English
Related papers

Related papers: Adaptive Synchrosqueezing Transform with a Time-Va…

200 papers

Biomedical signal classification presents unique challenges due to long sequences, complex temporal dynamics, and multi-scale frequency patterns that are poorly captured by standard transformer architectures. We propose WaveFormer, a…

Machine Learning · Computer Science 2026-02-13 Habib Irani , Bikram De , Vangelis Metsis

Modeling spatiotemporal dynamical systems is a fundamental challenge in machine learning. Transformer models have been very successful in NLP and computer vision where they provide interpretable representations of data. However, a…

Machine Learning · Computer Science 2023-08-01 Antonio H. de O. Fonseca , Emanuele Zappala , Josue Ortega Caro , David van Dijk

Accurate classification of sleep stages is crucial for the diagnosis and management of sleep disorders. Conventional approaches for sleep scoring rely on manual annotation or features extracted from EEG signals in the time or frequency…

Machine Learning · Computer Science 2025-10-10 Mehdi Zekriyapanah Gashti , Ghasem Farjamnia

Wavelet scattering networks, which are convolutional neural networks (CNNs) with fixed filters and weights, are promising tools for image analysis. Imposing symmetry on image statistics can improve human interpretability, aid in…

Computer Vision and Pattern Recognition · Computer Science 2021-04-26 Andrew K. Saydjari , Douglas P. Finkbeiner

In dynamic acoustic environments with time-varying interferers, effective beamforming requires identifying stationary regions over time. The Capon beamformer, a whitened matched filter constrained to maintain unity gain in the desired…

Signal Processing · Electrical Eng. & Systems 2026-05-26 Manan Mittal , Ryan M. Corey , Diego Cuji , John R. Buck , Andrew C. Singer

This article introduces the class of continuous time locally stationary wavelet processes. Continuous time models enable us to properly provide scale-based time series models for irregularly-spaced observations for the first time, while…

Statistics Theory · Mathematics 2025-03-19 Henry Antonio Palasciano , Marina I. Knight , Guy P. Nason

This study focuses on the analysis of signals containing multiple components with crossover instantaneous frequencies (IF). This problem was initially solved with the chirplet transform (CT). Also, it can be sharpened by adding the…

Numerical Analysis · Mathematics 2024-05-14 Yi-Ju Yen , De-Yan Lu , Sing-Yuan Yeh , Jian-Jiun Ding , Chun-Yen Shen

Accurately calculating time delays between signals is pivotal in many modern physics applications. One approach to estimating these delays is computing the cross-spectrum in the time-frequency domain. Linear time-frequency representations,…

Computational Physics · Physics 2026-03-23 L. de A. Gurgel , J. M. de Araújo , L. D. Machado , P. D. S. de Lima

This paper addresses the problem of efficiently jointly representing a non-stationary multicomponent signal in time and frequency. We introduce a novel enhancement of the time-reassigned synchrosqueezing method designed to compute sharpened…

Signal Processing · Electrical Eng. & Systems 2019-07-23 Dominique Fourer , François Auger

This article introduces a nonparametric approach to multivariate time-varying power spectrum analysis. The procedure adaptively partitions a time series into an unknown number of approximately stationary segments, where some spectral…

Methodology · Statistics 2017-06-28 Zeda Li , Robert T. Krafty

The dual-tree complex wavelet transform (DT-CWT) is known to exhibit better shift-invariance than the conventional discrete wavelet transform. We propose an amplitude-phase representation of the DT-CWT which, among other things, offers a…

Information Theory · Computer Science 2013-07-23 Kunal Narayan Chaudhury , Michael Unser

The finite STFT Synchrosqueezing transform is a time-frequency analysis method that can decompose finite complex signals into time-varying oscillatory components. This representation is sparse and invertible, allowing recovery of the…

Numerical Analysis · Mathematics 2017-09-26 Mozhgan Mohammadpour , Bastiaan Kleijn , Rajab Ali Kamyabi Gol

Recent synthetic speech detection models typically adapt a pre-trained SSL model via finetuning, which is computationally demanding. Parameter-Efficient Fine-Tuning (PEFT) offers an alternative. However, existing methods lack the specific…

Sound · Computer Science 2025-10-30 Yassine El Kheir , Fabian Ritter-Guttierez , Arnab Das , Tim Polzehl , Sebastian Möller

The design and performance of a fully-synchronous multi-GHz analog transient waveform recorder I.C. ("SST") with fast and flexible trigger capabilities is presented. The SST's objective is to provide multi-GHz sample rates with…

Instrumentation and Detectors · Physics 2016-12-06 Stuart A. Kleinfelder , Edwin Chiem , Tarun Prakash

A fast algorithm for Antoine and Vandergheynst's (1998) directional continuous spherical wavelet transform (CSWT) is presented. Computational requirements are reduced by a factor of O(\sqrt{N}), when N is the number of pixels on the sphere.…

Astrophysics · Physics 2007-05-23 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

We introduce a wavelet-based model of local stationarity. This model enlarges the class of locally stationary wavelet processes and contains processes whose spectral density function may change very suddenly in time. A notion of…

Statistics Theory · Mathematics 2008-08-12 Sébastien Van Bellegem , Rainer von Sachs

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

This paper introduces a new tool for time-series analysis: the Sliding Window Discrete Fourier Transform (SWDFT). The SWDFT is especially useful for time-series with local- in-time periodic components. We define a 5-parameter model for…

Methodology · Statistics 2018-07-23 Lee F. Richardson , William F. Eddy

Despite the broad application of the analytic wavelet transform (AWT), a systematic statistical characterization of its magnitude and phase as inhomogeneous random fields on the time-frequency domain when the input is a random process…

Statistics Theory · Mathematics 2025-12-23 Gi-Ren Liu , Yuan-Chung Sheu , Hau-Tieng Wu

The Synchrosqueezing transform is a time-frequency analysis method that can decompose complex signals into time-varying oscillatory components. It is a form of time-frequency reassignment that is both sparse and invertible, allowing for the…

Computational Engineering, Finance, and Science · Computer Science 2014-05-01 Gaurav Thakur