• 전기학회논문지P
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• 제62권3호
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• pp.111-116
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• 2013

Noise problem that occurs on the road is raising a lot of problems in the economic, social and environmental aspects. The objective of this paper is to propose ANC(active noise cancellation)-based road traffic noise reduction algorithm-model which can reduce noise by generating frequency opposed to noise sources to improve and complement the problem that existing physical form of a noise barrier. In this paper, we measured the noise characteristic from collection of two difference car noise also ANC simulation has been performed by using road traffic noises input. In order to compare the control performance, we performed noise reduction simulation of ANC by filtered-X LMS algorithm and delayed control signal injection. As a result of this simulation, we confirmed that convergence performance and noise decrease effect to the filtered-X LMS algorithm by inputting the road traffic noise.

• 한국통신학회논문지
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• 제19권8호
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• pp.1528-1535
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• 1994

본 논문에서는 적응 능동소음제어를 위한 새로운 오차경로 인식 방법을 통한 filtered-X LMS(least mean square) 알고리듬을 제안하였다. 제안한 알고리듬에서는 3개의 마이크로폰과 이중루프제어를 이용하여 오차경로의 전달 특성을 온라인으로 정확히 인식하도록 하였다. 덕트를 통한 소음이 정형파인 경우와 실제 공조기의 소음에 대하여 컴퓨터 시뮬레이션을 각각 수행한 결과, 제안한 방식은 입력소음에 비하여 각각 평균 29.1dB 및 10.4dB 정도의 소음레벨이 감쇠됨을 확인하였다. 이는 Eriksson의 방법보다 각각 평균 0.5dB 및 2.5dB 정도 개선된 것이다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.357-363
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• 2009

This paper deals with the Filtered-x Least Mean Square algorithm for a active vibration control in vehicle vibration reduction. Before applying the proposed FxLMS algorithm to automobile, the performance of the FxLMS algorithm is simulated using sensor data of a vehicle. The FxLMS algorithm requires that reference signal be a representation of disturbance signal and the plant model be incorporated into the computation path. To this end, The system identification is carried out to obtain the plant model based on the measurement results. A tachometer signal is used as reference signal. The FxLMS control algorithm is first tested using simulation and applied to a vehicle. Experimental results show that the proposed control algorithm can reduce vibration level in a short period of time.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.305-344
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• 2008

This paper presents the active control of flexible beam vibration. The beam was excited by a steady-state point force by mini shaker and the control was performed by mini shaker. To perform active control, least-mean-square (LMS) algorithm was used because it can easily obtain the complex transfer function in real-time. So an adaptive controller based on Filtered-X LMS algorithm was used and the controller was defined by minimizing the square of the response at a location of error sensor. In order to fine out performance tendency, input amplitude was changed in several cases and active vibration control was performed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.184.1-184.1
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• 2005

• 한국소음진동공학회논문집
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• 제27권1호
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• pp.87-93
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• 2017

This paper investigates active noise control of tower-type air conditioners using the filtered-x least mean square (FXLMS) algorithm to reduce fan blower noise transmission. Firstly, the main components required for the active control system including the error sensor, the control speaker and the reference sensors are selected. Since the noise could significantly reduce if the reference signal includes every frequency response information, a various reference signals from accelerometers and a microphone are used. Secondly, the controller based on the FXLMS algorithm with a single-channel reference signal is implemented. Then, the control performance is examined experimentally for the different reference signals. It is found that the accelerometer signal well possesses the motor vibration related noise and a microphone signal could includes global noise. When using the reference signal with a microphone located near the motor and the fan blower, the active control system reduces the noise globally, except for several peaks.

• 동력기계공학회지
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• 제14권5호
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• pp.56-62
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• 2010

In this paper, a recurrent cerebellar modulation articulation control (RCMAC) has been developed for improvement of noise attenuation performance in active noise control system. For the narrow band noise, a filter-x least mean square (FXLMS) method has bee frequently employed as an algorithm for active noise control (ANC) and has a partial satisfactory noise attenuation performance. However, noise attenuation performance of an ANC system with FXLMS method is poor for broad band noise and nonlinear path since it has linear filtering structure. Thus, an ANC system using RCMAC is proposed to improve this problem. Some simulations in duct system using harmonic motor noise and KTX cabin noise as a noise source were executed. It is shown that satisfactory noise attenuation performance can be obtained.

• 한국음향학회지
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• 제14권2호
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• pp.40-49
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• 1995

Filtered-x 최소 평균 제곱(LMS:Least Mean Square) 적응 필터가 능동 소음 제거에 사용될 때 적응 필터 출력과 오차신호 사이의 전달 특성 추정이 요구된다. 본 논문은 소음이 복구 정현파(multiple sinusoids) 신호로 구성될 때 filtered-x 적응 소음 제거 알고리듬을 유도하고 수렴 특성을 이론적으로 분석하였다. 알고리듬의 수렴 분석 결과, 알고리듬에 사용되 파라미터 추정의 부정확성으로 수렴 성능 저하를 가져오는데 위상 추정 오차와 추정 이득에 의하여 특정 지워진다는 사실을 알았다. 특히, filtered-x 최소 평균 제곱 알고리듬의 수렴은 위상 응답 추정의 정확도로부터 많은 영향을 받는다는 것을 보였다. 이 알고리듬에 대한 컴퓨터 모의 실험 결과 이론적인 수렴 분석과 잘 일치함을 보였다.

• 전기학회논문지P
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• 제63권3호
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• pp.157-162
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• 2014

The active noise control(ANC) method for noise problems solution generally uses filtered-X LMS algorithms. However, Filtered-X LMS algorithms were mainly used but these had a limitation that had to measure a transfer function of secondary noise path. However, newly proposed correlation-LMS algorithms have slightly much calculation and are minutely behind performance, these have a advantage not in measuring transfer function onerously so that we can easily adapt these in real time. Thus Co-LMS algorithm was developed to improve the real-time implementation performance under the variable input noise such as road noise environment. In this paper, the performance of the Co-LMS is presented in comparison with that of the Filtered-X LMS algorithm. Simulation results show that active noise control using Co-LMS have slightly much calculation and are minutely behind performance, these have a advantage not in measuring transfer function onerously so that we can easily adapt these in real time.

• 한국음향학회지
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• 제34권2호
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• pp.130-137
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• 2015

본 논문에서는 충격성 소음의 능동 제어를 위해 제안된 Modified Filtered-x Affine Projection Sign Algorithm(MFxAPSA)의 수렴 속도를 향상시키기 위한 새로운 MFxAPSA를 제안하였다. 능동 소음 제어에서 소음원이 충격성 잡음을 포함하는 경우, 무한한 크기의 분산을 갖으려는 성질 때문에 Filtered-x affine Projection Sign Algorithm(FxLMS)와 같이 2차 모멘트를 기반으로 유도된 적응 알고리즘들은 수렴 속도가 매우 느리거나 발산하는 경향이 있다. MFxAPSA는 기존에 제안된 Affine Projection Sign Algorithm(APSA)을 능동 충격성 소음 제어에 적용한 알고리즘이다. APSA은 역행렬 연산을 요구하지 않는다는 장점으로 인해 낮은 연산량을 요구하는 능동 소음 제어에 적합하다. 본 논문에서는 기존의 MFxAPSA와 같이 역행렬 연산을 요구하지 않으면서 더 좋은 수렴 특성을 가지는 새로운 MFxAPSA를 제안하였다. 두 알고리즘의 성능을 비교하는 컴퓨터 모의 실험을 수행하여 제안된 알고리즘의 수렴 특성이 더 좋음을 보였다.