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Related papers: Wide field imaging for the Square Kilometre Array

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We develop sparse array receive beamformer design methods achieving maximum signal-to-interference plus noise ratio (MaxSINR) for wideband sources and jammers. Both tapped delay line (TDL) filtering and the DFT realizations to wideband…

Signal Processing · Electrical Eng. & Systems 2020-11-16 Syed A. Hamza , Moeness Amin

We investigate the imaging performance of an interferometric array in the case of wide field, high resolution, narrow band, snapshot imaging. We find that, when uv-cell sizes are sufficiently small (ie. image sizes are sufficiently large),…

Instrumentation and Methods for Astrophysics · Physics 2020-07-03 C. L. Carilli , E. Murphy , V. Rosero , K. Mooley , E. Jimenez-Andrade , K. Golap , B. Butler

This paper studies hybrid beamforming for active sensing applications, such as millimeter-wave or ultrasound imaging. Hybrid beamforming can substantially lower the cost and power consumption of fully digital sensor arrays by reducing the…

Signal Processing · Electrical Eng. & Systems 2020-12-30 Robin Rajamäki , Sundeep Prabhakar Chepuri , Visa Koivunen

Microarray technology is a new and powerful tool for the concurrent monitoring of a large number of gene expressions. Each microarray experiment produces hundreds of images. Each digital image requires a large storage space. Hence,…

Image and Video Processing · Electrical Eng. & Systems 2023-03-21 Anahita Banaei , Shadrokh Samavi , Ebrahim Nasr Esfahani

While characterization of coherent wavefields is essential to laser, x-ray and electron imaging, sensors measure the squared magnitude of the field, rather than the field itself. Holography or phase retrieval must be used to characterize…

Image and Video Processing · Electrical Eng. & Systems 2020-12-10 David J. Brady , Timothy J. Schulz , Chengyu Wang

A method of binaural rendering from microphone array signals of arbitrary geometry is proposed. To reproduce binaural signals from microphone array recordings at a remote location, a spherical microphone array is generally used for…

Audio and Speech Processing · Electrical Eng. & Systems 2024-06-19 Naoto Iijima , Shoichi Koyama , Hiroshi Saruwatari

Light-based synthetic aperture (SA) imaging methods, such as Fourier Ptychography, have brought breakthrough high-resolution wide-field-of-view imaging capabilities to microscopy. While these technologies promise similar improvements in…

Optics · Physics 2025-09-29 Janith B. Senanayaka , Christopher A. Metzler

In this paper, a new sampling scheme of the near field radiated by a planar source is proposed and assessed. More in detail, the paper shows a uniform sampling criterion that allows representing the near field over a plane with a number of…

Signal Processing · Electrical Eng. & Systems 2024-02-13 Raffaele Moretta , Fabio Pascariello , Giovanni Petraglia , Maurizio Feo , Maria Antonia Maisto

The design of an interferometric array should allow optimal instrumental response regarding all possible source positions, times of integration and scientific goals. It should also take into account constraints such as forbidden regions on…

Astrophysics · Physics 2009-11-07 F. Boone

The light field camera is useful for computer graphics and vision applications. Calibration is an essential step for these applications. After calibration, we can rectify the captured image by using the calibrated camera parameters.…

Computer Vision and Pattern Recognition · Computer Science 2014-07-17 Yichao Xu , Kazuki Maeno , Hajime Nagahara , Rin-ichiro Taniguchi

I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 T. D. Carozzi

In radio astronomy, holography is a commonly used technique to create an image of the electric field distribution in the aperture of a dish antenna. The image is used to detect imperfections in the reflector surface. Similarly, holography…

Instrumentation and Methods for Astrophysics · Physics 2021-06-09 U. Kiefner , R. B. Wayth , D. B. Davidson , M. Sokolowski

Optical approaches to fluorescent, spectroscopic, and morphological imaging have made exceptional advances in the last decade. Super-resolution imaging and wide-field multiphoton imaging are now underpinning major advances across the…

Equipped with a suitable optical relay system, telescopes employing low-cost fixed primary mirrors could point and track while delivering high-quality images to a fixed location. Such an optical tracking system would enable liquid-mirror…

Astrophysics · Physics 2009-11-06 Paul Hickson

A fast full-wave simulation technique is presented for the analysis of large irregular planar arrays of identical 3-D metallic antennas. The solution method relies on the Macro Basis Functions (MBF) approach and an interpolatory technique…

Instrumentation and Methods for Astrophysics · Physics 2018-05-09 Ha Bui-Van , Jens Abraham , Michel Arts , Quentin Gueuning , Christopher Raucy , David Gonzalez-Ovejero , Eloy de Lera Acedo , Christophe Craeye

A simple, yet general, formalism for the optimized linear combination of astrophysical images is constructed and demonstrated. The formalism allows the user to combine multiple undersampled images to provide oversampled output at high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Barnaby Rowe , Christopher Hirata , Jason Rhodes

The square and rectangular shape of the pixels in the digital images for sensing and display purposes introduces several inaccuracies in the representation of digital images. The major disadvantage of square pixel shapes is the inability to…

Computer Vision and Pattern Recognition · Computer Science 2015-06-23 Sherin Sugathan , Reshma Scaria , Alex Pappachen James

We present a new multiband extension to the crowdsource photometric pipeline, enabling simultaneous fitting across multiple imaging bands in crowded fields. The core idea is that multiple images of the same part of the sky should have the…

Instrumentation and Methods for Astrophysics · Physics 2026-04-29 Jayashree Behera , Edward F. Schlafly , Aaron M. Meisner , Lucas Napolitano

Beam squint, the frequency-dependent shift of the main beam, poses a major challenge for wideband antenna arrays. This paper focuses on the beam squint effects in super wideband (SW) systems, where high mutual coupling (MC) effects are…

Signal Processing · Electrical Eng. & Systems 2026-04-17 Sachitha C. Bandara , Peter J. Smith , Erfan Khordad , Pawel Dmochowski , Robin Evans , Rajitha Senanayake

Phased arrays, commonly used in IEEE 802.11ad and 5G radios, are capable of focusing radio frequency signals in a specific direction or a spatial region. Beamforming achieves such directional or spatial concentration of signals and enables…

Signal Processing · Electrical Eng. & Systems 2024-10-30 Nitin Jonathan Myers , Robert W. Heath
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