Masking property based microphone array post-filter design

An experienced technician can usually identify the cutting condition by hearing the sound generated during the cutting and the sound signal can be expected to detect the features closely related to the tool condition. However, the background noise always contaminates the signal obtained by microphone system during cutting and reduces the chance of applying the sound based micro tool condition monitoring system in industry. In order to reduce the noise effect and improve the system performance, a microphone array integrated with Wiener filter was designed and implemented in this study to enhance the noise reduction capability for monitoring system. The experimental results show that the microphone array integrated with Wiener filter provides a better solution than single microphone integrated with Wiener filter or the microphone array without the post filter design in reducing the broadband background noise.

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Post-Filter Design for Superdirective Beamformers with Closely Spaced Microphones

2007 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics ◽

10.1109/aspaa.2007.4393032 ◽

2007 ◽

Cited By ~ 8

Author(s):

Heinrich W. Lollmann ◽

Peter Vary

Keyword(s):

Filter Design ◽

Post Filter

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Two-Dimensional FIR Filter Design on Wideband Speech Enhancement in Microphone Array

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.39.260 ◽

2010 ◽

Vol 39 ◽

pp. 260-266

Author(s):

Xiao Fei Su ◽

Xin Hong Zhang

Keyword(s):

Speech Enhancement ◽

Filter Design ◽

Microphone Array ◽

Fir Filter ◽

Beam Forming ◽

Pass Band ◽

Two Dimensional ◽

Sound Environment ◽

Fir Filter Design ◽

Suppress Noise

Due to complexity of sound environment, the performance of speech enhancement is degraded greatly based on traditional beam-forming when directivity of arrival of sound and number of sound are not been estimated precisely. In this paper, according to characteristics of handle-communicated equipment, a method on suppression of environmental noise and disturbance is provided. Beam-forming on speech wideband in desired angle is realized by designing a two-dimensional FIR filter which has fan structure in pass-band and wedge-shaped structure in transition-band. The filter can suppress noise and disturbance out of main-lobe desired. The simulations demonstrated that the filter designed is effective.

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