The FAA’s 5G Guidance Took the U. S. by Surprise—and Europe

By: Steffen Ring

Global 5G standards help speed next generation wireless network rollout; altimeter makers should consider coordination and publishing their technical standards. 

The November 2 Federal Aviation Administration (FAA) bulletin that 5G transmissions in the 3.7-3.98 MHz band could potentially interfere with flight systems (altimeters) in the 4.2-4.4 MHz band took the European telecom and aviation sectors by surprise. The FAA took this action in conflict with the Federal Communications Commission (FCC), the expert U.S. telecom regulator that studied this issues and designed the rules for 5G deployment in this band. European mobile operators are already using 5G in the same band without reported interference to aviation. Now European regulators must study a problem they did not have before. Had altimeter standards been public, a high school student could assess the compatibility between the highly standardized 5G system and flight systems. To resolve the matter quickly, altimeter makers must publish their product specifications and provide all of the testing data being used to support its position.  A mutual consultation might have mitigated this rift across the pond and an expensive and unnecessary delay in the rollout of 5G in the C-band. 

While Europe has not experienced flight interference from 5G, the FAA’s bulletin has stoked fear. As a result, the European Communications Committee (ECC) and European Conference of Postal and Telecommunications (CEPT) decided to issue an official report and address the aviation systems manufacturers and the European Commission with a view to get the most recent updates of altimeter specifications such that ECC spectrum engineers can investigate the US matter. Fortunately, European 5G systems in the C-band behave exactly as they do in the US because 5G is standardized globally through the Third Generation Partnership Project (3GPP).

Transatlantic Cooperation and Standardization of Aeronautical Devices is needed

Ten years ago, the EU and US signed a Mutual Recognition Agreement (MRA) on the telecommunications sector. The MRA facilitates industry and authorities to recognize and approve technical parameters and measurement results developed by each other’s laboratories. This has helped to speed technology trust building and expedite regulatory measures on both sides of the Atlantic. We should push for an MRA on the aeronautical electronics sector to obtain much faster and more credible exchange of vital engineering parameters and a smooth resolution of conflicts.

The de jure standards for mobile wireless technologies are powerfully developed and promoted through 3GPP, where the technology experts from around the world come together to write the technical specifications for new products and services. The US is in 3GPP represented by the Alliance for Telecommunications Industry Solutions (ATIS); Europe by the European Telecommunications Standards Institute (ETSI). 3GPP is open for anyone to find the technical specifications for 5G and assess potential interference scenarios with 5G involved.  Had we had similar official technical standards for altimeters, this situation with alleged unknown device characteristics and the subsequently raised potential flight safety issues could have been resolved very fast—or perhaps avoided all together in the first place.

About the Author:

Steffen Ring is the CEO and owner of Ring Advocacy LLC, ( ), which he inaugurated in 2015 after retirement from Motorola Inc. (now Motorola Solutions Inc.). The corporation is registered in the European Union (Denmark) and serve clients globally.

Ring served for Motorola Inc. as spectrum, standards and regulatory expert for 39 years, the last 10 years as officer in the Global Government Affairs dept., Washington D.C. 

Ring is inter alia specializing in mission critical radio systems and one of the first chairmen in the ETSI Project TETRA, where the globally accepted TETRA standard was developed from the early ‘90. He also worked close with the NATO HQ in Brussels in order to promote a civil-military spectrum sharing agreement (signed in Ottawa 1994) for public safety authorities’ access to the band 380 – 400 MHz for TETRA in NATO Nations, except the US. Later the TETRA standard was also introduced in the US market, alongside the P25 standard for Public Safety.