Effect of a tilting reflective plane on the performance of an active noise control system

2021 ◽  
pp. 107754632110317
Author(s):  
Sajaad Boodoo ◽  
Mohammad R Paurobally ◽  
Yasdeo Bissessur
Keyword(s):  
Control System ◽  
Noise Reduction ◽  
Noise Control ◽  
Single Channel ◽  
Active Noise Control ◽  
Real Life ◽  
Orientation Angle ◽  
Secondary Source ◽  
Living Room ◽  
Active Noise

This article presents the results of an investigation of the noise reduction performance of a single-channel active noise control system in the presence of a tilting reflective plane. It is shown that the noise reduction achieved by the system depends upon the orientation angle of the panel and on the separation distances between both the primary and the secondary source and the reflective panel. It is also observed that the maximum noise reduction is obtained when the reflective panel is vertical and when the separation distance is less than about 0.13 of the wavelength at the frequency of interest. When the panel is moved away, the maximum noise reduction occurs at other tilting angles. Experiments were carried out in a real living room which is close to real-life situations. It is found that there is an improvement in the extent of the quiet zone in the presence of the panel. The reduction in sound pressure level is also better with the reflective panel, which is up to 20 dB.

Secondary Source Modeling Based on Analogue Circuits of Electrical Mechanical and Acoustical Systems

2011 ◽  
Vol 328-330 ◽  
pp. 2265-2269
Author(s):  
Yong Hong Nie ◽  
Jun Sheng Cheng
Keyword(s):  
Control System ◽  
Transfer Function ◽  
Noise Reduction ◽  
Noise Control ◽  
Active Noise Control ◽  
Secondary Source ◽  
Source Modeling ◽  
Ideal Model ◽  
Active Noise ◽  
Analogue Circuits

A method of secondary source modeling based on analogue circuits of electrical, mechanical and acoustical systems (SSM-ACEMAS) was provided in order to reduce the mismatch of transfer function estimation of secondary path in the simulation of active noise control (ANC) system. The convergence range and noise reduction performance of the system with SSM-ACEMAS and Filtered-X LMS algorithm were investigated. The results show that the transfer function of such a secondary source model has different amplitude and phase from the ideal model, which makes the noise reduction performance of an ANC system be much worse than the one with ideal model. Meantime, the convergence range of the control system is increased at low frequencies while decreased at high frequencies. The proposed model can provide a new method of secondary source modeling for further research on the simulation of active noise control system.

Psychoacoustic active noise control system based on empirical mode decomposition

2019 ◽  
Vol 67 (5) ◽  
pp. 332-349
Author(s):  
Yonghong Nie ◽  
Yu Liu ◽  
Guofeng Li ◽  
Ganqing Zhang
Keyword(s):  
Control System ◽  
Noise Reduction ◽  
Empirical Mode Decomposition ◽  
Noise Control ◽  
Active Noise Control ◽  
Peak Frequency ◽  
Least Mean Square ◽  
Shaping Filter ◽  
Active Noise ◽  
Mode Decomposition

A psychoacoustic active noise control (ANC) system based on empirical mode decomposition (EMD) is proposed and implemented to improve the noise reduction performance of the control system. The noise source signal is decomposed by EMD, and the psychoacoustic parameter â–œloudnessâ–? of each intrinsic mode function (IMF) is initially calculated in such a system. Thereafter, the high-pass psychoacoustic weighting filter used to shape the error and reference signals is designed adaptively and automatically according to the loudness, peak frequency, and amplitude of each IMF. Three different ANC systems are simulated, and the sound pressure levels and loudness of their residual error signals are compared. The results demonstrate that the filter designed using this method can restrain the components of noise sources with small loudness better than the A-weighting shaping filter, so that the proposed control system can improve the noise reduction compared to those of the filtered-x least mean square and A-weighting shaping filters. Finally, the computational complexity of the three ANC systems is analyzed and compared.

scholarly journals Convex combination-based active impulse noise control system

2019 ◽  
Vol 39 (1) ◽  
pp. 190-202 ◽  
Author(s):  
Ning Yu ◽  
Zhaoxia Li ◽  
Yinfeng Wu ◽  
Renjian Feng ◽  
Bin Chen
Keyword(s):  
Control System ◽  
Noise Reduction ◽  
Impulse Noise ◽  
Noise Control ◽  
Convex Combination ◽  
Active Noise Control ◽  
Lms Algorithm ◽  
Frequency Noise ◽  
Active Noise ◽  
Risk Sensitive

Active noise control shows a good performance on the suppression of the low-frequency noise and hence it is widely applied. However, the traditional active noise control systems are unsatisfactory in controlling impulse noise in practical situations. A method based on the convex combination of filtered-x least mean square and filtered-x minimum kernel risk-sensitive loss adaptive algorithms (CFxLM) is presented to efficiently suppress impulse noise. Due to the simplicity of the LMS algorithm, the related filter is selected as the fast filter. Because the minimum kernel risk-sensitive loss algorithm is robust to impulse noise and can offer good convergence performance, we first apply it to the active noise control system and select the corresponding filter as the slow one. The proposed CFxLM algorithm can achieve both fast convergence and good noise reduction and any prior knowledge of reference noise is unnecessary. Extensive simulations demonstrate the superior noise reduction capability of the developed CFxLM-based active noise control system in controlling impulse noise.

scholarly journals Dual-Zone Active Noise Control Algorithm

2019 ◽  
Vol 10 (1) ◽  
pp. 4
Author(s):  
Ran Wang ◽  
Xiaolin Wang ◽  
Jingwei Liu ◽  
Jun Yang
Keyword(s):  
Noise Reduction ◽  
Least Squares ◽  
Control Algorithm ◽  
Noise Control ◽  
Active Noise Control ◽  
Sound Field ◽  
Secondary Source ◽  
Sound Power ◽  
Control Zone ◽  
Active Noise

When active noise control (ANC) is applied to acquire a ‘quiet zone’, it may produce an increase in the sound power outside the quiet zone and a change in the primary sound field, which are undesirable in anti-detection and personal audio. To obtain a large noise reduction in the control zone and a small increase of sound power outside the control zone, three wideband ANC algorithms are proposed based on the acoustic contrast control (ACC), least-squares (LS), and least-squares with acoustic contrast control (SFR-ACC) algorithms. With a loudspeaker array as the secondary source, dual-zone ANC with directivity, which realizes noise reduction in one zone without changing the sound power in the other zone, is achieved. Compared with the traditional LS algorithm, the three algorithms proposed in this paper can not only realize that the sound power outside the control zone is increased by less than 1 dB, but also reduce the noise in the control zone by more than 10 dB, which provides a new solution to multi-zone ANC research.

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