Broadband Spatially Feedforward Active Noise Control Algorithms Using a Comb Filter
Author:
Bai Mingsian R.1, Lai Jienwen1
Affiliation:
1. Department of Mechanical Engineering, National Chiao-Tung University, 1001 Ta-Hsueh Rd., Hsin-Chu 300, Taiwan, Republic of China
Abstract
A controller composed of a nonrecursive filter and a recursive filter is used to approximate the ideal controller for a spatially feedforward duct ANC problem. The nonrecursive part represents the dynamics of the transducer, whereas the recursive part is in the form of a comb filter. The parameters of the comb filter are obtained from the impulse response of the controller by using the least-square method. The comb filter is then cascaded with the nonrecursive part implemented as either a fixed filter or an adaptive filter. In the latter approach, two types of LMS-based algorithms are used. The proposed algorithms are implemented on the platform of a digital signal processor. Experimental results showed that the approximated controller attained 17 dB maximal attenuation in the frequency band 200∼600Hz.
Publisher
ASME International
Subject
General Engineering
Reference11 articles.
1. Elliott, S. J., and Nelson, P. A., 1993, “Active Noise Control,” IEEE Signal Process. Mag., 10, pp. 12–35. 2. Fontaine, R. F. La., and Shepherd, I. C., 1983, “An Experimental Study of a Broadband Active Attenuator for Cancellation of Random Noise in Ducts,” J. Sound Vib., 91, pp. 351–362. 3. Swinbanks, M. A.
, 1973, “The Active Control of Sound Propagation in Long Ducts,” J. Sound Vib., 27, pp. 411–436. 4. Kuo, S. M., and Morgan, D. R., 1995, Active Noise Control Systems: Algorithms and DSP Implementations, John Wiley and Sons, New York. 5. Bai, M. R., Lin, Y. J., and Wu, J. D., “Analysis and DSP Implementation of a Broadband Duct ANC System Using Spatially Feedforward Structure,” ASME J. Vibr. Acoust., (to appear).
|
|