Time-Modulated Metasurface for Spoofing Doppler Radar

This paper presents a time-modulated metasurface for on-air mixing for spoofing Doppler radars. The metasurface’s impedance varies as a function of time which results in on-air mixing of the frequency of the incident wave and the modulation frequency of the metasurface generating multiple harmonics. This phenomenon can be used to trick Doppler radars as the reflected wave from the metasurface gets modulated. The design methodology and the measurement results for the metasurface, with a detailed study of the various parameters affecting the frequency mixing and test results with a radar, have been reported.