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Related papers: Characterising the Apertif primary beam response

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First-Person-View (FPV) holds immense potential for revolutionizing the trajectory of Unmanned Aerial Vehicles (UAVs), offering an exhilarating avenue for navigating complex building structures. Yet, traditional Neural Radiance Field (NeRF)…

Computer Vision and Pattern Recognition · Computer Science 2024-08-13 Liqi Yan , Qifan Wang , Junhan Zhao , Qiang Guan , Zheng Tang , Jianhui Zhang , Dongfang Liu

We investigate the focal plane wavefront sensing technique, known as Phase Diversity, at the scientific focal plane of a segmented mirror telescope with an adaptive optics (AO) system. We specifically consider an optical system imaging a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-03 Masen Lamb , Carlos Correia , Suresh Sivanandam , Robin Swanson , Polina Zavyalova

Multiple independent radio frequency (RF) beams find applications in communications, radio astronomy, radar, and microwave imaging. An $N$-point FFT applied spatially across an array of receiver antennas provides $N$-independent RF beams at…

Methodology · Statistics 2015-01-09 D. Suarez , R. J. Cintra , F. M. Bayer , A. Sengupta , S. Kulasekera , A. Madanayake

We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual…

Ground-based, high-resolution bolometric (sub)millimeter continuum mapping observations on spatially extended target sources are often subject to significant missing fluxes. This hampers accurate quantitative analyses. Missing flux can be…

Instrumentation and Methods for Astrophysics · Physics 2022-08-02 Sihan Jiao , Yuxin Lin , Xiangyu Shui , Jingwen Wu , Zhiyuan Ren , Di Li

We propose a novel integrated sensing and communication (ISAC) system that leverages sensing to assist communication, ensuring fast initial access, seamless user tracking, and uninterrupted communication for millimeter wave (mmWave)…

Signal Processing · Electrical Eng. & Systems 2024-03-15 Gui Zhou , Moritz Garkisch , Zhendong Peng , Cunhua Pan , Robert Schober

We present a deterministic framework for three-dimensional beam shaping that enables versatile control of intensity and phase, pixel-by-pixel, across multiple axial planes. Conventional multi-plane holographic techniques typically rely on…

Interferometry can measure the shape or the material density of a system that could not be measured otherwise by recording the difference between the phase change of a signal and a reference phase. This difference is always between $-\pi$…

Plasma Physics · Physics 2022-10-20 Pierre-Alexandre Gourdain , Aidan Bachmann

Variations of the antenna primary beam (PB) pattern as a function of time, frequency and polarization form one of the dominant direction-dependent effects at most radio frequency bands. These gains may also vary from antenna to antenna. The…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 S. Bhatnagar , U. Rau , K. Golap

We investigate the 1/f noise of the Five-hundred-meter Aperture Spherical Telescope (FAST) receiver system using drift-scan data from an intensity mapping pilot survey. All the 19 beams have 1/f fluctuations with similar structures. Both…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Wenkai Hu , Yichao Li , Yougang Wang , Fengquan Wu , Bo Zhang , Ming Zhu , Shifan Zuo , Guilaine Lagache , Yinzhe Ma , Mario G. Santos , Xuelei Chen

We explore the morphological properties of symmetric Airy beams in the paraxial and nonparaxial regimes. We consider a 2D electromagnetic realization with a single transverse component of the electric field, and in the nonparaxial regime,…

Optics · Physics 2019-07-25 F. Camas-Aquino , P. A. Quinto-Su , R. Jáuregui

We describe a theoretical procedure for analyzing astronomical phased arrays with overlapping beams, and apply the procedure to simulate a simple example. We demonstrate the effect of overlapping beams on the number of degrees of freedom of…

Astrophysics · Physics 2009-11-13 George Saklatvala , Stafford Withington , Michael P. Hobson

Infrared and visible image fusion(IVIF) combines complementary modalities while preserving natural textures and salient thermal signatures. Existing solutions predominantly rely on extensive sets of rigidly aligned image pairs for training.…

Computer Vision and Pattern Recognition · Computer Science 2026-03-24 Yanglin Deng , Tianyang Xu , Chunyang Cheng , Hui Li , Xiao-jun Wu , Josef Kittler

Atmospheric turbulence and precise measurement of the astrometric baseline vector between any two telescopes are two major challenges in implementing phase referenced interferometric astrometry and imaging. They limit the performance of a…

Instrumentation and Methods for Astrophysics · Physics 2018-03-14 N. Anugu , A. Amorim , P. Gordo , F. Eisenhauer , O. Pfuhl , M. Haug , E. Wiezorrek , J. Lima , G. Perrin , W. Brandner , C. Straubmeier , J. -B. Le Bouquin , P. J. V Garcia

We describe a fast and accurate method to perform the convolution of a sky map with a general asymmetric main beam along any given scanning strategy. The method is based on the decomposition of the beam as a sum of circular functions, here…

Astrophysics · Physics 2009-11-10 M. Tristram , J. -C. Hamilton , J. F. Macias-Perez , C. Renault

The final performance of current and future instruments dedicated to exoplanet detection and characterization (such as SPHERE on the European Very Large Telescope, GPI on Gemini North, or future instruments on Extremely Large Telescopes) is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 B. Paul , L. M. Mugnier , J. -F. Sauvage

Brown dwarfs in close-in orbits around white dwarfs offer an excellent opportunity to investigate properties of fast-rotating, tidally-locked, and highly-irradiated atmospheres. We present Hubble Space Telescope Wide Field Camera 3 G141…

Angle-resolved (AR) RABBIT measurements offer a high information content measurement scheme, due to the presence of multiple, interfering, ionization channels combined with a phase-sensitive observable in the form of angle and time-resolved…

Quantum Physics · Physics 2017-09-05 Paul Hockett

Overlapping object perception aims to decouple the randomly overlapping foreground-background features, extracting foreground features while suppressing background features, which holds significant application value in fields such as…

Computer Vision and Pattern Recognition · Computer Science 2025-06-17 Mingyuan Li , Tong Jia , Han Gu , Hui Lu , Hao Wang , Bowen Ma , Shuyang Lin , Shiyi Guo , Shizhuo Deng , Dongyue Chen

Localization of a radio frequency (RF) transmitter with intermittent transmissions is considered via a group of unmanned aerial vehicles (UAVs) equipped with omnidirectional received signal strength (RSS) sensors. This group embarks on an…

Signal Processing · Electrical Eng. & Systems 2018-01-09 Farshad Koohifar , Ismail Guvenc , Mihail L. Sichitiu
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