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We propose and validate a novel optical semantic transmission scheme using multimode fiber (MMF). By leveraging the frequency sensitivity of intermodal dispersion in MMFs, we achieve high-dimensional semantic encoding and decoding in the…

Signal Processing · Electrical Eng. & Systems 2024-09-04 Zheng Gao , Ting Jiang , Mingming Zhang , Hao Wu , Ming Tang

Efficient estimators of Fourier-space statistics for large number of objects rely on Fast Fourier Transforms (FFTs), which are affected by aliasing from unresolved small scale modes due to the finite FFT grid. Aliasing takes the form of a…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-09 Emiliano Sefusatti , Martin Crocce , Roman Scoccimarro , Hugh Couchman

In many mechanical, electrical, and general physical systems evolving over time or space, spectral analysis methods as Fast Fourier Transform (FFT), Short Term Fourier Transform (STFT), Power Spectrum Density (PSD) plays a very important…

Signal Processing · Electrical Eng. & Systems 2023-06-21 Andreas Tuor , Nico Canzani , Tobias Rüggeberg , Stefan Gorenflo , Gerd Simons , Bruno Bättig , Daniel Iseli

We consider the problem of estimating sparse communication channels in the MIMO context. In small to medium bandwidth communications, as in the current standards for OFDM and CDMA communication systems (with bandwidth up to 20 MHz), such…

Networking and Internet Architecture · Computer Science 2016-11-17 Yann Barbotin , Ali Hormati , Sundeep Rangan , Martin Vetterli

Low-light image enhancement is a classical computer vision problem aiming to recover normal-exposure images from low-light images. However, convolutional neural networks commonly used in this field are good at sampling low-frequency local…

Computer Vision and Pattern Recognition · Computer Science 2022-09-19 Yunliang Zhuang , Zhuoran Zheng , Chen Lyu

Recently, we proposed short-time Fourier transform (STFT)-based loss functions for training a neural speech waveform model. In this paper, we generalize the above framework and propose a training scheme for such models based on spectral…

Audio and Speech Processing · Electrical Eng. & Systems 2019-04-09 Shinji Takaki , Hirokazu Kameoka , Junichi Yamagishi

Communication efficiency is a widely recognised research problem in Federated Learning (FL), with recent work focused on developing techniques for efficient compression, distribution and aggregation of model parameters between clients and…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-09-10 Chamath Palihawadana , Nirmalie Wiratunga , Anjana Wijekoon , Harsha Kalutarage

Perceptive mobile networks (PMN) have been widely recognized as a pivotal pillar for the sixth generation (6G) mobile communication systems. However, the asynchronicity between transmitters and receivers results in velocity and range…

Signal Processing · Electrical Eng. & Systems 2024-09-04 Xiao-Yang Wang , Shaoshi Yang , Hou-Yu Zhai , Christos Masouros , J. Andrew Zhang

The mitigation of nonlinear distortion caused by power amplifiers (PA) in Orthogonal Frequency Division Multiplexing (OFDM) systems is an essential issue to enable energy efficient operation. In this work we proposed a new algorithm for…

Information Theory · Computer Science 2015-07-02 Wasim Amjad , Javier García , Jawad Munir , Amine Mezghani , Josef A. Nossek

Detecting fast-moving objects, such as unmanned aerial vehicle (UAV), from event camera data is challenging due to the sparse, asynchronous nature of the input. Traditional Discrete Fourier Transforms (DFT) are effective at identifying…

Computer Vision and Pattern Recognition · Computer Science 2026-03-10 Michael Bezick , Majid Sahin

Convolutional neural networks (CNNs) have a large number of variables and hence suffer from a complexity problem for their implementation. Different methods and techniques have developed to alleviate the problem of CNN's complexity, such as…

Computer Vision and Pattern Recognition · Computer Science 2020-04-07 Kamran Chitsaz , Mohsen Hajabdollahi , Nader Karimi , Shadrokh Samavi , Shahram Shirani

Deep learning has delivered its powerfulness in many application domains, especially in image and speech recognition. As the backbone of deep learning, deep neural networks (DNNs) consist of multiple layers of various types with hundreds to…

Machine Learning · Computer Science 2017-12-14 Sheng Lin , Ning Liu , Mahdi Nazemi , Hongjia Li , Caiwen Ding , Yanzhi Wang , Massoud Pedram

Nonuniform Fourier data are routinely collected in applications such as magnetic resonance imaging, synthetic aperture radar, and synthetic imaging in radio astronomy. To acquire a fast reconstruction that does not require an online inverse…

Numerical Analysis · Mathematics 2016-10-05 Anne Gelb , Guohui Song

The capacity of a discrete-time model of optical fiber described by the split-step Fourier method (SSFM) as a function of the signal-to-noise ratio $\text{SNR}$ and the number of segments in distance $K$ is considered. It is shown that if…

Information Theory · Computer Science 2021-09-28 Milad Sefidgaran , Mansoor Yousefi

In this paper, we propose a faster-than-Nyquist (FTN) non-orthogonal frequency-division multiplexing (NOFDM) scheme for visible light communications (VLC) where the multiplexing/demultiplexing employs the inverse fractional cosine transform…

Information Theory · Computer Science 2017-06-28 Ji Zhou , Yaojun Qiao , Tiantian Zhang , Jinlong Wei , Qixiang Cheng , Qi Wang , Zhanyu Yang , Aiying Yang , Yueming Lu

In long-distance fiber optic transmission, the optic fiber link and erbium-doped fiber amplifiers can introduce excessive noise, which reduces the optical signal-to-noise ratio (OSNR). The narrow-band optical filters can be used to…

Optics · Physics 2024-08-05 Mingwen Zhu , Shangsu Ding , Zhixue Li , Song Yu , Jianming Shang , Bin Luo

Fast Fourier Transform (FFT) is one of the most important tools in digital signal processing. FFT costs O(N \log N) for transforming a signal of length N. Recently, Sparse Fourier Transform (SFT) has emerged as a critical issue addressing…

Data Structures and Algorithms · Computer Science 2015-05-25 Sung-Hsien Hsieh , Chun-Shien Lu , Soo-Chang Pei

In order to efficiently image a non-absorbing sample (a phase object), dedicated phase contrast optics are required. Typically, these optics are designed with the assumption that the sample is weakly scattering, implying a linear relation…

Optics · Physics 2020-10-22 Stewart Koppell , Mark Kasevich

Modern power systems face new operational hurdles due to the increasing adoption of inverter-coupled distributed energy resources, which impact system stability and control. Central to these challenges is the dynamic nature of grid…

Systems and Control · Electrical Eng. & Systems 2025-09-10 Phuoc Sang Nguyen , Ghavameddin Nourbakhsh , Gerard Ledwich

Signal propagation in an optical fiber can be described by the nonlinear Schr\"odinger equation (NLSE). The NLSE has no known closed-form solution, mostly due to the interaction of dispersion and nonlinearities. In this paper, we present a…

Signal Processing · Electrical Eng. & Systems 2024-01-25 Vinícius Oliari , Erik Agrell , Gabriele Liga , Alex Alvarado