Publications related to A Low-Loss Planar Ka-Band Antenna Subarray for Space Applications

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

Magnetism of Single Surface Adsorbed Atoms Studied with Radio-Frequency STM

Clément Marie Soulard

This thesis investigates the magnetic properties of single atoms and molecules adsorbed on thin magnesium oxide decoupling layers, grown on a silver single crystal. To address these systems experimentally, we use a low temperature scanning tunneling micros ...

EPFL2024

Modeling and optimization of PCB coils for inductive power transfer systems

Xiaotong Du

The auxiliary power supply for medium voltage converters requires high insulation capability between the source and the load. Inductive power transfer technology, with an air gap between the primary and secondary coil, offers such high insulation capabilit ...

EPFL2024

Biomaterial devices on Arecanut palm leaf for microwave applications

Anja Skrivervik, Sujith Raman

This paper presents an investigation on the possibility of arecanut palm leaf as a biomaterial substrate for various microwave devices such as transmission lines, antenna, filter and a radio frequency identification device (RFID). The dielectric properties ...

IEEE2023

High power mm-wave loss measurements of ITER ex-vessel waveguide components at the FALCON test facility at the Swiss Plasma Center

René Chavan, Timothy Goodman, Avelino Mas Sanchez, Anastasia Xydou, Humberto Torreblanca Quiroz

Many future fusion devices will rely heavily, if not solely, on electron cyclotron (EC) heating subsystems to provide bulk heating, instability control (neoclassical tearing mode (NTM) stabilization), and thermal instability control. Efficient use of the i ...

E D P SCIENCES2023

Microstrip patch antennas with broad beamwidth

Ismael Vico Triviño

Microstrip antennas offer a broad set of advantages such as low profile, light weight, easy fabrication and low cost. As these are desirable or even critical for a broad range of applications, there has been a large interest for these antennas in the anten ...

EPFL2023

Time-Domain Integration of Broadband Terahertz Pulses via Tapered Two-Wire Waveguide

Alessandro Tomasino

In this work, we report on the implementation of a time-domain integrator device operating on arbitrary broadband Terahertz (THz) pulses. This analog signal-processing functionality is implemented by employing a two-wire waveguide (TWWG) variant, based on ...

IEEE2023

Scattering from Time-Modulated Transmission-Line Loads: Theory and Experiments in Acoustics

Romain Christophe Rémy Fleury, Matthieu Francis Malléjac

Scattering wave systems that are periodically modulated in time offer many new degrees of freedom to control waves in both the spatial and frequency domains. Such systems, albeit linear, do not conserve frequency and require the adaptation of the usual the ...

American Physical Society (APS)2023

Q-Factor Bounds for Microstrip Patch Antennas

Anja Skrivervik

Antenna bounds are a useful tool in assessing the feasibility or performance of an antenna design. Microstrip patch antennas are often limited by their relatively narrow bandwidth, and therefore Q-factor is an important design parameter, as it is related t ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Waveguide amplifier and waveguide amplifier fabrication method

Tobias Kippenberg, Xinru Ji, Yang Liu, Zheru Qiu

The present invention concerns a waveguide amplifier comprising: - at least one embedding cladding material or layer, and - at least one rare-earth ion implanted silicon nitride material or layer embedded in the at least one embedding cladding material or ...

2023

Nanomechanical resonators with low dissipation for quantum optomechanics

Alberto Beccari

Fields of technology as diverse as microwave filter construction, characterization of material interfaces with atomic precision, and detection of gravitational waves from astronomical sources employ mechanical resonators at their core. The utility of mecha ...

EPFL2023

Impact of Hysteresis Losses in Hybrid (HTS-LTS) Coils for Fusion Applications

Davide Uglietti

Several conductor designs featuring High Temperature Superconducting (HTS) stacked tapes for fusion coils are being proposed. These conductors are planned to operate in time-varying magnetic field and current; thus, the estimation of AC losses is fundament ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Subthreshold VO2 vertical switches for large-bandwidth millimeter-wave and sub-terahertz detection

Mihai Adrian Ionescu, Fatemeh Qaderi Rahaqi, Daesung Park, Ali Gilani

n-linear impedance characteristics of VO2 offer solutions to highly sensitive radio-frequency (RF), millimeterwave (mm-wave), and terahertz (THz) detectors. We demonstrate high-speed broadband sensibility of miniaturized VO2 switches by utilizing the nonli ...

IEEE2022

4-Port Microstrip planar resonator for multiband microwave material characterization applications

Anja Skrivervik, Sujith Raman

Planar microstrip resonators suitable for material characterization application are presented in this paper. The prototype consists of three resonators fed through four ports in a planar dielectric substrate without any additional resonators. The resonator ...

IEEE2022

Reduced basis methods for numerical room acoustic simulations with parametrized boundaries

Jan Sickmann Hesthaven, Hermes Sampedro Llopis

The use of model-based numerical simulations of wave propagation in rooms for engineering applications requires that acoustic conditions for multiple parameters are evaluated iteratively, which is computationally expensive. We present a reduced basis metho ...

ACOUSTICAL SOC AMER AMER INST PHYSICS2022

Interaction of lightning-generated electromagnetic fields with overhead and underground cables

Farhad Rachidi-Haeri, Marcos Rubinstein, Carlo Alberto Nucci

In this chapter, we discussed the TL theory and its application to the problem of lightning electromagnetic field coupling to transmission lines. After a short discussion on the underlying assumptions of the TL theory, we described seemingly different but ...

IET2022

Ultra-Small Bent Meta-Waveguide Filters

Maliheh Khatibi Moghaddam, Romain Christophe Rémy Fleury

This paper demonstrates the capability of locally resonant metamaterials (LRMs) for creating compact metallic waveguide E- and H-bends, which are simultaneously working as bandpass filters. For creating these bent meta-filters, we use composite pin-pipe wa ...

IEEE2022

Study of Thin Film LiNbO3 Laterally Excited Bulk Acoustic Resonators

Victor Plessky, Luis Guillermo Villanueva Torrijo, Hüseyin Baris Atakan, Soumya Yandrapalli

This work presents an in-depth study of simulation and measurement results of laterally excited shear bulk acoustic resonators (XBAR) in Lithium Niobate, at 5 GHz with high electromechanical coupling factor (k(t)(2)) as high as 25%, and with impedances at ...

Institute of Electrical and Electronics Engineers2022

RMSSD Is More Sensitive to Artifacts Than Frequency-Domain Parameters: Implication in Athletes? Monitoring

Jean-Marc Vesin, Grégoire Millet, Sasan Yazdani

Easy-to-use and accurate heart rate variability (HRV) assessments are essential in athletes??? follow-up, but artifacts may lead to erroneous analysis. Artifact detection and correction are the purpose of extensive literature and implemented in dedicated a ...

JOURNAL SPORTS SCIENCE & MEDICINE2022

Development of Thin Film Lithium Niobate Shear Bulk Acoustic Wave Resonators

Soumya Yandrapalli

RF MEMS piezoelectric acoustic resonators are the essential building blocks for RF filters used in RF front-end modules for wireless mobile communication due to their compact size in the MHz-GHz frequency range, high Quality factors and large relative band ...

EPFL2022