An analysis of digital Phase-modulated signals is performed based on frequency spectrum which consists of a continuous and a number of discrete components at multiples of clock frequencies. The analysis shows that these components depend on the pulse shape function of multi-level digital signals to be phase modulated. In this paper, the effect of duty cycle, rise and fall times of these multi-level digital signals, on the frequency spectrum is studied. It is observed that the duty cycle variation of 10% results 30 dB increase in undesired component and the 10% increase in rise & fall times increase the power of undesired component by 12 dB. The theoretical observations of the effects are applied on the Binary Offset Carrier (BOC) modulated signals as a case study, to discuss their effects in Global Navigation Satellite Systems (GNSS).
Cyclostationary analysis of polytime coded signals for lpi radarseSAT Journals
This document discusses cyclostationary analysis of polytime coded signals for low probability of intercept (LPI) radars. It begins with an introduction to LPI radars and their modulation and detection techniques, focusing on polytime codes. It then describes cyclostationary signal processing methods like the direct frequency smoothing method (DFSM) and fast Fourier transform accumulation method (FAM) that can be used to extract parameters from polytime coded signals. The document analyzes example polytime coded signals with and without noise using these cyclostationary techniques and accurately extracts key parameters like carrier frequency, bandwidth, and code rate. It finds the FAM method has better computational efficiency than DFSM for long signals.
This document proposes using continuous wavelet transform (CWT) with a complex Morlet wavelet to detect low frequency oscillations in a power system. CWT is applied to signals measured from a two-area four-machine power system model. The results extract the frequency and damping of inter-area oscillations, which closely match those obtained from eigenvalue analysis. This demonstrates CWT as an effective technique for identifying low frequency oscillations in power systems.
A Critical Review of Time-frequency Distribution Analysis for Detection and C...IJECEIAES
This paper presents a critical review of time-frequency distributions (TFDs) analysis for detection and classification of harmonic signal. 100 unique harmonic signals comprise of numerous characteristic are detected and classified by using spectrogram, Gabor transform and S-transform. The rulebased classifier and the threshold settings of the analysis are according to the IEEE Standard 1159 2009. The best TFD for harmonic signals detection and classification is selected through performance analysis with regards to the accuracy, computational complexity and memory size that been used during the analysis.
This document discusses using wavelet transforms to analyze vibration signals from bearings for condition monitoring. It describes performing discrete wavelet transforms and wavelet packet transforms on bearing vibration data to extract statistical features like wavelet energy, entropy, and FFT magnitudes. These features are then used as inputs to an artificial neural network to classify signals as normal or faulty. The results show wavelet-based vibration monitoring can successfully detect and classify bearing faults.
Analysis and Estimation of Harmonics Using Wavelet TechniqueRadita Apriana
The paper develops an approach based on wavelet technique for the evaluation and estimation of
harmonic contents of power system waveform. The proposed algorithm decomposes the signal waveforms
into the uniform frequency sub-bands corresponding to the odd harmonic components of the signal. The
proposed implementation of algorithm determines the frequency bands of harmonics which retain both the
time and frequency relationship of the original waveforms and uses a method to suppress those
harmonics.Thewaveletalgorithm is selected to obtain compatible output bands with the harmonic groups
defined in the standards for power-supply systems. A comparative analysis will be done with the input and
the results obtained from the wavelet transform (WT) for different measuring conditions and Simulation
results are given.
Enhanced Mobile Node Tracking With Received Signal Strength in Wireless Senso...IOSR Journals
Node localization is important parameter in WSN. Node localization is required to report origin of
events which makes it one of the important challenges in WSN. Received signal strength (RSS) is used to
calculate distance between mobile node and reference node. The position of the mobile node is calculated using
multilateration algorithm (MA). Extended Kalman filter (EKF) is utilized to estimate the actual position. In this
paper, the implementation and enhancement of a tracking system based on RSS indicator with the aid of an
Extended Kalman Filter (EKF) is described and an adaptive filter is derived.
Analysis of harmonics using wavelet techniqueIJECEIAES
This paper proposes a wavelet technique to analyze harmonics in power system signals. The algorithm uses Daubechies 20 wavelet and decomposes signals into different frequency sub-bands corresponding to harmonic components. Simulation results on test signals containing various harmonic distortions show the wavelet technique can identify the time and frequency of harmonic disturbances with errors less than 1.2%. The wavelet approach provides an alternative for harmonic analysis that overcomes limitations of conventional Fourier-based methods.
This document summarizes an article from the International Journal of Electronics and Communication Engineering & Technology. The article focuses on a three-phase Clarke-maximum (Maximum p,q) trigonometrical PLL for grid connected power converters. It presents the block diagram and computer simulation model of the proposed PLL. The PLL uses Clarke and inverse Clarke transformations to extract the q and p components from the three-phase input signals. It then takes the maximum of these values to determine the error signal fed to the PI controller. This ensures there is only one equilibrium point and faster response when the initial phase difference exceeds 90 degrees compared to typical qPLL and pPLL implementations. Computer simulations validate the operation and performance of the proposed PLL structure.
Cyclostationary analysis of polytime coded signals for lpi radarseSAT Journals
This document discusses cyclostationary analysis of polytime coded signals for low probability of intercept (LPI) radars. It begins with an introduction to LPI radars and their modulation and detection techniques, focusing on polytime codes. It then describes cyclostationary signal processing methods like the direct frequency smoothing method (DFSM) and fast Fourier transform accumulation method (FAM) that can be used to extract parameters from polytime coded signals. The document analyzes example polytime coded signals with and without noise using these cyclostationary techniques and accurately extracts key parameters like carrier frequency, bandwidth, and code rate. It finds the FAM method has better computational efficiency than DFSM for long signals.
This document proposes using continuous wavelet transform (CWT) with a complex Morlet wavelet to detect low frequency oscillations in a power system. CWT is applied to signals measured from a two-area four-machine power system model. The results extract the frequency and damping of inter-area oscillations, which closely match those obtained from eigenvalue analysis. This demonstrates CWT as an effective technique for identifying low frequency oscillations in power systems.
A Critical Review of Time-frequency Distribution Analysis for Detection and C...IJECEIAES
This paper presents a critical review of time-frequency distributions (TFDs) analysis for detection and classification of harmonic signal. 100 unique harmonic signals comprise of numerous characteristic are detected and classified by using spectrogram, Gabor transform and S-transform. The rulebased classifier and the threshold settings of the analysis are according to the IEEE Standard 1159 2009. The best TFD for harmonic signals detection and classification is selected through performance analysis with regards to the accuracy, computational complexity and memory size that been used during the analysis.
This document discusses using wavelet transforms to analyze vibration signals from bearings for condition monitoring. It describes performing discrete wavelet transforms and wavelet packet transforms on bearing vibration data to extract statistical features like wavelet energy, entropy, and FFT magnitudes. These features are then used as inputs to an artificial neural network to classify signals as normal or faulty. The results show wavelet-based vibration monitoring can successfully detect and classify bearing faults.
Analysis and Estimation of Harmonics Using Wavelet TechniqueRadita Apriana
The paper develops an approach based on wavelet technique for the evaluation and estimation of
harmonic contents of power system waveform. The proposed algorithm decomposes the signal waveforms
into the uniform frequency sub-bands corresponding to the odd harmonic components of the signal. The
proposed implementation of algorithm determines the frequency bands of harmonics which retain both the
time and frequency relationship of the original waveforms and uses a method to suppress those
harmonics.Thewaveletalgorithm is selected to obtain compatible output bands with the harmonic groups
defined in the standards for power-supply systems. A comparative analysis will be done with the input and
the results obtained from the wavelet transform (WT) for different measuring conditions and Simulation
results are given.
Enhanced Mobile Node Tracking With Received Signal Strength in Wireless Senso...IOSR Journals
Node localization is important parameter in WSN. Node localization is required to report origin of
events which makes it one of the important challenges in WSN. Received signal strength (RSS) is used to
calculate distance between mobile node and reference node. The position of the mobile node is calculated using
multilateration algorithm (MA). Extended Kalman filter (EKF) is utilized to estimate the actual position. In this
paper, the implementation and enhancement of a tracking system based on RSS indicator with the aid of an
Extended Kalman Filter (EKF) is described and an adaptive filter is derived.
