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Understanding Harmonic Structures Through Instantaneous Frequency [PDF]
IEEE Open Journal of Signal Processing, 2022 The analysis of harmonics and non-sinusoidal waveform shape in time-series data is growing in importance. However, a precise definition of what constitutes a harmonic is lacking. In this paper, we propose a rigorous definition of when to consider signals
Marco S. Fabus +3 more
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High-Concentration Time-Frequency Representation and Instantaneous Frequency Estimation of Frequency-Crossing Signals [PDF]
SensorsFrequency-crossing signals are widely found in nature and various engineering systems. Currently, achieving high-resolution time-frequency (TF) representation and accurate instantaneous frequency (IF) estimation for these signals presents a challenge and
Hui Li +4 more
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Power-Independent Microwave Photonic Instantaneous Frequency Measurement System [PDF]
SensorsThe ability to perform instantaneous frequency measurement (IFM) of unknown microwave signals holds significant importance across various application domains. This paper presents a power-independent microwave photonic IFM system.
Ruiqiong Wang, Yongjun Li
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Fluctuations in instantaneous frequency predict alpha amplitude during visual perception. [PDF]
Nat Commun, 2017 Rhythmic neural activity in the alpha band (8-13 Hz) is thought to have an important role in the selective processing of visual information. Typically, modulations in alpha amplitude and instantaneous frequency are thought to reflect independent ...
Nelli S +3 more
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Photonic instantaneous frequency measurement of wideband microwave signals. [PDF]
PLoS ONE, 2017 We propose a photonic system for instantaneous frequency measurement (IFM) of wideband microwave signals with a tunable measurement range and resolution based on a polarization-maintaining fiber Bragg grating (PM-FBG). Firstly, in order to be insensitive
Yueqin Li +5 more
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Instantaneous Frequency Estimation Algorithm for Power Systems [PDF]
JES: Journal of Engineering Sciences, 2022 This paper deals with the problem of the Instantaneous Frequency (IF) estimation of power systems, to be adopted for example in Phasor Measurement Units (PMUs) used for monitoring, control, and protection.
Christina Aziz +2 more
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IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2021 The instantaneous frequency (IF) image is proposed in this work. It is obtained by the differentiation of the instantaneous phase (IP) image, which in turn is calculated by replacing the amplitude information with the IP in the delay-and-sum beamforming.
Vander Teixeira Prado +1 more
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Remote Sensing, 2023 In ground-penetrating radar (GPR) or lunar-penetrating radar (LPR) interpretation, instantaneous attributes (e.g., instantaneous energy and instantaneous frequency) are often utilized for attribute analysis, and they can also be integrated into a new ...
Xuebing Zhang +6 more
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Instantaneous Frequency-Embedded Synchrosqueezing Transform for Signal Separation
Frontiers in Applied Mathematics and Statistics, 2022 The synchrosqueezing transform (SST) and its variants have been developed recently as an alternative to the empirical mode decomposition scheme to model a non-stationary signal as a superposition of amplitude- and frequency-modulated Fourier-like ...
Qingtang Jiang +3 more
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Frequency Domain Repercussions of Instantaneous Granger Causality
Entropy, 2021 Using directed transfer function (DTF) and partial directed coherence (PDC) in the information version, this paper extends the theoretical framework to incorporate the instantaneous Granger causality (iGC) frequency domain description into a single ...
Luiz A. Baccalá, Koichi Sameshima
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