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Classification with Joint Time-Frequency Scattering [article]

Joakim Andén, Vincent Lostanlen, Stéphane Mallat
2018 arXiv   pre-print
We introduce the joint time-frequency scattering transform, a locally time-shift invariant representation which characterizes the multiscale energy distribution of a signal in time and frequency.  ...  We consider the progression from mel-spectrograms to time scattering and joint time-frequency scattering transforms, illustrating the relationship between increased discriminability and refinements of  ...  We therefore expect the joint time-frequency scattering to provide only limited improvement over time scattering.  ... 
arXiv:1807.08869v1 fatcat:4drks7dthfcnro2yokbt6ucuce

Joint time-frequency scattering for audio classification

Joakim Anden, Vincent Lostanlen, Stephane Mallat
2015 2015 IEEE 25th International Workshop on Machine Learning for Signal Processing (MLSP)  
We introduce the joint time-frequency scattering transform, a time shift invariant descriptor of time-frequency structure for audio classification.  ...  It is obtained by applying a two-dimensional wavelet transform in time and log-frequency to a time-frequency wavelet scalogram.  ...  Over a fixed time interval, MFSCs measure the signal frequency energy over mel-frequency intervals of constant-Q bandwidth.  ... 
doi:10.1109/mlsp.2015.7324385 dblp:conf/mlsp/AndenLM15 fatcat:d5z4waomnjcqjh47njrhl6fuhm

Playing Technique Recognition by Joint Time–Frequency Scattering

Changhong Wang, Vincent Lostanlen, Emmanouil Benetos, Elaine Chew
2020 ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)  
In this paper, we propose a recognition system based on the joint time-frequency scattering transform (jTFST) for pitch evolution-based playing techniques (PETs), a group of playing techniques with monotonic  ...  The jTFST represents spectro-temporal patterns in the time-frequency domain, capturing discriminative information of PETs.  ...  Diagram of the joint time-frequency scattering transform.  ... 
doi:10.1109/icassp40776.2020.9053474 dblp:conf/icassp/WangLBC20 fatcat:6uz6goh465eazpje4ihdrby2jq

Joint Time-Frequency Analysis of Transient Electromagnetic Scattering from a Subsurface Target

Hoi-Shun Lui, M. Persson, N. V. Z. Shuley
2012 IEEE Antennas & Propagation Magazine  
Attempts have been made to analytically and numerically study the transient scattering problem using time-frequency (TF) analysis.  ...  Using this technique, the occurrences of the scattering events and their frequency content can be revealed, which leads to further information about the actual scattering behavior.  ...  One possible approach to assist in the development of better algorithms for subsurface scattering is to study the timevariant transient response in a signal-processing context using joint time-frequency  ... 
doi:10.1109/map.2012.6348122 fatcat:tuc6bxo2gbcfhcubolqz7mu4jy

Joint Time-Frequency Signal Processing Scheme in Forward Scattering Radar with a Rotational Transmitter

Raja Raja Abdullah, Azizi Mohd Ali, Mohd Rasid, Nur Abdul Rashid, Asem Ahmad Salah, Aris Munawar
2016 Remote Sensing  
In this paper, a novel signal processing for the new mode of FSR system based on the signal's joint time-frequency is proposed and discussed.  ...  Abstract: This paper explores the concept of a Forward Scattering Radar (FSR) system with a rotational transmitter for target detection and localization.  ...  A novel detection technique based on the signal's joint Time-Frequency (T-F) is integrated with the proposed FSR system.  ... 
doi:10.3390/rs8121028 fatcat:im3wh4x3zzbq3ozafrmhxaad3i

Empirical relationship between local scattering function and joint probability density function

Michael Walter, Thomas Zemen, Dmitriy Shutin
2015 2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC)  
The LSF is hereby used to process the measurement data and extract information like the stationarity time.  ...  In this paper, a relation between LSF and the joint pdf is investigated.  ...  f denoting continuous time and frequency.  ... 
doi:10.1109/pimrc.2015.7343359 dblp:conf/pimrc/WalterZS15 fatcat:2jtppjtasfd4hdghmn3iilqkaa

Joint Delay Doppler Probability Density Functions for Air-to-Air Channels

Michael Walter, Dmitriy Shutin, Uwe-Carsten Fiebig
2014 International Journal of Antennas and Propagation  
Novel joint time-variant delay Doppler probability density functions are presented.  ...  This allows us to obtain closed form mathematical expressions for the probability density functions, which can then be calculated for any delay and Doppler frequency at arbitrary times numerically.  ...  These joint delay Doppler pdfs allow to simulate the bit error rate of a time-variant air-to-air channel at arbitrary times.  ... 
doi:10.1155/2014/814218 fatcat:nntg5m2wrjgureqd2wbpva7eee

Micro-Doppler Effect Removal in ISAR Imaging by Promoting Joint Sparsity in Time-Frequency Domain

2018 Sensors  
In contrast, the Doppler frequency of the micromotion scatterer varies with the slow time [13] .  ...  Based on the distinct patterns in the time-frequency domain, this paper proposes a joint sparsity-based ISAR imaging method to remove the m-D effect generated by the micromotion scatterers with small rotating  ...  It is claimed that the Doppler frequency of the micromotion scatterer is slow time variant while the main body scatterer has a constant Doppler frequency, indicating the joint sparsity property in the  ... 
doi:10.3390/s18040951 pmid:29570641 pmcid:PMC5948648 fatcat:hphswyh7wjbcxbldyq6ogypzay