Analysis of harmonics using wavelet techniqueIJECEIAES
This paper proposes a wavelet technique to analyze harmonics in power system signals. The algorithm uses Daubechies 20 wavelet and decomposes signals into different frequency sub-bands corresponding to harmonic components. Simulation results on test signals containing various harmonic distortions show the wavelet technique can identify the time and frequency of harmonic disturbances with errors less than 1.2%. The wavelet approach provides an alternative for harmonic analysis that overcomes limitations of conventional Fourier-based methods.
This document summarizes an article from the International Journal of Electronics and Communication Engineering & Technology. The article focuses on a three-phase Clarke-maximum (Maximum p,q) trigonometrical PLL for grid connected power converters. It presents the block diagram and computer simulation model of the proposed PLL. The PLL uses Clarke and inverse Clarke transformations to extract the q and p components from the three-phase input signals. It then takes the maximum of these values to determine the error signal fed to the PI controller. This ensures there is only one equilibrium point and faster response when the initial phase difference exceeds 90 degrees compared to typical qPLL and pPLL implementations. Computer simulations validate the operation and performance of the proposed PLL structure.
This document presents a comparative study of monotonic and non-monotonic phase linear time-invariant (LTI) systems using an improved analytical PID controller design. It discusses using gain crossover frequency and phase margin specifications to design controllers that ensure minimum phase margin inside the desired bandwidth. For the comparative study, it uses bode stability criterion, Nyquist stability criterion, and unit step response. It presents a case study comparing the design of controllers for a buck converter system, which exhibits a non-monotonic phase response, using both monotonic and non-monotonic design techniques. The results show that treating the non-monotonic system as monotonic leads to an overvalued proportional gain and undervalued derivative gain in the PID controller.
Ensemble Empirical Mode Decomposition: An adaptive method for noise reduction IOSR Journals
This document describes ensemble empirical mode decomposition (EEMD), an adaptive method for noise reduction in signals. EEMD is an improvement over empirical mode decomposition (EMD) that can overcome the problem of mode mixing. EEMD works by decomposing the signal into intrinsic mode functions (IMFs) in the presence of added white noise, which is then averaged out. The algorithm adds white noise to the target signal multiple times, applies EMD each time, and takes the mean of the IMFs as the final result. This process separates different scales present in the signal and reduces noise. The document evaluates EEMD on electrocardiogram and other non-stationary signals, demonstrating its effectiveness in noise reduction.
Electrocardiogram Denoised Signal by Discrete Wavelet Transform and Continuou...CSCJournals
One of commonest problems in electrocardiogram (ECG) signal processing is denoising. In this paper a denoising technique based on discrete wavelet transform (DWT) has been developed. To evaluate proposed technique, we compare it to continuous wavelet transform (CWT). Performance evaluation uses parameters like mean square error (MSE) and signal to noise ratio (SNR) computations show that the proposed technique out performs the CWT.
ANALYTICAL PERFORMANCE EVALUATION OF A MIMO FSO COMMUNICATION SYSTEM WITH DIR...optljjournal
MIMO FSO correspondence is examined as of late to build up a hearty correspondence connects within the sight of atmospheric turbulence. In this paper an analytical approach is developed to assess the impact of atmospheric turbulence on BER performance of a MIMO FSO communication system with Q-ary Pulse Position Modulation (QPPM). Examination is exhibited to discover flag to clamor proportion at the yield of an immediate location collector with optical power modulator under strong turbulent condition which is modeled as gamma-gamma distribution. The outcomes demonstrate that the BER performance is emphatically debased because of the impact of atmospheric turbulence. In any case, the execution can be enhanced by expanding the quantity of transmitters, beneficiaries and request of Q in PPM. Results demonstrate that the FSO MIMO framework with M=8, N=4 Q=4 gives the 22 dB improvement at BER of 10-9 .
Comparative analysis on an exponential form of pulse with an integer and non-...IJERA Editor
This document presents a comparative analysis of using exponential pulses with integer and non-integer exponents for pulse compression in radar systems. Pulse compression aims to achieve better range and velocity resolution by extending the frequency spectrum of transmitted pulses while keeping pulse duration constant. The document simulates exponential pulses with different exponents in the time and frequency domains. It analyzes parameters like time-bandwidth product, peak sidelobe level, and main lobe width from the matched filter output and ambiguity function. The results show that differentiated non-integer exponential pulses modulated with a carrier signal provide better pulse compression performance compared to other pulse forms.
Degradation of ICI in OFDM Communication System by Analyzing I/Q Imbalance an...IRJET Journal
This document analyzes the degradation of orthogonal frequency division multiplexing (OFDM) communication systems due to intercarrier interference (ICI) caused by I/Q imbalance and timing jitter. It presents an analytical model to study the interaction between timing jitter and I/Q imbalance and the resulting additional ICI terms. Simulation results show that timing jitter introduces more ICI than I/Q imbalance. For larger timing jitter values, its impact on ICI dominates over I/Q imbalance, while I/Q imbalance dominates when timing jitter is relatively small. The interaction between timing jitter and I/Q imbalance produces a negligible increase in ICI in all cases.
Analysis of cyclic prefix length effect on ISI limitation in OFDM system over...IJECEIAES
In this work, the influence of the cyclic prefix on the performance of the OFDM system is studied. We worked out an OFDM transceiver using a 16 QAM modulation scheme, a comparison of the BER for various lengths of the cyclic prefix has been achieved, and the influence of the noise introduced in the channel has been highlighted, for both a Gaussian and Rayleigh noise. The simulation was carried out on MATLAB where the curves of the BER for various lengths of the cyclic prefix are given and compared. We also adopted as a metric the QAM constellation to show the dispersion of the carriers as a consequence of the transmission channel, the mitigation of this effect by the CP is noticeable.
This document proposes and analyzes a system for generating continuous variable quantum codes using nonlinear microring resonators (NMRRs). Optical solitons or Gaussian pulses propagating in the NMRRs induce chaotic behavior and generate large bandwidth signals suitable for high channel capacity quantum communication. The system uses multiple cascaded NMRRs along with a polarization controller and beam splitter to generate distinguished up and down optical soliton link pulses. Simulations show the system can obtain specific frequency bands and wavelengths for quantum key distribution applications by controlling the NMRR parameters.
Comparison and analysis of orthogonal and biorthogonal wavelets for ecg compr...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
3.[14 28]space vector based dual zero-vector random centered distribution pwm...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
11.space vector based dual zero vector random centered distribution pwm algor...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
Comparative Analysis of Different Wavelet Functions using Modified Adaptive F...IJERA Editor
The traditional method of wavelet denoising is inefficient in removing the overlap noise between noisy signal
and noise, due to which a modified adaptive filtering based on wavelet transform method is introduced. The
method used in this paper filters out the noise on the basis of wavelet denoising using different wavelet
functions. The simulation results indicate the Signal to Noise ratio (SNR), Mean Square Error (MSE) and signal
error power spectral density comparison plot between different wavelet functions. These comparison results
verified that Daubechies is more efficient than other wavelet functions in filtering out noise in all perspectives.
An Accurate Classification Method of Harmonic Signals in Power Distribution S...TELKOMNIKA JOURNAL
This document presents a method for classifying harmonic signals in power distribution systems using S-transform (ST). ST represents signals in the time-frequency domain and is used to estimate spectral parameters for classification. A rule-based classifier classifies 100 unique signals according to IEEE standards. The accuracy of signal parameter estimation using ST is high, with mean absolute percentage errors below 0.06. ST also achieves 100% correct classification of harmonic versus inter-harmonic signals in testing. The proposed ST-based classification method accurately detects and classifies harmonic signals in power distribution systems.
Spectrum analysis characterizes the frequency content of signals. Power spectral estimation methods obtain an approximate estimate of the power spectral density of random processes. Non-parametric power spectral estimation does not assume any data generation process or model, and involves dividing a signal into segments and averaging the periodograms of each segment to reduce variance. Common non-parametric methods include Bartlett's method, Welch's method, and Blackman-Tukey method.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
1) The document discusses power spectrum estimation methods for digital signal processing.
2) It describes five common non-parametric power spectrum estimation techniques: periodogram method, modified periodogram method, Bartlett's method, Welch's method, and Blackman-Tukey method.
