AT&T and Verizon said they will reduce the power of their C-band 5G transmissions slightly in six months. The companies said they will do so to give federal aviation officials more time to study how such a transmission could affect radio altimeters in aircraft.
“We are committed to the rapid rollout of 5G and aviation security,” the two companies told the FCC in a new letter. “While we continue to believe that the FCC’s current rules allow for both, we will, without waiving our legal rights associated with our significant investments in these licenses, adopt these measures to allow further time for further analysis. . ”
Importantly, according to the Wall Street Journal, leaders in the wireless industry do not expect the power reduction to “seriously impair” operators’ 5G operation in the spectrum band.
Furthermore, operators continued to argue that their C-band 5G transmissions do not pose a risk to US air travel, despite a report from some airlines showing a potential risk of flight interference.
“Yes, the RTCA report, which is the primary basis for the FAAs and the RA [radio altimeter] stakeholders ?? erroneous allegations of harmful interference ?? has been thoroughly refuted and consistently rejected by regulators across the globe, “wrote AT&T and Verizon. to combine multiple worst-case inputs, create unlikely test scenarios and use extreme test standards. ”
Nevertheless, AT&T and Verizon agreed to reduce the power levels of their nationwide C-band operations and to further adjust their operations close to airports for a period of six months until 6 July. They have previously agreed to postpone their C-band network launch for a month, until January, due to the issue.
The power reduction details are for hardcore RF engineers only: “Limit the C-band effective isotropic radiated power (EIRP) across the horizon of all 5G base stations to no more than the minimum of: (a) 62 dBm / MHz or (b) 48 + 20 × log10 (1 / sin (Ɵ)) dBm / MHz, where Ɵ is the elevation angle above the horizontal plane of the base station’s antennas, “the companies wrote. “Limit C-band EIRP below the horizon of all 5G base stations to no more than 62 dBm / MHz.”
The problem is noteworthy given that AT&T and Verizon are hoping to offer new, fast-paced 5G services on the C-band spectrum licenses they spent billions of dollars on buying at an FCC auction earlier this year.
?? Mike Dano, Editor-in-Chief, 5G & Mobile Strategies, Light Reading | @mikeddano