Differentiable Time-Frequency Scattering in Kymatio [article]

John Muradeli, Cyrus Vahidi, Changhong Wang, Han Han, Vincent Lostanlen, Mathieu Lagrange, George Fazekas
2022 arXiv   pre-print
Joint time-frequency scattering (JTFS) is a convolutional operator in the time-frequency domain which extracts spectrotemporal modulations at various rates and scales.  ...  In this paper, we present an implementation of time-frequency scattering in Kymatio, an open-source Python package for scattering transforms.  ...  TIME-FREQUENCY SCATTERING Proposed in [7] , the joint time-frequency scattering (JTFS) transform captures the spectrotemporal modulations of a signal at var- ious rates and scales.  ... 
arXiv:2204.08269v3 fatcat:p3ax3rgod5dhze2ykeltgqioy4

Geometric Analysis of the Doppler Frequency for General Non-Stationary 3D Mobile-to-Mobile Channels based on Prolate Spheroidal Coordinates

Michael Walter, Dmitriy Shutin, Martin Schmidhammer, David W. Matolak, Alenka Zajic
2020 IEEE Transactions on Vehicular Technology  
The presented theory allows describing any time-variant, single-bounce, mobile-to-mobile scattering channel.  ...  Mobile-to-mobile channels often exhibit time-variant Doppler frequency shifts due to the movement of transmitter and receiver.  ...  Thus, the scattering power is accounted for in the joint delay Doppler pdf for the first time.  ... 
doi:10.1109/tvt.2020.3011408 fatcat:iqjtrterkjbj3l2bhlx4um7qpy

Time-Frequency Scattering Accurately Models Auditory Similarities Between Instrumental Playing Techniques [article]

Vincent Lostanlen, Christian El-Hajj, Mathias Rossignol, Grégoire Lafay, Joakim Andén, Mathieu Lagrange
2020 arXiv   pre-print
Our model relies on joint timefrequency scattering features to extract spectrotemporal modulations as acoustic features.  ...  An ablation study demonstrates that removing either the joint timefrequency scattering transform or the metric learning algorithm noticeably degrades performance.  ...  Moreover, separable time-frequency scattering has a lower algorithmic complexity than joint time-frequency scattering.  ... 
arXiv:2007.10926v2 fatcat:54efqx4xbvcj5befxjb5ejfhr4

Special Issue of the International Journal of Numerical Modelling: Electronic Networks, Devices and Fields on Wavelets in Electromagnetics

L Katehi, M Krumpholz
1998 International journal of numerical modelling  
Wavelets, or more generally joint time-frequency representations, have recently also found useful applications in processing electromagnetic data.  ...  This can oftentimes lead to more insights into the complex electromagnetic wave propagation and scattering mechanisms than what is available in the traditional time or frequency alone.  ...  Wavelets, or more generally joint time-frequency representations, have recently also found useful applications in processing electromagnetic data.  ... 
doi:10.1002/(sici)1099-1204(199801/02)11:1<1::aid-jnm296>3.0.co;2-k fatcat:73xalujjsbenpeiybhsnrczrp4

Page 891 of American Society of Civil Engineers. Collected Journals Vol. 124, Issue 8 [page]

1998 American Society of Civil Engineers. Collected Journals  
matrix for joint J; scattering coefficient for member MJ to member JK; global source matrix; source vector for joint J; source wave emanating from joint J in member JM; time; rise time response of strain  ...  J; number of joints in entire structure; number of neighboring joints for joint J; propagation matrix; reverberation matrix; radius of gyration of member cross section; global scattering matrix; scattering  ... 

Time–frequency scattering accurately models auditory similarities between instrumental playing techniques

Vincent Lostanlen, Christian El-Hajj, Mathias Rossignol, Grégoire Lafay, Joakim Andén, Mathieu Lagrange
2021 EURASIP Journal on Audio, Speech, and Music Processing  
Our model relies on joint timefrequency scattering features to extract spectrotemporal modulations as acoustic features.  ...  An ablation study demonstrates that removing either the joint timefrequency scattering transform or the metric learning algorithm noticeably degrades performance.  ...  Moreover, separable time-frequency scattering has a lower algorithmic complexity than joint time-frequency scattering.  ... 
doi:10.1186/s13636-020-00187-z pmid:33488686 pmcid:PMC7801324 fatcat:5tmi3yteuffvjcfon5gedecefe

Multipixel system for gigahertz frequency-domain optical imaging of finger joints

Uwe J. Netz, Jürgen Beuthan, Andreas H. Hielscher
2008 Review of Scientific Instruments  
At these low frequencies, their ability to provide accurate data for small tissue geometries such as encountered in imaging of finger joints or rodents is limited.  ...  However, most of the frequency domain systems presented so far operate with source modulation frequencies below 150 MHz.  ...  As the bone and skin complex have the same scattering coefficient, the drop in ⌽ occurs because of the low scattering fluid in the capsule volume and the joint gap.  ... 
doi:10.1063/1.2840344 pmid:18377031 fatcat:2qpepywz5ng4rdufkeuem62dpu
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