Results 1 to 10 of about 37,062,856 (288)
Analysis of multicarrier frequency diverse array radar over time
IET Signal Processing, 2022 The frequency diverse array (FDA) can provide degrees of freedom in both the range and angle domains by controlling the frequency offset across adjacent elements.
Yingjian Zhao +5 more
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Continuous Time Frequency Domain Analysis of Ф-OTDＲ Nonstationary Signals
Journal of Harbin University of Science and Technology, 2021 Most of the natural vibration signals are stationary and modulated by the interference light signal of the distributed optical fiber vibration sensing system.
XU Tao, LI Li
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Time and Frequency Domain Dynamic Analysis of Offshore Mooring
Journal of Marine Science and Engineering, 2021 The numerical procedures for dynamic analysis of mooring lines in the time domain and frequency domain were developed in this work. The lumped mass method was used to model the mooring lines. In the time domain dynamic analysis, the modified Euler method
Shi He, Aijun Wang
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Approximation of Time-Frequency Shift Equivariant Maps by Neural Networks
MathematicsBased on finite-dimensional time-frequency analysis, we study the properties of time-frequency shift equivariant maps that are generally nonlinear. We first establish a one-to-one correspondence between Λ-equivariant maps and certain phase-homogeneous ...
Dae Gwan Lee
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A Time–Frequency Domain Analysis Method for Variable Frequency Hopping Signal
SensorsA variable frequency hopping (VFH) signal is a kind of frequency hopping (FH) signal that varies both in frequency and dwell time. However, in radio surveillance, the existing methods for unidentified signals using VFH cannot be effectively handled.
Zhengzhi Zeng +3 more
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Time-Frequency Analysis and PDE's
, 2008 We study the action on modulation spaces of Fourier multipliers with symbols $e^{imu(xi)}$, for real-valued functions $mu$ having unbounded second derivatives. We show that if $mu$ satisfies the usual symbol estimates of order $alphageq2$, or if $mu$ is a positively homogeneous function of degree $alpha$, the corresponding Fourier multiplier is ...
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Time–frequency analysis using spiking neural network
Neuromorphic Computing and EngineeringTime–frequency analysis plays a crucial role in various fields, including signal processing and feature extraction. In this article, we propose an alternative and innovative method for time–frequency analysis using a biologically inspired spiking neural ...
Moshe Bensimon +3 more
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Time–frequency analysis of chaotic systems [PDF]
Physica D: Nonlinear Phenomena, 2003 36 pages, 18 ...
Chandre, C, Wiggins, SR, Uzer, T
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INSTANTANEOUS FREQUENCY ESTIMATION USING A LEAST SQUARES TIME-FREQUENCY METHOD
Electrica, 2004 We present a method for estimating the instantaneous frequency of a signal. This method involves the calculation of a time-frequency energy density of the signal, then obtaining an instantaneous frequency estimation from this joint density.
Mahmut ÖZTÜRK, Aydın AKAN
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Time-Frequency Analysis of Sjöstrand’s Class
Revista Matemática Iberoamericana, 2006 We investigate the properties an exotic symbol class of pseudodifferential operators, Sjöstrand's class, with methods of time-frequency analysis (phase space analysis). Compared to the classical treatment, the time-frequency approach leads to striklingly simple proofs of Sjöstrand's fundamental results and to far-reaching generalizations.
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