Kanok Janchitrapongvej

Modification of data transmission filter with Generalized Bessel transformation

This paper present modification of data transmission filter by the application of Generalized Bessel transformations with rational filter. The technique gives the denominator of filter transfer function in analytic closed form, while its numerator is determined by solving a set of transmission zeros and even polynomial of order. The results to filter is straightforward and will be given in a later more detailed contribution together with comparison with the other existing design methods, such a comparison reveals the superiority of the present technique.

A robust variable step-size LMS-like algorithm for a second-order adaptive IIR notch filter for frequency detection

The best adaptive algorithm requires fast convergence speed, low variance, unbias and low steady-state mean square error (MSE) in both low and high signal-to-noise ratio (SNR) situations. We have proposed a robust variable step-size LMS-like algorithm (VS-LMS-L) for a second-order adaptive IIR notch filter for frequency detection in radar, sonar and communication systems. This algorithm is compared with the conventional LMS-like algorithm called the plain gradient algorithm (PG). The time-varying step-size /spl mu/(n) is adjusted by using the square of the time-averaged estimate of autocorrelation of the present output signal y(n) and the past one y(n-1). This technique can reject the effect of the uncorrelated noise sequence on the step-size update, resulting in a small MSE due to the small final /spl mu/(n). Moreover, this algorithm can also improve the convergence speed by comparison with the PG at the same MSE value.

On Design of Video Equalizer for Distorted Chrominance based on the Bernstein Polynomials

In this paper, we propose a design of video equalizer for compensating the amplitude of chrominance signal based on the Bernstein Polynomials. The use of Bernstein Polynomials in analog filter obtain the advantages are linear phase filter, several parameters that control the amount of phase and magnitude, and flexible for variable of phase. In addition, experimental results are carried out by using the modulated 20T sine squared signal. It is shown that the proposed video equalizer can be enhanced or compressed the amplitude chrominance distortion in color television transmission

Continuous-time low-pass filter using an active distributed mosfet transistor

This paper describes continuous-time low-pass filter using an enhancement MOSFET transistor as a double uniformly distributed RC line (DUE). The proposed circuit configuration consists of a new low-pass active distributed MOSFET filter and one pole gain amplifier. For continuous-time low-pass filter using proposed frequency adjustable type circuit, the experimental result of the frequency characteristics give us a good agreement with theoretical values. The proposed circuit can all used in modem electronic communication systems and most measuring equipments.

Notch frequency adjustable active filter using uniformly distributed RC line

The paper describes a new notch frequency adjustable type filter using a uniformly distributed RC line (URC) with three capacitive layers. The proposed circuit consists of one URC with three capacitive (C/sub 0/, C/sub 1/ and C/sub 2/) layers and a single gain amplifier. /spl alpha//sub 1/, /spl alpha//sub 2/ of the circuits are used to adjust the notch tunable frequency and K is used to control the minimum stop band loss. The structure reduces the amount of circuit complexity and is simple to use for filter applications. Finally, computer simulation results showed good agreement with theoretical values. Sensitivity analysis is also carried out.

An IIR digital video equalizer design with the Bernstein Polynomial and generalized bilinear transformation for gain chrominance distortion

Video equalizer design for compensated the distortion of the chrominance amplitude in color television transmission system is presented. The approximation is based on the Bernstein polynomials and generalized bilinear transformation to obtain the transfer function. This approach has several parameters can be varied satisfying stability conditions. And the advantages of the Bernstein polynomials when compared to the Butterworth, Chebyshev and Thomson polynomials are three parameters available control the amount of phase and magnitude, linear phase, and flexible for variable of phase. Among all referred advantages so that these methodologies were applied in this paper. In addition, the pulse and bar test signal which has been used to measure linear waveform distortion in TV system is special the modulated 20T sine squared pulse with color sub-carrier 4.43 MHz for PAL system. As a result, the proposed digital video equalizer can be enhance and compress the gain chrominance distortion without degraded it phase characteristic.

Variable step-size modified MNG algorithm for adaptive IIR notch filter for detection of sinusoids

In this paper proposes an addition of a variable step-size modified memoryless nonlinear gradient (MNG) algorithm for a second-order adaptive IIR notch filter for detection of sinusoids in noise environment. The structure of the adaptive IIR notch filter is based on direct form structure and lattice form structure. The objective of variable step-size (VSS) algorithm is to optimize the filter coefficient. The computer simulation results are shown that the proposed algorithm provides fast convergence speed, low mean square error, low variance of filter coefficients and high impulsive noise robustness.

A new algorithm of adaptive IIR notch filter for the detection of sinusoids

This paper aims to improved the convergence speed, steady-state mean square error and variance of the filter coefficient. The proposed adaptive algorithm is for a second-order adaptive IIR notch filter based on gradient algorithm. The simulation results shown that the proposed algorithm provides fast convergence speed, and has low steady-state mean square error and low variance of filter coefficient.

Capacitive double layers uniformly distributed RC line and its applications to active filters

A technique for active low pass filter designed by using double layers capacitive uniformly distributed RC line (DURC) is presented. The proposed circuit configuration consists of two DURC and a single gain amplifier. Herein, /spl alpha/ and K parameters of the circuit are used to improve the magnitude response. The structure reduces an amount of circuit complexity and simple to use for filter applications. The simulation by P-SPICE of the amplitude response and sensitivities are also given.

Active notch uniformly distributed RC circuit and their application

Many application of the RC parallel-T network, only two performance characteristics are considered important the frequency and depth of the attenuation notch. In this paper the design presented, active notch distributed RC network (URmacrCmacr) circuit from design values. The proposed circuit configuration consists of URmacrCmacr, one external resistor (Rn) or capacitor (Cn) and single gain amplifier. The parameters of the proposed circuit can be adjusted to improve the magnitude response with notch tunable frequency. This structure reduces an amount of circuit complexity and is simple to use for application. The experiments and computer simulation showed good agreement with theoretical values. The active notch URmacrCmacr can application to experiments high frequency active band-pass filter, sinusoidal wave oscillator and frequency discriminator.