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Linear prediction based adaptive algorithm for a complex sinusoidal frequency estimation
(2013-06-01)
Punchalard, R.
;
Wardkein, P.
The complex direct frequency estimation (CDFE) adaptive algorithm is developed and proposed in this paper. The motivation of this work is obtained from the previous real DFE (RDFE) adaptive algorithm. The methodology of the CDFE is based on the linear prediction property of complex sinusoidal signals. The proposed algorithm is unbiased and computationally efficient. Moreover, it is easy to implement and appropriate for real-time applications. In addition, the convergence behavior is analyzed and the steady-state mean square error (MSE) of the frequency estimate is derived in closed form. Computer simulations are treated to corroborate the theoretical analysis. © 2013 Published by Elsevier GmbH.
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Echo cancellation using the new variable step-size algorithm adaptive lattice filters
(2006-12-01)
Sukhumalwong, S.
;
Benjangkaprasert, C.
;
Anantrasirichai, N.
;
Janchitrapongvej, K.
Adaptive algorithms are widely used for various application. One challenging application is an echo canceller in the long distance telephony network. Echo return loss and impulse response are important characteristics of an echo path for the design of echo cancellers. The performance of the echo cancellers depends on the choice of the adaptive filtering algorithm. This paper proposes the new variable step-size algorithm for adaptive lattice form structure filter for echo canceller. The proposed algorithm is an excellent in convergence speed, and provides high performance. The structure's stability had improved by Echo Return Loss Enhancement (ERLE). © 2006 ICASE.
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Performance of a robust variable step-size LMS adaptive algorithm for multiple echo cancellation in telephone network
(2006-12-01)
Tingchan, W.
;
Chutchavong, V.
;
Benjangkaprasert, C.
The used of adaptive echo canceller is to estimate the impulse response of echo path and synthesizes an echo replica to subtracted from the echo signal in telephone network. Moreover, most echo paths change their characteristics frequency according to the noisy environment. To cancel multiple echoes, the number of tap coefficients of a conventional echo canceller must be large. The length of the echo canceller will directly affect both the degree of accuracy and the convergence speed the adaptation process. In this paper presents the comparison of the performance of the robust variable step-size LMS adaptive algorithm and the LMS adaptive algorithm for cancels multiple echoes signal in telephone networks. The core of this paper is a multiple delay estimator, which estimates and distributes delays to each individual fixed length short echo canceller. The simulation results are show that with the delays given, the robust variable step-size LMS adaptive algorithm can update the echo path accurately. © 2006 ICASE.
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Adaptive echo cancellation using variable step-size algorithm lattice filters
(2006-01-01)
Sukhumalwong, S.
;
Benjangkaprasert, C.
Adaptive algorithms are widely used for various applications. One challenging application is an echo canceller in the long distance telephony network. Echo return loss and impulse response are important characteristics of an echo path for the design of echo cancellers. The performance of the echo cancellers depends on the choice of the adaptive filtering algorithm. This paper proposes the new variable step-size algorithm for adaptive lattice form structure filter for echo canceller in telephone network. The proposed algorithm is an excellent in convergence speed, and provides high performance. The structure's stability had improved by Echo Return Loss Enhancement (ERLE). © 2006 IEEE.
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A new algorithm of adaptive IIR notch filter for the detection of sinusoids
(2002-01-01)
Tupchai, P.
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Benjangkaprasert, C.
;
Sangaroon, O.
;
Janchitrapongvej, K.
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.
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A new gradient-based algorithm using variable step-size technique and its application [adaptive IIR notch filter]
(2002-01-01)
Benjangkaprasert, C.
;
Jorphochaudom, S.
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Phuvasitkul, S.
;
Anantrasirichai, N.
In this paper, a new class of gradient-based algorithm by using variable step-size technique for a second-order adaptive IIR notch filter is presented. An adaptation step-size parameter for the algorithm is worked out from the output signal and the gradient signal. The adaptive algorithm is used for detection of a sinusoid with additive white Gaussian noise, impulse noise and cancellation of 50-Hz interference in the recording of electrocardiogram signals. The performance of this algorithm is proved here to give high convergence speed, high impulse noise robustness and good efficiency of 50-Hz interference cancellation. Finally, the results of computer simulation are given to demonstrate the performance of the proposed algorithm for the adaptive IIR notch filter.
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On the algorithm for adaptive noise canceller with parallel block structure
(2002-01-01)
Kidakorn, P.
;
Rattanakoch, W.
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Kimpan, C.
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Pin-Ngern, Ouen
;
Noppanakeepong, S.
An adaptive algorithm for detecting a single sinusoid of unknown frequency corrupted by Gaussian noise was proposed by Nishimura et al. (Trans. IEICE, vol. J72-A, no. 5, pp.786-794, 1989) using a IIR band pass filter with a variable center frequency and parallel block structure for fast processing. In 1996 an adaptive algorithm was investigated which solved the problem whereby the presence of several input frequencies led to the situation of it being impossible to achieve convergence using the new algorithm proposed by Takahashi et al. (Proc. IEEE APCCAS'94, pp. 376-381, 1994). However, the control signal generated by the new algorithm, used for adjusting the center frequency of the band pass filter, still jitters in spite of its convergence. In this paper, in addition to using the output in an adaptive algorithm as proposed, the input signal is used as an auxiliary or reference signal. In this way the jitter on the control signal can be reduced significantly, with the same convergence rate, with little added computational complexity.
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A robust variable step-size LMS-like algorithm for a second-order adaptive IIR notch filter for frequency detection
(2001-01-01)
Punchalard, R.
;
Benjangkaprasert, C.
;
Anantrasirichai, N.
;
Janchitrapongvej, K.
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 μ(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 μ(n). Moreover, this algorithm can also improve the convergence speed by comparison with the PG at the same MSE value.

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