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Radars provide robust perception of vehicle surroundings by effectively functioning in poor light and adverse weather conditions. Synthetic aperture radar (SAR) algorithms are employed to address the limited angular resolution of radars by…

Signal Processing · Electrical Eng. & Systems 2026-03-10 S. Hamed Javadi , André Bourdoux , Adnan Albaba , Hichem Sahli

Recent developments in Carrillo et al. (2012) and Carrillo et al. (2013) introduced a novel regularization method for compressive imaging in the context of compressed sensing with coherent redundant dictionaries. The approach relies on the…

Information Theory · Computer Science 2013-07-05 Rafael E. Carrillo , Jason D. McEwen , Yves Wiaux

This study presents an effective autofocusing approach for synthetic aperture radar imaging of the human body under conditions of respiratory motion. The proposed method suppresses respiratory-motion-induced phase errors by separating radar…

Signal Processing · Electrical Eng. & Systems 2026-01-13 Masaya Kato , Takuya Sakamoto

Many imaging problems require solving an inverse problem that is ill-conditioned or ill-posed. Imaging methods typically address this difficulty by regularising the estimation problem to make it well-posed. This often requires setting the…

Methodology · Statistics 2020-08-17 Ana F. Vidal , Valentin De Bortoli , Marcelo Pereyra , Alain Durmus

Synthetic aperture radar (SAR) images are often blurred by phase perturbations induced by uncompensated sensor motion and /or unknown propagation effects caused by turbulent media. To get refocused images, autofocus proves to be useful…

Instrumentation and Methods for Astrophysics · Physics 2015-03-03 Xinhua Mao , Daiyin Zhu , Zhaoda Zhu

In complex-valued coherent inverse problems such as synthetic aperture radar (SAR), one may often have prior information only on the magnitude image which shows the features of interest such as strength of reflectivity. In contrast, there…

Numerical Analysis · Mathematics 2024-10-30 F. M. Watson , W. R. B. Lionheart , J. Hellier

We present an adaptive regularization scheme for optimizing composite energy functionals arising in image analysis problems. The scheme automatically trades off data fidelity and regularization depending on the current data fit during the…

Computer Vision and Pattern Recognition · Computer Science 2017-05-10 Byung-Woo Hong , Ja-Keoung Koo , Martin Burger , Stefano Soatto

Image segmentation techniques are predominately based on parameter-laden optimization. The objective function typically involves weights for balancing competing image fidelity and segmentation regularization cost terms. Setting these…

Computer Vision and Pattern Recognition · Computer Science 2009-06-24 Josna Rao , Ghassan Hamarneh , Rafeef Abugharbieh

Sharpness-Aware Minimization (SAM) has proven highly effective in improving model generalization in machine learning tasks. However, SAM employs a fixed hyperparameter associated with the regularization to characterize the sharpness of the…

Machine Learning · Computer Science 2024-12-24 Jinping Zou , Xiaoge Deng , Tao Sun

Images of near-field SAR contains spatial-variant sidelobes and clutter, subduing the image quality. Current image restoration methods are only suitable for small observation angle, due to their assumption of 2D spatial-invariant…

Signal Processing · Electrical Eng. & Systems 2022-10-06 Wensi Zhang , Xiaoling Zhang , Xu Zhan , Yuetonghui Xu , Jun Shi , Shunjun Wei

Image segmentation is an inherently ill-posed problem and thus requires regularization in order to limit the search space to reasonable solutions. A majority of segmentation methods integrates these regularization terms in one way or the…

Numerical Analysis · Mathematics 2018-10-31 Uri Nahum , Philippe C. Cattin

Optimization on Riemannian manifolds widely arises in eigenvalue computation, density functional theory, Bose-Einstein condensates, low rank nearest correlation, image registration, and signal processing, etc. We propose an adaptive…

Optimization and Control · Mathematics 2017-08-08 Jiang Hu , Andre Milzarek , Zaiwen Wen , Yaxiang Yuan

We introduce a novel regularization scheme: Systematic Analytic Regularization (SAR). SAR regularizes a theory at the level of the action by analytically continuing the power of the kinetic operator, ensuring that the theory is formally…

High Energy Physics - Theory · Physics 2026-04-20 Jarryd Bath , W. A. Horowitz

The reconstructed images from the Synthetic Aperture Radar (SAR) data suffer from multiplicative noise as well as low contrast level. These two factors impact the quality of the SAR images significantly and prevent any attempt to extract…

Image and Video Processing · Electrical Eng. & Systems 2024-12-05 Shahrokh Hamidi

Deep learning has demonstrated its power in image rectification by leveraging the representation capacity of deep neural networks via supervised training based on a large-scale synthetic dataset. However, the model may overfit the synthetic…

Computer Vision and Pattern Recognition · Computer Science 2021-06-21 Jinlong Fan , Jing Zhang , Dacheng Tao

Conventional Synthetic Aperture Radar (SAR) systems are limited in their ability to satisfy the increasing requirement for improved spatial resolution and wider coverage. The demand for high resolution requires high sampling rates, while…

Information Theory · Computer Science 2017-11-22 Kfir Aberman , Yonina C. Eldar

This work is concerned with applying iterative image reconstruction, based on constrained total-variation minimization, to low-intensity X-ray CT systems that have a high sampling rate. Such systems pose a challenge for iterative image…

Medical Physics · Physics 2016-11-17 Emil Y. Sidky , Rick Chartrand , Yuval Duchin , Christer Ullberg , Xiaochuan Pan

Benefiting from a relatively larger aperture's angle, and in combination with a wide transmitting bandwidth, near-field synthetic aperture radar (SAR) provides a high-resolution image of a target's scattering distribution-hot spots.…

Image and Video Processing · Electrical Eng. & Systems 2022-11-29 Xu Zhan , Xiaoling Zhang , Wensi Zhang , Jun Shi , Shunjun Wei , Tianjiao Zeng

Remote sensing visual question answering (RSVQA) has been involved in several research in recent years, leading to an increase in new methods. RSVQA automatically extracts information from satellite images, so far only optical, and a…

Computer Vision and Pattern Recognition · Computer Science 2024-08-29 Lucrezia Tosato , Sylvain Lobry , Flora Weissgerber , Laurent Wendling

The sparse-driven radar imaging can obtain the high-resolution images about target scene with the down-sampled data. However, the huge computational complexity of the classical sparse recovery method for the particular situation seriously…

Quantum Physics · Physics 2022-01-05 Xiaowen Liu , Chen Dong , Ying Luo , Le Kang , Yong Liu , Qun Zhang