Topic
Time–frequency analysis
About: Time–frequency analysis is a research topic. Over the lifetime, 5407 publications have been published within this topic receiving 104346 citations.
Papers published on a yearly basis
Papers
More filters
••
25 Mar 2012TL;DR: Benefiting from advances both in the inversion of the CQT and in statistical modeling, it is shown how recent techniques designed for music analysis can also be used for source separation with encouraging results, thus opening the path to many crossovers between separation and analysis.
Abstract: Dimension reduction techniques such as Nonnegative Tensor Factorization are now classical for both source separation and estimation of multiple fundamental frequencies in audio mixtures. Still, few studies jointly addressed these tasks so far, mainly because separation is often based on the Short Term Fourier Transform (STFT) whereas recent music analysis algorithms are rather based on the Constant-Q Transform (CQT). The CQT is practical for pitch estimation because a pitch shift amounts to a translation of the CQT representation, whereas it produces a scaling of the STFT. Conversely, no simple inversion of the CQT was available until recently, preventing it from being used for source separation. Benefiting from advances both in the inversion of the CQT and in statistical modeling, we show how recent techniques designed for music analysis can also be used for source separation with encouraging results, thus opening the path to many crossovers between separation and analysis.
36 citations
••
TL;DR: The proposed model may be regarded as a stochastic optimization approach to the problem of searching for an optimal composition of dictionary elements, and the main motivation is the application of this model to construct adaptive atomic analyzers, based on overcomplete but sparse representations.
36 citations
••
TL;DR: A dual-frequency radar, which estimates the range of a target based on the phase difference between two closely spaced frequencies, suffers from two drawbacks: it cannot deal with multiple moving targets, and it has poor performance in noisy environments.
Abstract: A dual-frequency radar, which estimates the range of a target based on the phase difference between two closely spaced frequencies, has been shown to be a cost-effective approach to accomplish both range-to-motion estimation and tracking. This approach, however, suffers from two drawbacks: it cannot deal with multiple moving targets, and it has poor performance in noisy environments. In this letter, we propose the use of time-frequency signal representations to overcome these drawbacks. The phase, and subsequently the range information, is obtained based on the moving target instantaneous Doppler frequency law, which is provided through time-frequency signal representations. The case of multiple moving targets is handled by separating the different Doppler signatures prior to phase estimation.
36 citations
••
TL;DR: In this paper, the Hilbert-Huang transform (HHT) was introduced to the phase-sensitive optical time-domain reflectometer sensor system for time-frequency analysis, and the Hilbert spectral analysis made the instantaneous frequency meaningful, and acquired the high frequency resolution.
Abstract: Time-frequency analysis is a practical method to analyze the characteristics of vibration signals. We introduce the Hilbert–Huang transform (HHT) to the phase-sensitive optical time-domain reflectometer sensor system for time-frequency analysis. The Hilbert spectral analysis makes the instantaneous frequency meaningful, and acquires the high frequency resolution. Compared with other time-frequency analysis methods, such as the short-time Fourier transform and the continuous wavelet transform, HHT presents high frequency resolution for both stationary and nonstationary signals, and with much less time consuming.
36 citations
••
TL;DR: A general framework by exploiting the unique capability of generalized demodulation to transform an arbitrary time-varying instantaneous frequency into a constant frequency is proposed and the principle and advantage of generalized adaptive mode decomposition (GAMD) are illustrated through numerical simulation.
36 citations