Design Of Noise Control Systems Research Articles

Investigation on the performance of an active noise control window system mounted on the top-hung window of a residential room

Urban noise mitigation experiment through active noise control window is not commonly carried out in in situ urban setting. This paper outlines our experimental settings of performing active noise control across the open aperture of the top-hung window frame in a dormitory room. A multi-channel adaptive filtered-x least mean square method is implemented in real-time. Experiments and analyses are carried out to investigate how the noise reduction performance of this active noise control window system is affected by the number of reference microphones, the distance between reference microphones and secondary sources, and the distributions of error microphones under practical restrictions of the real system implementation. Variation of the secondary path estimation is another important consideration in active noise control system design. Real-time experiments are carried out to investigate the sensitivity of the ANC window system over the secondary path variation caused by varying window opening status, and whether a generalised secondary path measured in one window opening setting can be applied to other window opening conditions.

Optimal parametric design of delayless subband active noise control system based on genetic algorithm optimization

Active noise control systems are generally application-specific, and an appropriate algorithm with an optimal configuration is desirable in the first stage of active noise control system design and deployment. This study presents a design of the subband active noise control system with optimal parameters for a practical broadband active noise control. Although the delayless subband active noise control has gained wide attention for broadband noise cancellation, an optimal design remains a challenge because of the complex interplay between multiple factors such as spectral leakage, delay and weight stacking distortion subject to a number of configurable parameters, and weight stacking method. The configurable parameters can hardly be optimized independently because the active noise control performance depends on the combined configuration. A simple near black box active noise control algorithm optimization model is thus established by incorporating the genetic algorithm optimization into the parametric design of the delayless subband algorithm. The automated process does not require an understanding of the performance characteristics for different parameters. The significance of applying the automated genetic algorithm optimization to the complex multiparameter nonlinear active noise control design is revealed by numerical simulations, particularly for the multichannel low-frequency broadband active noise control system configured with the delayless subband algorithms. This provides a way for the optimal parametric design of subband active noise control before being used in a practical complex scenario.

Sustainable noise control system design for building ventilation systems

This article presents an integral approach to sustainable noise control system design for building ventilation systems in Hong Kong. This approach combines the analytic hierarchy process and life cycle analysis (LCA) to obtain a holistic view of the system performance in terms of human, economic, and environmental impacts. The approach was applied to the evaluation of various noise control systems including duct liners, silencers, semi-active noise control, and active noise control for ventilation systems. Although passive systems such as duct liners and silencers seem to consume more material resources than semi-active and active systems, the latter require sensors, controllers, resonators or loudspeakers, and electricity. In fact, the LCA showed little difference between the semi-active and active systems and the passive systems in term of resource depletion and carbon emission. As human impact and economic impact dominated the experts’ views on sustainability, the analysed results indicated that the most sustainable design was duct liners, followed by silencers, active noise control, and semi-active noise control.

MIMO Noise Control System Design by Using Subband-based Partial Model Matching on Frequency Domain

In this paper, a practical method to design a noise reduction controller is proposed. In this method frequency domain of interest is divided into subbands taking frequency response of noise into account. And on each subband, it is proposed that the controller is tuned based on partial model matching on frequency domain. The proposed method is practical since it requires only input-output data for the tuning process instead of identified mathematical model of the plant. In order to show validity of the method, it was applied to an actual room with a stereo audio system. The experimental result shows that the proposed controller designed succeeded 45% attenuation of multiple peak noise.