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Estimation of Spread Spectrum Signal Parameters Utilizing Wavelet Transform Analysis

N. Uzunoglu, A. Amditis, G. Katsoulis, N . Leonis
2005 Radioengineering  
This paper investigates the application of wavelet transform (WT) tothe extraction of particular features of direct sequence spreadspectrum signals.  ...  Thecapabilities focus on the detection of the chipping sequence, while thelimitations refer primarily to the advent of direct sequence CDMAsignals.  ...  Continuous Wavelet Transform (CWT), Discrete Wavelet Transform (DWT): Ability to Detect Signal Discontinuities The most famous among the wavelet transforms are the CWT and the DWT.  ... 
doaj:8cf7941cc70c43909ae6ef6bc3039ac7 fatcat:xqzerkk3une53nvlu6s3onu5um

Detecting specific oscillatory modes in the dynamics of erbium-doped fiber laser

M. O. Zhuravlev, A. A. Koronovskii, O. I. Moskalenko, A. N. Pisarchik, D.-R. Rider, A. E. Hramov
2015 Bulletin of the Russian Academy of Sciences Physics  
The method is based on using a continuous wavelet transform with a mother Morlet wavelet and analyzing the energy of the wavelet spectrum that corresponds to the relevant range of time scales.  ...  A method for determining the oscillatory mode occurring in an erbium-doped fiber laser with a modulated parameter is proposed.  ...  (E(s)) = \$V(s,t 0 f dt 0 . (4) Note that a distinctive feature of the continuous wavelet transform is that this method for analyzing compound chaotic signals enables us to detect the contribution from  ... 
doi:10.3103/s1062873815120266 fatcat:u5mg2etesfaanazct6jun7m3zm

Study on Signal De-Noising for Multi-Channel Automatic Ultrasonic Testing System

Qi Zhang, Li Hou
2016 International Journal of Signal Processing, Image Processing and Pattern Recognition  
An improved wavelet threshold was proposed to remove mixed noise in the echo signal to improve the echo signal-to-noise ratio at the same time.  ...  They could effectively remove interference signals in ultrasonic echo signal by analyzing interference source and dissemination way of automatic ultrasonic flaw detection system for smalldiameter steel  ...  Echo Signal Processing Wavelet Transform De-Noising Basic ideas of wavelet de-noising can be summed up in Figure 3 : noise signal is decomposed into multi-scale using the wavelet transform with binary  ... 
doi:10.14257/ijsip.2016.9.8.27 fatcat:qoiykjeb7fbf7kvlqaamlgkqae

Modulation Detection In The Time-Frequency Domain For Cognitive Radio Systems

Aydin Akan, Yesim Hekim Tanc
2011 Zenodo  
In [7] the authors use Wavelet Transform (WT) to extract a distinctive feature to classify the digitally modulated signals.  ...  The rapid development in communication protocols and interfaces leads the use of different type of signal and modulation.  ... 
doi:10.5281/zenodo.42689 fatcat:rerb7vfz7neatoe6cofmoir7o4

A Novel Demodulation System Based on Continuous Wavelet Transform

Lanting Fang, Lenan Wu, Yudong Zhang
2015 Mathematical Problems in Engineering  
Considering the problem of EBPSK signal demodulation, a new approach based on the wavelet scalogram using continuous wavelet transform is proposed.  ...  Index terms are signal demodulation, adaptive wavelet, continuous wavelet transform, and BER.  ...  Acknowledgments The work is supported by the National Key Technology R&D Program under the Grant 2012BAH15B00 and the National Natural Science Foundation of China (nos. 61271204 and 610011024).  ... 
doi:10.1155/2015/513849 fatcat:emohuq4bh5esveqfr2nt3nojxm

Wavelet-based ann approach for transmission line protection

F. Martin, J.A. Aguado
2003 IEEE Transactions on Power Delivery  
The proposed technique consists of a preprocessing module based on discrete wavelet transforms (DWTs) in combination with an artificial neural network (ANN) for detecting and classifying fault events.  ...  Index Terms-Artificial neural networks, discrete wavelet transform, transmission line protection.  ...  The wavelet transform not only decomposes a signal into frequency bands, but also, unlike the Fourier transform, provides a nonuniform division of the frequency domain (i.e., the wavelet transform uses  ... 
doi:10.1109/tpwrd.2003.817523 fatcat:ojixoxblibchnapdhmioz2a7ju

Channel Estimation of Wavelet-Based MIMO-OFDM Systems Using Least Square Estimator and KALMAN Algorithm

Dishya Sharma
2018 International Journal for Research in Applied Science and Engineering Technology  
Multiple signals are transmitted from different antennas using the same frequency and separated space.  ...  In this paper, we analyze and implement various estimation techniques for MIMO-OFDM Systems such as Least Squares (LS) and KALMAN by using different modulations like QAM (Quadrature Amplitude Modulation  ...  Channel estimation is used for noise detection and decoding of the wireless signal to decrease noise and the interference [2] .  ... 
doi:10.22214/ijraset.2018.4687 fatcat:76hhrho3ifeu7h5cttwiiviemm

Voltage Sag Detection through Wavelet Energy Coefficient

S. Debdas, S. Paikra, T. Roy Choudhury
2013 International Journal of Computer and Electrical Engineering  
In this paper a novel approach of wavelet transform has been carried out to detect voltage sag duration and magnitude.  ...  In this work, a new voltage sag detection method based on wavelet transform is developed. Voltage sag detection algorithms, so far have provided their efficiency and computational ability.  ...  Open the source menu and notice that the specified type of amplitude variation is a sinusoidal modulation (Amplitude of the modulation = 0.5 Pu, Frequency of the modulation = 1 Hz).  ... 
doi:10.7763/ijcee.2013.v5.736 fatcat:clk5bjnvo5ey3eirhojo6un6iq

