Scalable Multi‐Target Illusion via a Segmented Spatiotemporal Metasurface

Abstract

ABSTRACT A kaleidoscope converts a few physical fragments into numerous images through repeated mirror reflections, yielding visual scene richer than the objects themselves. This optical phenomenon shows that a perceived scene can be reconstructed by beam redirection and spatial reorganization. Inspired by this principle, we propose a scalable multi‐target illusion based on a segmented spatiotemporal metasurface . It acts as an electromagnetic kaleidoscope and operates through the proposed parallel‐sequence spectral translation mechanism (PSTM): one physical aperture is partitioned into independently driven segments, each loaded with a distinct time‐varying bias sequence. Under linear frequency‐modulated signal illumination, PSTM translates the echo spectrum into multiple independently coded frequency‐shifted components. After signal processing by the detector, these sequence‐translated spectral components are reconstructed as scalable false targets in the range–velocity plane. Moreover, the reflection amplitudes of individual targets can be further tuned by aperture allocation. A programmable metasurface is designed and fabricated to validate the concept. Experiments demonstrate the generation of two, three, four, and five false targets, with the measured range–velocity features closely matching theoretical predictions. This work extends metasurface‐based illusion from single‐response modulation to scalable multi‐target scene reconstruction with controllable multidimensional features, providing a flexible framework for electromagnetic illusion generation from a single physical aperture.