3) Each method has different tradeoffs between frequency resolution, variance, and bias that make some techniques better for certain applications like feature extraction.
Tuning PID Controller Parameters for Load Frequency Control Considering Syste...IJERA Editor
In this paper, parameters of PID controller and bias coefficient for Load Frequency Control (LFC) are designed using a new approach. In the proposed method, the power system uncertainties and nonlinear limitations of governors and turbines ,i.e. Valve Speed Limit (VSL)and Generation Rate Constraint (GRC), are taken into account in designing. Variations of uncertain parameters are considered between -40% and +40% of nominal values with 5% step .In order to design the proposed PID controller ,a new objective function is defined. MATLAB codes are developed for GA based PID controller tuning, the results of which are used to study the system step response. All these are through in Simulink based background.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
A new approach for Tuning of PID Load Frequency Controller of an Interconnect...Editor IJMTER
This document describes a new approach for tuning PID load frequency controllers in an interconnected power system consisting of three areas. It begins by describing the structure and components of PID controllers used for load frequency control. It then provides details on the three-area power system model consisting of different turbine types in each area. The document then explains the Ziegler-Nichols and Pessen Integral Rule methods for tuning the PID controllers in each area. The controller gains for each plant in the system are calculated using both classical and proposed PID tuning methods. Simulation results show the proposed controller provides better dynamic performance than the classical PID controller.
This document contains 20 questions about load-frequency control in single-area power systems. The questions cover topics like the function of load frequency control, how real power is controlled, definitions of terms like fly ball governor, inertia constant, area control error, per unit droop, tie line bias control, and the basic role of automatic load frequency control. It also asks about control areas, tie line power deviation equations, static and dynamic responses, assumptions in dynamic response modeling, speed regulation, automatic frequency response control, block diagrams, the need for speed changers, the importance of load frequency control, and definitions of time constant and frequency deviation.
1. Load frequency control (LFC) is used to maintain the frequency and power flow between interconnected power systems within specified limits.
2. LFC is important for reliable electric power supply with good quality. Proportional-integral control is one strategy that has been proposed to improve LFC performance.
3. In this thesis, a proportional-integral controller technique is employed to design an efficient load frequency controller for a two-area interconnected hydro power system. The design aims to achieve zero steady-state error and ensure good transient response to disturbances while maintaining closed-loop stability.
This document presents a comparative study of monotonic and non-monotonic phase linear time-invariant (LTI) systems using an improved analytical PID controller design. It discusses using gain crossover frequency and phase margin specifications to design controllers that ensure minimum phase margin inside the desired bandwidth. For the comparative study, it uses bode stability criterion, Nyquist stability criterion, and unit step response. It presents a case study comparing the design of controllers for a buck converter system, which exhibits a non-monotonic phase response, using both monotonic and non-monotonic design techniques. The results show that treating the non-monotonic system as monotonic leads to an overvalued proportional gain and undervalued derivative gain in the PID controller.
Ensemble Empirical Mode Decomposition: An adaptive method for noise reduction IOSR Journals
This document describes ensemble empirical mode decomposition (EEMD), an adaptive method for noise reduction in signals. EEMD is an improvement over empirical mode decomposition (EMD) that can overcome the problem of mode mixing. EEMD works by decomposing the signal into intrinsic mode functions (IMFs) in the presence of added white noise, which is then averaged out. The algorithm adds white noise to the target signal multiple times, applies EMD each time, and takes the mean of the IMFs as the final result. This process separates different scales present in the signal and reduces noise. The document evaluates EEMD on electrocardiogram and other non-stationary signals, demonstrating its effectiveness in noise reduction.
Electrocardiogram Denoised Signal by Discrete Wavelet Transform and Continuou...CSCJournals
One of commonest problems in electrocardiogram (ECG) signal processing is denoising. In this paper a denoising technique based on discrete wavelet transform (DWT) has been developed. To evaluate proposed technique, we compare it to continuous wavelet transform (CWT). Performance evaluation uses parameters like mean square error (MSE) and signal to noise ratio (SNR) computations show that the proposed technique out performs the CWT.
ANALYTICAL PERFORMANCE EVALUATION OF A MIMO FSO COMMUNICATION SYSTEM WITH DIR...optljjournal
MIMO FSO correspondence is examined as of late to build up a hearty correspondence connects within the sight of atmospheric turbulence. In this paper an analytical approach is developed to assess the impact of atmospheric turbulence on BER performance of a MIMO FSO communication system with Q-ary Pulse Position Modulation (QPPM). Examination is exhibited to discover flag to clamor proportion at the yield of an immediate location collector with optical power modulator under strong turbulent condition which is modeled as gamma-gamma distribution. The outcomes demonstrate that the BER performance is emphatically debased because of the impact of atmospheric turbulence. In any case, the execution can be enhanced by expanding the quantity of transmitters, beneficiaries and request of Q in PPM. Results demonstrate that the FSO MIMO framework with M=8, N=4 Q=4 gives the 22 dB improvement at BER of 10-9 .
Comparative analysis on an exponential form of pulse with an integer and non-...IJERA Editor
This document presents a comparative analysis of using exponential pulses with integer and non-integer exponents for pulse compression in radar systems. Pulse compression aims to achieve better range and velocity resolution by extending the frequency spectrum of transmitted pulses while keeping pulse duration constant. The document simulates exponential pulses with different exponents in the time and frequency domains. It analyzes parameters like time-bandwidth product, peak sidelobe level, and main lobe width from the matched filter output and ambiguity function. The results show that differentiated non-integer exponential pulses modulated with a carrier signal provide better pulse compression performance compared to other pulse forms.
Degradation of ICI in OFDM Communication System by Analyzing I/Q Imbalance an...IRJET Journal
This document analyzes the degradation of orthogonal frequency division multiplexing (OFDM) communication systems due to intercarrier interference (ICI) caused by I/Q imbalance and timing jitter. It presents an analytical model to study the interaction between timing jitter and I/Q imbalance and the resulting additional ICI terms. Simulation results show that timing jitter introduces more ICI than I/Q imbalance. For larger timing jitter values, its impact on ICI dominates over I/Q imbalance, while I/Q imbalance dominates when timing jitter is relatively small. The interaction between timing jitter and I/Q imbalance produces a negligible increase in ICI in all cases.
Analysis of cyclic prefix length effect on ISI limitation in OFDM system over...IJECEIAES
In this work, the influence of the cyclic prefix on the performance of the OFDM system is studied. We worked out an OFDM transceiver using a 16 QAM modulation scheme, a comparison of the BER for various lengths of the cyclic prefix has been achieved, and the influence of the noise introduced in the channel has been highlighted, for both a Gaussian and Rayleigh noise. The simulation was carried out on MATLAB where the curves of the BER for various lengths of the cyclic prefix are given and compared. We also adopted as a metric the QAM constellation to show the dispersion of the carriers as a consequence of the transmission channel, the mitigation of this effect by the CP is noticeable.
This document proposes and analyzes a system for generating continuous variable quantum codes using nonlinear microring resonators (NMRRs). Optical solitons or Gaussian pulses propagating in the NMRRs induce chaotic behavior and generate large bandwidth signals suitable for high channel capacity quantum communication. The system uses multiple cascaded NMRRs along with a polarization controller and beam splitter to generate distinguished up and down optical soliton link pulses. Simulations show the system can obtain specific frequency bands and wavelengths for quantum key distribution applications by controlling the NMRR parameters.
Comparison and analysis of orthogonal and biorthogonal wavelets for ecg compr...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
3.[14 28]space vector based dual zero-vector random centered distribution pwm...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
11.space vector based dual zero vector random centered distribution pwm algor...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
Comparative Analysis of Different Wavelet Functions using Modified Adaptive F...IJERA Editor
The traditional method of wavelet denoising is inefficient in removing the overlap noise between noisy signal
and noise, due to which a modified adaptive filtering based on wavelet transform method is introduced. The
method used in this paper filters out the noise on the basis of wavelet denoising using different wavelet
functions. The simulation results indicate the Signal to Noise ratio (SNR), Mean Square Error (MSE) and signal
error power spectral density comparison plot between different wavelet functions. These comparison results
verified that Daubechies is more efficient than other wavelet functions in filtering out noise in all perspectives.
