Rosenworcel says FCC is carefully analyzing interference risk in 12 GHz band

While attention is centered on the FCC’s rejection of Starlink’s RDOF application, FCC Chairwoman Jessica Rosenworcel on Wednesday responded to a Republican senator’s concerns about the ongoing 12 GHz proceeding.

Starlink is at the center of the 12 GHz debate in that its parent company, SpaceX, insists the spectrum is necessary for Starlink to survive. Thousands of comments were submitted to the FCC  in support of Starlink and its use of the 12 GHz band, a move that the 5G for 12 GHz Coalition said was part of a “misinformation campaign.”

U.S. Representative Neal Dunn, R-Florida, wrote a letter to Chairwoman Rosenworcel on July 8 expressing his concern about the 12 GHz band and the need to protect U.S. companies that have invested billions of dollars in non-geostationary (NGSO) satellite systems to provide high-speed broadband to Americans.

In a letter dated August 10, Chairwoman Rosenworcel discussed how the commission is evaluating two potential approaches to future use of the 12 GHz band: increasing terrestrial use of the shared band or continuing with the current framework.

“This will require carefully examining the characteristics of this spectrum band—including its propagation and capacity characteristics, the nature of in-band and adjacent band incumbent use, and the potential for international harmonization—before deciding whether, and if so, how, to make it available for more intensive terrestrial or satellite use,” Rosenworcel wrote.

She noted that it’s a “complex engineering process that involves analyzing competing technical analyses.”

For example, the agency is considering the criteria that should be used for assessing interference between mobile and satellite services. That’s important, she said, because one study in the record points to an interference-to-noise ratio based on an ITU-R specification that applies to terrestrial and satellite interference, while others advocate for a more stringent threshold that some satellite systems are required to use to coordinate among themselves under FCC rules.

Furthermore, “we are determining what propagation model should be used to assess how the radiofrequency energy from 5G transmitters will travel and dissipate in rural, suburban, urban, and dense urban environments. In our record, some parties point to a 3GPP model, while others assert that an ITU-R specification is more appropriate,” she said. “A wide range of legal, technical, and policy experts from the FCC’s Wireless Telecommunications Bureau, International Bureau, and Office of Engineering and Technology are engaged in this review and coordinating, as necessary, with other federal authorities in the process.”

Her comments are along the same lines as statements she made previously about the complex nature of current users of the band and the potential for adding new users. Historically, the band was used for Direct Broadcast Satellite (DBS) service and Multi-Channel Video and Data Distribution Service (MVDDS). More recently, new satellite operations received authorization to use the band.

Dish Network, which holds licenses in the band, has been advocating for rule changes that would allow it to use the spectrum for 5G. Similarly, RS Access, which is tied to Dell Technologies founder and CEO Michael Dell, has been pushing for change that would open the band up to 5G, which is the exact opposite of what SpaceX and Starlink want.

RS Access CEO V. Noah Campbell said he’s encouraged by the chairwoman’s latest assessment.

“We’re encouraged by Chairwoman Rosenworcel’s letter and commitment to letting science and engineering guide the commission’s work,” Campbell said in a statement provided to Fierce. “This sentiment has been echoed repeatedly by other commissioners and FCC staff, and we look forward to our ongoing engagement with each of the bureaus as they review the record. We’re confident in the analysis we’ve submitted to date and believe a win-win scenario can be achieved to meet the explosive demand for 5G spectrum with minimal to no impact on satellite services.”