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arXiv · 1412.7791

Spatio-TemporalMetasurface for Real-time 2-D Spectrum Analysis

Shulabh Gupta·Christophe Caloz
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Abstract

A spatio-temporal metasurface is proposed to decompose in real time the temporal frequencies of electromagnetic waves into spatial frequencies onto a two-dimensional plane. The metasurface is analyzed and demonstrated using Fourier analysis. The required transmittance function is derived from an equivalent free-space optical system consisting of the cascade combination of a wedge, a diffraction grating and a focusing lens. The metasurface must exhibit both multi-resonance over a broad bandwidth and 1-D grating-type scanning to achieve the specified 2-D frequency scanning in space. Compared to state-of-the art related systems, the proposed metasurface system is more compact as it requires only one dispersive structure, while maintaining the high frequency resolution that characterizes 2-D spatial-temporal mapping systems.

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Shulabh Gupta, Christophe Caloz. 2014-12-25. Spatio-TemporalMetasurface for Real-time 2-D Spectrum Analysis. https://arxiv.org/abs/1412.7791

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