An Accurate Classification Method of Harmonic Signals in Power Distribution S...TELKOMNIKA JOURNAL
This document presents a method for classifying harmonic signals in power distribution systems using S-transform (ST). ST represents signals in the time-frequency domain and is used to estimate spectral parameters for classification. A rule-based classifier classifies 100 unique signals according to IEEE standards. The accuracy of signal parameter estimation using ST is high, with mean absolute percentage errors below 0.06. ST also achieves 100% correct classification of harmonic versus inter-harmonic signals in testing. The proposed ST-based classification method accurately detects and classifies harmonic signals in power distribution systems.
Spectrum analysis characterizes the frequency content of signals. Power spectral estimation methods obtain an approximate estimate of the power spectral density of random processes. Non-parametric power spectral estimation does not assume any data generation process or model, and involves dividing a signal into segments and averaging the periodograms of each segment to reduce variance. Common non-parametric methods include Bartlett's method, Welch's method, and Blackman-Tukey method.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
1) The document discusses power spectrum estimation methods for digital signal processing.
2) It describes five common non-parametric power spectrum estimation techniques: periodogram method, modified periodogram method, Bartlett's method, Welch's method, and Blackman-Tukey method.
3) Each method has different tradeoffs between frequency resolution, variance, and bias that make some techniques better for certain applications like feature extraction.
Tuning PID Controller Parameters for Load Frequency Control Considering Syste...IJERA Editor
In this paper, parameters of PID controller and bias coefficient for Load Frequency Control (LFC) are designed using a new approach. In the proposed method, the power system uncertainties and nonlinear limitations of governors and turbines ,i.e. Valve Speed Limit (VSL)and Generation Rate Constraint (GRC), are taken into account in designing. Variations of uncertain parameters are considered between -40% and +40% of nominal values with 5% step .In order to design the proposed PID controller ,a new objective function is defined. MATLAB codes are developed for GA based PID controller tuning, the results of which are used to study the system step response. All these are through in Simulink based background.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
A new approach for Tuning of PID Load Frequency Controller of an Interconnect...Editor IJMTER
This document describes a new approach for tuning PID load frequency controllers in an interconnected power system consisting of three areas. It begins by describing the structure and components of PID controllers used for load frequency control. It then provides details on the three-area power system model consisting of different turbine types in each area. The document then explains the Ziegler-Nichols and Pessen Integral Rule methods for tuning the PID controllers in each area. The controller gains for each plant in the system are calculated using both classical and proposed PID tuning methods. Simulation results show the proposed controller provides better dynamic performance than the classical PID controller.
This document contains 20 questions about load-frequency control in single-area power systems. The questions cover topics like the function of load frequency control, how real power is controlled, definitions of terms like fly ball governor, inertia constant, area control error, per unit droop, tie line bias control, and the basic role of automatic load frequency control. It also asks about control areas, tie line power deviation equations, static and dynamic responses, assumptions in dynamic response modeling, speed regulation, automatic frequency response control, block diagrams, the need for speed changers, the importance of load frequency control, and definitions of time constant and frequency deviation.
1. Load frequency control (LFC) is used to maintain the frequency and power flow between interconnected power systems within specified limits.
2. LFC is important for reliable electric power supply with good quality. Proportional-integral control is one strategy that has been proposed to improve LFC performance.
3. In this thesis, a proportional-integral controller technique is employed to design an efficient load frequency controller for a two-area interconnected hydro power system. The design aims to achieve zero steady-state error and ensure good transient response to disturbances while maintaining closed-loop stability.
This document discusses constraints and load flow analysis in power systems. It outlines four key constraints: active power constraint, reactive power constraint, voltage magnitude constraint, and load angle constraint. It also describes load flow analysis as a balanced mechanism between demand and generation under incremental loading. Load flow analysis is important for the safe and future operation of power systems. The document further discusses bus classification, basic power flow conditions including the proportional relationships between reactive power and voltage and active power and load angle. It also covers the development of the Y-bus matrix considering line resistances and inductances alone and then including line capacitances.
This document presents an overview of economic load dispatch in power systems. It discusses the objectives of economic dispatch as generating required power at minimum cost. It describes different constraints like generator limits, transmission limits and voltage limits that need to be considered. It explains the operating costs of thermal plants using heat rate and fuel cost curves. It provides formulations for economic dispatch neglecting and including transmission losses. The document uses examples to illustrate the iterative method used to solve economic dispatch problems.
The document discusses the components and characteristics of a PID controller. A PID controller uses proportional, integral and derivative actions to control process variables.
The proportional action depends on current error. The integral action depends on accumulated past errors to eliminate steady-state error over time. The derivative action predicts future errors based on the current rate of change to improve stability and reduce overshoot.
Together these three actions allow a PID controller to control processes very well without overshoot or undershoot by setting the optimal P, I, and D values for the specific application.
Messages addressed to specific users can be decrypted by Key Generation Centre (KGC) by generating their private keys. Data owner wants the data to be delivered only to specified user and not to unauthorized person that is the data owner makes their private data accessible only to authorized person. We propose attribute based encryption and escrow problem which means written agreement delivered to a third party to overcome this problem. Attribute based Encryption (ABE) is a type of public-key encryption in which the private key of a user and the cipher text are dependent upon attributes. It is a promising cryptographic approach.
Analysis and Weight Optimization of Split Dish Reactor Using Thermo-Structura...IJERA Editor
A vertical split dish reactor with leg supports is modeled using ansys workbench. Thereafter, external loads, such as self –weight, internal pressure and temperature are applied to the model. Pressure and temperature has been continuously a concern which may lead to structural failure if the resulting stresses are severe and excessive. It is a significant study which requires in-depth investigation to understand the structural characteristics. This paper presents and focuses on some Finite Element (FE) analysis of a split dish reactor will be carried out and maximum stresses in the structure will be determined.
This document presents a low-cost method for electromagnetic signal spectral analysis and direction finding using a two-element time-modulated antenna array and multiple signal classification (MUSIC) algorithms. It describes a prototype array constructed using quarter-wave monopoles as antenna elements switched using PIN diodes. Measurements show the array output is phase modulated depending on signal arrival angle, producing a directional pattern at the carrier frequency and null at the first harmonic. MUSIC algorithms are applied to estimate signal directions from the received signals. The method provides a low-cost alternative to conventional direction finding techniques with potential applications in wireless communications and homeland security.
Visual Product Identification for BlindIJERA Editor
This project is developed to make the life of blind people easy. This is a camera based system to scan the
barcode behind the image and read the description of the product with the help of Id stored in the barcode. This
is very beneficial in case of finding out the description of packaged goods to the blind people and thus helping
them in deciding to purchase a product or not especially which are packaged. This is because it becomes very
difficult for the blind people to distinguish between the packaged goods. In order to use this system, all the user
needs to do is capture the image on the product in the mobile phone which then resolves the barcode which
means it scans the image to find out the Id stored. Thus this application really benefits blind and visually
impaired people and thus making their work of identifying products easy. This is very easy to use and affordable
as it requires a scanner to scan the barcode and a camera phone to take the picture of the image containing the
barcode. This is now easy to implement as most of the mobile phones today have the required resolution in order
to scan the barcode to identify the Id stored in it and read out the product description. This project can be
implemented in any shopping mall, supermarket, Book stores, Medical stores etc.
Real Time Implementation Of Face Recognition SystemIJERA Editor
This paper proposes face recognition method using PCA for real time implementation. Nowadays security is
gaining importance as it is becoming necessary for people to keep passwords in their mind and carry cards. Such
implementations however, are becoming less secure and practical, also is becoming more problematic thus
leading to an increasing interest in techniques related to biometrics systems. Face recognition system is amongst
important subjects in biometrics systems. This system is very useful for security in particular and has been
widely used and developed in many countries. This study aims to achieve face recognition successfully by
detecting human face in real time, based on Principal Component Analysis (PCA) algorithm.
