• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.247-249
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• 2009

This paper investigates active noise control(ANC) of a rectangular cavity using single channel filtered-x least mean square(FXLMS) algorithms to reduce interior noise globally. To obtain global reduction of the interior noise, multichannel active control should be incorporated in general. We, however, examined firstly the optimal location of the secondary speaker that produces a global reduction of the interior noise field. We then investigated the frequency characteristics of the reduction to yield the effective frequency band of the active control system. It follows that the secondary speaker should be located as close to the primary source as possible in order to obtain global reduction.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권12호
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• pp.827-833
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• 2004

In active noise control (ANC) systems, the error-reduction performance of the conventional Filtered-X Least Mean Square (FXLMS) algorithm may be affected by nonlinear distortions in the secondary path such as in the power amplifiers, loudspeakers and transducers. In this paper, a nonlinear FXLMS algorithm with high error-reduction performance is proposed to compensate for undesirable nonlinearities in the secondary-path of ANC systems by employing the inverse Volterra filtering approach. In particular, the proposed approach is based on the utilization of the conventional P-th order inverse approach to nonlinearity compensation in the secondary path of ANC systems. Finally, the simulation results showed that the proposed approach yields a better nonlinearity compensation performance for the ANC systems with a nonlinear secondary path than the conventional FXLMS.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.251-252
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• 2007

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.688-689
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• 2009

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.503-504
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• 2008

• 대한기계학회논문집A
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• 제30권8호
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• pp.897-905
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• 2006

This study considers an experimental design of disturbance compensation control to improve stabilization performance of main battle tanks. An adaptive non-parametric design technique based on the Filtered-x Least Mean Square(FXLMS) algorithm is applied in the consideration of model uncertainties. The optimal compensator is designed by two-step design procedures: determination of frequency response function of the disturbance compensator which can cancel the disturbance of series of single harmonics by using the FXLMS algorithm and determination of the compensator polynomial which can fit the frequency response function obtained in the first step optimally by using a curve fitting technique. The disturbance compensator is applied to a simple experimental gun-torsion bar-motor system which simulates gun driving servo-system. Along with experimental results, the feasibility of the proposed technique is illustrated. Experimental results demonstrate that the proposed control reduces the standard deviation of stabilization error to 47.6% that by feedback control alone. The directional properties of the FXLMS Algorithm such as the direction of convergence and its convergence speed are also verified experimentally.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.644-646
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• 1998

The main drawback of filtered-X LMS(FXLMS) algorithm for the ANC of broadband noises is its low convergence speed when the filtered reference signals are strongly correlated, producing a large eigenvalue spread in correlation matrix. This correlation can be caused either by autocorrelation of the signals of the reference sensors, or by coupling between the error path which introduces intercorrelation in the filtered reference signals. In this paper, we introduce a transform domain FXLMS(TD-FXLMS) algorithm that has a high convergence speed by orthogonal transform's decorrelation properties.

• 전기학회논문지P
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• 제63권4호
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• pp.260-265
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• 2014

Recently, many active noise control (ANC) systems, which employ the adaptive filter controlling method, have been reported for eliminating unwanted noise. ANC systems based on the filtered-X least mean square (FXLMS) algorithm have a problem with compensating the acoustic feedback of secondary route. It is difficult to apply the real time, because transfer function of secondary route must be measured by off-line method to solve this problem. In this paper, we propose the ANC system that applies a correlation LMS(CLMS) algorithm for improving a problem of transfer function measurement. The proposed algorithm is based on input of road noise. The proposed ANC systems have an advantage of real-time process without degradation of performance, although there are many calculation compared with FXLMS algorithm.

• 제어로봇시스템학회논문지
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• 제13권6호
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• pp.547-554
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• 2007

This thesis presents a kind of active noise control(ANC) algorithm for reducing noise due to engine inside a car. The proposed control algorithm is, by using WP(Wavelet Packet), a one improving the instability due to delay of noise transmission and the lack of response ability for the rapid change of noise, which are defects of the existing FXLMS(Filtered-X Least Mean Square) algorithm. The chief character of this system is a thing that faster operation than the FXLMS is implemented by inserting WP in the secondary path. In other words, WP implements parallel operation. Then, the weights of filter in the adaptive algorithm will be updated faster. In addition, because WP have so excellent a resolution, they can process very minute noise. The efficiency of this control algorithm will be demonstrated in the matlab simulation and in the actual experiments by using a Labview program and a car.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2479-2482
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• 2003

능동소음제어 시스템에서 많이 사용되어 온 적응 알고리듬은 filtered-X LMS (FXLMS) 알고리듬으로, 이 알고리듬에서의 수렴속도는 필터링 된 신호에 의해서 좌우되기 때문에 FXLMS 적용시 실제 수렴성능이 저하되거나 수렴이 안 되는 경우도 발생할 수 있다. 본 논문의 목적은 변환영역에서 능동소음제어 시스템의 2차 경로 모델링을 행함으로써 전체 능동소음제어 시스템 동작의 수렴성능을 향상시키려는 것이다