A research team working for the Chinese People’s Liberation Army Air Force announced that they had successfully detected an aircraft with a radar cross-section similar to the American F-22 and F-35 fighters, based on electromagnetic waves emitted by SpaceX’s Starlink satellites.
SpaceX, owned by Elon Musk, is known for having the largest network of satellites in low Earth orbit, with more than 6,000 satellites that generate high-frequency signals to deliver high-speed internet.
In their experiments, the team flew small DJI Phantom 4 Pro drones with the same radar cross-section as these two aircraft off the coast of Guangdong Province in southern China, and captured their tracks and even their movement on radar.
Scientists explained that this was possible because the march was illuminated by electromagnetic radiation from a Starlink satellite passing over the Philippines.
According to the study, which the team announced was accepted for publication in the Journal of Signal Processing, their radar did not emit any radiation, but instead acted as a receiver for electromagnetic signals broadcast by communications satellites like Starlink when they fly over airspace, which were deflected by the drone’s presence and indicated its presence.
(Al Jazeera)
The most powerful fighters in the world
At a cost of $350 million, the F-22 is one of the most advanced fighter jets in the world, equipped with fifth-generation technologies, combining high speed, superior maneuverability, extreme stealth, and sensor integration into a single weapon platform, and operating in all weather conditions.
This fighter aircraft is primarily designed for air superiority missions, i.e. operations aimed at controlling the airspace over a given area during a military conflict.
On the other hand, the F-35 stealth aircraft, which costs up to $115.5 million, is a multi-role fighter, also of the fifth generation, capable of conducting air-to-air combat, precision ground strikes, and reconnaissance missions. It can switch between these roles during a single mission, giving it flexibility in a wide range of scenarios.
In contrast, China has the Chengdu J-20 fighter, which costs close to the F-35, and is also a fifth-generation multi-role fighter developed by Chengdu for the People’s Liberation Army Air Force. It is China’s most advanced fighter aircraft.
In general, fifth-generation fighters are equipped with low-observable (stealth) characteristics to reduce the radar cross section. This is done by using advanced chemical paint that does not easily scatter radar waves, building the aircraft with an engineering that exceeds the capabilities of the radar, and hiding weapons inside the aircraft fuselage.
F-35A fighter (Anadolu)
Different dispersion
According to the new study, these electromagnetic waves emitted by the Starlink satellites were scattered by the drones through the phenomenon of “forward scattering,” which allowed them to be detected. Forward scattering refers to the deflection of waves by small angles so that they continue to move in roughly the same direction as they were before the scattering.
Think of it like a heavy bowling ball rolling down a lane full of little pins scattered everywhere. As the ball (which represents a wave) rolls, it occasionally touches or bumps into a pin, causing it to wobble a little, but it keeps rolling in roughly the same direction.
Similarly, when waves such as light or radio waves encounter these fighter jets, they “bump” into them, causing the waves to be slightly deflected, but they continue to move forward.
The researchers explained that the trace of stealth aircraft can always be detected when they pass between satellites high in the atmosphere and their receivers on the ground, and the more satellites there are (which is expected to happen in the future), the easier the aircraft will be to detect.
This research team intends to complete their experiments on real stealth aircraft flying at high altitudes, to confirm the results of their research, because although the radar cross-section of the small drones is similar to that of stealth aircraft, the drones flew at low altitudes.
