How wireless audio copes with shrinking RF spectrum

Professional wireless audio in the U.S. has been losing radio spectrum for about thirty years. The FCC auctioned the 700 MHz band, once used for analog TV, in the 2000s and then the 600 MHz range in the following decade, both mainly for mobile networks. At the same time phones, Wi-Fi and other wireless devices have multiplied. Broadcast audio teams, from sideline reporters' microphones to large intercom systems at drafts and championship games, now have to fit more signals into less space. An overview published in February 2026 described two responses: working with regulators and finding engineering workarounds.

WMAS and dynamic allocation

The newest workaround is WMAS (Wireless Multichannel Audio Systems). Instead of giving each microphone its own narrow frequency, a WMAS system packs many audio channels into one wideband RF channel. The technology and the matching FCC rule change took more than ten years to develop.

Sennheiser builds its Spectera ecosystem on it: microphones, IFB and control data, up to 64 channels (32 in, 32 out), share one 6 or 8 MHz TV-channel width. Joe Ciaudelli, the company's director of spectrum and innovation, said Spectera has dynamic resource allocation (DRA) built in, which shifts bandwidth in real time, for example toward a reporter moving around a stadium and away from a fixed source. Shure uses WMAS in a narrower way. Jason Waufle of Shure said narrowband digital systems are still often the better fit when five to seven different parties share the airwaves at one sporting event.

Ultra-wideband and power control

Jackie Green, director at Nexonic and an advisor to the UWB Alliance, pointed to Ultra-Wide Band. It is a short-range, low-power technology that uses 500 MHz of bandwidth and trades range for performance. Because its signals reach only a short distance, the same frequencies can be reused by devices that are physically apart, which suits near-field uses such as a reporter's microphone. Green also warned that new 5G deployments in auctioned bands can raise interference risks.

The regulatory route

Ciaudelli said users have pushed regulators to open the middle of the 900 MHz range and that access to the 1435-1525 MHz band, coordinated in the U.S. by AFTRCC, will soon work through an electronic key instead of special temporary authorizations. Sennheiser planned new products for that band in February. Shure set up the Wireless Microphone Spectrum Alliance in 2025; it has more than 60 corporate members, and its plans include interference tests in the 1.2 GHz range and work on TV channel 37 (608-614 MHz). Waufle said a coalition carries more weight with the FCC or CEPT than one company alone.