Wireless Communications through a Simplified Architecture Based on Time‐Domain Digital Coding Metasurface

Abstract

Tailoring the electromagnetic responses by metasurface greatly expands one's capabilities to manipulate light in a controlled manner. Either amplitude or phase of the incident wave can be altered during the light–matter interaction, and thus opens the possibility of information modulation without conventional analog or digital circuits. A prototype of quadrature phase‐shift keying (QPSK) wireless communication based on time‐domain digital coding metasurface, whose reflection properties can be varied within different time slots by changing the biasing voltages of varactor diodes in specially designed meta‐atoms, is developed here. As the information is transformed into binary bit streams and mapped to pulse sequences of the biasing voltage, the baseband digital signal is directly modulated to the carrier wave through the digital coding metasurface. Compared to the earlier version of binary frequency‐shift keying architecture based on digital coding metasurface, the proposed QPSK system has a much higher data‐transmission rate for wireless communications. A proof‐of‐concept experiment is conducted to prove the real‐time transmission ability of this system, where a video is delivered between the transmitter and receiver with high accuracy and date rate. The presented work is promising in the development of next‐generation wireless communication technologies.

Full Manipulation of the Power Intensity Pattern in a Large Space‐Time Digital Metasurface: From Arbitrary Multibeam Generation to Harmonic Beam Steering Scheme

“…By designing phase-only metaparticles as a physical coding element and by encoding proper time-varying spatial codes, based on the presented formalism, our proposed structure can be implemented in space-time digital metasurface based systems. [31][32][33][34] Finally, at the end of the article, four investi-gations have been conducted to determine the limits of the validity range of the assumptions. The proposed straightforward approach is expected to broaden the applications of digital coding metasurfaces significantly and exposes a new opportunity for various applications such as multiple-target radar systems and Non-Orthogonal-Multiple_Access (NOMA) communication.…”

Deep Learning Designs of Anisotropic Metasurfaces in Ultrawideband Based on Generative Adversarial Networks

“…[10] Using the active devices to control the digital states of meta-atoms electrically, the programmable metasurfaces have led to numerous novel devices and systems, including programmable holograms, [11] microwave imaging, [12,13] and new-architecture wireless communication systems. [14][15][16][17] Traditionally, for a set of given target parameters, the general methods for designing the metasurfaces are mainly based on trial and error with iterative optimizations, [18,19] in which the iterative optimization approaches can be classified into two types: adjoint-based topology [20,21] and genetic algorithm optimization. [22,23] Although such design methods can produce acceptable results, it remains a big challenge to deploy them in large and realistic scenes due to the large numbers of metaatom structures, high computational costs, and time-consuming numerical simulations.…”

Dynamic Metasurface Antennas for Bit-Constrained MIMO-OFDM Receivers

“…Such surfaces consist of a set of microstrips, each embedded with configurable radiating metamaterial elements [17], [18]. Recent years have witnessed a growing interest in the application of metasurfaces as reflecting surfaces for wireless communications [19]- [23]. In such applications, a metasurface is placed in a physical location where it can aid the BS by reflecting and steering the transmitted waveforms.…”