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Related papers: Wide field imaging for the Square Kilometre Array

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Telescope arrays allow high-performance wide-field imaging systems to be built more quickly and at lower cost than conventional telescopes. Distributed aperture telescopes (the premier example of which is the Dragonfly Telephoto Array) are…

Instrumentation and Methods for Astrophysics · Physics 2022-09-16 Roberto G. Abraham , Pieter G. van Dokkum , Deborah M. Lokhorst , Seery Chen , Qing Liu , Michael L. Rice , E. Lynn Rice

Broadband beamforming is a technique to obtain the signal with a wide range of frequencies. It maintains the signal integrity and spatial selectivity over frequencies. This is important in several applications such as microphone array,…

Signal Processing · Electrical Eng. & Systems 2020-03-03 Phan Le Son

Large-aperture coprime arrays (CAs) are expected to achieve higher sensing resolution than conventional dense arrays (DAs), yet with lower hardware and energy cost. However, existing CA far-field localization methods cannot be directly…

Signal Processing · Electrical Eng. & Systems 2024-11-05 Hongqiang Cheng , Changsheng You , Cong Zhou

The concept of Wavelength Frame Multiplication (WFM) was developed to extend the usable wavelength range on long pulse neutron sources for instruments using pulse shaping choppers. For some instruments, it is combined with a pulse shaping…

Instrumentation and Detectors · Physics 2013-07-18 D. Nekrassov , C. Zendler , K. Lieutenant

Ground-based astronomical observations at thermal infrared wavelengths face the problem of extracting the weak astronomical signal from the large and rapidly variable background flux. The observing strategy most commonly used, the so-called…

Astrophysics · Physics 2009-10-31 M. Bertero , P. Boccacci , M. Robberto

We investigate the problem of localizing multiple targets using a single set of measurements from a network of radar sensors. Such "single snapshot imaging" provides timely situational awareness, but can utilize neither platform motion, as…

Signal Processing · Electrical Eng. & Systems 2024-10-01 Anant Gupta , Ahmet Dundar Sezer , Upamanyu Madhow

The problem of 3D high-resolution imaging in automotive multiple-input multiple-output (MIMO) side-looking radar using a 1D array is considered. The concept of motion-enhanced snapshots is introduced for generating larger apertures in the…

Signal Processing · Electrical Eng. & Systems 2024-12-02 Sen Yuan , Francesco Fioranelli , Alexander Yarovoy

Hybrid beamforming via large antenna arrays has shown a great potential for increasing data rate in cellular networks by delivering multiple data streams simultaneously. In this paper, several beamforming design algorithms are proposed…

Information Theory · Computer Science 2018-02-06 Shahram Shahsavari , S. Amir Hosseini , Chris Ng , Elza Erkip

Adaptive subtraction is a key element in predictive multiple-suppression methods. It minimizes misalignments and amplitude differences between modeled and actual multiples, and thus reduces multiple contamination in the dataset after…

The Square Kilometer Array (SKA) would be the world's largest radio telescope with eventually over a square kilometer of collecting area. However, there are enormous challenges in its data processing. The using of modern distributed…

Instrumentation and Methods for Astrophysics · Physics 2021-06-02 Shoulin Wei , Kaida Luo , Feng Wang , Hui Deng , Ying Mei

Phase unwrapping is a key problem in many coherent imaging systems, such as synthetic aperture radar (SAR) interferometry. A general formulation for redundant integration of finite differences for phase unwrapping (Costantini et al., 2010)…

Other Computer Science · Computer Science 2018-05-04 Ravi Lanka

In coherent X-ray diffraction microscopy the diffraction pattern generated by a sample illuminated with coherent x-rays is recorded, and a computer algorithm recovers the unmeasured phases to synthesize an image. By avoiding the use of a…

The best beam steering directions are estimated through beam training, which is one of the most important and challenging tasks in millimeter-wave and sub-terahertz communications. Novel array architectures and signal processing techniques…

Signal Processing · Electrical Eng. & Systems 2020-07-20 Veljko Boljanovic , Han Yan , Chung-Ching Lin , Soumen Mohapatra , Deukhyoun Heo , Subhanshu Gupta , Danijela Cabric

Snapshot Multispectral Light-field Imaging (SMLI) is an emerging computational imaging technique that captures high-dimensional data (x, y, z, $\theta$, $\phi$, $\lambda$) in a single shot using a low-dimensional sensor. The accuracy of…

Signal Processing · Electrical Eng. & Systems 2025-09-03 Erqi Huang , John Restrepo , Xun Cao , Ivo Ihrke

Sparse arrays are popular for performance optimization while keeping the hardware and computational costs down. In this paper, we consider sparse arrays design method for wideband source operating in a wideband jamming environment.…

Signal Processing · Electrical Eng. & Systems 2019-12-09 Syed A. Hamza , Moeness G. Amin

This paper investigates the possibility of improving radio interferometric images using an algorithm inspired by an optical method known as "lucky imaging", which would give more weight to the best-calibrated visibilities used to make a…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 Etienne Bonnassieux , Cyril Tasse , Oleg Smirnov , Philippe Zarka

Unbiased sky background modeling is crucial for the analysis of deep wide-field images, but it remains a major challenge in low surface brightness astronomy. Traditional image processing algorithms are often designed to produce artificially…

Here the role and influence of aberrations in optical imaging systems employing partially coherent complex scalar fields is studied. Imaging systems require aberrations to yield contrast in the output image. For linear shift-invariant…

Optics · Physics 2015-06-30 Mario A. Beltran , Marcus J. Kitchen , T. Petersen , David M. Paganin

Several telescopes include large Deformable Mirrors (DM) located directly inside the telescope. These adaptive telescopes trigger new constraints for the calibration of the Adaptive Optics (AO) systems as they usually offer no access to an…

Instrumentation and Methods for Astrophysics · Physics 2019-01-10 C. T. Heritier , S. Esposito , T. Fusco , B. Neichel , S. Oberti , R. Briguglio , G. Agapito , A. Puglisi , E. Pinna , P. -Y. Madec

The process of wide-field synthesis imaging is explored, with the aim of understanding the implications of variable, polarised primary beams for forthcoming Epoch of Reionisation experiments. These experiments seek to detect weak signatures…

Instrumentation and Methods for Astrophysics · Physics 2012-06-05 Daniel A. Mitchell , Randall B. Wayth , Gianni Bernardi , Lincoln J. Greenhill , Stephen M. Ord