Publications associées à Optical Sinc-shaped Nyquist Pulses from Rectangular Frequency Comb Synthesis for High Spectral Efficiency

Impact of beam-coupling impedance on the Schottky spectrum of bunched beam

Tatiana Pieloni, Nicolas Frank Mounet, Christophe Emmanuel R. Lannoy

The Schottky monitors of the Large Hadron Collider (LHC) can be used for non-invasive beam diagnostics to estimate various bunch characteristics, such as tune, chromaticity, bunch profile or synchrotron frequency distribution. However, collective effects, ...

Iop Publishing Ltd2024

LHC Schottky Spectrum from Macro-Particle Simulations

Tatiana Pieloni, Nicolas Frank Mounet, Christophe Emmanuel R. Lannoy

We introduce a method for building Schottky spectra from macro-particle simulations performed with the PyHEADTAIL code, applied to LHC beam conditions. In this case, the use of a standard Fast Fourier Transform (FFT) algorithm to recover the spectral conte ...

JACoW Publishing2022

Localization errors of the stochastic heat equation

David Jean-Michel Candil

In this thesis, we study the stochastic heat equation (SHE) on bounded domains and on the whole Euclidean space

\R^d.

We confirm the intuition that as the bounded domain increases to the whole space, both solutions become arbitrarily close to one another ...

EPFL2022

Versatile shaping of optical frequency combs and applications

Jianqi Hu

Optical frequency combs are a series of phase-locked and equidistant laser lines in the spectral domain. In the time domain, they correspond to periodic pulse trains by the Fourier relation. The ability to shape optical combs and pulse trains is pivotal to ...

EPFL2021

Low-Power and Wide-Tuning Range Frequency Generation for FMCW Radars in Advanced CMOS Technologies

Francesco Chicco

Nowadays, the internet of things (IoT) nodes have started to spread in various domains of our society, from the industrial to the domestic environment. The remote sensing is one among their fundamental functions. The implementation of a radio detection and ...

EPFL2021

Low Noise Clock Generation: Modeling, Analysis and Implementation

Duygu Kostak

The aim of this thesis is to implement, analyze and improve the selected low noise clock generation and distribution techniques for ADC implementations. The thesis is divided into two parts. The first part focuses on the sampling phase generation and distr ...

EPFL2021

Thermal CFTs in momentum space

Andrea Manenti

We study some aspects of conformal field theories at finite temperature in momentum space. We provide a formula for the Fourier transform of a thermal conformal block and study its analytic properties. In particular we show that the Fourier transform vanis ...

Springer Nature2020

Discrete Time Analysis of Phase Detector Timing Nonidealities in Type-I Sub-Sampling PLL

Yusuf Leblebici, Duygu Kostak

The analysis of the effect of sub-sampling phase detector (SSPD) timing nonidealities on Type-I sub-sampling phase-locked loop (SSPLL) is presented. The nonidealities considered are the delay between the complementary sampling clocks and the propagation de ...

IEEE2020

Slepian Guided Filtering of Graph Signals

Dimitri Nestor Alice Van De Ville, Miljan Petrovic

Joint localization of graph signals in vertex and spectral domain is achieved in Slepian vectors calculated by either maximizing energy concentration (mu) or minimizing modified embedded distance (xi) in the subgraph of interest. On the other hand, graph L ...

SPIE-INT SOC OPTICAL ENGINEERING2019

Graph-based Transform Coding with Application to Image Compression

Pascal Frossard, Ntorina Thanou, Giulia Fracastoro

In this paper, we propose a new graph-based coding framework and illustrate its application to image compression. Our approach relies on the careful design of a graph that optimizes the overall rate-distortion performance through an effective graph-based t ...

2019

Reduced Leakage Synchrophasor Estimation: Hilbert Transform Plus Interpolated DFT

Mario Paolone, Asja Derviskadic, Guglielmo Frigo

Synchrophasor estimation is typically performed by means of spectral analysis based on the discrete Fourier transform (DFT). Traditional DFT approaches, though, suffer from several uncertainty contributions due to the stationarity assumption, spectral leak ...

2018

Sampling the Multiple Facets of Light

Gilles Baechler

The theme of this thesis revolves around three important manifestations of light, namely its corpuscular, wave and electromagnetic nature. Our goal is to exploit these principles to analyze, design and build imaging modalities by developing new signal proc ...

EPFL2018

Towards Generalized FRI Sampling with an Application to Source Resolution in Radioastronomy

Martin Vetterli, Thierry Blu, Hanjie Pan

It is a classic problem to estimate continuous-time sparse signals, like point sources in a direction-of-arrival problem, or pulses in a time-of-flight measurement. The earliest occurrence is the estimation of sinusoids in time series using Prony's method. ...

Institute of Electrical and Electronics Engineers2017

FRIDA: FRI-Based DOA Estimation For Arbitrary Array Layouts

Martin Vetterli, Robin Scheibler, Hanjie Pan, Ivan Dokmanic, Eric Bezzam

In this paper we present FRIDA—an algorithm for estimating directions of arrival of multiple wideband sound sources. FRIDA combines multi-band information coherently and achieves state- of-the-art resolution at extremely low signal-to-noise ratios. It work ...

IEEE2017

Modeling Creeping Flow through a Closed Crack with a Self-Affine Geometry and an Extension to Permeability of Cracked Media, Poromechanics VI

Jean-François Molinari, Guillaume Anciaux, Vladislav Yastrebov

To model a creeping flow through closed cracks in cracked materials we study a normal mechanical contact between two elastic half-spaces with rough surfaces is studied. The roughness is modeled using a filtering technique in Fourier space: the root mean sq ...

2017

A Spectral Method for Generating Surrogate Graph Signals

Dimitri Nestor Alice Van De Ville, Elvira Pirondini, Anna Vybornova, Martina Coscia

The increasing availability of network data is leading to a growing interest in processing of signals on graphs. One notable tool for extending conventional signal-processing operations to networks is the graph Fourier transform that can be obtained as the ...

IEEE Institute of Electrical and Electronics Engineers2016

Global Optimization for Image Restoration in Optical/IR Interferometry

Ferréol Arnaud Marie Soulez

Many image reconstruction algorithms have been proposed to cope with optical/IR interferometric data. A first difficulty is to deal with the sparsity of the data and the uneven u-v coverage. This is usually overcome by imposing a priori constraints to the ...

SPIE2016

Vertex-Frequency Analysis on Graphs

Pierre Vandergheynst, David Shuman, Benjamin Ricaud

One of the key challenges in the area of signal processing on graphs is to design dictionaries and transform methods to identify and exploit structure in signals on weighted graphs. To do so, we need to account for the intrinsic geometric structure of the ...

Academic Press Inc Elsevier Science2016

Ultra-Low Power Estimation of Heart Rate Under Physical Activity Using a Wearable Photoplethysmographic System

David Atienza Alonso, Srinivasan Murali, Francisco Javier Rincon Vallejos, Elisabetta De Giovanni

In the last years, the need for enhancing health and preventing problems with remote monitoring is increasing. A non-invasive low-cost technique for processing bio-signals and monitoring vital parameters, at rest and during physical activity, is the use of ...

IEEE Press2016

Superresolution Reconstruction for Magnetic Resonance Spectroscopic Imaging Exploiting Low-Rank Spatio-Spectral Structure

Jeffrey Adam Kasten

Magnetic resonance spectroscopic imaging (MRSI) is a rapidly developing medical imaging modality, capable of conferring both spatial and spectral information content, and has become a powerful clinical tool. The ability to non-invasively observe spatial ma ...

EPFL2015