Opposition to 5G deployment is increasing worldwide due to numerous significant issues associated with it. This has limited, slowed, and/or stopped activation in some locations including again recently near U.S. airports due to unresolved aviation risks. The Federal Communications Commission (FCC) is supposed to protect Americans from the telecom industry but has instead catered to it for decades (see 1, 2). This has led to several lawsuits filed against it as well as well-documented complaints made by lawmakers, other government agencies, and consumer, corporate, cybersecurity, environmental, energy, health, and trade organizations. In regard to controversial 5G technology, recently, FCC Chairwoman, Jessica Rosenworcel, said that the agency needs to “rethink our approach to spectrum policy and move beyond just transmitters and consider receivers, too.” Of course, the Consumer Technology Association (CTA) has objected to this so only time will tell if the FCC will actually provide sufficient safeguards on transmitters and/or receivers. Additionally, at least one airlines group maintains that retrofitting airplanes’ altimeters with 5G filters won’t eliminate dangerous interference issues.
The Federal Aviation Administration says it finally has a plan for the industry to replace or retrofit airplane altimeters that can’t filter out transmissions from outside their allotted frequencies. The altimeter problem has prevented AT&T and Verizon from fully deploying 5G on the C-Band spectrum licenses the wireless carriers purchased for a combined $69 billion.
The FAA was urging airlines to retrofit or replace altimeters in recent months and now says it has finalized a plan. An FAA statement on Friday said that “airlines and other operators of aircraft equipped with the affected radio altimeters must install filters or other enhancements as soon as possible.”
AT&T and Verizon said they will be able to accelerate 5G deployments near airports in the coming months, but the carriers agreed to continue some level of “voluntary mitigations” in the airport areas until July 2023.
Altimeters are used by airplanes to measure altitude. The FAA said a new “phased approach requires operators of regional aircraft with radio altimeters most susceptible to interference to retrofit them with radio frequency filters by the end of 2022. This work has already begun and will continue on an expedited basis.”
Filters can be installed in a few hours
Additionally, “filters and replacement units for the mainline commercial fleet should be available on a schedule that would permit the work to be largely completed by July 2023,” the FAA said, continuing:
The radio-altimeter manufacturers have worked at an unprecedented pace with Embraer, Boeing, Airbus and Mitsubishi Heavy Industries to develop and test filters and installation kits for these aircraft. Customers are receiving the first kits now. In most cases, the kits can be installed in a few hours at airline maintenance facilities.
Throughout this process, the FAA will work with both industries to track the pace of the radio altimeter retrofits while also working with the wireless companies to relax mitigations around key airports in carefully considered phases.
FCC said 220 MHz guard band should be enough
The Federal Communications Commission in February 2020 approved mobile use in the C-Band, specifically from 3.7 to 3.98 GHz. As airplane altimeters rely on a spectrum from 4.2 GHz to 4.4 GHz, this left a 220 MHz guard band to protect altimeters from 5G transmissions.
The FCC found that harmful interference to altimeters was unlikely to occur “under reasonable scenarios” given the size of the guard band and power limits the FCC required for C-Band transmissions. The FCC also urged the aviation industry to conduct more research “on why there may even be a potential for some interference given that well-designed equipment should not ordinarily receive any significant interference (let alone harmful interference) given these circumstances.”
The FAA and aviation industry were nonetheless unprepared for the C-Band launches originally scheduled to begin in December 2021. AT&T and Verizon agreed to a nationwide delay for about six weeks and to limits on deployment near airports until mid-2022. The carriers last week agreed to keep some restrictions near airports in place for another 12 months.
“During initial negotiations in January, the wireless companies offered to keep mitigations in place until July 5, 2022, while they worked with the FAA to better understand the effects of 5G C-band signals on sensitive aviation instruments,” the FAA said Friday. “Based on progress achieved during a series of stakeholder roundtable meetings, the wireless companies offered Friday to continue with some level of voluntary mitigations for another year.”
Carriers are satisfied‚ but airlines object
Verizon said the latest development will let it “make full use of our C-Band spectrum for 5G around airports on an accelerated and defined schedule. Under this agreement reached with the FAA, we will lift the voluntary limitations on our 5G network deployment around airports in a staged approach over the coming months meaning even more consumers and businesses will benefit from the tremendous capabilities of 5G technology.” Verizon said the deal “is the result of months of close collaboration with the FAA, FCC, and aviation industry.”
AT&T said that “close coordination with the FAA over the last several months” has helped the carrier develop “a more tailored approach to controlling signal strength around runways that allows us to activate more towers and increase signal strength.”