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Interferometry provides highly sensitive access to optical phase and is central to much of modern metrology and phase imaging methods. Conventional implementations, however, often face trade-offs between mechanical stability and…

Radio interferometry invariably suffers from an incomplete coverage of the spatial Fourier space, which leads to imaging artifacts. The current state-of-the-art technique is to create an image by Fourier-transforming the incomplete…

Instrumentation and Methods for Astrophysics · Physics 2024-12-19 F. Geyer , K. Schmidt , J. Kummer , M. Brüggen , H. W. Edler , D. Elsässer , F. Griese , A. Poggenpohl , L. Rustige , W. Rhode

Suitable shaping (in particular, flattening and broadening) of the laser beam has recently been proposed as an effective device to reduce internal (mirror) thermal noise in advanced gravitational wave interferometric detectors. Based on…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Vincenzo Pierro , Vincenzo Galdi , Giuseppe Castaldi , Innocenzo M. Pinto , Juri Agresti , Riccardo DeSalvo

Infrared space interferometers can surpass the spatial resolution limitations of single-dish space telescopes. However, stellar interferometers from space have not been realized because of technical difficulties. Two beams coming from…

Instrumentation and Methods for Astrophysics · Physics 2022-01-20 Taro Matsuo , Satoshi Ikari , Hirotaka Kondo , Sho Ishiwata , Shinichi Nakasuka , Tomoyasu Yamamuro

Optical interferometers provide multiple wavelength measurements. In order to fully exploit the spectral and spatial resolution of these instruments, new algorithms for image reconstruction have to be developed. Early attempts to deal with…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Éric Thiébaut , Ferréol Soulez , Loïc Denis

Next generation communication systems require accurate beam alignment to counteract the impairments that characterize propagation in high-frequency bands. The overhead of the pilot sequences required to select the best beam pair is…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Tien Ngoc Ha , Daniel Romero , Roberto López-Valcarce

Interferometers play an increasingly important role for spatially resolved observations. If employed at full potential, interferometry can probe an enormous dynamic range in spatial scale. Interpretation of the observed visibilities…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 C. Brinch , C. P. Dullemond

Reconfigurable intelligent surfaces (RISs) are one of the foremost technological enablers of future wireless systems. They improve communication and localization by providing a strong non-line-of-sight path to the receiver. In this paper,…

Signal Processing · Electrical Eng. & Systems 2022-04-26 Kamran Keykhosravi , Henk Wymeersch

Direction of arrival (DOA) estimation is mostly performed using specialized arrays that have carefully designed receiver spacing and layouts to match the operating frequency range. In contrast, radio interferometric arrays are designed to…

Instrumentation and Methods for Astrophysics · Physics 2025-12-23 Sarod Yatawatta

A class of methods for measuring time delays between astronomical time series is introduced in the context of quasar reverberation mapping, which is based on measures of randomness or complexity of the data. Several distinct statistical…

Instrumentation and Methods for Astrophysics · Physics 2017-08-16 Doron Chelouche , Francisco Pozo Nuñez , Shay Zucker

Motivated by future automotive applications, we study some joint radar target detection and parameter estimation problems where the transmitter, equipped with a mono-static MIMO radar, wishes to detect multiple targets and then estimate…

Signal Processing · Electrical Eng. & Systems 2020-09-21 Lorenzo Gaudio , Mari Kobayashi , Giuseppe Caire , Giulio Colavolpe

We present a new approach for image reconstruction and weak lensing measurements with interferometers. Based on the shapelet formalism presented in Refregier (2001), object images are decomposed into orthonormal Hermite basis functions. The…

Astrophysics · Physics 2009-11-06 Tzu-Ching Chang , Alexandre Refregier

Next generation radio telescopes, like the Square Kilometre Array, will acquire an unprecedented amount of data for radio astronomy. The development of fast, parallelisable or distributed algorithms for handling such large-scale data sets…

Instrumentation and Methods for Astrophysics · Physics 2016-10-28 Alexandru Onose , Rafael E. Carrillo , Jason D. McEwen , Yves Wiaux

We propose the combination of forward shape derivatives and the use of an iterative inversion scheme for Bayesian optimization to find optimal designs of nanophotonic devices. This approach widens the range of applicability of Bayesian…

Computational Physics · Physics 2021-01-12 Xavier Garcia-Santiago , Sven Burger , Carsten Rockstuhl , Philipp-Immanuel Schneider

Reconfigurable intelligent surfaces (RISs) are an emerging technology for improving spectral efficiency and reducing power consumption in future wireless systems. This paper investigates the joint design of the transmit precoding matrices…

Optimization and Control · Mathematics 2025-07-22 Shumin Wang , Hajar El Hassani , Marco Di Renzo , Marios Poulakis

Modern interferometric imaging relies on advanced calibration that incorporates direction-dependent effects. Their increasing number of antennas (e.g. in LOFAR, VLA, MeerKAT/SKA) and sensitivity are often tempered with the accuracy of their…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 K. Iheanetu , J. N. Girard , O. Smirnov , K. M. B. Asad , M. de Villiers , K. Thorat , S. Makhathini , R. A. Perley

The tilted-wave interferometer is a promising technique for the development of a reference measurement system for the highly accurate form measurement of aspheres and freeform surfaces. The technique combines interferometric measurements,…

We have developed an algorithm that constructs a model of a reconfigurable optical interferometer, independent of specific architectural constraints. The programming of unitary transformations on the interferometer's optical modes relies on…

Quantum Physics · Physics 2025-06-02 Sergei S. Kuzmin , Ivan V. Dyakonov , Stanislav S. Straupe

AI/ML-based beam selection methods coupled with location information effectively reduce beam training overhead. Unfortunately, heterogeneous antenna hardware with varying dimensions, orientations, codebooks, element patterns, and…

Signal Processing · Electrical Eng. & Systems 2026-02-24 Ibrahim Kilinc , Robert W. Heath

A radio interferometer uses time delays to maximize its response to radiation coming from a particular direction. These time delays compensate for differences in the time of arrival of the wavefront at the different elements of the…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 P. Salas , M. A. Brentjens , D. D. Bordenave , J. B. R. Oonk , H. J. A. Röttgering