English
Related papers

Related papers: Measuring the Oscillation Frequency Beyond the Dif…

200 papers

Image sensors are the backbone of many imaging technologies of great importance to modern sciences, being particularly relevant in biomedicine. An ideal image sensor should be usable through all the electromagnetic spectrum (large…

Medical Physics · Physics 2022-03-16 Juan Aguirre

The aim of two-dimensional line spectral estimation is to super-resolve the spectral point sources of the signal from time samples. In many associated applications such as radar and sonar, due to cut-off and saturation regions in electronic…

Information Theory · Computer Science 2020-01-08 Iman Valiulahi , Farzan Haddadi , Arash Amini

Removing speckle noise from medical ultrasound images while preserving image features without introducing artifact and distortion is a major challenge in ultrasound image restoration. In this paper, we propose a multiframe-based adaptive…

Image and Video Processing · Electrical Eng. & Systems 2021-09-30 Jayanta Dey , Md. Kamrul Hasan

I propose a superoscillation measurement method for subdiffraction incoherent optical sources, with potential applications in astronomy, remote sensing, fluorescence microscopy, and spectroscopy. The proposal, based on coherent optical…

Quantum Physics · Physics 2022-10-10 Mankei Tsang

Optical phase-insensitive heterodyne (beat-note) detection, which measures the relative phase of two beams at different frequencies through their interference, is a key sensing technology for various spatial/temporal measurements, such as…

Quantum Physics · Physics 2024-05-20 Keitaro Anai , Yutaro Enomoto , Hiroto Omura , Koji Nagano , Kiwamu Izumi , Mamoru Endo , Shuntaro Takeda

We demonstrate that accurate computation of the spectral proper orthogonal decomposition (SPOD) critically depends on the choice of frequency resolution. Using both artificially generated data and large-eddy simulation data of a turbulent…

Fluid Dynamics · Physics 2024-02-27 Liam Heidt , Tim Colonius

Like the ordinary power spectrum, higher-order spectra (HOS) describe signal properties that are invariant under translations in time. Unlike the power spectrum, HOS retain phase information from which details of the signal waveform can be…

Signal Processing · Electrical Eng. & Systems 2019-08-27 Christopher K. Kovach , Matthew A. Howard

Passive monitoring of acoustic or radio sources has important applications in modern convenience, public safety, and surveillance. A key task in passive monitoring is multiobject tracking (MOT). This paper presents a Bayesian method for…

Signal Processing · Electrical Eng. & Systems 2024-02-29 Wenyu Zhang , Florian Meyer

Moving object detection (MOD) in remote sensing is significantly challenged by low resolution, extremely small object sizes, and complex noise interference. Current deep learning-based MOD methods rely on probability density estimation,…

Computer Vision and Pattern Recognition · Computer Science 2025-04-15 Jinyue Zhang , Xiangrong Zhang , Zhongjian Huang , Tianyang Zhang , Yifei Jiang , Licheng Jiao

We demonstrate accurate phase measurement from low photon level interference data using a constrained optimization method that takes into account the expected redundancy in the unknown phase function. This approach is shown to have…

Quantum Physics · Physics 2015-06-23 Mandeep Singh , Kedar Khare , Anand Kumar Jha , Shashi Prabhakar , R. P. Singh

The noise dynamics of an Optical Frequency Comb (OFC) based on a mode-locked Ti-Sapphire laser is analyzed in terms of noise modes. A spectrally resolved multipixel homodyne detection enables the simultaneous measurement of the amplitude…

Instrumentation and Detectors · Physics 2021-08-04 Matthieu Ansquer , Valérian Thiel , Syamsundar De , Bérengère Argence , Gregory Gredat , Fabien Bretenaker , Nicolas Treps

The Depth from Defocus (DFD) imaging technique for measuring the size and number concentration of particles in a dispersed two-phase flow has up to now been restricted to relatively sparse particle densities and to identifying only…

Fluid Dynamics · Physics 2024-04-01 Rixin Xua , Zuojie Huanga , Wenchao Gonga , Wu Zhoua , Cameron Tropea

Orbital angular momentum (OAM) recognition of vortex beams is critical for applications ranging from optical communications to quantum technologies. However, conventional approaches designed for free-space propagation struggle when light…

Large-format (sub)millimeter wavelength imaging arrays are best operated in scanning observing modes rather than traditional position-switched (chopped) modes. The choice of observing mode is critical for isolating source signals from…

Astrophysics · Physics 2014-11-18 A. Kovacs

We present a technique for binary spatial mode demultiplexing, using a double-clad fiber coupler as an optical mode sorter, for hypothesis testing for one or two point sources in an incident optical field. By directly coupling an optical…

A major limitation of transient optical spectroscopy is that relatively high laser fluences are required to enable broadband, multichannel detection with acceptable signal-to-noise levels. Under typical experimental conditions, many…

Optics · Physics 2023-05-03 Siedah J. Hall , Peter J. Budden , Anne Zats , Matthew Y. Sfeir

We derive the quantum noise limit for the optical beam displacement of a TEM00 mode. Using a multimodal analysis, we show that the conventional split detection scheme for measuring beam displacement is non-optimal with 80% efficiency. We…

Quantum Physics · Physics 2009-11-10 Magnus T. L. Hsu , Vincent Delaubert , Ping Koy Lam , Warwick Bowen

We consider sensor array imaging for simultaneous noise blended sources. We study a migration imaging functional and we analyze its sensitivity to singular perturbations of the speed of propagation of the medium. We consider two kinds of…

Analysis of PDEs · Mathematics 2012-10-09 Ennio Fedrizzi

In this paper, a sparse-based method for the estimation of the parameters of multidimensional ($R$-D) modal (harmonic or damped) complex signals in noise is presented. The problem is formulated as $R$ simultaneous sparse approximations of…

Information Theory · Computer Science 2015-11-02 Souleymen Sahnoun , El-Hadi Djermoune , David Brie , Pierre Comon

Semantic objects are unevenly distributed over images. In this paper, we study the spatial disequilibrium problem of modern object detectors and propose to quantify this ``spatial bias'' by measuring the detection performance over zones.…

Computer Vision and Pattern Recognition · Computer Science 2023-01-18 Zhaohui Zheng , Yuming Chen , Qibin Hou , Xiang Li , Ming-Ming Cheng