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Concept

Chirp

Publications associées (10)

An Asymmetric Perturbation Signal for Enhanced Perturbation Injection Capabilities of a Grid-Connected Converter

Drazen Dujic, Andrea Cervone, Jules Christian Georges Macé

Impedance estimation is an important tool for grid- converter interaction evaluation. Using existing grid-connected converters for perturbation injection enables grid impedance estimation during operation without additional hardware (namely dedicated pertu ...

2024

Vibration monitoring based on optical sensing of mechanical nonlinearities in glass suspended waveguides

Yves Bellouard, Tao Yang, Pieter Vlugter, Enrico Casamenti

Vibration monitoring plays a key role in numerous applications, including machinerypredictive maintenance, shock detection, space applications, packaging-integrity monitoring andmining. Here, we investigate mechanical nonlinearities inherently present in s ...

2021

Massively parallel coherent laser ranging using a soliton microcomb

Tobias Kippenberg, Junqiu Liu, Maxim Karpov, Johann Emmeram Riemensberger, 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

Multi-mJ infrared femtosecond hydrogen Raman laser

Christoph Peter Hauri

High-energy pulses at 1.28 mu m are demonstrated by stimulated Raman scattering in hydrogen using two chirped pulses of a Ti: Sapphire laser. The Stokes pulse carrying record-high energy of 4.4 mJ is recompressed to 80 fs. ...

Ieee2016

High-energy femtosecond hydrogen Raman laser

Christoph Peter Hauri

High-energy pulses at 1.28 mu m are demonstrated by stimulated Raman scattering using two chirped pulses of a Ti:Sapphire laser in hydrogen. The Stokes pulse carrying record-high energy of 4.4 mJ is recompressed to 80 fs. ...

Ieee2016

Dynamic nuclear polarization by frequency modulation of a tunable gyrotron of 260 GHz

Stefano Alberti, Jean-Philippe Ansermet, Falk Hans Braunmüller, Murari Soundararajan, Philippe Cuanillon, Dongyoung Yoon

An increase in Dynamic Nuclear Polarization (DNP) signal intensity is obtained with a tunable gyrotronproducing frequency modulation around 260 GHz at power levels less than 1W. The sweep rate of frequency modulation can reach 14 kHz, and its amplitude is ...

Academic Press2016

Differential chirped-pulse pair for sub-meter spatial resolution Brillouin distributed fiber sensing

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang

A distributed fiber sensor based on a differential chirped-pulse pair Brillouin optical time domain analysis (DCPBOTDA) is proposed for sub-meter spatial resolution sensing. The technique is based on the subtraction of two measurements made with the same p ...

SPIE2015

The varying w spread spectrum effect for radio interferometric imaging

Yves Wiaux, Rafael Eduardo Carrillo Rangel, Jason Douglas McEwen

We study the impact of the spread spectrum effect in radio interferometry on the quality of image reconstruction. This spread spectrum effect will be induced by the wide ﬁeld-of-view of forthcoming radio interferometric telescopes. The resulting chirp modu ...

2013

Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques

Pierre Vandergheynst, Yves Wiaux, Rémi Gribonval, Gilles Puy

We advocate a compressed sensing strategy that consists of multiplying the signal of interest by a wide bandwidth modulation before projection onto randomly selected vectors of an orthonormal basis. Firstly, in a digital setting with random modulation, con ...

Institute of Electrical and Electronics Engineers2012

Narrow-band multiresonant plasmon nanostructure for the coherent control of light: An optical analog of the xylophone

Olivier Martin

We demonstrate that it is possible to combine several small metallic particles in a very compact geometry without loss of their individual modal properties by adding a gold metallic film underneath. This film essentially acts as a "ground plane" which chan ...

2008