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Affine frequency division multiplexing (AFDM) is a promising chirp-based waveform with high flexibility and resilience, making it well-suited for next-generation wireless networks, particularly in high-mobility scenarios. In this paper, we…

Signal Processing · Electrical Eng. & Systems 2025-07-14 Haoran Yin , Yanqun Tang , Yuanhan Ni , Zulin Wang , Gaojie Chen , Jun Xiong , Kai Yang , Marios Kountouris , Yong Liang Guan , Yong Zeng

Nearest neighbor (NN) graph based visual re-ranking has emerged as a powerful approach for improving retrieval accuracy, offering the advantages of effectively exploring high-dimensional manifolds without requiring additional fine-tuning.…

Computer Vision and Pattern Recognition · Computer Science 2025-07-09 Jaeyoon Kim , Yoonki Cho , Taeyoung Kim , Sung-Eui Yoon

Context: Fourier transform (or lag) correlators in radio interferometers can serve as an efficient means of synthesising spectral channels. However aliasing corrupts the edge channels so they usually have to be excluded from the data set.…

Astrophysics · Physics 2009-11-13 Tak Kaneko , Keith Grainge

Radar targets are traditionally modelled as point target reflectors, even in the near-field region. Yet, for radar systems operating at high carrier frequencies and small distances, traditional radar propagation models do not accurately…

Signal Processing · Electrical Eng. & Systems 2024-03-28 François De Saint Moulin , Guillaume Thiran , Christophe Craeye , Luc Vandendorpe , Claude Oestges

Despite recent advancements in semantic segmentation, where and what pixels are hard to segment remains largely unexplored. Existing research only separates an image into easy and hard regions and empirically observes the latter are…

Computer Vision and Pattern Recognition · Computer Science 2024-03-26 Linwei Chen , Lin Gu , Ying Fu

Neural Radiance Fields (NeRFs) have unmatched fidelity on large, real-world scenes. A common approach for scaling NeRFs is to partition the scene into regions, each of which is assigned its own parameters. When implemented naively, such an…

Computer Vision and Pattern Recognition · Computer Science 2024-06-18 Clinton Wang , Peter Hedman , Polina Golland , Jonathan T. Barron , Daniel Duckworth

Spatial aliasing affects spaced microphone arrays, causing directional ambiguity above certain frequencies, degrading spatial and spectral accuracy of beamformers. Given the limitations of conventional signal processing and the scarcity of…

Audio and Speech Processing · Electrical Eng. & Systems 2025-10-21 Mateusz Guzik , Giulio Cengarle , Daniel Arteaga

Large-aperture coprime arrays (CAs) are expected to achieve higher sensing resolution than conventional dense arrays (DAs), yet with lower hardware and energy cost. However, existing CA far-field localization methods cannot be directly…

Signal Processing · Electrical Eng. & Systems 2024-11-05 Hongqiang Cheng , Changsheng You , Cong Zhou

Recently, we proposed a metasurface design for chiral sensing that (i) results in enhanced chiroptical signals by more than two orders of magnitude for ultrathin, subwavelength, chiral samples over a uniform and accessible area, (ii) allows…

Optics · Physics 2021-08-18 Sotiris Droulias , Lykourgos Bougas

High-quality imaging in photoacoustic computed tomography (PACT) usually requires a high-channel count system for dense spatial sampling around the object to avoid aliasing-related artefacts. To reduce system complexity, various image…

Image and Video Processing · Electrical Eng. & Systems 2024-09-24 Bowei Yao , Shilong Cui , Haizhao Dai , Qing Wu , Youshen Xiao , Fei Gao , Jingyi Yu , Yuyao Zhang , Xiran Cai

In this paper, we consider the estimation of the unknown parameters of the multiple chirp signal model in presence of additive error. The chirp signals are quite common in many areas of science and engineering, specially sonar, radar, audio…

Signal Processing · Electrical Eng. & Systems 2018-07-04 Swagata Nandi , Debasis Kundu

Ptychography is an imaging technique which involves a sample being illuminated by a coherent, localized probe of illumination. When the probe interacts with the sample, the light is diffracted and a diffraction pattern is detected. Then the…

Numerical Analysis · Mathematics 2023-01-31 Mark Iwen , Michael Perlmutter , Mark Philip Roach

Recent advances in 3D Gaussian splatting have significantly improved real-time novel view synthesis, yet insufficient geometric constraints during scene optimization often result in blurred reconstructions of fine-grained details,…

Computer Vision and Pattern Recognition · Computer Science 2025-08-15 Zheng Zhou , Jia-Chen Zhang , Yu-Jie Xiong , Chun-Ming Xia

Estimators for $n$-point clustering statistics in Fourier-space demand that modern surveys of large-scale structure be transformed to Cartesian coordinates to perform Fast Fourier Transforms (FFTs). In this work, we explore this…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-05 Steven Cunnington , Laura Wolz

In this work, a multiple-expert binarization framework for multispectral images is proposed. The framework is based on a constrained subspace selection limited to the spectral bands combined with state-of-the-art gray-level binarization…

Computer Vision and Pattern Recognition · Computer Science 2015-08-27 Reza Farrahi Moghaddam , Mohamed Cheriet

Neural Radiance Fields (NeRF) with hybrid representations have shown impressive capabilities for novel view synthesis, delivering high efficiency. Nonetheless, their performance significantly drops with sparse input views. Various…

Computer Vision and Pattern Recognition · Computer Science 2024-12-16 Yuru Xiao , Deming Zhai , Wenbo Zhao , Kui Jiang , Junjun Jiang , Xianming Liu

The paper aims at removing the aliasing effects of the whole focal stack generated from a sparse-sampled {4D} light field, while keeping the consistency across all the focal layers. We first explore the structural characteristics embedded…

Image and Video Processing · Electrical Eng. & Systems 2022-04-04 Yaning Li , Xue Wang , Hao Zhu , Guoqing Zhou , Qing Wang

Near-field beamforming enables target discrimination in both range (axial) and angle (lateral) dimensions. Elevated sidelobes along either dimension, however, increase susceptibility to interference and degrade detection performance.…

Signal Processing · Electrical Eng. & Systems 2025-11-18 Ahmed Hussain , Ahmed Sultan , Asmaa Abdallah , Abdulkadir Celik , Ahmed M. Eltawil

Correlation filters (CFs) are a class of classifiers that are attractive for object localization and tracking applications. Traditionally, CFs have been designed in the frequency domain using the discrete Fourier transform (DFT), where…

Computer Vision and Pattern Recognition · Computer Science 2016-11-18 Joseph A. Fernandez , Vishnu Naresh Boddeti , Andres Rodriguez , B. V. K. Vijaya Kumar

Visual relocalization is a key technique to autonomous driving, robotics, and virtual/augmented reality. After decades of explorations, absolute pose regression (APR), scene coordinate regression (SCR), and hierarchical methods (HMs) have…

Computer Vision and Pattern Recognition · Computer Science 2024-04-16 Fei Xue , Ignas Budvytis , Daniel Olmeda Reino , Roberto Cipolla