GS-3: Science and Technology- developments and their applications and effects in everyday life
5G rollout and Aviation Challenge
Context: The rollout of the 5G C-band spectrum (3.7 GHz-3.98 GHz) in the U.S., on January 19, 2022 — led to several major airlines, including Air India, temporarily cancelling their flights to the U.S. over fears of spectrum interference with crucial aircraft navigation systems.
An aircraft type largely affected in this was the Boeing 777.
The two major telecom firms concerned, Verizon and AT&T, also took cognisance of the worries of airlines and agreed to delay 5G deployment around key airports.
How 5G services in Europe and parts of Asia have hardly led to any disruptions to aviation unlike the near panic that has set in the U.S.?
An aviation expert said the main worry is of ‘radio emissions’ at the top of the C-band’s 3.98 GHz frequency ‘bleeding over’ into the 4.2 GHz-4.4 GHz band used by civil aircraft radio altimeters.
USA’s Federal Aviation Administration (FAA) aid that there are differences in the way 5G technology has been deployed in other countries.
These include lower power levels; frequencies that are ‘of a different proximity to frequencies that are used by aviation equipment’ and a different placement of antennas in the vicinity of airports.
In Europe, 5G services are in the 3.4 GHz-3.8 GHz range.
In Korea, they are in the 3.42 GHz-3.7 GHz range.
In U.S. airspace, the initial stages of 5G use will try and mirror the safeguards used in France. But even here, there are differences. In France, for example, the 5G power level (on average, 631 Watts) is still lower than what it would be in the U.S. (on average, 1,585 Watts).
Also the planned buffer zones around airports in the U.S. will protect only the last 20 seconds of the flight.
France also has a condition that the antenna angle has to have a downward tilt to limit potential interference.
The height of a 5G antenna and the power of the signal are the factors that determine how close it can be allowed near an airport or a flight path.
Japanese institute had conducted a study on 5G interference with radio altimeters, which submitted its findings to the International Civil Aviation Organisation (ICAO) in March 2021.
One of the findings was that there would need to be “at least 60 MHz” of what was called a ‘guard band’ to avoid interference with radio altimeters.
It also made a finding of locating the high-power 5G base station 200 metres away from the approach path of an aircraft.
The buffer zones around an estimated 50 U.S. airports will be designed to try and keep 5G signals and aircraft separate.
What has the FAA been doing?
FAA has collaborated with airlines ‘on how they can demonstrate altimeters are safe and reliable in certain 5G C-band environments’.
An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level.
FAA has also issued approvals clearing commercial fleet of airlines to perform low-visibility landings at airports where the 5G C-band is in use.
