Related Experiment Video
Updated: Dec 23, 2025
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
6.6K
Frequency-Domain and Spatial-Domain Reconfigurable Metasurface.
Guang Yao Liu1, Long Li1, Jia Qi Han1
1Key Laboratory of High Speed Circuit Design and EMC of Ministry of Education, School of Electronic Engineering, Xidian University, Xi'an, Shaanxi 710071, China.
ACS Applied Materials & Interfaces
|April 28, 2020
Summary
This study introduces a novel frequency- and spatial-domain reconfigurable metasurface (FSRM) that flexibly controls electromagnetic waves across multiple frequency bands. The FSRM demonstrates reconfigurable polarization conversion and spatial beam manipulation for advanced smart material applications.
Area of Science:
- Electromagnetic Metamaterials
- Applied Electromagnetics
- Materials Science
Background:
- Digital reconfigurable metasurfaces offer flexible electromagnetic wave manipulation.
- Existing metasurfaces often have limited single-domain performance (spatial or frequency).
Purpose of the Study:
- To propose a general frequency- and spatial-domain reconfigurable metasurface (FSRM).
- To achieve multifrequency band reconfigurable functions for electromagnetic waves.
Main Methods:
- Design and theoretical analysis of a novel FSRM.
- Utilizing PIN diodes for switching polarization conversion across frequency bands.
- Implementing 1-bit programmable digital coding for spatial domain modulation.
Main Results:
- Demonstrated frequency-domain polarization conversion (linear to circular).
- Achieved spatial domain functions including 2D beam scanning and vortex beam generation.
- Experimental validation showed good agreement between measured results and theoretical predictions.
Conclusions:
- The proposed FSRM enables simultaneous frequency and spatial domain reconfigurability.
- This technology opens new avenues for designing smart materials with dynamic electromagnetic functionalities.
- The FSRM provides versatile control over electromagnetic wave properties.
Related Concept Videos
01:27State Space Representation
466
The frequency-domain technique, commonly used in analyzing and designing feedback control systems, is effective for linear, time-invariant systems. However, it falls short when dealing with nonlinear, time-varying, and multiple-input multiple-output systems. The time-domain or state-space approach addresses these limitations by utilizing state variables to construct simultaneous, first-order differential equations, known as state equations, for an nth-order system.
Consider an RLC circuit, a...
Consider an RLC circuit, a...
466
01:21Properties of Fourier Transform I
512
The application of Fourier Transform properties in radio broadcasting is multifaceted, enabling significant advancements in the way signals are transmitted and received. Key areas where these properties are utilized include simultaneous multi-channel transmission, audio clip speed adjustments, live broadcast delays for different time zones, audio frequency adjustments, and signal demodulation.
In radio broadcasting, multiple audio signals often need to be transmitted simultaneously. The Fourier...
In radio broadcasting, multiple audio signals often need to be transmitted simultaneously. The Fourier...
512
01:24Properties of Fourier Transform II
617
The Fourier Transform (FT) is an essential mathematical tool in signal processing, transforming a time-domain signal into its frequency-domain representation. This transformation elucidates the relationship between time and frequency domains through several properties, each revealing unique aspects of signal behavior.
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
617
01:20Discrete-Time Fourier Series
581
The Discrete-Time Fourier Series (DTFS) is a fundamental concept in signal processing, serving as the discrete-time counterpart to the continuous-time Fourier series. It allows for the representation and analysis of discrete-time periodic signals in terms of their frequency components. Unlike its continuous counterpart, which utilizes integrals, the calculation of DTFS expansion coefficients involves summations due to the discrete nature of the signal.
For a discrete-time periodic signal x[n]...
For a discrete-time periodic signal x[n]...
581
01:18Aliasing
476
Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
476
01:20Frequency Response of a Circuit
573
Inductive circuits present intriguing challenges in electrical engineering, particularly during the transition from the time domain to the frequency domain. This transformation involves converting inductors into impedances and utilizing phasor representation.
The transfer function is pivotal in characterizing how these circuits react to various frequencies, facilitating a profound understanding of their behavior. An essential parameter is the time constant, signifying the...
The transfer function is pivotal in characterizing how these circuits react to various frequencies, facilitating a profound understanding of their behavior. An essential parameter is the time constant, signifying the...
573