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Full Waveform Inversion (FWI) stands as a nonlinear, high-resolution technology for subsurface imaging via surface-recorded data. This paper introduces an augmented Lagrangian dual formulation for FWI, rooted in the viewpoint that Lagrange…

Geophysics · Physics 2024-12-13 Kamal Aghazade , Ali Gholami

Terahertz (THz) integrated sensing and communication (ISAC) is a promising interdisciplinary technology that realizes simultaneously transmitting Terabit-per-second (Tbps) and millimeter-level accurate environment or human activity sensing.…

Signal Processing · Electrical Eng. & Systems 2023-02-28 Yongzhi Wu , Chong Han , Zhi Chen

Radio imaging is rapidly gaining prominence in the design of future communication systems, with the potential to utilize reconfigurable intelligent surfaces (RISs) as imaging apertures. Although the sparsity of targets in three-dimensional…

Information Theory · Computer Science 2024-04-09 Yixuan Huang , Jie Yang , Wankai Tang , Chao-Kai Wen , Shi Jin

Full waveform inversion (FWI) is able to construct high-resolution subsurface models by iteratively minimizing discrepancies between observed and simulated seismic data. However, its implementation can be rather involved for complex wave…

Machine Learning · Computer Science 2025-06-24 Feng Liu , Haipeng Li , Guangyuan Zou , Junlun Li

Fluid antenna systems encompass a broad class of reconfigurable antenna technologies that offer substantial spatial diversity for various optimization objectives and communication tasks. Their capability to enhance spatial resolution within…

Information Theory · Computer Science 2025-12-01 Jingyuan Xu , Zhentian Zhang , Jian Dang , Hao Jiang , Zaichen Zhang

This work presents a purely data-driven, wavelet-based framework for modal identification and reduced-order modeling of mechanical systems with assumed linear dynamics characterized by closely spaced modes with classical or non-classical…

Signal Processing · Electrical Eng. & Systems 2025-10-28 Anargyros Michaloliakos , Benjamin J. Chang , Lawrence A. Bergman , Alexander F. Vakakis

The Multiconjugate Adaptive optics Demonstrator (MAD) has successfully demonstrated on sky both Star Oriented (SO) and Layer Oriented (LO) multiconjugate adaptive optics techniques. While SO has been realized using 3 Shack-Hartmann…

Recently, a two-dimension (2D) modulation waveform of orthogonal time-frequency-space (OTFS) has been a popular 6G candidate to replace existing orthogonal frequency division multiplexing (OFDM). The extensive OTFS researches help to make…

Signal Processing · Electrical Eng. & Systems 2024-12-30 Yihua Ma , Zhifeng Yuan , Yu Xin , Jiang Hua , Guanghui Yu , Jin Xu , Liujun Hu

The advent of spatiotemporal wave packets (STWPs), represented by spatiotemporal optical vortices (STOVs), has paved the way for the exploration in optics and photonics. To date, despite considerable efforts, a comprehensive and efficient…

This comprehensive review paper delves into the intricacies of advanced Fourier type integral transforms and their mathematical properties, with a particular focus on fractional Fourier transform (FrFT), linear canonical transform (LCT),…

Classical Analysis and ODEs · Mathematics 2024-02-13 Bivek Gupta , Amit K. Verma

Shack-Hartmann wavefront sensors (SHWS) are generally used to measure the wavefront curvature of light beams. Measurement accuracy and the sensitivity of these sensors are important factors for better wavefront sensing. In this study, we…

Optics · Physics 2021-10-04 Nitin Dubey , Ravi Kumar , Joseph Rosen

The calibration of future wide field adaptive optics (WFAO) systems requires knowledge of the geometry of the system, in particular the alignment parameters between the sub-apertures of the wavefront sensors (WFS), pupil and deformable…

Instrumentation and Methods for Astrophysics · Physics 2025-07-02 Guido Agapito , Cédric Plantet , Cédric Taïssir Heritier

For astronomical instruments, accurate knowledge of the optical pointing and coupling are essential to characterize the alignment and performance of (sub-)systems prior to integration and deployment. Ideally, this requires the phase…

Instrumentation and Methods for Astrophysics · Physics 2020-02-11 S. J. C. Yates , K. K. Davis , W. Jellema , J. J. A. Baselmans , A. M. Baryshev

Vast tunable optical components are realized based on dynamic reconfigurations of the incident wavefronts, such as beam steering and tunable lens. However, the dominant paradigm of current wavefront reconfiguration technologies relies on…

Optics · Physics 2022-01-27 Wenjun Deng , Weiming Zhu , Yuzhi Shi , Zhijun Liu , Guanxing Zang , Jin Qin , Shiyu Zhu

Full waveform inversion (FWI) is an iterative identification process that serves to minimize the misfit of model-based simulated and experimentally measured wave field data, with the goal of identifying a field of parameters for a given…

Computational Engineering, Finance, and Science · Computer Science 2023-12-05 Tim Bürchner , Philipp Kopp , Stefan Kollmannsberger , Ernst Rank

High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

We present a novel three-dimensional (3D) imaging approach that combines two-dimensional spatial Fourier-domain imaging techniques with traditional radar pulse compression to recover both cross-range and down-range scene information. The…

Signal Processing · Electrical Eng. & Systems 2025-07-11 Jorge R. Colon-Berrios , Jason M. Merlo , Jeffrey A. Nanzer

In this paper, we introduce a new 2D modulation scheme referred to as OTFS (Orthogonal Time Frequency & Space) that multiplexes information QAM symbols over new class of carrier waveforms that correspond to localized pulses in a signal…

Information Theory · Computer Science 2018-02-09 Ronny Hadani , Anton Monk

In this paper, we describe the principle of a multi-aperture interferometer that uses a phase-shifting technique and is suitable for quick, snapshot imaging of astrophysical objects at extreme angular resolution through Fourier inversion. A…

Optics · Physics 2015-05-28 Francois Henault

Almost all current and future high-contrast imaging instruments will use a Pyramid wavefront sensor (PWFS) as a primary or secondary wavefront sensor. The main issue with the PWFS is its nonlinear response to large phase aberrations,…