Publications related to Frequency-hopping spread spectrum

Validation of short-pulse reflectometry turbulence measurements with a synthetic diagnostic

Stefano Coda, Stephan Brunner, Oleg Krutkin, Umesh Kumar, Mackenzie Peter-Fulford Van Rossem, Samuele Mazzi

Experimental measurements of the turbulence amplitude utilizing a short pulse reflectometry method are presented. Two discharges with shaped plasma possessing opposite signs of triangularity are considered and a higher turbulence amplitude is found in the ...

IOP Publishing Ltd2024

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

Chaotic microcomb-based parallel ranging

Tobias Kippenberg, Aleksandr Tusnin, Junqiu Liu, Anton Lukashchuk

The intrinsic random amplitude and phase modulation of 40 distinct lines of a microresonator frequency comb operated in the modulation instability regime are used to realize massively parallel random-modulation continuous-wave light detection and ranging, ...

Nature Publishing Group2023

Intelligent RF System for Ultra Low Power Spectrum Sensing with Machine Learning

Naci Pekçokgüler

The crowdedness of the RF spectrum constitutes problems in communication, however it also accommodates large amount of useful information. This information can be used to determine existing signals and operating contexts. However, spectrum condition varies ...

EPFL2024

Topological MIMO Optical Signal Processing

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

An important advantage of optical signal processing is the possibility of performing various operations in parallel. Among the techniques proposed for parallel optical signal processing, frequency division multiplexing (FDM) is a well-known approach, in wh ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Electronic metadevices for terahertz applications

Elison de Nazareth Matioli, Mohammad Samizadeh Nikooytabalvandani

The evolution of electronics has largely relied on downscaling to meet the continuous needs for faster and highly integrated devices(1). As the channel length is reduced, however, classic electronic devices face fundamental issues that hinder exploiting ma ...

NATURE PORTFOLIO2023

A KL Divergence-Based Loss for In Vivo Ultrafast Ultrasound Image Enhancement with Deep Learning

Jean-Philippe Thiran, Roser Vinals Terres

Ultrafast ultrasound imaging, characterized by high frame rates, generates low-quality images. Convolutional neural networks (CNNs) have demonstrated great potential to enhance image quality without compromising the frame rate. However, CNNs have been most ...

2023

Development of algorithms for the end-end system simulation and performance analysis for a high-frequency magnetic diagnostic system: Application to ITER, JET and TCV

Duccio Testa

An innovative and very detailed end-to-end system modelling tool has been developed and applied to test on simulated data the actual measurement capabilities of any generic high frequency (HF) magnetic diagnostic systems. The main goal of this rather compl ...

2022

Cellular Fronthauling for Data Capacity Increase in Underserved Spaces

Adrian Schumacher

The increase in wireless data traffic continues and is a product of several factors. First, new technologies and capabilities enable new use cases for which new products emerge. Then, with the growing user adoption over time, the data traffic is further in ...

EPFL2022

Enhanced radio-frequency performance of niobium films on copper substrates deposited by high power impulse magnetron sputtering

Fabio Avino

We present a study of radio frequency properties of niobium films deposited on copper by two different approaches based on High Power Impulse Magnetron Sputtering, namely with a DC voltage biased substrate and with bipolar target voltage. Such approaches e ...

2022

A technique for non-intrusive greedy piecewise-rational model reduction of frequency response problems over wide frequency bands

Fabio Nobile, Davide Pradovera

In the field of model order reduction for frequency response problems, the minimal rational interpolation (MRI) method has been shown to be quite effective. However, in some cases, numerical instabilities may arise when applying MRI to build a surrogate mo ...

2022

Minkowski's Loop Fractal Antenna Dedicated to Sixth Generation (6G) Communication

Maria-Alexandra Paun

In this study, we will discuss the engineering construction of a special sixth generation (6G) antenna, based on the fractal called Minkowski's loop. The antenna has the shape of this known fractal, set at four iterations, to obtain maximum performance. Th ...

MDPI2022

New Technologies to Enhance the Figures-of-Merit of GaN Power Devices

Luca Nela

Gallium Nitride (GaN) has enabled groundbreaking developments in the field of optoelectronics and radio frequency communication. More recently, GaN devices for power conversion applications have demonstrated excellent potential. Thanks to Gallium Nitride w ...

EPFL2022

Directional Cross-Correlation for Improved Aberration Phase Estimation in Pulse-Echo Speed-of-Sound Imaging

Jean-Philippe Thiran, Samuel Denys Beuret, Simon Canales

There has been a recent surge in methods targeting the recovery of a speed-of-sound map from pulse-echo ultrasound measurements. We focused in this work on a particular technique and identified a drawback shared by similar methods - namely the necessity of ...

IEEE2021

Optical frequency comb based parallel fm lidar

Tobias Kippenberg, Anton Lukashchuk

In a LIDAR device (100) a laser light source (110) generates first laser light having a first laser frequency which is frequency modulated with a first frequency modulation. A non-linear optical element (120) receives the first laser light and generates th ...

2021

The effect of low-frequency equalisation on preference and sensorimotor synchronisation in music

Steffen Alexander Herff

Equalisation, a signal processing technique commonly used to shape the sound of music, is defined as the adjustment of the energy in specific frequency components of a signal. In this work, we investigate the effects of equalisation on preference and senso ...

SAGE PUBLICATIONS LTD2021

Frequency Division Using a Soliton-Injected Semiconductor Gain-Switched Frequency Comb

Tobias Kippenberg, Junqiu Liu, Wenle Weng

By injecting a soliton microcomb into a semiconductor laser that is driven by a sinusoidal current at the subharmonic frequencies of the soliton rate, we demonstrate broadband gain-switched frequency comb generation and low-noise microwave synthesis. (C) 2 ...

IEEE2020

A Vibrational Technique for in vitro Intraoperative Prosthesis Fixation Monitoring

Kamiar Aminian, Hooman Dejnabadi, Seyed Abdolmajid Yousefsani

Objective: In this paper, a new vibrational modal analysis technique was developed for intraoperative cementless prosthesis fixation evaluation upon hammering. Methods: An artificial bone (Sawbones)-prosthesis system was excited by sweeping of a sine signa ...

2020

Massively parallel coherent laser ranging using a soliton microcomb

Tobias Kippenberg, Junqiu Liu, Maxim Karpov, Erwan Guillaume Albert Lucas, Wenle Weng, Anton Lukashchuk

Coherent ranging, also known as frequency-modulated continuous-wave (FMCW) laser-based light detection and ranging (lidar)(1) is used for long-range three-dimensional distance and velocimetry in autonomous driving(2,3). FMCW lidar maps distance to frequenc ...

NATURE PUBLISHING GROUP2020

Physical Layer Aspects of LoRa and Full-Duplex Wireless Transceivers

Orion Afisiadis

Wireless communications are currently faced with two main challenges. The first challenge stems from the enormous number of Internet of Things (IoT) devices that transmit very small amounts of data. The second challenge is the need for ever-increasing data ...

EPFL2020