Voice Activity Detector of Wake-Up-Word Speech Recognition System Design on FPGAIJERA Editor
A typical speech recognition system is push-to-talk operated that requires activation. However for those who use hands-busy applications, movement may by restricted or impossible. One alternative is to use Speech-Only Interface. The proposed method that is called Wake-Up-Word Speech Recognition (WUW-SR) that utilizes speech only interface. A WUW-SR system would allow the user to activate systems (Cell phone, Computer, etc.) with only speech commands instead of manual activation. The trend in WUW-SR hardware design is towards implementing a complete system on a single chip intended for various applications. This paper presents an experimental FPGA design and implementation of a novel architecture of a real time feature extraction processor that includes: Voice Activity Detector (VAD), and features extraction, MFCC, LPC, and ENH_MFCC. In the WUW-SR system, the recognizer front-end with VAD is located at the terminal which is typically connected over a data network(e.g., server)for remote back-end recognition. VAD is responsible for segmenting the signal into speech-like and non-speech-like segments. For any given frame VAD reports one of two possible states: VAD_ON or VAD_OFF. The back-end is then responsible to score the features that are being segmented during VAD_ON stage. The most important characteristic of the presented design is that it should guarantee virtually 100% correct rejection for non-WUW (out of vocabulary words - OOV) while maintaining correct acceptance rate of 99.9% or higher (in vocabulary words - INV). This requirement sets apart WUW-SR from other speech recognition tasks because no existing system can guarantee 100% reliability by any measure.
Research onidentify stadia of interchange exit ramp in mountainous urban freewayIJERA Editor
Theidentify stadia of interchange exit ramp hasgreat influence on capacity and safety levels of urbanexpressway,combining with car psychological theory and driverscharacteristics,based on design speed and driver's reaction time, driversoperating characteristics and the cause of the accident on interchange exit ramp was analyzed and the identify stadia threshold under different design speedwas determined. The resultindicates that: the requirements of specification for identify stadia has some limitations, it should be modified appropriately.
Allocation Strategies of Virtual Resources in Cloud-Computing NetworksIJERA Editor
In distributed computing, Cloud computing facilitates pay per model as per user demand and requirement.
Collection of virtual machines including both computational and storage resources will form the Cloud. In
Cloud computing, the main objective is to provide efficient access to remote and geographically distributed
resources. Cloud faces many challenges, one of them is scheduling/allocation problem. Scheduling refers to a
set of policies to control the order of work to be performed by a computer system. A good scheduler adapts its
allocation strategy according to the changing environment and the type of task. In this paper we will see FCFS,
Round Robin scheduling in addition to Linear Integer Programming an approach of resource allocation.
Ultrasonic and Volumetric Investigations of -Butyrolactone with Aliphatic Al...IJERA Editor
Densities () and speeds of sound (u) have been determined for the binary liquid mixtures of -butyrolactone (GBL) with 1-propanol (1-Pro), 2-propanol (2-Pro), 1-butanol (1-But) and 2-butanol (2-But) at 303.15, 308.15, and 313.15 K and entire composition range. From the experimental results, the excess molar volume (VE), and deviation in isentropic compressibility (s) were calculated. The computed properties have been fitted to a Redlich-Kister type polynomial equation to derive binary coefficients and standard deviations.
This document summarizes research on neuromorphic silicon neurons and synapses. It discusses how analog VLSI circuits can mimic the behavior of biological neurons and synapses. Specifically, it describes the implementation of integrate-and-fire neuron models using axon-hillock circuits and voltage amplifier circuits. It also briefly discusses non-plastic and plastic silicon synapses. The goal is to develop biologically inspired hardware systems using very large scale integrated circuits to model the basic computational units of the nervous system.
Evaluation of Post-liquefaction Reconsolidation Settlement based on Standard ...IJERA Editor
This paper aims to deal with the evaluation of post-liquefaction reconsolidation settlement of soils using
Standard Penetration Tests data. Evaluation of the settlement is conducted at Semani site in Albania, according
to the SPT method presented by Idriss and Boulanger 2008, 2010. The input data for the SPT method are SPT
borings with depth, moment magnitude of the earthquake, maximum surface acceleration during earthquake,
depth to ground water table, and the unit weights of the soils. The calculation procedure includes estimation of
the cyclic stress ratio induced in the soil by the earthquake, cyclic resistance ratio that will cause liquefaction,
factor of safety against the triggering of liquefaction, post-liquefaction strain and of the post-liquefaction
reconsolidation settlement. The results of the calculations utilizing this procedure are shown in graphs and are
compared to those based on CPT method. It is observed that the calculated post-liquefaction reconsolidation
settlements based on SPT method are less than ones calculated based on CPT method.
Wavelet Based Fault Detection, Classification in Transmission System with TCS...IJERA Editor
This paper presents simulation results of the application of distance relays for the protection of transmission systems employing flexible alternating current transmission controllers such as Thyristor Controlled Series Capacitor (TCSC). The complete digital simulation of TCSC within a transmission system is performed in the MATLAB/Simulink environment using the Power System Block set (PSB). This paper presents an efficient method based on wavelet transforms both fault detection and classification which is almost independent of fault impedance, fault location and fault inception angle of transmission line fault currents with FACTS controllers.
Digital signal processing techniques for lti fiber impairment compensationeSAT Journals
Abstract Coherent detection is one of the active research areas for the development of high speed, high spectral efficient optical communication network. Digital signal processing is the important technique for compensating the fiber transmission impairments because of number of advantages such as signal can be amplified, delayed, splitted and manipulated without degrading the signal quality. This paper presents DSP compensation algorithms for linear time invariant (LTI) impairment such as chromatic dispersion (CD) and polarization mode dispersion (PMD) in optical fiber communication. We presented a mathematical framework for compensation of LTI fiber impairments. This paper also focuses the different compensation methods both in time and frequency domain for chromatic dispersion compensation. These DSP techniques confirm that coherent detection with high data rates will become feasible in future for compensating transmission impairments. Keywords: Coherent Detection, Chromatic Dispersion, Polarization Mode Dispersion
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
For ease of analog or digital information transmission and reception, modulation is the foremost important technique. In the present project, we’ll discuss about different modulation scheme in digital mode done by operating a switch/ key by the digital data. As we know, by modifying basic three parameters of the carrier signal, three basic modulation schemes can be obtained; generation and detection of these three modulations are discussed and compared with respect to probability of error or bit error rate (BER).
Cryptography Scheme of an Optical Switching System Using Pico/Femto Second So...University of Malaya (UM)
We propose a system of microring resonators (MRRs) incorporating with an add/drop filter system. Optical soliton can be simulated and used to generate entangled photon, applicable in single and multiple optical switching. Chaotic signals can be generated via the MRRs system. Therefore continuous spatial and temporal signals are generated spreading over the spectrum. Polarized photons are formed incorporating the
polarization control unit into the MRRs, which allows different time slot entangled photons to be randomly formed. Results show the single soliton pulse of 0.7 ps where the multi soliton pulse with FSR and FWHM of 0.6 ns and 20 ps are generated using the add/drop filter system. Here Ultra-short single soliton pulse with FWHM=42 fs can be simulated. These pulses are providing required communication signals to generate pair of polarization entangled photons among different time frame where the polarization control unit and polarizer beam splitter (PBS) are connected to the ring resonator system.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
A Simple Design to Mitigate Problems of Conventional Digital Phase Locked LoopCSCJournals
This paper presents a method which can estimate frequency, phase and power of received signal corrupted with additive white Gaussian noise (AWGN) in large frequency offset environment. Proposed method consists of two loops, each loop is similar to a phase–locked loop (PLL) structure. The proposed structure solves the problems of conventional PLL such as limited estimation range, long settling time, overshoot, high frequency ripples and instability. Traditional inability of PLL to synchronize signals with large frequency offset is also removed in this method. Furthermore, proposed architecture along with providing stability, ensures fast tracking of any changes in input frequency. Proposed method is also implemented using field programmable gate array (FPGA), it consumes 201 mW and works at 197 MHz.
A Utilisation of Improved Gabor Transform for Harmonic Signals Detection and ...IJECEIAES
This paper presents a utilization of improved Gabor transform for harmonic signals detection and classification analysis in power distribution system. The Gabor transform is one of time frequency distribution technique with a capability of representing signals in jointly time-frequency domain and known as time frequency representation (TFR). The estimation of spectral information can be obtained from TFR in order to identify the characteristics of the signals. The detection and classification of harmonic signals for 100 unique signals with numerous characteristic of harmonics with support of rule-based classifier and threshold setting that been referred to IEEE standard 1159 2009. The accuracy of proposed method is determined by using MAPE and the outcome demonstrate that the method gives high accuracy of harmonic signals classification. Additionally, Gabor transform also gives 100 percent correct classification of harmonic signals. It is verified that the proposed method is accurate and cost efficient in detecting and classifying harmonic signals in distribution system.
