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Related papers: The Fast Fourier Transform Telescope

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One of the main challenges for future 21 cm observations is to remove foregrounds which are several orders of magnitude more intense than the HI signal. We propose a new technique for removing foregrounds of the redshifted 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jungyeon Cho , A. Lazarian , P. Timbie

The standing waves existed in radio telescope data are primarily due to reflections among the instruments, which significantly impact the spectrum quality of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Eliminating…

Instrumentation and Methods for Astrophysics · Physics 2025-01-09 Chen Xu , Jie Wang , Yingjie Jing , Fujia Li , Hengqian Gan , Ziming Liu , Tiantian Liang , Qingze Chen , Zerui Liu , Zhipeng Hou , Hao Hu , Huijie Hu , Shijie Huang , Peng Jiang , Chuan-Peng Zhang , Yan Zhu

The use of Fourier methods in wave-front reconstruction can significantly reduce the computation time for large telescopes with a high number of degrees of freedom. However, Fourier algorithms for discrete data require a rectangular data…

Instrumentation and Methods for Astrophysics · Physics 2017-06-07 Charlotte Z. Bond , Carlos M. Correia , Jean-François Sauvage , Benoit Neichel , Thierry Fusco

Sonography techniques use multiple transducer elements for tissue visualization. Signals detected at each element are sampled prior to digital beamforming. The sampling rates required to perform high resolution digital beamforming are…

Information Theory · Computer Science 2013-07-25 Tanya Chernyakova , Yonina C. Eldar

Diffraction tomography aims to recover an object's scattering potential from measured wave fields. In the classical setting, the object is illuminated by plane waves from many directions, and the Fourier diffraction theorem provides a…

Numerical Analysis · Mathematics 2026-03-11 Peter Elbau , Noemi Naujoks

Fourier ptychography (FP) is a promising computational imaging technique that overcomes the physical space-bandwidth product (SBP) limit of a conventional microscope by applying angular diversity illuminations. However, to date, the…

Optics · Physics 2018-10-17 An Pan , Yan Zhang , Kai Wen , Maosen Li , Meiling Zhou , Junwei Min , Ming Lei , Baoli Yao

Fourier transform spectroscopy (FTS) has been widely used in a variety of fields in research, industry, and medicine due to its high signal-to-noise ratio, simultaneous acquisition of signals in a broad spectrum, and versatility for…

Single-pixel imaging, with the advantages of a wide spectrum, beyond-visual-field imaging, and robustness to light scattering, has attracted increasing attention in recent years. Fourier single-pixel imaging (FSI) can reconstruct sharp…

Image and Video Processing · Electrical Eng. & Systems 2021-08-05 Dong Zhou , Jie Cao , Huan Cui , Qun Hao , Bing-Kun Chen , Kai Lin

Fourier-transform infrared spectroscopy (FTIR) has matured into a versatile technique with relevance for environmental monitoring, pharmaceutical research, and food safety applications. However, compared to other spectroscopic methods, it…

Instrumentation and Detectors · Physics 2024-09-04 Jakub Mnich , Johannes Kunsch , Matthias Budden , Thomas Gebert , Marco Schossig , Jarosław Sotor , Łukasz A. Sterczewski

This paper is the third part of a trilogy dealing with the principles, performance and limitations of what I named "Telescope-Interferometers" (TIs). The basic idea consists in transforming one telescope into a Wavefront Error (WFE) sensing…

Optics · Physics 2011-05-17 Francois Henault

The sky-averaged, or global, background of redshifted $21$ cm radiation is expected to be a rich source of information on cosmological reheating and reionizaton. However, measuring the signal is technically challenging: one must extract a…

Instrumentation and Methods for Astrophysics · Physics 2016-08-03 Tejaswi Venumadhav , Tzu-Ching Chang , Olivier Doré , Christopher M. Hirata

Optical frequency-comb-based-high-resolution spectrometers offer enormous potential for spectroscopic applications. Although various implementations have been demonstrated, the lack of suitable mid-infrared comb sources has impeded…

Millimeter wave communications require multibeam beamforming in order to utilize wireless channels that suffer from obstructions, path loss, and multi-path effects. Digital multibeam beamforming has maximum degrees of freedom compared to…

The Fractional Fourier Transform (FRT) corresponds to an arbitrary-angle rotation in the phase space, e.g. the time-frequency (TF) space, and generalizes the fundamentally important Fourier Transform. FRT applications range from classical…

Optics · Physics 2024-03-06 Michał Lipka , Michał Parniak

Laser guide stars with adaptive optics allow astronomical image correction in the absence of a natural guide star. Single guide star systems with a star created in the earth's sodium layer can be used to correct the wavefront in the near…

Astrophysics · Physics 2009-11-11 S. Rabien , F. Eisenhauer , R. Genzel , R. I. Davies , T. Ott

Historically employed spectroscopic architectures used for large field of view mapping spectroscopy in millimetere and sub-millimetre astronomy suffer from significant drawbacks. On-chip filterbank spectrometers are a promising technology…

Instrumentation and Methods for Astrophysics · Physics 2026-04-14 Chris S. Benson , Peter S. Barry , Patrick Ashworth , Harry Gordon-Moys , Kirit S. Karkare , Izaak Morris , Gethin Robson

Faraday tomography is a new method of the study of cosmic magnetic fields enabled by broadband low-frequency radio observations. By Faraday tomography, it is possible to obtain the Faraday dispersion function which contains information on…

Astrophysics of Galaxies · Physics 2023-03-15 Keitaro Takahashi

This paper presents the CosmicWeb-21cm array, a novel radio interferometer designed to overcome the key challenges in 21 cm cosmology. Its core innovations include: (1) a multi-scale nested geometry combining a hexagonal core with…

Instrumentation and Methods for Astrophysics · Physics 2026-03-03 Jiancheng Wang , Jirong Mao , Xiangming Cheng , Yigong Zhang , Jie Su , Xiaogu Zhong , Min Wang , Zhigang Zhang , Qingwei Wang , Yonghua Xu , Zhixuan Li , Longhua Qin , Zhengjun Zhang

We are developing the super broad band interferometer by applying the Fourier Transform Spectrometer(FTS) to aperture synthesis system in mm and sub-mm bands. We have constructed a compact system based on the Martin and Puplett type Fourier…

Astrophysics · Physics 2009-11-10 Izumi S. Ohta , Makoto Hattori , Hiroshi Matsuo

Having achieved 'first-light' right before the opening ceremony on September 25, 2016, the Five-hundred-meter Aperture Spherical radio Telescope (FAST) is being busily commissioned. Its innovative design requires ~1000 points to be measured…

Instrumentation and Methods for Astrophysics · Physics 2018-05-09 Di Li , Pei Wang , Lei Qian , Marko Krco , Alex Dunning , Peng Jiang , Youling Yue , Chenjin Jin , Yan Zhu , Zhichen Pan , Rendong Nan