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Virtual sensing for broadband noise control in a lightly damped enclosure
1Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hunghom, Kowloon, Hong Kong. mmjyuan@polyu.edu.hk
Abstract:
Available virtual sensing schemes either depend on assumptions that are valid for isolated frequencies, or require heavy online adaptations. A simple method is proposed here to predict the virtual signal exactly for broadband noise control in a lightly damped enclosure. The proposed method requires two physical sensors installed judiciously in a sound field to predict a virtual signal. The method is based on an exact mathematical relation between the virtual and physical sensors, which is valid for the entire frequency of interest. It is possible to use multiple sensor-pairs to reduce the sensitivity of the proposed method with respect to acoustic parameters, such as speed of sound or sensor mismatching. Experimental results are presented to verify the analytical results.
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