The proliferation of these flying objects worries the authorities. Army, industrialists and start-ups are looking for solutions.
The false assault on the Bugey nuclear power plant by Greenpeace (July 3, 2018) over Fort Brégançon (July 6), where Emmanuel Macron was spending his holidays, going through the attack of Venezuelan President, Nicolas Maduro, during speech (August 4), or the disruption of air traffic due to intrusions into airports, the use of drones for malicious purposes is spreading. A new danger from heaven? “The threat is protean and has various levels of seriousness – from privacy to terrorist risk,” says Henry de Plinval, director of the drones program at the National Office for Aeronautical Studies and Research (Onera).
READ ALSO >> Interview with Generals Jean-Christophe Zimmermann and Étienne Patry on Anti-UAV
To protect themselves, the public authorities and the big companies are struggling. “The security of the airspace can be schematized in three acts”, explains Henry de Plinval. Detection, that is, 24-hour surveillance of a given site and the triggering of an intrusion alert; identification, to confirm and qualify the threat – is it a simple shooting, espionage or even a terrorist action? – then to locate the device or the pilot; finally the neutralization, which is concretized by the capture, the cell phone jammer or the destruction of the aircraft.
Merging the means for almost perfect detection
“There is no panacea in this area, warns the manager.Each situation requires appropriate responses depending on the location (city, countryside, nuclear power plant, airport, prison …), financial means, technical background and available human forces “. For the detection phase, an active radar is generally used – it emits an electromagnetic wave whose listening makes it possible to locate any object moving in a given radius.
Passive radar can be used to track all the surrounding waves for microchange. Similarly, acoustic tracking systems can be deployed, but they are inefficient in a noisy environment like cities. Finally, laser radars (Lidar) or the technique of direction-finding, which focuses on the exchanges between the operator and his aircraft, also help to detect flying vehicles.
On a site to protect, once the threat is proven, the identification will be performed by a human operator or an automatic turret that will use high resolution cameras and / or infrared. “Artificial intelligence algorithms for pattern recognition can be very useful, for example, by distinguishing a bird from a drone, so as not to trigger the alarm for nothing,” says Onera’s expert. The ideal is obviously to adapt and combine all these technologies. “Today, by merging the radar data and radio direction-finding surveys, we have almost no false alarms,” confirms Michel Dechanet, the “Mr. Drones” of Thales Air Systems.
The European electronics group, specialized in defense systems, is involved in the Hologarde project (in partnership with Aéroports de Paris) to develop ultra-powerful radars. “They detect objects of about 10 centimeters at a maximum distance of 5 kilometers, says the engineer.By next year, we hope to extend our field to 10 kilometers.” A project “closely monitored” by the army, says the Air Force General Jean-Christophe Zimmermann, adding that the French forces have already chosen, as part of the program “Intermediate means of struggle against drugs”, a semi-automatic system. automated combining radar and optronics.