Wavelet energy moment and neural networks based particle swarm optimisation for transmission line protection

Salah Sabry Daiboun Sahel, Mohamed Boudour
2019 Bulletin of Electrical Engineering and Informatics  
In this study, a combined approach of discrete wavelet transform analysis and a feed forward neural networks algorithm to detect and classify transmission line faults.  ...  all the ten types of faults using Matlab/Simulink.  ...  Fault detection and classification are carried out in separate modules 10 modules for detection and 4 modules to identify and classify the faults up to 99% of line within one cycle time.The fault signals  ... 
doi:10.11591/eei.v8i1.1214 fatcat:37cgmax4vba4penl4ytgxhln2q

Open Architecture Software Design for Online Spindle Health Monitoring

Li Zhang, Ruqiang Yan, Robert X. Gao, Kang B. Lee
2007 Instrumentation and Measurement Technology Conference (IMTC), Proceedings, IEEE  
The capability of effective and efficient spindle defect detection and localization has been realized using the analytic wavelet-based envelope spectrum algorithm.  ...  The software is implemented using the graphical programming language of LabVIEW, and presents the spindle health status in two types of windows: simplified spindle condition display and warning window  ...  Since the imaginary part of a complex wavelet is inherently the Hilbert transform of its real part, the wavelet coefficients of a transformed signal, in which the complex wavelet is used as the base wavelet  ... 
doi:10.1109/imtc.2007.379290 fatcat:eqjplc4qargehfqd46dl66toyq

Low Probability of Intercept Triangular Modulated Frequency Modulated Continuous Wave Signal Characterization Comparison using the Spectrogram and the Scalogram

Daniel L. Stevens, Stephanie A. Schuckers
2017 Global Journal of Researches in Engineering  
Also used were: percent detection, lowest signal-to-noise ratio for signal detection, and plot (processing) time.  ...  The following metrics were used for evaluation: percent error of: carrier frequency, modulation bandwidth, modulation period, chirp rate, and time-frequency localization (x and y direction).  ...  The basic difference between the STFT and the wavelet transform is that the STFT uses a fixed signal analysis window, whereas the wavelet transform uses short windows at high frequencies and long windows  ... 
doi:10.34257/gjrefvol17is2pg37 fatcat:zxdhbzpqo5bt3pve766fihu7oi

Cognitive Radio Communications for Vehicular Technology – Wavelet Applications [chapter]

Murroni Maurizio, Popescu Vl
2011 Vehicular Technologies: Increasing Connectivity  
can be used for detecting the type of signal.  ...  Detected features are number of signals, their modulation types, symbol rates and presence of interferers.  ...  This chapter is distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike-3.0 License, which permits use, distribution and reproduction for non-commercial purposes, provided  ... 
doi:10.5772/14913 fatcat:jwfirzz6a5ea5hdg7bu4k45xyi

De-noising of partial discharge signal using wavelet transform for GIS under HVDC

Guoming Wang, Han Hu, Min Tang, Jinlong Gong, Yifan Wang, Hong-Keun Ji, Gyung-Suk Kil
2020 Journal of Electrical Engineering  
Therefore, this paper dealt with the discrimination of PD signal based on wavelet transform (WT) techniques for HVDC GIS, aiming to improve the sensitivity and accuracy of insulation diagnosis.  ...  The WT techniques were used to discriminate PD pulse sequences from background noise, amplitude modulation radio interference, non-sinusoidal noise, and switching impulse and the effectiveness was compared  ...  The wavelet techniques were used for discriminating DEPtype and DOP-type PD sequences that were actually detected from artificial defects and interfered by background noise, amplitude modulation radio  ... 
doi:10.2478/jee-2020-0034 fatcat:aicftvawwreq3d3ll4ayoxwkre

Wavelet based multicarrier CDMA system

Nasser Hamad, Maen Takruri, Mahdi Barhoush
2019 International Journal of Electrical and Computer Engineering (IJECE)  
This paper studies and simulates the Discrete Wavelet Transform based Multicarrier CDMA and compares it with the Discrete Fourier Transform based one using different number of sub carriers, and different  ...  modulation techniques.  ...  In this simulation, we compare the performance of the wavelet based MC-CDMA over the Fourier based one in terms of and PAPR using different types of wavelet families, modulation techniques, variable number  ... 
doi:10.11591/ijece.v9i4.pp3051-3059 fatcat:5gy6fecrdvdkhpiytthghvbqce

Fault Diagnosis in Medium Voltage Drive Based on Combination of Wavelet transform and Support Vector Machine

Xudong Cao, Shaozhe Zhou, Jingze Li, Shaohua Zhang
2016 TELKOMNIKA (Telecommunication Computing Electronics and Control)  
The wavelet transform is used to extract fault features and SVM is used to classify the fault states of a single power unit.  ...  This method combines wavelet transform (WT) and support vector machine (SVM).  ...  "Sine", "Sine1" and "Sine2" modules work as sine wave generator. Wavelet Transform of Power Module's Output Voltage Wavelet transform is very sensitive to singular point of signal.  ... 
doi:10.12928/telkomnika.v14i4.4033 fatcat:vkfwv62injdhng4ea4zungej44
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