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The sparse layouts of radio interferometers result in an incomplete sampling of the sky in Fourier space which leads to artifacts in the reconstructed images. Cleaning these systematic effects is essential for the scientific use of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-27 Kevin Schmidt , Felix Geyer , Stefan Fröse , Paul-Simon Blomenkamp , Marcus Brüggen , Francesco de Gasperin , Dominik Elsässer , Wolfgang Rhode

In optical metrology, grating-like structures are used as tools to evaluate the performance of lithographic techniques. In particular, several shape parameters characterize those structures. One of them, termed side-wall angle, suffers from…

Optics · Physics 2015-10-21 Luca Cisotto , Paul H. Urbach

For future mmWave mobile communication systems the use of analog/hybrid beamforming is envisioned be a key as- pect. The synthesis of beams is a key technology of enable the best possible operation during beamsearch, data transmission and…

Information Theory · Computer Science 2017-04-27 Kilian Roth , Josef A. Nossek

Radio interferometric data are used to estimate the sky brightness distributions in radio frequencies. Here we focus on estimators of the large-scale structure and the power spectrum of the sky brightness distribution inferred from radio…

Instrumentation and Methods for Astrophysics · Physics 2019-04-17 Prasun Dutta , Meera Nandakumar

In this study, we consider a remote estimation system that estimates a time-varying target based on sensor data transmitted over wireless channel. Due to transmission errors, some data packets fail to reach the receiver. To mitigate this,…

Signal Processing · Electrical Eng. & Systems 2025-01-07 Sirin Chakraborty , Yin Sun

We generalize the technique of fringe-rate filtering, whereby visibilities measured by a radio interferometer are re-weighted according to their temporal variation. As the Earth rotates, radio sources traverse through an interferometer's…

Instrumentation and Methods for Astrophysics · Physics 2016-03-21 Aaron R. Parsons , Adrian Liu , Zaki S. Ali , Carina Cheng

A conventional method to determine beam parameters is using the profile measurements and converting them into the values of twiss parameters and beam emittance at a specified position. The beam information can be used to improve transverse…

Accelerator Physics · Physics 2015-07-14 Ji-Ho Jang , Hyo Jae Jang , Dong-O Jeon

In this paper we revisit the classical problem of estimating a signal as it impinges on a multi-sensor array. We focus on the case where the impinging signal's bandwidth is appreciable and is operating in a broadband regime. Estimating…

Signal Processing · Electrical Eng. & Systems 2023-12-08 Coleman DeLude , Mark A. Davenport , Justin Romberg

In this paper, we study the channel estimation problem in correlated massive multiple-input-multiple-output (MIMO) systems with a reduced number of radio-frequency (RF) chains. Importantly, other than the knowledge of channel correlation…

Information Theory · Computer Science 2021-11-10 Javad Mirzaei , Shahram ShahbazPanahi , Foad Sohrabi , Raviraj Adve

The problem of joint design of transmit waveforms and receive filters is desirable in many application scenarios of multiple-input multiple-output (MIMO) radar systems. In this paper, the joint design problem is investigated under the…

Signal Processing · Electrical Eng. & Systems 2021-02-11 Huanyu Zhang , Ziping Zhao

We introduce an optimal transport-based model for learning a metric tensor from cross-sectional samples of evolving probability measures on a common Riemannian manifold. We neurally parametrize the metric as a spatially-varying matrix field…

Machine Learning · Computer Science 2023-03-08 Christopher Scarvelis , Justin Solomon

Radial basis functions (RBFs) play an important role in function interpolation, in particular in an arbitrary set of interpolation nodes. The accuracy of the interpolation depends on a parameter called the shape parameter. There are many…

Numerical Analysis · Mathematics 2025-08-27 Maria Han Veiga , Faezeh Nassajian Mojarrad , Fatemeh Nassajian Mojarrad

We describe a "spatio-spectral" deconvolution algorithm for wide-band imaging in radio interferometry. In contrast with the existing multi-frequency reconstruction algorithms, the proposed method does not rely on a model of the…

Instrumentation and Methods for Astrophysics · Physics 2016-03-01 André Ferrari , Jérémy Deguignet , Chiara Ferrari , David Mary , Antony Schutz , Oleg Smirnov

We propose an inexact optimization algorithm on Riemannian manifolds, motivated by quadratic discrimination tasks in high-dimensional, low-sample-size (HDLSS) imaging settings. In such applications, gradient evaluations are often biased due…

Optimization and Control · Mathematics 2025-07-08 Uday Talwar , Meredith K. Kupinski , Afrooz Jalilzadeh

Millimeter-wave (mmWave) and terahertz (THz) communication systems adopt large antenna arrays to ensure adequate receive signal power. However, adjusting the narrow beams of these antenna arrays typically incurs high beam training overhead…

Information Theory · Computer Science 2023-02-15 Shoaib Imran , Gouranga Charan , Ahmed Alkhateeb

We report on a numerical evaluation of the statistical bootstrap as a technique for radio-interferometric imaging fidelity assessment. The development of a fidelity assessment technique is an important scientific prerequisite for automated…

Astrophysics · Physics 2009-11-10 Athol Kemball , Adam Martinsek

Radio Interferometry is an essential method for astronomical observations. Self-calibration techniques have increased the quality of the radio astronomical observations (and hence the science) by orders of magnitude. Recently, there is a…

Astrophysics · Physics 2008-11-03 Sarod Yatawatta , Saleem Zaroubi , Ger de Bruyn , Leon Koopmans , Jan Noordam

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

This paper studies a multiple-input multiple-output (MIMO) radar system for sensing the unknown and random angular location (angle) of a point target, based on the target-reflected echo signals and known prior distribution information about…

Information Theory · Computer Science 2026-04-24 Yizhuo Wang , Shuowen Zhang

Channel estimation is challenging in multi-antenna communication systems, because of the large number of parameters to estimate. One way of facilitating this task is to use a physical model describing the multiple paths constituting the…

Signal Processing · Electrical Eng. & Systems 2019-02-20 Luc Le Magoarou , Stéphane Paquelet
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