Browsing by Author "Hu, Jwusheng"

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Adaptive Feedforward Active Noise Cancellation in Ducts Using the Model Matching of Wave Propagation Dynamics
(2012-09-01)
Hu, Jwusheng
;
Hsiao, Tesheng
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電機工程學系
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Department of Electrical and Computer Engineering
Active noise cancellation in ducts using multiple feedforward sensors have been investigated by many researchers. When adaptive algorithms were applied, usually a lumped parameter model was assumed and the model includes the dynamics of the duct, sensors and actuators (e.g., microphone and loudspeaker). The distributed nature of the duct usually leads to a large parameter space and is difficult to implement direct adaptive control. This brief presents a control architecture which separates the duct's dynamics from those of sensors and actuators. An adaptive control algorithm is proposed to cope with the unknown dynamics of sensors and actuators. Experiments were conducted to show the effectiveness of the control law.
Speech Enhancement for Mobile Phones Based on the Imparity of Two-Microphone Signals
(2009)
Hu, Jwusheng
;
Lee, Mingtang
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電控工程研究所
;
Institute of Electrical and Control Engineering
In this paper, we consider a speech enhancement system for mobile phones using pair microphones. The locations of the two microphones are arranged to facilitate the derivation of speech absence probability. The results are substituted into an MMSE estimator in loudness domain for speech purification. Compared with the conventional algorithms [1, 2], which estimate the speech absence probability based on a single microphone, the proposed method does not require many empirical parameters and is relatively robust under different types of noises. The performance of this method is evaluated under noisy environments with music and car noises.