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Measurements of transverse profiles using Ionization Profile Monitors (IPMs) for high brightness beams are affected by the electromagnetic field of the beam. This interaction may cause a distortion of the measured profile shape despite…

Accelerator Physics · Physics 2019-05-22 Dominik Vilsmeier , Mariusz Sapinski , Rahul Singh

We present a Bayesian algorithm to combine optical imaging of unresolved objects from distinct epochs and observation platforms for orbit determination and tracking. By propagating the non-Gaussian uncertainties we are able to optimally…

Instrumentation and Methods for Astrophysics · Physics 2016-09-26 Michael D. Schneider , William A. Dawson

Rotating Synthetic Aperture Radar (ROSAR) can generate a 360$^\circ$ image of its surrounding environment using the collected data from a single moving track. Due to its non-linear track, the Back-Projection Algorithm (BPA) is commonly used…

Signal Processing · Electrical Eng. & Systems 2023-09-18 Wei Zhao , Cai Wen , Quan Yuan , Rong Zheng

Low-noise phased arrays are essential for the next generation of microwave and submillimetre wave astronomy. We analyze their behaviour from a functional perspective, and show that their operation is intimately related to the mathematical…

Astrophysics · Physics 2007-07-12 S. Withington , G. Saklatvala , M. P. Hobson

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

Calibration of radio interferometric observations becomes increasingly difficult towards lower frequencies. Below ~300 MHz, spatially variant refractions and propagation delays of radio waves traveling through the ionosphere cause phase…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 H. T. Intema , S. van der Tol , W. D. Cotton , A. S. Cohen , I. M. van Bemmel , H. J. A. Rottgering

Satellite imagery solutions are widely used to study and monitor different regions of the Earth. However, a single satellite image can cover only a limited area. In cases where a larger area of interest is studied, several images must be…

Artificial Intelligence · Computer Science 2023-12-08 Manuel Combarro Simón , Pierre Talbot , Grégoire Danoy , Jedrzej Musial , Mohammed Alswaitti , Pascal Bouvry

We propose a novel algorithm for image reconstruction in radio interferometry. The ill-posed inverse problem associated with the incomplete Fourier sampling identified by the visibility measurements is regularized by the assumption of…

Instrumentation and Methods for Astrophysics · Physics 2012-10-12 R. E. Carrillo , J. D. McEwen , Y. Wiaux

Intensity mapping is a promising technique for surveying the large scale structure of our Universe from $z=0$ to $z \sim 150$, using the brightness temperature field of spectral lines to directly observe previously unexplored portions of…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Adrian Liu , Yunfan Zhang , Aaron R. Parsons

Radar interferometry usually exploits two complex-valued radar images with the same resolution to extract terrain elevation information. This paper considers the interferometry using two radar images with different resolutions, which we…

Information Theory · Computer Science 2018-12-14 Huizhang Yang , Chengzhi Chen , Shengyao Chen , Feng Xi , Zhong Liu

We propose a new algorithm, for parameter estimation that is applicable to imaging using moving and synthetic aperture arrays. The new method results in higher resolution and more accurate estimation than commonly used methods when strong…

Instrumentation and Methods for Astrophysics · Physics 2010-08-31 Ronny Levanda , Amir Leshem

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

Optics · Physics 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

In near-infrared bands, co-adding and tiling of astronomical imaging datasets require a sufficiently high calibration quality (flat fielding, background subtraction). Here we present a complete workflow for obtaining imaging mosaics with…

Instrumentation and Methods for Astrophysics · Physics 2021-12-06 Kirill Grishin , Igor Chilingarian

Observations at radio wavelengths address key problems in astrophysics, astrobiology, and lunar structure including the first light in the Universe (the Epoch of Reionization), the presence of magnetic fields around extrasolar planets,…

Astrophysics · Physics 2007-05-23 J. Lazio , R. J. Macdowall , J. Burns , L. Demaio , D. L. Jones , K. W. Weiler

Interferometric measurements with arrays of radio antennas are a powerful and widely used technique in astronomy. Recently, this technique has been revisited for the reconstruction of extensive air showers [1]. This radio-interferometric…

Instrumentation and Methods for Astrophysics · Physics 2022-12-16 Felix Schlüter , Tim Huege

Radio astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of the instrumental characteristics (primary beam) and foreground (ionospheric/atmospheric) effects.…

Instrumentation and Methods for Astrophysics · Physics 2011-11-24 Juan M. Uson , William D. Cotton

We present an approach for improving spatial frequency sampling in active incoherent millimeter-wave (AIM) imaging systems using frequency diversity. AIM imaging relies on active transmission of spatio-temporally incoherent signals to…

Signal Processing · Electrical Eng. & Systems 2025-03-12 Jorge R. Colon-Berrios , Jeffrey A. Nanzer

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

We introduce a novel algorithm for nonlinear processing of data gathered by an active array of sensors which probes a medium with pulses and measures the resulting waves. The algorithm is motivated by the application of array imaging. We…

Numerical Analysis · Mathematics 2019-02-20 Liliana Borcea , Vladimir Druskin , Alexander V. Mamonov , Mikhail Zaslavsky

Imaging of planets is very difficult, due to the glare from their nearby, much brighter suns. Static and slowly-evolving aberrations are the limiting factors, even after application of adaptive optics. The residual speckle pattern is highly…

Astrophysics · Physics 2009-11-13 Erez N. Ribak , Szymon Gladysz
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