Publications related to Design Concerns for In-body Antennas Based on Frequency Analysis of Fundamental Radiation Limitations

Enabling Wide Bandwidth in Substrate-Integrated Waveguide Slot Antennas by Using Low-Index Metamaterials

Romain Christophe Rémy Fleury, Jalaledin Tayebpour, Amir Jafargholi

This paper presents a solution to overcome the inherently limited bandwidth of substrate-integrated waveguide (SIW) slot antennas. It is analytically shown that by decreasing the permittivity of a dielectric loaded slot antenna, the resulting bandwidth inc ...

American Physical Society (APS)2024

Hints of the Photonic Nature of the Electromagnetic Fields in Classical Electrodynamics

Farhad Rachidi-Haeri, Marcos Rubinstein

Several recent publications show that the electromagnetic radiation generated by transmitting antennas satisfy the following universal conditions: The time domain radiation fields satisfy the condition A ≥ h/4π ⇒ q ≥ e where A is the action of the radiatio ...

2023

Analytic Approximation of In-Body Path Loss for Implanted Antennas

Anja Skrivervik, Mingxiang Gao, Zvonimir Sipus

Implantable bioelectronic devices predominantly use wireless links for communication and/or power transfer. When considering transmitting implanted antennas, electromagnetic radiation through biological media is highly attenuated, and previous work has sho ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Radiation Patterns of RF Wireless Devices Implanted in Small Animals: Unexpected Deformations Due to Body Resonance

Anja Skrivervik, Stéphanie Lacour, James Daniel Rosenthal, Mingxiang Gao, Kangling Wu, Zvonimir Sipus, German Augusto Ramirez Arroyave

One challenge in designing RF wireless bioelectronic devices is the impact of the interaction between electromagnetic waves and host body tissues on far-field wireless performance. In this paper, we investigate a peculiar phenomenon of implantable RF wirel ...

2023

Measuring the electron energy distribution in tokamak plasmas from polarized electron cyclotron radiation

Arsène Stéphane Tema Biwole

In this doctoral thesis, a promising technique has been used for the measurement of non-thermal electrons in TCV. The technique employs a Vertical viewing ECE to more easily discriminate the radiation according to the energy of the electrons. Successful ...

EPFL2023

Topology Optimization of an Electromagnet Manipulator for 3D Uniform Magnetic Field Generation

Yves Perriard, Adrien Jean-Michel Thabuis, Xiaotao Ren, Maribel Caceres Rivera

Magnetic manipulation is a method used for biomedical applications to remotely control micro-robots in a contactless manner. The electromagnet manipulator should control a magnetic field with 3 degrees of freedom inside a region of interest. In various cas ...

Institute of Electrical and Electronics Engineers2023

Metamaterial graphene photodetector with bandwidth exceeding 500 gigahertz

Michael Baumann, Yesim Koyaz

Although graphene has met many of its initially predicted optoelectronic, thermal, and mechanical properties, photodetectors with large spectral bandwidths and extremely high frequency responses remain outstanding. In this work, we demonstrate a >500 gigah ...

American Association for the Advancement of Science2023

Effect of mechanical nonlinearity on the electromagnetic response of a microwave tunable metamaterial

Taha Goudarzi, Romain Christophe Rémy Fleury, Bakhtiyar Orazbayev, Rayehe Karimi Mahabadi

Tunable metamaterials functionalities change in response to external stimuli. Mechanical deformation is known to be an efficient approach to tune the electromagnetic response of a deformable metamaterial. However, in the case of large mechanical deformatio ...

IOP Publishing Ltd2022

Design of a low-loss hybrid silicon-organic terahertz field detector

Ileana-Cristina Benea-Chelmus, Francesco Bertot, Alessandro Tomasino

We propose an innovative design for an integrated, low-loss on-chip terahertz (THz) field detector based on hybrid silicon-organic slot waveguides and THz antennas. We perform a numerical study of the dependency of electro-optic interaction on geometrical ...

