Metasurface-based radar jammers and deceptors implemented through time-varying metasurfaces

In radar countermeasures, the terms jamming and deception are used to indicate the intentional emission of radio frequency signals whose aim is to interfere with the operation of a radar by saturating its receiver with noise or false information. Electronic radar jammers typically consist of an antenna system and a corresponding circuitry, that captures, elaborates, and re-radiates the proper interfering signals. In this contribution, we present a radar jammer implemented through a time-modulated metasurface. Such a metasurface is an electrically thin artificial structure, whose properties are dynamically changed over time to realize an elaboration of the illuminating signal. We demonstrate that such a metasurface is able to jam Doppler radars, implementing sweep jamming and velocity pull-off techniques.