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Related papers: Sparse Doppler Sensing Based on Nested Arrays

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Dynamic and precise measurement of cerebral blood flow velocity is crucial in neuroscience and the diagnosis of cerebrovascular diseases. Traditional color Doppler ultrasound can only measure the velocity component along the ultrasound…

Medical Physics · Physics 2025-04-25 Shaoyuan Yan , Yiming Ding , Guoao Ma , Yapeng Fu , Kailiang Xu , Dean Ta

Stereoscopic spectral imaging is an observing technique that affords rapid acquisition of limited spectral information over an entire image plane simultaneously. Light from a telescope is dispersed into multiple spectral orders, which are…

Astrophysics · Physics 2007-05-23 Craig E. DeForest , Charles C. Kankelborg

Examination of the umbilical artery with Doppler ultrasonography is performed to investigate blood supply to the fetus through the umbilical cord, which is vital for the monitoring of fetal health. Such examination involves several steps…

This paper introduces a method based on a deep neural network (DNN) that is perfectly capable of processing radar data from extremely thinned radar apertures. The proposed DNN processing can provide both aliasing-free radar imaging and…

Signal Processing · Electrical Eng. & Systems 2023-07-12 Christian Schuessler , Marcel Hoffmann , Martin Vossiek

We present a detection scheme for diffusing wave spectroscopy (DWS) based on a two cell geometry that allows efficient ensemble averaging. This is achieved by putting a fast rotating diffuser in the optical path between laser and sample. We…

Soft Condensed Matter · Physics 2009-11-11 P. Zakharov , F. Cardinaux , F. Scheffold

An optical frequency comb generated with an electro-optic phase modulator and a chirped radiofrequency waveform is used to perform saturation and pump-probe spectroscopy on the $D_1$ and $D_2$ transitions of atomic potassium. With a comb…

Atomic Physics · Physics 2016-12-21 David A. Long , Adam J. Fleisher , David F. Plusquellic , Joseph T. Hodges

Ultrafast lasers ($< 500$ fs) have enabled laser-matter interactions at intensities exceeding $10^{18} \rm{Wcm}^{-2}$ with only millijoules of laser energy. However, as pulse durations become shorter, larger spectral bandwidths are…

The dispersion scan (d-scan) technique has emerged as a simple-to-implement characterization method for ultrashort laser pulses. D-scan traces are intuitive to interpret and retrieval algorithms that are both fast and robust have been…

We report a pilot study with a wide-field laser Doppler detection scheme used to perform laser Doppler anemometry and imaging of particle seeded microflow. The optical field carrying the local scatterers (particles) dynamic state, as a…

Optics · Physics 2013-12-24 Michel Gross , Michael Atlan , Jacques Leng

Technological advances in femtosecond laser sources call for the development of increasingly refined characterization tools implying to enrich the existing panel of operable nonlinear interactions. The present paper describes a novel…

Optics · Physics 2021-02-03 P. Béjot , E. Szmygel , A. Dubrouil , F. Billard , B. Lavorel , O. Faucher , E. Hertz

In this paper an approach for decreasing the computational effort required for the spectral simulations of the water waves is introduced. Signals with majority of the components zero, are known as the sparse signals. Like majority of the…

Computational Physics · Physics 2015-12-22 Cihan Bayindir

Speed-of-sound is a biomechanical property for quantitative tissue differentiation, with great potential as a new ultrasound-based image modality. A conventional ultrasound array transducer can be used together with an acoustic mirror, or…

Computer Vision and Pattern Recognition · Computer Science 2018-07-20 Valery Vishnevskiy , Sergio J Sanabria , Orcun Goksel

Ultrashort laser pulses enable attosecond-scale measurements and drive breakthroughs across science and technology, but their routine use hinges on reliable pulse characterization. Frequency-Resolved Optical Gating (FROG) is a leading…

Optics · Physics 2026-04-29 Abhimanyu Borthakur , Jack Eden Hirschman , Sergio Carbajo

This paper presents an adaptive and intelligent sparse model for digital image sampling and recovery. In the proposed sampler, we adaptively determine the number of required samples for retrieving image based on space-frequency-gradient…

Computer Vision and Pattern Recognition · Computer Science 2017-11-27 Ali Taimori , Farokh Marvasti

Spectral imaging is an umbrella term for energy-resolved x-ray imaging in medicine. The technique makes use of the energy dependence of x-ray attenuation to either increase the contrast-to-noise ratio, or to provide quantitative image data…

Medical Physics · Physics 2021-01-05 Erik Fredenberg

Sparse arrays have emerged as a popular alternative to the conventional uniform linear array (ULA) due to the enhanced degrees of freedom (DOF) and superior resolution offered by them. In the passive setting, these advantages are realized…

Signal Processing · Electrical Eng. & Systems 2023-01-05 Pulak Sarangi , Mehmet Can Hucumenoglu , Robin Rajamaki , Piya Pal

We demonstrate experimentally an optical system for under-sampling several bandwidth limited signals with carrier frequencies that are not known apriori that can be located anywhere within a very broad frequency region between 0-18 GHz. The…

Spectral imaging enables the analysis of optical material properties that are invisible to the human eye. Different spectral capturing setups, e.g., based on filter-wheel, push-broom, line-scanning, or mosaic cameras, have been introduced…

Image and Video Processing · Electrical Eng. & Systems 2024-10-01 Eric L. Wisotzky , Jost Triller , Anna Hilsmann , Peter Eisert

By placing a diffractive element in front of an image sensor, we are able to multiplex the spectral and angular information of a scene onto the image sensor. Reconstruction of the angular-spectral distribution is attained by first…

Optics · Physics 2018-02-06 Peng Wang , Rajesh Menon

Spectral Doppler measurements are an important part of the standard echocardiographic examination. These measurements give important insight into myocardial motion and blood flow providing clinicians with parameters for diagnostic decision…

Image and Video Processing · Electrical Eng. & Systems 2019-11-11 Andrew Gilbert , Marit Holden , Line Eikvil , Mariia Rakhmail , Aleksandar Babic , Svein Arne Aase , Eigil Samset , Kristin McLeod