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An enhanced multiple-edge response (MER) based eye diagram estimation method is proposed to evaluate the performance of nonlinear systems with input jitter. Compared with existing MER-based methods which only took into account the bit…

Signal Processing · Electrical Eng. & Systems 2023-12-18 Hanqing Zhang , Feijun Zheng

Mathematical models involving switches --- in the form of differential equations with discontinuities --- can accomodate real-world non-idealities through perturbations by hysteresis, time-delay, discretization, and noise. These are used to…

Dynamical Systems · Mathematics 2016-10-14 Mike R. Jeffrey , Georgios Kafanas , David J. W. Simpson

We introduce deep-field metacalibration, a new technique that reduces the pixel noise in metacalibration estimators of weak lensing shear signals by using a deeper imaging survey for calibration. In standard metacalibration, when estimating…

Instrumentation and Methods for Astrophysics · Physics 2023-05-19 Zhuoqi Zhang , Matthew R. Becker , Erin S. Sheldon

Characterization of the atmospheres of transiting exoplanets relies on accurate measurements of the extent of the optically thick area of the planet at multiple wavelengths with a precision $\lesssim$100 parts per million (ppm).…

Earth and Planetary Astrophysics · Physics 2017-09-06 Giuseppe Morello , Angelos Tsiaras , Ian D. Howarth , Derek Homeier

The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a hardware simulator for wavefront sensing and control designed to produce JWST-like images. A model of the JWST three mirror anas- tigmat is realized with three…

Linear Array Pushbroom (LAP) imaging technology is widely used in the realm of remote sensing. However, images acquired through LAP always suffer from distortion and blur because of camera jitter. Traditional methods for restoring LAP…

Computer Vision and Pattern Recognition · Computer Science 2024-01-17 Zida Chen , Ziran Zhang , Haoying Li , Menghao Li , Yueting Chen , Qi Li , Huajun Feng , Zhihai Xu , Shiqi Chen

Restoring images distorted by atmospheric turbulence is a ubiquitous problem in long-range imaging applications. While existing deep-learning-based methods have demonstrated promising results in specific testing conditions, they suffer from…

Image and Video Processing · Electrical Eng. & Systems 2023-12-12 Xingguang Zhang , Zhiyuan Mao , Nicholas Chimitt , Stanley H. Chan

A new generation of telescopes with mirror diameters of 20 m or more, called extremely large telescopes (ELTs) has the potential to provide unprecedented imaging and spectroscopy of exo-planetary systems, if the difficulties in achieving…

Instrumentation and Methods for Astrophysics · Physics 2016-04-20 Richard A. Frazin

Constraining the mass-sheet degeneracy (MSD) is crucial for improving the precision and accuracy of time-delay cosmography. Joint analyses of lensing and stellar kinematics are widely adopted to break the MSD. A 3D mass and stellar tracer…

Astrophysics of Galaxies · Physics 2025-11-19 Xiang-Yu Huang , Simon Birrer , Michele Cappellari , Tommaso Treu , Shawn Knabel , Dominique Sluse

We investigate the influence of random variations of the Galactic gravitational field on the apparent celestial positions of extragalactic sources. The basic statistical characteristics of a stochastic process (first-order moments, an…

Astrophysics of Galaxies · Physics 2017-02-03 T. Larchenkova , A. Lutovinov , N. Lyskova

In this paper, we introduce a system based on transfer learning for detecting segment misalignment in multimirror satellites, such as future CubeSat designs and the James Webb Space Telescope (JWST), using image-based methods. When a mirror…

Computer Vision and Pattern Recognition · Computer Science 2024-07-31 C. Tanner Fredieu , Jonathan Tesch , Andrew Kee , David Redding

Atmospheric Turbulence (AT) degrades the clarity and accuracy of surveillance imagery, posing challenges not only for visualization quality but also for object classification and scene tracking. Deep learning-based methods have been…

Computer Vision and Pattern Recognition · Computer Science 2025-11-25 Paul Hill , Zhiming Liu , Alin Achim , Dave Bull , Nantheera Anantrasirichai

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The…

General Relativity and Quantum Cosmology · Physics 2011-09-28 Thomas P. Kling , Louis Bianchini

Metacalibration is a state-of-the-art technique for measuring weak gravitational lensing shear from well-sampled galaxy images. We investigate the accuracy of shear measured with metacalibration from fitting elliptical Gaussians to…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Arun Kannawadi , Erik Rosenberg , Henk Hoekstra

Precise radial velocity (PRV) surveys are important for the search of Earth analogs around nearby bright stars. Such planets induce a small stellar reflex motion with RV amplitude of $\sim$10 cm/s. Detecting such a small RV signal poses…

Artificial Neural Network (ANN) is used as numerical methode in solving modified Nonlinear Schroedinger (NLS) equation with Dispersion Managed System (DMS) for jitter analysis. We take the optical axis z and the time t as input, and then…

Pattern Formation and Solitons · Physics 2007-05-23 F. P. Zen , B. E. Gunara , W. Hidayat , Z. A. Thalib , H. Zainuddin , J. Aminuddin

The coupling between far-field wavefront error (WFE) and laser pointing jitter is an important source of tilt-to-length (TTL) noise in spaceborne laser interferometric links. We extend the Nijboer--Zernike analytical model for far-field WFE…

Instrumentation and Methods for Astrophysics · Physics 2026-04-30 Ya-Zheng Tao , Rui-Hong Gao , Guangzhou Xu , Yue-Liang Wu

Atmospheric lidar observations provide a unique capability to directly observe the vertical column of cloud and aerosol scattering properties. Detector and solar background noise, however, hinder the ability of lidar systems to provide…

Optimization and Control · Mathematics 2016-06-21 Willem J. Marais , Robert E. Holz , Yu Hen Hu , Ralph E. Kuehn , Edwin E. Eloranta , Rebecca M. Willett

Diffusion models (DMs) embark a new era of generative modeling and offer more opportunities for efficient generating high-quality and realistic data samples. However, their widespread use has also brought forth new challenges in model…

Computer Vision and Pattern Recognition · Computer Science 2024-10-14 Jingyao Xu , Yuetong Lu , Yandong Li , Siyang Lu , Dongdong Wang , Xiang Wei

Differential Optical Transfer Function (dOTF) is an image-based, non-iterative wavefront sensing method that uses two star images with a single small change in the pupil. We describe two possible methods for introducing the required pupil…

Instrumentation and Methods for Astrophysics · Physics 2015-03-02 Johanan L. Codona , Nathan Doble
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