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Related papers: Reduced Ambiguity Calibration for LOFAR

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Sensor calibration is the fundamental block for a multi-sensor fusion system. This paper presents an accurate and repeatable LiDAR-IMU calibration method (termed LI-Calib), to calibrate the 6-DOF extrinsic transformation between the 3D…

Robotics · Computer Science 2020-07-30 Jiajun Lv , Jinhong Xu , Kewei Hu , Yong Liu , Xingxing Zuo

Due to the large dynamic ranges involved with separating the cosmological 21-cm signal from the Cosmic Dawn from galactic foregrounds, a well-calibrated instrument is essential to avoid biases from instrumental systematics. In this paper we…

A method is described that allows calibration and assessment of the linearity of response of an array of photomultiplier tubes. The method does not require knowledge of the photomultiplier single photoelectron response model and uses…

The correction of the influence of phase corrugation in the pupil plane is a fundamental issue in achieving high dynamic range imaging. In this paper, we investigate an instrumental setup which consists in applying interferometric…

Astrophysics · Physics 2008-11-26 S. Lacour , E. Thiébaut , G. Perrin

Flux calibration of spectra in reverberation mapping (RM) is most often performed by assuming the flux constancy of some specified narrow emission lines, which stem from an extended region that is sometimes partially spatially resolved, in…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Yan-Rong Li , Jian-Min Wang , Chen Hu , Pu Du , Jin-Ming Bai

In a companion paper, we presented BayesCal, a mathematical formalism for mitigating sky-model incompleteness in interferometric calibration. In this paper, we demonstrate the use of BayesCal to calibrate the degenerate gain parameters of…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Peter H. Sims , Jonathan C. Pober , Jonathan L. Sievers

The two output signals of quadrature phase interferometers allow to benefit both from the high sensitivity of interferometry (working inside a fringe) and from an extended input range (counting fringes). Their calibration to reach a linear…

Instrumentation and Detectors · Physics 2022-09-07 Baptiste Ferrero , Ludovic Bellon

The choice of poses for camera calibration with planar patterns is only rarely considered - yet the calibration precision heavily depends on it. This work presents a pose selection method that finds a compact and robust set of calibration…

Computer Vision and Pattern Recognition · Computer Science 2019-07-15 Pavel Rojtberg , Arjan Kuijper

Fourier ptychography captures intensity images with varying source patterns (illumination angles) in order to computationally reconstruct large space-bandwidth-product images. Accurate knowledge of the illumination angles is necessary for…

Signal Processing · Electrical Eng. & Systems 2018-11-01 Regina Eckert , Zachary F. Phillips , Laura Waller

In this paper we present a novel algorithm for onboard radial distortion correction for unmanned aerial vehicles (UAVs) equipped with an inertial measurement unit (IMU), that runs in real-time. This approach makes calibration procedures…

Computer Vision and Pattern Recognition · Computer Science 2021-03-18 Marcus Valtonen Örnhag , Patrik Persson , Mårten Wadenbäck , Kalle Åström , Anders Heyden

One of the biggest challenges in operating massive multiple-input multiple-output systems is the acquisition of accurate channel state information at the transmitter. To take up this challenge, time division duplex is more favorable thanks…

Information Theory · Computer Science 2024-10-30 Xiwen Jiang , Alexis Decurninge , Kalyana Gopala , Florian Kaltenberger , Maxime Guillaud , Dirk Slock , Luc Deneire

The integrated inertial system, typically integrating an IMU and an exteroceptive sensor such as radar, LiDAR, and camera, has been widely accepted and applied in modern robotic applications for ego-motion estimation, motion control, or…

Robotics · Computer Science 2024-11-15 Shuolong Chen , Xingxing Li , Shengyu Li , Yuxuan Zhou , Xiaoteng Yang

We present a filtering technique that can be applied to individual baselines of wide-bandwidth, wide-field interferometric data to geometrically select regions on the celestial sphere that contain primary calibration sources. The technique…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Aaron R. Parsons , Donald C. Backer

The radio astronomy community is currently building a number of phased array telescopes. The calibration of these telescopes is hampered by the fact that covariances of signals from closely spaced antennas are sensitive to noise coupling…

Instrumentation and Methods for Astrophysics · Physics 2010-03-15 Stefan J. Wijnholds , Alle-Jan van der Veen

This chapter aims to provide a review of the basics of 21 cm interferometric observations and its methodologies. A summary of the main concepts of radio interferometry and their connection with the 21 cm observables - power spectra and…

Instrumentation and Methods for Astrophysics · Physics 2019-09-27 G. Bernardi

Recovering images from optical interferometric observations is one of the major challenges in the field. Unlike the case of observations at radio wavelengths, in the optical the atmospheric turbulence changes the phases on a very short time…

Camera calibration is a crucial step in photogrammetry and 3D vision applications. This paper introduces a novel camera calibration method using a designed collimator system. Our collimator system provides a reliable and controllable…

Computer Vision and Pattern Recognition · Computer Science 2025-12-19 Shunkun Liang , Banglei Guan , Zhenbao Yu , Dongcai Tan , Pengju Sun , Zibin Liu , Qifeng Yu , Yang Shang

Many astronomical questions require deep, wide-field observations at low radio frequencies. Phased arrays like LOFAR and SKA-low are designed for this, but have inherently unstable element gains, leading to time, frequency and…

Instrumentation and Methods for Astrophysics · Physics 2025-08-28 S. A. Brackenhoff , A. R. Offringa , M. Mevius , L. V. E. Koopmans , J. K. Chege , E. Ceccotti , C. Höfer , L. Gao , S. Ghosh , F. G. Mertens , S. Munshi

One of the biggest challenges associated with a nulling interferometer-based approach to detecting extra-solar Earth-like planets comes from the extremely stringent requirements of pathlength, polarization and amplitude matching in the…

Astrophysics · Physics 2008-11-26 Benjamin F. Lane , Matthew W. Muterspaugh , Michael Shao

Obtaining reliable and accurate quantification of uncertainty estimates from deep neural networks is important in safety-critical applications. A well-calibrated model should be accurate when it is certain about its prediction and indicate…

Machine Learning · Computer Science 2020-12-16 Ranganath Krishnan , Omesh Tickoo
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