Concept

Chirp

Related publications (28)

Temporal characterization of individual harmonics of an attosecond pulse train by THz streaking

Christoph Peter Hauri, Fernando Ardana Lamas, Ishkhan Gorgisyan

We report on the temporal pulse characteristics of individual harmonics in an attosecond pulse train by means of photoelectron streaking in a strong low-frequency transient. The scheme allows one to retrieve the pulse durations and first-order chirp of ind ...

2016

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

Time-frequency analysis of long fiber Bragg gratings with low reflectivity

Luc Thévenaz, Sang Hoon Chin

A new technique to investigate the spatial distribution of the reflection spectrum along fabricated long weak fiber Bragg gratings (FBG) is experimentally demonstrated, together with its potential applications for distributed fiber sensing and broadband si ...

Optical Society of America2013

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

Development of Ultraviolet Photon Echo Experiments for the Study of Molecular Dynamics in Solution

This thesis work concerns the development and applications of ultrafast optical techniques and in particular photon echo in the UV range (< 300 nm). Development of these techniques in the UV range is important for studying molecular dynamics in solution, s ...

EPFL2011

, , , , ,

We consider images probed through incomplete and noisy Fourier coverages, both in the context of radio interferometry (RI) and of magnetic resonance imaging (MRI). We show that the quality of signal reconstruction can be signiﬁcantly enhanced by the introd ...

IEEE Signal Process. Soc.2010

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

Broadband decoupling in NMR with frequency-modulated 'chirp' pulses

Geoffrey Bodenhausen

In NMR of spins with I = 1/2 in an isotropic phase, it is demonstrated by simulation and expt. that virtually unlimited bandwidths can be decoupled effectively by using chirp pulses with linear frequency modulation for adiabatic inversion combined with pha ...

1995

A method for exciting transverse magnetization in magnetic resonance

Geoffrey Bodenhausen

In a method for exciting transverse magnetization by irradiating a nuclear spin system subjected to a const. magnetic field with a frequency-modulated RF-pulse (chirp-pulse) and with a further frequency-modulated RF-pulse (further chirp-pulse) for refocusi ...

(Spectrospin AG, Switz.).1994

Graph Chatbot

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.