A Utilisation of Improved Gabor Transform for Harmonic Signals Detection and ...Yayah Zakaria
his paper presents a utilization of improved Gabor transform for harmonic signals detection and classification analysis in power distribution system. The Gabor transform is one of time frequency distribution technique with a capability of representing signals in jointly time-frequency domain and known as time frequency representation (TFR). The estimation of spectral
information can be obtained from TFR in order to identify the characteristics of the signals. The detection and classification of harmonic signals for 10 unique signals with numerous characteristic of harmonics with support of rule-based classifier and threshold setting that been referred to IEEE standard 1159 2009. The accuracy of proposed method is determined by using MAPE and the outcome demonstrate that the method gives high accuracy of harmonic signals classification. Additionally, Gabor transform also gives 100 percent correct classification of harmonic signals. It is verified that the proposed method is accurate and cost efficient in detecting and classifying harmonic signals in distribution system.
This document discusses techniques for mitigating conducted electromagnetic interference (EMI) in DC-DC converter topologies. It analyzes three random pulse width modulation techniques - Randomized Trailing Edge with Randomized Pulse Width Modulation, Randomized Trailing Edge with Randomized Pulse Position Modulation, and Constant Trailing Edge with Randomized Duty Ratio and Randomized Pulse Position Modulation with Fixed Carrier Frequency. Analytical derivations of the power spectral density are presented for each technique. The techniques aim to spread harmonic power in the frequency domain and reduce electromagnetic interference without using additional hardware components.
Software PLL for PLI synchronization, design, modeling and simulation , sozopoldpdobrev
Power-line interference is a common disturbing
factor in almost all two-electrode biosignal acquisition
applications. Many filtering procedures for mains
interference elimination are available, but all of them are
maximally effective when the filter notches are positioned
exactly at the power-line harmonics, i. e. when the sampling rate is synchronous with the power-line frequency. Moreover, various lock-in techniques, su ch as automatic common mode input impedance balance, require precise in-phase and quadrature phase references, synchronous with the power-line interference. This paper describes in depth a design procedure of software PLL, generating synchronous reference to the common mode power-line interference, and achieved from its analog prototype using s to z backward difference transformation. The main advantage of th e presented
approach is that the synchronization is done in software, so it has no production cost. The presented PLL is intended for use in ECG signal processing, but it can be used after easy adaptation in various digital si gnal processing applications, where frequency synchronization is needed.
The application wavelet transform algorithm in testing adc effective number o...ijcsit
In evaluating Analog to Digital Convertors, many parameters are checked for performance and error rate.
One of these parameters is the device Effective Number of Bits. In classical testing of Effective Number of
Bits, testing is based on signal to noise components ratio (SNR), whose coefficients are driven via
frequency domain (Fourier Transform) of ADC’s output signal. Such a technique is extremely sensitive to
noise and require large number of data samples. That is, longer and more complex testing process as the
device under test increases in resolutions. Meanwhile, a new time – frequency domain approach (known as
Wavelet transform) is proposed to measure and analyze Analog-to-Digital Converters parameter of
Effective Number of Bits with less complexity and fewer data samples.
Packets Wavelets and Stockwell Transform Analysis of Femoral Doppler Ultrasou...IJECEIAES
Ultrasonic Doppler signals are widely used in the detection of cardiovascular pathologies or the evaluation of the degree of stenosis in the femoral arteries. The presence of stenosis can be indicated by disturbing the blood flow in the femoral arteries, causing spectral broadening of the Doppler signal. To analyze these types of signals and determine stenosis index, a number of time-frequency methods have been developed, such as the short-time Fourier transform, the continuous wavelets transform, the wavelet packet transform, and the S-transform
HEATED WIND PARTICLE’S BEHAVIOURAL STUDY BY THE CONTINUOUS WAVELET TRANSFORM ...cscpconf
Nowadays Continuous Wavelet Transform (CWT) as well as Fractal analysis is generally used for the Signal and Image processing application purpose. Our current work extends the field of application in case of CWT as well as Fractal analysis by applying it in case of the agitated wind particle’s behavioral study. In this current work in case of the agitated wind particle, we have mathematically showed that the wind particle’s movement exhibits the “Uncorrelated” characteristics during the convectional flow of it. It is also demonstrated here by the Continuous Wavelet Transform (CWT) as well as the Fractal analysis with matlab 7.12 version
Design and Implementation of Low Ripple Low Power Digital Phase-Locked LoopCSCJournals
We propose a phase-locked loop (PLL) architecture, which reduces the double frequency ripple without increasing the order of loop filter. Proposed architecture uses quadrature numerically–controlled oscillator (NCO) to provide two output signals with phase difference of π/2. One of them is subtracted from the input signal before multiplying with the other output of NCO. The system also provides stability in case the input signal has noise in amplitude or phase. The proposed structure is implemented using field programmable gate array (FPGA), which dissipates 15.44mw and works at clock frequency of 155.8 MHz.
Decimal convertor application for optical wireless communication by generatin...University of Malaya (UM)
This document proposes a system to generate dark and bright optical soliton pulses for use in secure wireless communication networks. It uses microring resonators to generate multiple wavelengths of optical pulses. These pulses are then sent through a polarization control system to encode them as quantum codes using dark and bright solitons. The soliton pulses can then be converted to digital logic codes using a decimal converter and transmitted securely over wireless networks. The system is able to generate multi-wavelength soliton pulses ranging from 1.55 to 1.56 micrometers with a full width at half maximum of 10 picometers and a free spectral range of 600 picometers.
Decimal Convertor Application for Optical Wireless Communication by Generatin...University of Malaya (UM)
Two systems consist of microring resonators (MRRs) and an add/drop filter are used to generate signals as localized multi wavelengths. Quantum dense encoding
can be performed by output signals of selected wavelengths incorporated to a polarization control system. Therefore dark and bright optical soliton pulses
with different time slot are generated. They can be converted into digital logic quantum codes using a decimal convertor system propagating along a wireless networks. Results show that multi soliton wavelength, ranged from 1.55 m to 1.56 m with FWHM and FSR of 10 pm and 600 pm can be generated respectively. Keywords- Micro Ring Resonator, Quantum Dense Coding (QDC), Wireless network communication system.
Analysis of s band substrate integrated waveguide power divider, circulator a...IJCSEA Journal
The Substrate Integrated Waveguide (SIW) technology is a very promising technique with which we can
take the advantages of both waveguides and planar transmission lines. Therefore, in [2.1-3] GHz band
various microwave components and devices have been designed successfully using Ansoft HFSS software.
We then proceeded to the realization of the coupler and then made measurements of the frequency
response in the range [2.1-3] GHz using a network analyzer. Thus, results of this modeling are presented,
discussed and allow to integrate these devices in planar circuits.
Ber performance of ofdm with discrete wavelet transform for time dispersive c...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Similar to Load Frequency Control, Integral control, Fuzzy Logic. (20)
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
ML Based Model for NIDS MSc Updated Presentation.v2.pptx
Load Frequency Control, Integral control, Fuzzy Logic.
1. Rahul Gupta et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 5, Issue 6, ( Part -1) June 2015, pp.65-69
www.ijera.com 65 | P a g e
A Systematic Approach to Improve BOC Power Spectrum for
GNSS
Rahul Gupta, Alak Banik, Dipti R Patel, Sohan M Patel, TVS Ram
Optical & Digital Communications Group/SATCOM & Navigation Payload Area
Space Applications Centre, Indian Space Research Organization, Ahmedabad, India
ABSTRACT
An analysis of digital Phase-modulated signals is performed based on frequency spectrum which consists of a
continuous and a number of discrete components at multiples of clock frequencies. The analysis shows that
these components depend on the pulse shape function of multi-level digital signals to be phase modulated. In
this paper, the effect of duty cycle, rise and fall times of these multi-level digital signals, on the frequency
spectrum is studied. It is observed that the duty cycle variation of 10% results 30 dB increase in undesired
component and the 10% increase in rise & fall times increase the power of undesired component by 12 dB. The
theoretical observations of the effects are applied on the Binary Offset Carrier (BOC) modulated signals as a
case study, to discuss their effects in Global Navigation Satellite Systems (GNSS).
