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The Graphics Processing Unit (GPU) has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Jayanth Chennamangalam , Simon Scott , Glenn Jones , Hong Chen , John Ford , Amanda Kepley , D. R. Lorimer , Jun Nie , Richard Prestage , D. Anish Roshi , Mark Wagner , Dan Werthimer

Multimode fibers have been proposed for mitigating nonlinear effects in high-power fiber amplifiers, allowing for significant power scaling. Most previous studies on light propagation in continuous-wave fiber amplifiers focus on single mode…

Conventional spectrometer and polarimeter systems rely on bulky optics, fundamentally limiting compact integration and hindering multi-dimensional optical sensing capabilities. Here, we propose a spectropolarimeter enabled by…

Optics · Physics 2026-04-13 Jumin Qiu , Tingting Liu , Chenxuan Xiang , Tianbao Yu , Qiegen Liu , Shuyuan Xiao

A new multi-frequency synthesis algorithm for reconstructing images from multi-frequency VLBI data is proposed. The algorithm is based on a generalized maximum-entropy method, and makes it possible to derive an effective spectral correction…

Astrophysics · Physics 2011-08-31 Anisa T. Bajkova

This paper proposes a novel feature called spectrum congruency for describing edges in images. The spectrum congruency is a generalization of the phase congruency, which depicts how much each Fourier components of the image are congruent in…

Image and Video Processing · Electrical Eng. & Systems 2021-03-11 Fang Yang , Xin Su , Li Chai

There are several high-performance adaptive optics systems that deliver diffraction-limited imaging on ground-based telescopes, which renewed the interest of single-mode fiber (SMF) spectroscopy for exoplanet characterization. However, the…

Instrumentation and Methods for Astrophysics · Physics 2021-05-19 S. Y. Haffert

We put forward a method that allows the experimental determination of the entire spatial mode spectrum of any arbitrary monochromatic wave field in a plane normal to its propagation direction. For coherent optical fields, our spatial…

Quantum Physics · Physics 2011-02-08 Gabriel F. Calvo , Antonio Picón , Roberta Zambrini

In astronomical spectroscopy, optical fibres are abundantly used for multiplexing and decoupling the spectrograph from the telescope to provide stability in a controlled environment. However, fibres are less than perfect optical components…

Instrumentation and Methods for Astrophysics · Physics 2021-05-05 E. Hernandez , M. M. Roth , K. Petermann , A. Kelz , B. Moralejo , K. Madhav

Optical fibres are the primary medium for optical signal transmission, and their guided modes provide a high-dimensional basis for modal-domain information encoding. However, conventional demultiplexing approaches typically convert fibre…

Optics · Physics 2026-05-29 Rundong Fan , Yamin Zheng , Pei Li , Xixiao Cao , Haoyang Wu , Zheng Cai , Lei Huang

Correlation radiometers make true differential measurements in power with high accuracy and small systematic errors. This receiver architecture has been used in radio astronomy for measurements of continuum radiation for over 50 years; this…

Astrophysics · Physics 2007-05-23 A. I. Harris

Hybrid beamforming (HBF) is an attractive technology for practical massive multiple-input and multiple-output (MIMO) millimeter wave (mmWave) systems. Compared with the fully-connected HBF architecture, the partially-connected one can…

Information Theory · Computer Science 2020-10-12 Xingyu Zhao , Tian Lin , Yu Zhu , Jun Zhang

Existing super-resolution methods of optical imaging hold a solid place as an application in natural sciences, but many new developments allow for beating the diffraction limit in a more subtle way. One of the recently explored strategies…

Quantum Physics · Physics 2022-02-08 Mateusz Mazelanik , Adam Leszczyński , Michał Parniak

Optical fibers have altered astronomical instrument design by allowing for a complex, often large instrument to be mounted in a remote and stable location with respect to the telescope. The fibers also enable the possibility to rearrange…

Instrumentation and Methods for Astrophysics · Physics 2020-04-02 Nemanja Jovanovic , Robert J. Harris , Nick Cvetojevic

The development of deep neural networks is witnessing fast growth in network size, which requires novel hardware computing platforms with large bandwidth and low energy consumption. Optical computing has been a potential candidate for…

We radically simplify coherently averaged dual-comb spectroscopy by introducing a real-time self-correction system: a radio frequency system-on-chip computes each incoming dual-comb interferogram's phase, frequency, and arrival time;…

We present a new approach to multi-frequency synthesis in radio astronomy. Using Bayesian inference techniques, the new technique estimates the sky brightness and the spectral index simultaneously. In principle, the bandwidth of a wide-band…

Instrumentation and Methods for Astrophysics · Physics 2015-09-16 H. Junklewitz , M. A. Bell , T. Enßlin

Dispersion studies are conducted on 1m long multimode polymer spiral waveguides with different refractive index profiles. Bandwidth-length products >40GHzxm are obtained from such waveguides under a 50/125 um MMF, indicating the potential…

Instrumentation and Detectors · Physics 2017-02-03 Jian Chen , Nikos Bamiedakis , Tom J. Edwards , Christian T. A. Brown , Richard V. Penty , Ian H. White

Integrating conventional optics into compact nanostructured surfaces is the goal of flat optics. Despite the enormous progress of this technology, there are still critical challenges for real world applications due to a limited efficiency…

Frequency comb spectroscopy provides broadband access to molecular fingerprints with mode-defined spectral resolution. However, its deployment in non-cooperative gas sensing remains challenging because conventional implementations require…

Mode mixing in optical fibers caused by mechanical bending induces perturbations that distort the spatial field profile of coherent beams as they propagate through few-mode or multimode fibers. The observed output from a bent fiber commonly…

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