Fig. 3: The first-harmonic beamforming properties realized by the STC metasurface, in which the incident frequency is 4.12 GHz.
From: Simplified radar architecture based on information metasurface

a, b The beam deflection angles of −20° (a) and 30° (b) when the modulation frequency is 200 kHz. c, d The beam deflection angles of 10° (a) and −40° (b) when the modulation frequency is 100 kHz.