Keywords - PSK, BOC, GNSS, Pulse duration, Rise time, Fall time
I. INTRODUCTION
In current digital technology era, the information
is mostly transferred using digital phase-modulated
signals [1], considering the ease in demodulator
design and simple detection techniques using
maximum-likelihood [2]. The digital phase-
modulated signals are allowed to have multiple levels
[3] instead of just two levels (0 and 1). These multi-
level signals are assumed to be represented by
independent non-overlapping pulses. These pulses
can be characterized by different pulse shapes and
with the different occurrence probabilities for
correlation with spectrum of pulse shapes. The
spectral contents other than desired in band are
difficult to remove by filter of complex digital taps
[4]. In this paper, we discuss a simplified solution by
appropriate analysis of effects of pulse shape
followed by demonstrating it on practical circuit with
choices of appropriate devices. A number of
technical literatures have been surveyed. Although
only few papers discuss about the effect of a pulse
shape on its power spectrum [3] but the effect of
pulse shapes is not correlated with the modulated
frequency spectrum. Here Section II explains the
theory regarding the digital phase modulation, pulse
shape, GNSS and BOC signals [5] and the
importance of pulse shape in GNSS spectrum.
Section III illustrates the simulation results with
varying pulse shape parameters. Section IV describes
the implementation of the theoretical observations in
the practical circuit with concluding the paper in
Section V.
II. THEORY
The digital phase modulated signal is represented
by
𝑠 𝑡 = cos(𝜔𝑐 𝑡 + 𝜑(𝑡)) (1)
ωc in equation (1) defines the carrier frequency
(𝜔𝑐 = 2π𝑓𝑐 ) and 𝜑(𝑡) shows the multi-level digital
baseband-encoded signal given by
𝜑 t = 𝑎 𝑘𝑟 𝑝𝑟 t − kT1≤r ≤n
−∞<𝑘<∞
(2)
𝑝𝑟 t is the pulse shape of duration T, i.e.
𝑝𝑟 t = 0; t < 0, 𝑡 > 𝑇 (3)
𝑓𝑜𝑟 𝑟 = 1,2,3, … … … , 𝑛
All the pulse shapes for n- multi-level signals are
assumed to be unique so equation (2) becomes
𝜑 t = 𝑎 𝑘𝑟 𝑝 t − kT1≤r ≤n
−∞<𝑘<∞
(4)
𝑎 𝑘𝑟 is discrete variable, which can take any value out
of n-levels at any time for duration T.
The variables 𝑎 𝑘𝑟 are mutually exclusive as only
one pulse signal can exist at a time.
The resultant multilevel digital phase-modulated
signal using equation (4) in equation (1) is
𝑠 𝑡 = cos[𝜔𝑐 𝑡 + 𝑎 𝑘𝑟 𝑝 t − kT1≤r ≤n
−∞<𝑘<∞
(5)
Equation (5) represents the fundamental digital
phase-modulated signal with uniform pulse shapes
with same timing characteristics, for simplifying the
spectral analysis. This equation shows that the
frequency spectrum of 𝑠 𝑡 depends greatly on the
pulse shape function 𝑝 t . This adds up many
RESEARCH ARTICLE OPEN ACCESS
2. Rahul Gupta et al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN : 2248-9622, Vol. 5, Issue 6, ( Part -1) June 2015, pp.65-69
www.ijera.com 66 | P a g e
discrete components in frequency spectrum at
frequencies shifted from 𝜔𝑐 by multiple of the timing
frequency (1/T) i.e. at 𝑓𝑐 ±
𝑘
𝑇
. Various factors of
𝑝 t like
(i) pulse duration (t ≤ T);
(ii) rise time (tr) and fall time (tf)
contribute to the unwanted components in frequency
spectrum which are discussed in section III.
The Global Navigation Satellite Systems (GNSS)
using space-based navigation technology are using
state-of-the-art Binary Offset Carrier (BOC)
modulation [5], [6] based on the spread spectrum [7].
This is an advanced modulation that better shares the
available frequency band among all the required
signals by increasing spectral separation. In this way,
the BOC modulation conserves the spectrum. This
sharing of frequency band with information at
different positions shifted from carrier frequency [8]
facilitates the interoperability and compatibility of
different navigation systems like GPS, Galileo,
IRNSS etc. Hence the unwanted components due to
pulse shape or otherwise are not allowed to be
transmitted from on-board satellite and are necessary
to avoid in modulated signal.
In this perspective, we carry theoretical analysis by
simulations of pulse shape effects on to BOC
modulation. It is observed that the duty cycle
variation of 10% results 30 dB rises in undesired
component and with the rise & fall time increase
from 1% to 5% of pulse duration T, the power of
undesired components increases by 7 dB.
III. SIMULATION
The multilevel digital modulated signal in
equation (5) is used, with the uniform pulse signals
having maximum duration (i.e. T) and zero rise-fall
times, to simulate the ideal situation. Assuming equal
probability of each level, the Fourier transform of
equation (5) relative to positive frequencies is given
by
𝑆𝑟 𝜔 =
𝑇
2
𝑒 𝑗 𝜑 𝑟 𝑒
𝑗 𝜔 𝑐−𝜔 𝑇
2
sin
𝜔 𝑐−𝜔 𝑇
2
𝜔 𝑐−𝜔 𝑇
2
2
(6)
where 𝜑𝑟 is the phase deviation of rth
level out of n-
pulses, those can be either positive or negative.
Therefore, the power spectrum of a multi-level
(equidistant and equi-probable) phase modulated
signal comes as
P 𝜔 =
𝑇
4
sin
𝜔 𝑐−𝜔 𝑇
2
𝜔 𝑐−𝜔 𝑇
2
2
(7)
In view of its importance in GNSS signals, the
BOC (5, 2) modulation technique is chosen for the
further analysis. This modulation technique of BOC
(5, 2) uses a subcarrier of 5.115 MHz for a spreaded
signal of data rate 2.046 Mbps [9]. Both are
multiplied to generate a BOC (5, 2) modulated
baseband multi-level digital signal at data rate of
10.23 Mbps (=1/T) as shown in Fig 1.
Fig.1. BOC (5, 2) Modulated Baseband Multi-Level
Digital Signal
As the equation (6) represents the pulse
frequency response, the power spectrum for BOC (5,
2) modulated signal at carrier frequency (𝜔𝑐) of
102.3 MHz is shown in Fig 2 based on equation (7).
This power spectrum clearly indicates that in case of
50% duty cycle and zero rise-fall time, there appears
no discrete or continuous component at frequency
𝜔𝑐 ±
1
𝑇
*
. Further analysis would consider only the
first component (k=1), assuming that other
components are out of the signal band and hence
filtered out before transmission.
The effects of pulse shape parameters on the
signal power spectrum are studied in the subsequent
subsections.
Fig.2. Power Spectrum at 𝜔𝑐 of 102.3 MHz for BOC
(5, 2) Modulated Signal with Pulse Duration T and
Zero Rise & Fall Times
*
Hereafter 𝜔𝑐 is taken as frequency (Hz), but in
standard it has unit of rad/sec.
A. DUTY CYCLE
Duty cycle of the used clock of 5.115 MHz is
another way to represent the pulse width (τ ≤ T)
of 𝑝 t , where the pulse period is T.
Fig.3. Pulse of Width 𝜏 ≤ T used to Represent Multi-
Level Digital Baseband Signal
X X
50 bps
Data
2.046 Mbps
Spreading Code
2.046 Mbps
Spreaded Data
5.115 MHz Clock
BOC(5,2)
Baseband Signal
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Here in BOC (5, 2) modulated signal the multi-
level digital baseband signals 𝜑 t are represented by
the pulses 𝑝 t of period T (=1/10.23 µsec) as shown
in Fig 3. When the clock has a duty cycle other than
50%, a continuous frequency pattern appears at
frequencies shifted from 𝜔𝑐 with multiples of
1
T
. Fig.