IEEE2022

On the reconstruction of the attenuation function of a return-stroke current from the Fourier Transform of finite-duration measurements

Farhad Rachidi-Haeri, Marcos Rubinstein

A correct representation of the lightning current is crucial when the electromagnetic field radiated to a point of interest has to be computed. Based on the engineering models of Transmission Line type, such representation involves the knowledge of the ret ...

2022

Spectral analysis for transmission eigenvalue problems with and without the complementing conditions

Jean Louis-Alexandre Fornerod

The interior transmission eigenvalue problem is a system of partial differential equations equipped with Cauchy data on the boundary: the transmission conditions. This problem appears in the inverse scattering theory for inhomogeneous media when, for some ...

EPFL2022

Controlling the magnetic and electric responses of dielectric nanoparticles via near-field coupling

Olivier Martin, Andrei Kiselev

Among the two materials families used in nanophotonics, the fundamental mode for metal nanostructures is electric, while that for dielectric nanostructures is magnetic. Consequently, the optical properties of hybrid dimers that incorporate both materials h ...

2022

Electromagnetic waves under nonstationary conditions, the connection with parity-time symmetry and studies on resonant systems

Theodoros Koutserimpas

In this thesis, the electromagnetic wave propagation is studied in nonstationary-medium scenarios. The electromagnetic fields under material time-modulation are shown to conserve their momentum but not their energy. The mathematical foundations and analysi ...

EPFL2021

Time-Varying Components for Enhancing Wireless Transfer of Power and Information

Romain Christophe Rémy Fleury, Mohammad Sajjad Mirmoosa, Xuchen Wang

Temporal modulation of components of electromagnetic systems provides an exceptional opportunity to engineer the response of those systems in a desired fashion, both in the time and frequency domains. For engineering time-modulated systems, one needs to th ...

American Physical Society (APS)2021

Structured light generation by refractive-diffractive micro optical array illuminators

Maryam Yousefi

Structured light generation having broad applications in different optical fields, is the topic of this thesis. Our structured light generation strategy is based on applying periodic microoptical elements at the refraction-diffraction limit, under a focuse ...

EPFL2021

Microwave or millimeter wave passive components or devices

Maliheh Khatibi Moghaddam, Romain Christophe Rémy Fleury

A passive device comprising a hollow waveguide including first and second wall structures extending in a guiding direction, an interconnecting base extending between the wall structures and an enclosure extending between the wall structures, the enclosure ...

2021

Sommerfeld Integrals and Their Relation to the Development of Planar Microwave Devices

Krzysztof Michalski, Juan Ramon Mosig

This paper deals with the mathematical expressions called Sommerfeld integrals. Introduced by A. Sommerfeld in 1909, they are mathematically equivalent to inverse Hankel transforms. The original historical goal of these integrals was to provide an accurate ...

Ieee-Inst Electrical Electronics Engineers Inc2021

Instantaneous radiation from time-varying electric and magnetic dipoles

Romain Christophe Rémy Fleury, Mohammad Sajjad Mirmoosa

Radiation from magnetic and electric dipole moments is a key subject in the theory of electrodynamics. Although people treat the problem thoroughly in the context of the frequency domain, the problem is still not well understood in the context of the time ...

2020

Locating Transient Directional Sources in Free Space Based on the Electromagnetic Time Reversal Technique

Farhad Rachidi-Haeri, Marcos Rubinstein, Qi Li

Traditional location methods such as time of arrival and direction of arrival have been widely used to locate transient radiation sources. However, these approaches neglect the directional radiation pattern of the sources. Locating directional sources is a ...

2020

Zero Index Metamaterial for High Gain Array

Tingyong Jiang

Many metamaterials, including metal wire grid, was invented to enhance the performance of the antenna in the last decade. A novel zero index metamaterial (ZIM), consisting of double metal layers with periodic circular perforation cells, was proposed and st ...

IEEE2020