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Related papers: Direction-Dependent Faraday Synthesis

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Fourier imaging is an indirect imaging method which records the diffraction pattern of the object scene coherently in the focal plane of the imaging system and reconstructs the image using computational resources. The spatial resolution,…

Optics · Physics 2023-06-05 Hui Yuan , Alvydas Lisauskas , Mark D. Thomson , Hartmut G. Roskos

Paper I of the series re-derived the radio interferometry measurement equation (RIME) from first principles, and extended the Jones formalism to the full-sky case, incorporating direction-dependent effects (DDEs). This paper aims to…

Instrumentation and Methods for Astrophysics · Physics 2011-02-07 Oleg M. Smirnov

We introduce the construction of polarized intensity cubes $P$(RA, Dec, $\Phi$) and their visualization as movies, as a powerful technique for interpreting Faraday structure. $P$ is constructed from maps of peak polarized intensity P(RA,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-24 Lawrence Rudnick , Craig Anderson , William D. Cotton , Alice Pasetto , Emma Alexander , Mehrnoosh Tahani

A new near-to-far-field transformation algorithm for three-dimensional finite-different time-domain is presented in this article. This new approach is based directly on the polarization current of the scatterer, not the scattered near…

Optics · Physics 2015-05-13 Yong Zeng , Jerome V. Moloney

In this paper we consider the fundamental operations dilation and erosion of mathematical morphology. Many powerful image filtering operations are based on their combinations. We establish homomorphism between max-plus semi-ring of integers…

Image and Video Processing · Electrical Eng. & Systems 2023-05-05 Vivek Sridhar , Keyvan Shahin , Michael Breuß , Marc Reichenbach

Recent progress in synthetic aperture sonar (SAS) technology and processing has led to significant advances in underwater imaging, outperforming previously common approaches in both accuracy and efficiency. There are, however, inherent…

Numerical Analysis · Mathematics 2017-06-28 John McKay , Anne Gelb , Vishal Monga , Raghu Raj

We present a filtering technique that can be applied to individual baselines of wide-bandwidth, wide-field interferometric data to geometrically select regions on the celestial sphere that contain primary calibration sources. The technique…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Aaron R. Parsons , Donald C. Backer

The study of astronomical phenomena through ground-based observations is always challenged by the distorting effects of Earth's atmosphere. Traditional methods of post-facto image correction, essential for correcting these distortions,…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 A. Asensio Ramos

Interferometric Synthetic Aperture Radar (InSAR) Imaging methods are usually based on algorithms of match-filtering type, without considering the scene's characteristic, which causes limited imaging quality. Besides, post-processing steps…

Signal Processing · Electrical Eng. & Systems 2022-10-07 Xu Zhan , Xiaoling Zhang , Shunjun Wei , Jun Shi

The degree to which the formation and evolution of clouds and filaments in the interstellar medium is regulated by magnetic fields remains an open question. Yet the fundamental properties of the fields (strength and 3D morphology) are not…

Astrophysics of Galaxies · Physics 2020-10-21 Stefan Reissl , Amelia M. Stutz , Ralf S. Klessen , Daniel Seifried , Stefanie Walch

Spatial resolution of most imaging devices is fundamentally restricted by diffraction. This limitation is manifested in the loss of high spatial frequency information contained in evanescent waves. As a result, conventional far-field optics…

Optics · Physics 2010-03-16 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

The desire for wide-field of view, large fractional bandwidth, high sensitivity, high spectral and temporal resolution has driven radio interferometry to the point of big data revolution where the data is represented in at least three…

Instrumentation and Methods for Astrophysics · Physics 2020-09-30 M. Atemkeng , O. Smirnov , C. Tasse , G. Foster , S. Makhathini

Detecting 3D objects accurately from multi-view 2D images is a challenging yet essential task in the field of autonomous driving. Current methods resort to integrating depth prediction to recover the spatial information for object query…

Computer Vision and Pattern Recognition · Computer Science 2025-10-20 Haisheng Su , Junjie Zhang , Feixiang Song , Sanping Zhou , Wei Wu , Nanning Zheng , Junchi Yan

Inverse problems generally require a regularizer or prior for a good solution. A recent trend is to train a convolutional net to denoise images, and use this net as a prior when solving the inverse problem. Several proposals depend on a…

Computer Vision and Pattern Recognition · Computer Science 2023-07-12 Kyle Luther , H. Sebastian Seung

Aims : We describe MS-MFS, a multi-scale multi-frequency deconvolution algorithm for wide-band synthesis-imaging, and present imaging results that illustrate the capabilities of the algorithm and the conditions under which it is feasible…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Urvashi Rau , Tim J. Cornwell

We present a microscope paradigm that performs differential interference imaging with high sensitivity via optical amplification and radio-frequency (RF) heterodyne detection. This method, termed differentially-enhanced sideband imaging via…

Optics · Physics 2015-03-26 A. M. Fard , A. Mahjoubfar , B. Jalali

Active galactic nuclei (AGN) play an integral role in galaxy formation and evolution by influencing galaxies and their environments through radio jet feedback. Historically, interpreting observations of radio galaxies and quantifying radio…

Recent developments in fluorescence microscopy allow capturing high-resolution 3D images over time for living model organisms. To be able to image even large specimens, techniques like multi-view light-sheet imaging record different…

Image and Video Processing · Electrical Eng. & Systems 2021-08-29 Canyu Yang , Dennis Eschweiler , Johannes Stegmaier

Multi contrast MRI synthesis is inherently challenging due to the complex and nonlinear relationships among different contrasts. Each MRI contrast highlights unique tissue properties, but their complementary information is difficult to…

Image and Video Processing · Electrical Eng. & Systems 2025-06-23 Sanuwani Dayarathna , Himashi Peiris , Kh Tohidul Islam , Tien-Tsin Wong , Zhaolin Chen

Change detection in heterogeneous remote sensing images is crucial for disaster damage assessment. Recent methods use homogenous transformation, which transforms the heterogeneous optical and SAR remote sensing images into the same feature…

Computer Vision and Pattern Recognition · Computer Science 2020-04-09 Xiao Jiang , Gang Li , Yu Liu , Xiao-Ping Zhang , You He