DTU researchers develop thin coatings to change how drones show up on radar

Researchers at the Technical University of Denmark (DTU) are developing coatings and materials that change a drone's radar signature, making its reflections stronger or weaker, in a project with Aarhus University, the Danish Technological Institute and companies including TICRA and Arctic Unmanned.

One track uses physical vapour deposition, in which a surface is bombarded with atoms, to make very thin coatings. Project leader Samel Arslanagic, head of Electromagnetic Systems at DTU, said first tests on simple shapes such as rectangular plates and a cylinder sharply weakened the reflected signals. Next the method has to be adapted to a drone's complex shape, tested in realistic conditions and checked for whether only part of the surface needs coating.

The coatings must be durable, add no weight and suit industrial production, ideally applied early in a drone's manufacture. A second track develops metasurfaces, artificial materials made of tiny repeating elements that steer how electromagnetic energy scatters, which Arslanagic said would probably be cheaper to make and use than the coating method.