France does not encounter the same bazaar as in the United States between 5G and aviation. A calm which is explained by several measures taken upstream, as a precaution.
This is a situation that, in the United States, is surprising: how is it that Europe does not encounter at all the same problems of cohabitation between 5G and aviation, while the heavyweights of the aviation sector and the big mobile phone operators seem to be at loggerheads in the land of Uncle Sam? What went wrong?
The gap between the two shores of the Atlantic is such that CNN even headlined an article in its January 19, 2022 edition: “ Europe has rolled out 5G without harming aviation. here’s how “. And the subject is more specifically interested in France, which has not since encountered any case of interference between an aircraft and 5G, according to an official interviewed by the American channel.
No major concern between planes and 5G in France
The explanation is that France has decided to apply several cumulative measures to limit the circumstances in which 5G wave emissions disturb radio altimeters. It is in fact above all the protection of this system that matters, because its role is crucial for the crew during the landing phases, in particular in bad weather.
Radio altimeters are devices that use radio waves to calculate the altitude of the aircraft relative to the ground (or relative to a body of water). They are found in both airplanes and helicopters. When visibility is degraded, these devices help to estimate the distance from the runway and therefore, if the trajectory is consistent.
It is with these considerations in mind that a more restrictive protocol for operators has been put in place, even if it means delaying the deployment of 5G in and near airports, heliports and hospitals (which may have a helipad). Broadly, we can distinguish three key provisions that have avoided a mess like in the USA.
First, the difference between the disputed frequencies. It is greater in France between the frequencies of the radio altimeters and those for 5G, which reduces the overlap of the waves between them and, therefore, the interference. The margin is 400 MHz in France, against 200 MHz in the USA. This space serves as a buffer zone between the two blocks of frequencies.
In addition to this spacing, there is a safety protocol, defined by the authorities, which imposes several rules of caution on operators. The first is that they need to direct the signals from the 5G antennas downwards, at least for installations that are close to places recording significant aerial activity.
This instruction is mentioned in a technical note from the National Frequency Agency. This document, it is said, specifies the ” definition of safety and precautionary zones around airport runways, in addition to the prohibition for 5G operators to direct their beams upwards “. It also contains other guidelines.
Thus, the authorities’ relatively conservative approach to the cohabitation between 5G and aircraft has resulted in the creation of two perimeters around airports: the first is called a “security zone”, while the second is a “precautionary zone”. “. In these spaces, the location of the antennas is supervised and their power limited.
Gap between waves, downward facing signals, perimeters around airports…
” Antennas around 17 major French airports must be angled away from flight paths to minimize the risk of interference “, Confirmed an official of the National Frequency Agency to CNN. The role of the agency is to ensure that all the waves coexist without concern and, if necessary, it intervenes in cases of jamming and interference.
Other choices, specific to the United States, are also called into question. ” We were not aware that the power of the antennas in the United States [avait] been doubled compared to what is happening elsewhere “Complained Tim Clark, the boss of Emirates, on American television. This extra power is not found elsewhere, at least not in France.
On the contrary, it is rather the opposite case that is observed: operators must, for example, act ” to avoid configurations where grating lobes appear in the active antennas “. Array lobes are a phenomenon that has the particularity of dispersing a significant part of the antenna’s power upwards.
Last notable action that can be mentioned: the replacement of the oldest altimeters, to trade them against more modern and better protected devices. Le Parisien indicates that renewals are underway in Europe, but also in the United States. There are two per plane. However, this technical update is not always necessary.