5 shows the power spectrum of BOC (5, 2)
modulated signal with clock of 48% duty cycle,
which states clearly that the undesired continuous
component has increased by 18 dB, compared to that
of Fig. 4 with 50% duty cycle.
Here considering zero rise and fall times, the plot
for integrated power of undesired continuous
component of 2.046 MHz band centered at 𝜔𝑐 ±
1
𝑇
with variation in duty cycle around 50% is shown in
Fig. 6.
Fig.4. Power Spectrum at 𝜔𝑐 of 102.3 MHz for
BOC(5, 2) Modulated Signal with Clock Duty Cycle
50% (𝜏 = T) and Zero Rise & Fall Times
Fig.5. Power Spectrum at 𝜔𝑐 of 102.3 MHz for BOC
(5, 2) Modulated Signal with Clock Duty Cycle 48%
(𝜏 < 𝑇) and Zero Rise & Fall Times
This quantifies that as duration of multi-level
digital modulated pulses varies from 50% to
50±10%, the continuous spectrum component at
frequency (𝜔𝑐 ±
1
𝑇
) increases by 30 dB. The
severity of this continuous spectral band can create
noise for other omnipresent GNSS signals.
Fig.6. Power of undesired band centered at 𝑓𝑐 ±
1𝑇, with 𝜔𝑐 of 102.3 MHz for BOC (5, 2), varying
with Clock Duty Cycle (𝜏 ≤ T) at Zero Rise & Fall
Times
B. RISE & FALL TIMES
Finite rise & fall times (tr & tf) in the baseband
multi-level digital modulated pulses, shown in Fig. 7,
contribute to the discrete frequency components at
frequencies (𝜔𝑐 ±
𝑘
𝑇
).
Fig.7. Pulse of width 𝑇 and finite rise & fall times
(𝑠 < 𝑇) used to represent multi-level digital
baseband signal
The localized power spectrum at 𝑓 𝑖. 𝑒. 𝜔𝑐 ±
𝑘
𝑇
decreases as (
1
𝜔4) as 𝜔 tends to infinite [3]. The
simulation results of BOC (5, 2) modulated signal
spectrum with pulses 𝑝 t of period T (=1/10.23
µsec) and finite tr & tf of 3 nsec, is shown in Fig. 8.
Fig.8. Power Spectrum at 𝜔𝑐 of 102.3 MHz for
BOC(5, 2) Modulated Signal with Clock Duty Cycle
50% (𝜏 = T) and 3 nsec Rise & Fall Times
40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
-30
-25
-20
-15
-10
-5
0
5
Power in BW of 2.046 MHz centered at (fc ± 1/T) v/s Duty Cycle
Duty Cycle (%)
Power(dBm)
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The appearance of discrete component at
𝜔𝑐 ±
1
𝑇
in spectrum of Fig.8 is visible, increased by
20 dB compared to that of Fig. 2, but the integrated
power in the undesired band around 𝜔𝑐 ±
1
𝑇
increases by 6 dB only. Hence a signal spectrum with
undesired discrete components is more vulnerable
than the undesired continuous (spreaded) component
to affect other GNSS signals.
Fig.9. Power of undesired discrete component at
𝜔𝑐 ±
1
𝑇
, with 𝜔𝑐 of 102.3 MHz for BOC (5, 2),
varying with Rise & Fall Times at 50% Clock Duty
Cycle (𝜏 ≤ T)
Considering the 50% duty cycle, the plot of
variation of the integrated power in the undesired
band around 𝜔𝑐 ±
1
𝑇
is shown in Fig. 9 which
indicates this power increase by 12 dB for tr & tf as
10% of T. Here it increases by around 7 dB when tr &
tf are increased from 0 to 4 nsec.
C. COMBINED EFFECT
The combined effect of pulse width and rise &
fall times is also studied here and the result, with duty
cycle of 45% and rise-fall time of 3 nsec, is shown in
Fig. 10. It indicates the increase in both the undesired
continuous and discrete components around 𝜔𝑐 ±
1
𝑇
.
Fig.10. Power Spectrum at 𝜔𝑐 of 102.3 MHz for
BOC (5, 2) Modulated Signal with Clock Duty Cycle
45% (𝜏 < 𝑇) and 3 nsec Rise & Fall Times
The power of undesired component v/s duty
cycle with different rise and fall times is shown in
Fig 11. It highlights the importance of rise-fall time
at duty cycle near to ideal i.e. 50%. But as the duty
cycle deviates more from the ideal condition, the
deviation in undesired power component due to rise-
fall time, becomes continuously negligible.
Fig.11. Power of undesired band centered at 𝜔𝑐 ±
1𝑇, with 𝜔𝑐 of 102.3 MHz for BOC (5, 2), v/s Clock
Duty Cycle (𝜏 ≤ T) at different Rise & Fall Times
IV. IMPLEMENTATION AND
RESULTS
A BOC (5, 2) modulator hardware as per Fig. 1
has been developed and tested with devices of
different timing parameters.
In hardware, the signal pulses are latched before
carrier signal multiplication which brings the pulse
width i.e. duty cycle of multilevel digital signals
towards ideal, therefore the effect of duty cycle
doesn‟t reflect in the implementation results. But the
rise and fall time parameters for each used device are
defined so the rise and fall time of multilevel digital
pulses is the only factor to degrade the spectrum in
real hardware.
Fig.12. Power Spectrum at 𝜔𝑐 of 102.3 MHz for
BOC (5, 2) Modulated Signal Designed with 74LS
TTL Devices
(a) The BOC (5, 2) modulator was designed using
the available slow speed 74 series TTL ICs of
„LS‟ class. The modulated power spectrum is
shown in Fig. 12 and it clearly indicates that due
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
-30
-28
-26
-24
-22
-20
-18
-16
-14
-12
Power in BW of 2.046 MHz centered at (fc ± 1/T) v/s Rise/Fall time
Rise/Fall time (nsec)
Power(dBm)
40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
-30
-25
-20
-15
-10
-5
0
5
Power in BW of 2.046 MHz centered at (fc ± 1/T) v/s Duty Cycle
Duty Cycle (%)
Power(dB)
rise-fall time= 0 nsec
rise-fall time= 5 nsec
rise-fall time= 10 nsec
rise-fall time= 15 nsec
rise-fall time= 20 nsec
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to high rise and fall times, discrete components
occur at frequency 𝜔𝑐 ±
1
𝑇
.
(b) Later, to remove these discrete frequency
components, a device of very low rise and fall
time was used in design.
Fig.13. Power Spectrum at 𝜔𝑐 of 102.3 MHz for
BOC (5, 2) Modulated Signal Designed using Fast
Speed 74F TTL Devices
The high speed 74 series TTL ICs of „F‟ class
were used which have the rise and fall times (~6
nsec) one fourth than „LS‟ class devices (~25 nsec).
The improved spectrum is shown in Fig. 13 having
tolerable discrete components at frequency 𝜔𝑐 ±
1𝑇which has decreased by almost 10 dB compared to
earlier configuration.
Hence, for a tolerable limit of 10 to 12 dB
increase in power of undesired component, the duty
cycle and rise-fall times can be deviated upto 1% and
5% respectively from the ideal condition. Above
analysis of shape and timing characteristics of the
multi-level digital modulated pulses shows that the
pulse duration and rise & fall times play a significant
role in the modulated spectrum which may be critical
in GNSS applications.
V. CONCLUSION
In this paper, the study of the pulse shape and
timing characteristics for a multi-level digital phase-
modulated signal has been accomplished. Here the
results, both of the simulated and developed
modulators clearly describe the importance of the
pulse shape in terms of duration and rise & fall times,
for a modulator and especially for Global Navigation
Satellite Systems (GNSS). So based on the above
analysis to study and find out the tolerable limits of
undesired power components, it‟s very important to
take the timing parameters, of devices to be used, in
consideration while designing a multi-level digital
phase modulator.
Acknowledgements
We like to express our gratitude to Director,
SAC, ISRO for his continuous support and
encouragement. We acknowledge the support
received from Shri D K Das, DD/SNPA. We are also
grateful to the Indian Space Research Organization‟s
Navigation project, for providing the funds and other
logistics for this research and development.
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