Technology company Thales has developed a radar that detects small drones from flying birds. The radar can be used for protecting airports and important buildings against malicious drones.
The Squire is the mobile radar system of the Hengelo technology company Thales. It is a radar with an extremely low power motion, which can detect trucks up to a distance of 48 km. When a drone enters the detection field of the radar, a small square appears on the screen, which moves with the flight path of the drone. Wim Schuttert of Thales: “It’s so special, whit this radar we are able to detect and differentiate the drone from birds. The birds are namely identified as green dots.”
The innovation is found mainly on the side of the software, Thales did not have to change the hardware; the super sensitive Squire (full: Signal Quiet Universal Intruder Recognition Equipment). “We have boosted the resolution of the observation possibilities from a tenth to a thousandth square meter.” In other words, Thales has plunged deeper into the noise of the radar signal, and knows how to extract meaningful information.
The crux of the Squire is the measurement of frequency shift, in other words the Doppler effect: when an object moves away from the radar, then the reflected signal gets a lower frequency than the originally transmitted signal. When an object is moving towards the radar, then the reflected signal has a higher frequency.
Different frequency spectrum
When tuning the Squire for detecting smaller drones, Thales discovered that birds and drones showed a distinctly different frequency spectrum. “With birds the reflected spectrum at a wing beat broadens a little bit, with a drone this spectrum is much broader. The difference is large enough to differentiate without mistakes. “The difference between a bird and drone is found mainly in the speed of the propellers of the drone circling, which is compared with the wing beat much higher.
Thales feels that this new functionality of the Squire has an interesting scope. “There are already drones spotted at airports, nuclear power plants and around the White House. At those locations you want to make early drone observations and possible countermeasures. Our radar allows these early observations and can also provide live coordinates of the drone to any drone exterminator. ”
The Squire can recognize smaller drones to approximately 4 km away. To secure Schiphol two installations would be needed at the runway in use: one for the airspace of the landing gears and one for the rising. “When they take another airport runway in use, it is sufficient to move both Squire radars, it’s that easy.”
This article is an adaption of the original article on De Ingenieur.