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Related papers: Backward Propagation

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The radio wave propagation channel is central to the performance of wireless communication systems. In this paper, we introduce a novel machine learning-empowered methodology for wireless channel modeling. The key ingredients include a…

Signal Processing · Electrical Eng. & Systems 2024-06-26 Ge Cao , Zhen Peng

An iterative method is derived for image reconstruction. Among other attributes, this method allows constraints unrelated to the radiation measurements to be incorporated into the reconstructed image. A comparison is made with the widely…

Computational Physics · Physics 2011-01-06 Clinton DeW. Van Siclen

Wavefront shaping is a powerful method to refocus light through a scattering medium. Its application to large spectral bandwidths or multiple wavelengths refocusing for nonlinear bio-imaging in-depth is however limited by spectral…

It has been recently proven that natural images exhibit scaling properties analogue to those of turbulent flows. These properties allow regarding each image as a multifractal object, for which its most singular manifold conveys the most of…

Statistical Mechanics · Physics 2007-05-23 Antonio Turiel , Angela del Pozo

The Helmholtz equation can be written as coupled equations for the amplitude and phase. By considering spatial phase distributions corresponding to reflectionless wave propagation in the plane and solving for the amplitude in terms of this…

Optics · Physics 2018-05-23 Chris King , Simon Horsley , Thomas Philbin

We present an analysis of enhanced wave transmission through random media with mirror symmetry about a reflecting barrier. The mathematical model is the acoustic wave equation and we consider two setups, where the wave propagation is along…

Mathematical Physics · Physics 2024-01-30 Liliana Borcea , Josselin Garnier

Imaging with optical resolution through highly scattering media is a long sought-after goal with important applications in deep tissue imaging. Although being the focus of numerous works, this goal was considered impractical until recently.…

Optics · Physics 2012-02-10 Ori Katz , Eran Small , Yaron Silberberg

Terahertz (THz) tomography is a rather novel technique for nondestructive testing that is particularly suited for the testing of plastics and ceramics. Previous publications showed a large variety of conventional algorithms adapted from…

Numerical Analysis · Mathematics 2016-01-19 Jens Tepe , Thomas Schuster , Benjamin Littau

Received signal strength based radio tomographic imaging is a popular device-free indoor localization method which reconstructs the spatial loss field of the environment using measurements from a dense wireless network. Existing methods…

Emerging Technologies · Computer Science 2016-04-12 Hüseyin Yiğitler , Riku Jäntti , Ossi Kaltiokallio , Neal Patwari

A classical problem in acoustic (and electromagnetic) scattering concerns the evaluation of the Green's function for the Helmholtz equation subject to impedance boundary conditions on a half-space. The two principal approaches used for…

Numerical Analysis · Mathematics 2012-11-28 Michael O'Neil , Leslie Greengard , Andras Pataki

A phenomenological method is developed to consider elastic guided wave propagation in complex curved waveguides. The theory on guided wave propagation in hollow circular cylinders is used in order to verify the method. The results are…

Classical Physics · Physics 2012-09-03 E. Khajeh , L. Breon , J. L. Rose

The discovery of robust transport via topological states in electronic, photonic and phononic materials has deepened our understanding of wave propagation in condensed matter with prospects for critical applications of engineered…

Mesoscale and Nanoscale Physics · Physics 2020-03-04 Yuhao Kang , Azriel Z. Genack

An overlapped continuous model framework, for the Helmholtz wave propagation problem in unbounded regions comprising bounded heterogeneous media, was recently introduced and analyzed by the authors ({\tt J. Comput. Phys., {\bf 403}, 109052,…

Numerical Analysis · Mathematics 2021-06-30 V. Domínguez , M. Ganesh

We present a multiscale approach for identifying features in ocean beds by solving inverse problems in high frequency seafloor acoustics. The setting is based on Sound Navigation And Ranging (SONAR) imaging used in scientific, commercial,…

Numerical Analysis · Mathematics 2017-04-05 Bjorn Engquist , Christina Frederick , Quyen Huynh , Haomin Zhou

We consider the inverse problem of reconstructing general solutions to the Helmholtz equation on some domain $\Omega$ from their values at scattered points $x_1,\dots,x_n\subset \Omega$. This problem typically arises when sampling acoustic…

Numerical Analysis · Mathematics 2014-04-04 Gilles Chardon , Albert Cohen , Laurent Daudet

It is demonstrated that the wavelets can be used to considerably speed up simulations of the wave packet propagation in multiscale systems. Extremely high efficiency is obtained in the representation of both bound and continuum states. The…

Computational Physics · Physics 2009-11-07 Andrei G. Borisov , Sergei V. Shabanov

Incorporating wide-field considerations in interferometric imaging is of increasing importance for next-generation radio telescopes. Compressed sensing techniques for interferometric imaging have been extended to wide fields recently,…

Instrumentation and Methods for Astrophysics · Physics 2011-08-29 J. D. McEwen , Y. Wiaux

This paper is concerned with the multi-frequency factorization method for imaging the support of a wave-number-dependent source function. It is supposed that the source function is given by the inverse Fourier transform of some…

Numerical Analysis · Mathematics 2024-01-02 Hongxia Guo , Guanghui Hu

To design semiconductor-based optical devices, the optical properties of the used semiconductor materials must be precisely measured over a large band. Transmission spectroscopy stands out as an inexpensive and widely available method for…

Wave velocity is a key parameter for imaging complex media, but in vivo measurements are typically limited to reflection geometries, where only backscattered waves from short-scale heterogeneities are accessible. As a result, conventional…