The NAB told the FCC it should not take further steps towards opening up 6 GHz to unlicensed use at the expense of licensed users before the agency’s “shaky assumptions” are validated by real-world deployments.
“The core legal principle at the center of any proceeding regarding expanded opportunities for unlicensed use is that unlicensed devices are prohibited from causing harmful interference to licensed operations,” NAB told the FCC. The broadcast trade group says it’s “frankly concerned” the Commission appears to be “moving away from this unyielding precedent.”
Broadcasters use portions of the 6 GHz band to support their operations in several ways, including fixed links that deliver content from studios to transmitter sites, mobile transmissions from electronic news gathering trucks deployed to cover live and breaking news and on-site transmissions from portable cameras and microphones to a mobile studio.
“The ongoing COVID-19 pandemic demonstrates how critical this spectrum is to news coverage – not only have broadcasters used 6 GHz links to provide coverage of press conferences and updates from government officials to the public, but also to help enable fully remote newscasts when it became unsafe for broadcasters to be in their studios,” says the trade group in filed comments.
In its Report and Order, the Commission adopted rules permitting unlicensed low power indoor (LPI) devices to operate at 5 dBm/MHz power spectral density EIRP despite substantial concerns broadcasters raised about the significant potential for harmful interference to Broadcast Auxiliary Services.
Time will tell if the Commission was correct in its determination that interference is unlikely to occur, “despite broadcasters’ substantiated concerns that the minimal protections the Report and Order establishes will prove insufficient,” says NAB. It’s “premature” to increase the power levels permitted for LPI operations by an additional 3 dB now when there has been no opportunity to test the Commission’s assumptions in the marketplace, asserts the association.
NAB is similarly concerned about the Further Notice’s proposal to permit very low power operation across the 6 GHz band, indoors and outdoors, with no automatic frequency coordination. None of the mitigation techniques or factors referenced in the Further Notice are likely to protect BAS operations “given the one-way nature of BAS operations,” says NAB.