Koseeyaporn, Jeerasuda
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Preferred name
Koseeyaporn, Jeerasuda
Alternative Name
Koseeyaporn, J.
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Email
jeerasuda.ko@kmitl.ac.th
74 results
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Item type:Publication, A new automated heart defect detection based on signals and systems concept(2006-12-01); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Amplitude demodulation based on time-varying forced input of second-order oscillator circuit(2009-12-01); In this article, a novel coherent amplitude demodulation based on time-varying force function of secondorder oscillator circuit and injection locking Phenomenon is proposed. The compactness of demodulation circuit is obtained because amplitude demodulation mechanism is inherent in one oscillator circuit. With injection locking property, frequency and phase of the oscillator is identical to that of the transmitted carrier. Based on time varying force function which is an AM signal, coherent demodulation is taken place. In laboratory experiment, the Colpitts oscillator at UHF band is employed where experimental results agree well with the proposed principle. ©2009 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Novel Double Slope Frequency Shift Chirp Symbol(2024-01-01); One of the most significant concerns in serial digital communication is the synchronization of data bits between the transmitter and receiver. Therefore, the preferred coding symbols should contain an inherited clock signal. The cyclic-shift chirp, which is primarily used in long-range systems, employs a single slope in a symbol, which contains few information for synchronization. Hence, two new forms of cyclic-shift chirp symbols are proposed herein. The associated coding schemes are based on the use of a dual slope within one symbol. Synchronization is inherited in the coding symbol using a dual slope. Additionally, both proposed coding schemes utilize the same decoding technique. The decoded chirp symbol is in the form of a pulse width modulation signal, which can be used for synchronization and retrieving data bits from their duty cycle. The simulation results show that the coding and decoding processes of the proposed coding schemes align with those of a theoretical framework. The error performance analysis for the proposed detection scheme is given and the results of error probability analysis are consistent with the simulation results. Moreover, under a Rayleigh fading channel, the proposed coding schemes provide superior performance compared with other comparable coding schemes. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Inverse tangent based adaptive IIR notch filter(2006-12-01); The inverse tangent based second-order adaptive IIR notch filter (ITANF) is presented in this paper. It is well known that the gradient-based adaptive IIR notch filter (ANF) has inherent low convergence speed due to the flattened error function. Moreover, the magnitude of error function depends on magnitude of sinusoid which implies that the speed of convergence of the gradient-based adaptive algorithm also depends on the magnitude of an input signal. To improve such drawback, the new inverse tangent based adaptive algorithm for a second order IIR notch filter is therefore proposed. The proposed algorithm employs the ratio of output to input signals as an error criterion where the inverse tangent value of the ratio is employed to adapt the filter parameter. It is found that the proposed algorithm provides not only high speed convergence but also high impulse noise robustness. The simulation results confirm that the performance of the proposed algorithm has been improved over the conventional ANF. ©2006 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Pulse width modulation based on phase locked loop(2008-10-06); A new circuit structure which improves performance of a pulse width modulator is proposed in this paper. The proposed PWM circuit is based on a phase locked loop (PLL) system where the input signal is fed to combine with the output of a phase detector (PD). which it achieve a high accuracy PWM output. In addition, we also use R-S flip-flop and monostable circuit as a phase detector which give rise to get a PWM modulator that wide input range. The experimental result agree well with an analytical result. © 2008 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Indirect frequency estimation based on second-order adaptive FIR notch filter(2009-07-01); This paper deals with estimating the frequency of sinusoidal signal buried in broad band noise. The simple unbiased indirect frequency estimation (IFE) algorithm is proposed for a second-order adaptive finite impulse response (FIR) notch filter with constrained zeros. The technique of estimating input noise variance is employed to remove the bias existing in the estimated filter parameter. Also, the difference equation for the convergence of the expectation of the estimated parameter and the closed-form of steady state estimation mean square error (MSE) are derived. In addition, extensive simulations are conducted to corroborate the efficiency of the proposed estimator with the theoretical analysis. © 2009 Elsevier B.V. All rights reserved. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Frequency Estimation of Short Range Radar Using Adaptive FIR Notch Filter and SAGC for Velocity Detection(2018-09-11); This research proposes the velocity detection for short range radar using an adaptive FIR notch filter and a sinusoidal automatic gain control scheme (SAGC). A HB 100 module with amplifying gain of 20 times produces Doppler signal and this signal is fed to a laptop through a sound card with sampling frequency of 8000 Hertz. The signal is processed by the SAGC to amplify the amplitude of the signal to be unity. To detect the frequency of the signal, an algorithm of indirect frequency estimation based on adaptive FIR notch filter is performed. After that, the resulting frequency is converted to velocity. All procedures in this work are processed by MATLAB program. The results of the proposed method have better signal to noise ratio compared with existing method. In addition, the presented work consumes low computational time. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Performance analysis of soft switch network based on Jackson network theory(2008-12-01); In this paper, mathematical analyses for three architectures of soft switch network adopted from Xu peng et al. are presented. The proposed models are based on the Jackson network theory. They are derived to provide closed form solution for predicting the capacity of the soft switch network. In addition, simulation results obtained from the proposed mathematical models are compared with numerical results of Xu Peng et al. It is found that they are well correspondent each other. The proposed mathematical analyses thus more efficient methods to predict capacity of soft switch network. (ICCCAS'08). ©2008 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A new technique for routing and wavelength assignment for WDM mesh networks(2008-12-01); This article proposes a new technique for routing and wavelength assignment in WDM circuit switch mesh networks, supporting both wavelength conversion and without wavelength conversion systems. With this technique, the network can be preceded by accomplishing two processes : one is searching for the shortest main route and the second-shortest alternative route and another is randomly choosing wavelength. Moreover, an analytical model by using Erlang's B formula to predict the probability blocking is also proposed. The comparative results between the analytical model with numerical model are demonstrated. The results revealed that the proposed technique is superior to the method with using only the single shortest path. In addition, the results obtained from the analytical model are agreed well with the numerical results obtained from simulations. © 2008 IEEE. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Kalman filtering adaptive stabilization of robot manipulator under sea wave interference(2005-01-01); Koseeyaporn, PoolsakThis paper proposes an adaptive position stabilization of a robot manipulator situated on the top of a floating object. An adaptive controller based on model-based approach is designed to stabilize the robot target position, which is interfered by random sea wave. The rolling motion of the floating object caused by sea wave is modeled as nonlinear second-order differential equation. For online control achievement, the estimation of the rolling angle based on Kalman filtering is applied. In addition, inverse kinematics solution of a 6-axis articulated robot is utilized to provide the desired joint angles for the controller. The several viewpoints including control error, parameter convergence, and tip position error retrieved from 3D graphical simulator are provided to demonstrate the performance of the controlled system. © 2005 IEEE.