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Related papers: Space-Time Modulation: Principles and Applications

200 papers

Utilizing scatterers in communication engineering, such as reconfigurable intelligent surfaces (RISs) and backscatter systems, requires physically consistent models for accurate performance prediction. A multiport model, which also accounts…

Signal Processing · Electrical Eng. & Systems 2025-07-18 Aleksandr D. Kuznetsov , Jari Holopainen , Ville Viikari

Spatio-temporally modulated impedance surfaces can be good candidates for generation of radiating waves with arbitrary eigenstates by breaking momentum and energy conservations. Here, we present a theoretical framework based on the…

Applied Physics · Physics 2021-12-16 Amrollah Amini , Homayoon Oraizi

Unraveling real eigenfrequencies in non-Hermitian $\mathcal{PT}$-symmetric Hamiltonians has opened new avenues in quantum physics, photonics, and most recently, phononics. However, the existing literature squarely focuses on exploiting such…

Classical Physics · Physics 2022-10-07 M. Moghaddaszadeh , M. A. Attarzadeh , A. Aref , M. Nouh

We present an effective medium description of time-modulated dielectric media. By taking the averaged fields over one modulation period, the relationship between them is derived, defining therefore the different constitutive parameters. In…

Optics · Physics 2021-01-04 Dani Torrent

The prospect of ultra-massive multiple-input multiple-output (UM-MIMO) technology to combat the distance problem at the Terahertz (THz)-band is considered. It is well-known that the very large available bandwidths at THz frequencies come at…

Signal Processing · Electrical Eng. & Systems 2019-07-16 Hadi Sarieddeen , Mohamed-Slim Alouini , Tareq Y. Al-Naffouri

Realization of non-reciprocal devices, such as isolators and circulators, is of fundamental importance in microwave and photonic communication systems. This can be achieved by breaking time-reversal symmetry in the system or exploiting…

Applied Physics · Physics 2019-05-01 Junfei Li , Chen Shen , Yangbo Xie , Steven A. Cummer

A unified homogenization procedure for split ring metamaterials taking into account time and spatial dispersion is introduced. The procedure is based on two coupled systems of equations. The first one comes from an approximation of the…

Optics · Physics 2014-09-10 J. D. Baena , L. Jelinek , R. Marques , M. Silveirinha

Using the time periodic ABCD parameters, an expression for the dispersion relation of space-time modulated structures is obtained. The relation is valid for general structures even when the spatial granularity is comparable to the operating…

Applied Physics · Physics 2023-07-19 Sameh Y. Elnaggar , Gregory N. Milford

Temporal metamaterials are artificial materials whose electromagnetic properties change over time. In analogy with spatial media and metamaterials, where their properties change smoothly or abruptly over space, temporal metamaterials can…

Optics · Physics 2025-02-06 Davide Ramaccia , Andrea Alu , Alessandro Toscano , Filiberto Bilotti

Here, we present an overview of a first principles homogenization theory of periodic metamaterials. It is shown that in a rather general context it is possible to formally introduce effective parameters that describe the time evolution of…

Optics · Physics 2020-02-18 Sylvain Lannebère , Tiago A. Morgado , Mário G. Silveirinha

The propagation of the transverse electric (TE) and transverse magnetic (TM) waves in an effectively two-dimensional (2D) isotropic medium is described by Bergmann's equation of acoustics. We develop a dynamical formulation of the…

Mathematical Physics · Physics 2026-04-06 Farhang Loran , Ali Mostafazadeh

The finite-difference time-domain (FDTD) method is applied for modelling of wire media as artificial dielectrics. Both frequency dispersion and spatial dispersion effects in wire media are taken into account using the auxiliary differential…

Materials Science · Physics 2009-11-11 Yan Zhao , Pavel Belov , Yang Hao

In this paper, spatial modulation (SM) is introduced to layered division multiplexing (LDM) systems for enlarging the spectral efficiency over broadcasting transmission. Firstly, the SM aided LDM (SM-LDM) system is proposed, in which…

Information Theory · Computer Science 2018-01-16 Yue Sun , Jintao Wang , Changyong Pan , Longzhuang He , Bo Ai

Communication at millimeter wave (mmWave) frequencies is one of the main novelties introduced in the 5th generation (5G) of cellular networks. The opportunities and challenges associated with such high frequencies have stimulated a number…

Networking and Internet Architecture · Computer Science 2020-04-02 Paolo Testolina , Mattia Lecci , Michele Polese , Marco Giordani , Michele Zorzi

"Space-time" (ST) wave packets constitute a broad class of pulsed optical fields that are rigidly transported in linear media without diffraction or dispersion, and are therefore propagation-invariant in absence of optical nonlinearities or…

Multiscale problems are computationally costly to solve by direct simulation because the smallest scales must be represented over a domain determined by the largest scales of the problem. We have developed and analyzed new numerical methods…

Numerical Analysis · Mathematics 2011-11-11 Björn Engquist , Henrik Holst , Olof Runborg

In this work, we theoretically study temporal interfaces between media with strong spatial dispersion and dielectrics. In particular, we consider a temporal discontinuity that transforms a wire medium sample, a metamaterial with resonant…

Spatial light modulator (SLM) controlled transmission of light through opaque media is a relatively new experimental method with wide applications in various fields. While there has been a surge in research into the technique, there has…

Optics · Physics 2015-03-02 Benjamin R. Anderson , Ray Gunawidjaja , Hergen Eilers

Space-time modulation induced non-reciprocity in EM metasurfaces is proposed and numerically demonstrated using rigorous Generalized Sheet Transitions Conditions (GSTCs) under oblique plane-wave incidence. It is phenomenologically shown…

Optics · Physics 2017-04-03 Shulabh Gupta , Scott. A. Stewart , Tom J. Smy

Fundamental concepts in the quasi-one-dimensional geometry of disordered wires and random waveguides in which ideas of scaling and the transmission matrix were first introduced are reviewed. We discuss the use of the transmission matrix to…

Disordered Systems and Neural Networks · Physics 2023-07-19 Zhou Shi , Matthieu Davy , Azriel Z. Genack