Results 261 to 270 of about 255,632 (300)

Harmonic bandpass detection of tdm signals

Microwave and Optical Technology Letters, 1994
AbstractA time division multiplex (TDM) communication system for baseband analog signals is described. The constant amplitude pulse width modulation scheme utilizes small pulse width deviations for short‐haul opticalfiber applications. An enhanced signal‐to‐noise ratio (S / N) for low‐frequency information (< 1000 Hz) may be secured by detecting a ...
V. P. McGinn, R. R. Reis
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Sequential detection of almost-harmonic signals

IEEE Transactions on Signal Processing, 2003
To detect a purely harmonic signal, it is difficult to beat a fast Fourier transform (FFT). However, when the signal is very long and weak, Parker and White (1999) have shown that a sequential probability ratio test (SPRT) operating on magnitude-square FFT data is far more efficient.
MARANO, Stefano, MATTA, Vincenzo, WILLETT P.   +2 more
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Harmonic detection by using neural network

Proceedings of ICNN'95 - International Conference on Neural Networks, 2002
A methodology of harmonic detection in active power filter from the power line by using neural network is presented. Harmonic detection by using Fourier transformation is an advantageous method to compensate a specific harmonic component. However, it needs input data for each cycle of the current waveform and needs time for the analysis in each cycle ...
N. Pecharanin, H. Mitsui, M. Sone
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Low Level Second Harmonic Detection System

Review of Scientific Instruments, 1965
A second harmonic detection system suitable for detailed study of current-voltage characteristics, particularly tunneling characteristics of superconductor and semiconductor junctions, is described. The system is capable of detecting second harmonic voltage changes as low as 10−9 V which allows the fundamental signal level to be ≤kT at a junction ...
D. E. Thomas, J. M. Rowell
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Accurate Detecting Method for Fractional Harmonic

Advanced Materials Research, 2011
This paper introduces a Hopfield neural network theory to deduce the model of the detection of fractional harmonic. It also discusses the setting method of integral parameter. The simulation results show that the method has high precision and the dynamic characteristics of the system are relevant to the integral parameter.
Ping Wang, Bao Hua Cheng, Zhi Bin Zhang
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An Improved Adaptive Harmonic Detection Algorithm

2018 24th International Conference on Automation and Computing (ICAC), 2018
Active power filter (APF) can effectively suppress harmonic current, and harmonic detection is an important part which can directly influence the effect of APF. Based on the traditional adaptive noise cancellation theory (ANCT) harmonic detection method, this paper proposes an improved variable step size adaptive harmonic detection algorithm.
Zhijun Li, Yanan Wang, Baihui Cui
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Neural network approach of harmonics detection

Proceedings of EMPD '98. 1998 International Conference on Energy Management and Power Delivery (Cat. No.98EX137), 2002
This paper describes a novel approach of harmonics detection in a power system which can be used as an alternative to the conventional approaches. The proposed approach uses the multilayer feed forward neural network to determine the harmonic components in a six-pulse bridge converter.
Zin, A.A.M, Rokonuzzaman, M., Shaibon, H., Lo, K.I.   +3 more
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Harmonic Scrubber for Detected Modulation Frequencies

2020
Acoustic signals have long been used to monitor the performance of machinery containing mechanical moving parts, especially machinery used in manufacturing. Rotating components generate harmonic signals with a fundamental frequency corresponding to the period of rotation, although the fundamental frequency and some of the harmonics may be missing.
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Harmonic and Inter-Harmonic Detection Based on FFT and Nonlinear Optimization

Applied Mechanics and Materials, 2012
In order to analyze harmonic and inter-harmonic parameters more accurately, a new detecting method that combined the nonlinear least squares and fast Fourier transform(FFT) was proposed. The FFT was used to produce a rough estimated value of harmonic parameters and then the signal model was set.
Huai Qing Zhang, Ran Liu, Hao Xiong
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Parasitic Harmonic Cancellation for Reliable Tag Detection with Pulsed Harmonic Radar

2019 IEEE Radar Conference (RadarConf), 2019
In this paper, we address the problem of harmonic radar tag detection in the presence of non-ideal linearisation of radar sensors. Due to extremely low signal levels that are expected from passive harmonic tags, inherent non-linearities of radar sensors coupled with parasitic signal leakage from the transmitter to the receiver constitute major problems
Anastasia Lavrenko, Graeme Woodward, Stephen Pawson   +2 more
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