English
Related papers

Related papers: Sky reconstruction for the Tianlai cylinder array

200 papers

In this paper, we consider the problem of reconstructing piecewise smooth functions to high accuracy from nonuniform samples of their Fourier transform. We use the framework of nonuniform generalized sampling (NUGS) to do this, and to…

Numerical Analysis · Mathematics 2014-10-02 Ben Adcock , Milana Gataric , Anders C. Hansen

Consider the incidence of a time-harmonic electromagnetic plane wave onto a biperiodic dielectric grating, where the surface is assumed to be a small and smooth perturbation of a plane. The diffraction is modeled as a transmission problem…

Numerical Analysis · Mathematics 2017-08-02 Xue Jiang , Peijun Li

Geometry reconstruction of textureless, non-Lambertian objects under unknown natural illumination (i.e., in the wild) remains challenging as correspondences cannot be established and the reflectance cannot be expressed in simple analytical…

Computer Vision and Pattern Recognition · Computer Science 2023-10-27 Kohei Yamashita , Shohei Nobuhara , Ko Nishino

The fundamental mechanism driving MIMO beamforming is the relative phases of signals departing the transmit array and arriving at the receive array. If a propagation channel affects all transmitted signals equally, the relative phases are a…

Signal Processing · Electrical Eng. & Systems 2026-01-21 Oliver Kirkpatrick , Santiago Ozafrain , Christopher Gilliam , Beth Jelfs

Higher spatial resolution and larger imaging scene are always the goals pursued by advanced space-borne SAR system.High resolution and wide swath SAR imaging can provide more information about the illuminated scene of interest on one…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Xinhua Mao

We investigate phaseless inverse scattering problem for the Schr\"odinger equation and develop reconstruction methods based on the inverse Born series (IBS). We consider three types of phaseless data: the far-field total field, the total…

Mathematical Physics · Physics 2026-05-25 John C. Schotland , Shenwen Yu

We present a method for the reconstruction of ion kinetic energy distributions from ion time-of-flight mass spectra through ion trajectory simulations. In particular, this method is applicable to complicated spectrometer geometries with…

Atomic and Molecular Clusters · Physics 2024-05-22 Aaron Ngai , Katrin Dulitz , Sebastian Hartweg , Janine Franz , Marcel Mudrich , Frank Stienkemeier

We obtain new inversion formulas for the Funk type transforms of two kinds associated to spherical sections by hyperplanes passing through a common point $A$ which lies inside the n-dimensional unit sphere or on the sphere itself.…

Functional Analysis · Mathematics 2018-10-23 B. Rubin

Wide-field images made by radio interferometers are invariably affected by direction-dependent systematic effects such as the ionosphere or the beam pattern. Calibration along a set of discrete directions in the sky is the default technique…

Instrumentation and Methods for Astrophysics · Physics 2026-02-06 Sebastiaan van der Tol , Sarod Yatawatta , Bram Veenboer , David Rafferty

The large-angle, low multipole cosmic microwave background (CMB) provides a unique view of the largest angular scales in the Universe. Study of these scales is hampered by the facts that we have only one Universe to observe, only a few…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

In this paper, a reconstruction method for the spatially distributed dielectric constant of a medium from the back scattering wave field in the frequency domain is considered. Our approach is to propose a globally convergent algorithm,…

Analysis of PDEs · Mathematics 2016-03-01 Michael V. Klibanov , Loc H. Nguyen , Anders Sullivan , Lam Nguyen

The spatial-frequency coverage of a radio interferometer is increased by combining samples acquired at different times and observing frequencies. However, astrophysical sources often contain complicated spatial structure that varies within…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 U. Rau

We propose a scheme for imaging periodic surfaces using a superlens. By employing an inverse scattering model and the transformed field expansion method, we derive an approximate reconstruction formula for the surface profile, assuming…

Numerical Analysis · Mathematics 2024-03-05 Peijun Li , Yuliang Wang

We investigate super-resolution methods for image reconstruction from data provided by a family of scanning instruments like the Herschel observatory. To do this, we constructed a model of the instrument that faithfully reflects the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 F. Orieux , J. -F. Giovannelli , T. Rodet , A. Abergel , H. Ayasso , M. Husson

The lensing signals involved in CMB polarization maps have already been measured with ground-based experiments such as SPTpol and POLARBEAR, and would become important as a probe of cosmological and astrophysical issues in the near future.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Toshiya Namikawa , Ryo Nagata

We calculate the light transmission by a subwavelength plasmonic array using the boundary element method for parallel cylinders with different cross-sections: circular or elliptic with axes ratio 4:1. We demonstrate that the plasmonic…

Optics · Physics 2022-12-13 Anton Nemykin , Leonid Frumin , David Shapiro

This paper introduces a new algorithm for accurately reconstructing two smooth orthogonal surfaces by processing ultrasonic data. The proposed technique is based on a preliminary analysis of a waveform energy indicator in order to classify…

Robotics · Computer Science 2014-01-22 Nicola Ivan Giannoccaro , Giovanni Indiveri , Luigi Spedicato

Design and reconstruction of 2d and 3d photonic structures are usually carried out by forward simulations combined with optimization or intuition. Reconstruction by means of layer-stripping has been applied in seismic processing as well as…

Optics · Physics 2011-05-19 Marte P. Hatlo Andresen , Harald E. Krogstad , Johannes Skaar

We introduce a new technique for imaging the polarized radio sky using interferometric data. The new approach, which we call Faraday synthesis, combines aperture and rotation measure synthesis imaging and deconvolution into a single…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. R. Bell , T. A. Enßlin

Model-free reconstruction of the bifurcation diagrams of Chua's circuits by the technique of parameter-aware reservoir computing is investigated. We demonstrate that: (1) reservoir computer can be utilized as a noise filter to recover the…

Disordered Systems and Neural Networks · Physics 2023-09-20 Haibo Luo , Yao Du , Huawei Fan , Xuan Wang , Jianzhong Guo , Xingang Wang