 50 channels of wireless), opening licensing to rental houses and venues.

It’s not a perfect panacea, but it resolves situations where you know the location in advance, isn’t terribly expensive and helps show the FCC that this is important to the broadcast community. Local 695 has a good guide here.

Prepare for interference with unlicensed wireless mic operation. Unlicensed mic operation looks like it’ll continue to be legal and possible for the foreseeable future, but the protections look like they’re getting less robust. We could still see an exclusive wireless microphone spectrum set-aside from the FCC, but we haven’t so far, and, if it does end up existing, it’s not likely to be very wide. Users who need absolutely reliable unlicensed wireless use may need solutions like auto-switching channels (e.g. Shure’s Axient line) or back-up recordings built-into the transmitter (e.g. Zaxcom wireless).

Don’t panic. We don’t have the final report yet, there’s still another relevant report and order pending, we don’t know how much of the 600 MHz band will be successfully auctioned, and there’s the possibility of additional space on the 5 GHZ band. It’s probably inevitable that you’ll need to trade in or refreq some equipment, but we don’t know how much yet.

We’ll keep you posted when the actual reports emerge and we know more.


Special thanks to Mark Brunner of Shure and Catherine Wang of  Morgan, Lewis & Bockius LLP for their invaluable assistance on this report.

News category: 
In Other News