Sennheiser Celebrates Recently Enacted FCC Regulations in Wireless Microphone Technology

The Federal Communications Commission (FCC) has adopted new rules for Wireless Multichannel Audio Systems (WMAS) in the United States, marking a significant milestone in the professional audio industry. This technology, expected to revolutionize the sector, has been under development for over a decade by an unnamed company, which filed a Petition for Rulemaking with the FCC in August 2018 to change the bandwidth for WMAS frequencies.

Traditional wireless microphones are limited to an RF bandwidth of 200 kHz. However, WMAS offers a substantial improvement, providing higher spectral efficiency compared to conventional systems. This technology multiplexes audio channels onto a wideband RF channel, which is 6 MHz for the United States.

One of the key advantages of WMAS is its superior protection to nearby operators of other wireless devices. The elimination of intermodulation products in WMAS allows in-ear monitor channels to use the same block of RF spectrum as wireless microphones, thereby reducing interference.

Conventional wireless microphones, with multiple carriers, are prone to generating non-harmonic distortion products, known as intermodulation (IM), which can interfere with wanted signals. Each transmitter in these systems continuously outputs power, typically 50 mW, which raises the RF noise floor with each channel added. In contrast, WMAS employs portable bidirectional transceivers that communicate with a base station at an extremely low power spectral density.

Joe Ciaudelli, director of spectrum and innovation for Sennheiser, expressed gratitude to the FCC's Office of Engineering & Technology (OET) for their careful study of WMAS claims and supporting evidence. He also noted that WMAS technology is expected to further enhance spectral efficiency.

Perhaps the most exciting development is that Sennheiser's WMAS will allow for the first time a single pack to be both a transmitter and an in-ear monitor receiver. This innovation could significantly streamline equipment for live performance and studio applications, where WMAS is designed to fulfill the Commission's goals of greater spectrum efficiency and sharing compatibility.

The new rules for WMAS also provide greater interference protection to other wireless services that share the same spectrum. This is a significant step towards ensuring the coexistence of various wireless technologies in the increasingly crowded radio frequency (RF) landscape.

As the professional audio industry eagerly awaits the implementation of WMAS, it's clear that this technology is poised to redefine the way we handle wireless audio in live performances and studio settings. The future of wireless audio is here, and it's more efficient, more protective, and more versatile than ever before.

Sennheiser Celebrates Recently Enacted FCC Regulations in Wireless Microphone Technology