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What the WMAS Ruling Means for Radio

The FCC decision takes us closer to having more options, innovations and flexibility

The author is global head of spectrum & regulatory affairs for Shure.

Prakash Moorut

Today, countless wireless services are vying for space on the open airwaves. Ensuring that these services operate at the same time without interference is no easy feat.

One very sizeable user of the airwaves is wireless microphones. While the average person may not notice them, they are relied upon daily, everywhere from corporate presentations and news reporting to cultural happenings — e.g., theater, music, sporting events, education — and more. 

The rules for operating wireless microphones must become more efficient and effective for all parties involved.

Wireless Multichannel Audio Systems, a new, scalable wireless technology, ensure more effective use of the airwaves by enabling increased wireless microphones and in-ear monitoring systems to operate in limited spectrum.

A recent FCC ruling — supported by leading industry audio manufacturers like Shure — will allow WMAS technology to operate in various spectrum bands, including VHF and UHF TV bands, expanding the opportunities and applications available to wireless microphone users.

What is WMAS?

Wireless Multichannel Audio Systems utilize broadband digital transmission techniques that operate with wider bandwidths than legacy systems and comply with the European Telecommunications Standards Institute (ETSI) standard. It is already approved and integrated within European markets, and it is becoming more apparent in the United States.

Initially, WMAS aims at expanding the wireless frequencies legacy systems use to more users. We could envisage that in the future WMAS could get access to new bands. 

For nearly 100 years, Shure has focused on innovating with solutions that address customer needs while simultaneously advocating for the improvement and availability of spectrum. WMAS offers users scalability and simplification of device deployment, ensuring fast setup and efficient spectrum utilization. 

Users of wireless systems vie for frequency space for live event production.

The ruling

The new FCC ruling allows the operation and deployment of more spectrally efficient wireless microphone technology across the U.S. It also increases flexibility for the millions of microphone users and will benefit individuals, large organizations, and small businesses alike — here’s why:

  • Expands the Space — The new FCC ruling permits both licensed and unlicensed users to leverage WMAS technology and spectrum. With unlicensed users far exceeding licensed ones, this ruling will greatly expand the market size. 
  • Increases Scalability — By highlighting the need for the 100 mW unlicensed power, the ruling allows providers to minimize the occupied spectrum only to what’s needed and available while keeping the same level of performance to narrowband. This decreases total Power Spectral Density (PSD), which aligns with recent updates to WMAS within ETSI.
  • Keeps Existing Standards — For current users of narrowband wireless microphone equipment, their rights and usage expectations will remain unchanged. Ultimately, the PSD for WMAS will be lower than a single narrowband wireless microphone. This will decrease the potential for harmful interference in the bands where they operate.
  • Enhances Spectral Efficiency — WMAS is required to have an operational mode capable of providing at least three audio channels per megahertz, even if it is not required to operate within a specific minimum number of channels.

Ultimately, the FCC is leveraging this improved technology to enhance the efficiency of wireless microphone usage and the spectrum generally. 

Positive impact

The decision to allow unlicensed WMAS with power up to 100 mW will be highly beneficial to audio professionals across the country. This rule change allows users to operate without the worry or need to go through the complicated licensing process.

The new WMAS regulations will enable manufacturers, like Shure, to develop innovative products with a focus on improved spectral efficiency, scalable audio services and simplified deployment — e.g., permitting multiple wireless audio units to transmit over one wideband channel without interference. It also allows customers access to quality audio in ever-changing landscapes and opens the door to new usage applications as WMAS will drive increased innovation in the wireless spectrum and with wireless microphone technologies due to its wideband nature, higher power, and more. Ultimately, there is so much untapped potential that is yet to be explored. 

Wireless microphones play a pivotal role in American life. This ruling is one step closer to providing users across the U.S. with more options, innovations and flexibility. Shure will continue to play an active role with governing bodies to advocate on behalf of the many who rely on wireless microphones both in the U.S. and across the globe.

[Read past Radio World articles on the topic of WMAS.]