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Distribution theory approach to implementing directional acoustic sensors
1Department of Electrical and Computer Engineering, University of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, Massachusetts 02747-2300, USA.
The Journal of the Acoustical Society of America
|January 12, 2010
Summary
This study introduces a novel method using distribution theory to estimate acoustic pressure derivatives for directional sensors. This enables a multichannel filter for improved spatial and temporal filtering in compact acoustic sensing applications.
Area of Science:
- Acoustics
- Signal Processing
- Sensor Technology
Background:
- Directional acoustic sensors aim for high directivity in small spaces.
- Directly measuring acoustic pressure derivatives is challenging.
- Existing indirect methods include finite-difference approximations using pressure sensors.
Purpose of the Study:
- To derive an indirect method for estimating spatial partial derivatives of acoustic pressure using distribution theory.
- To construct a multichannel filter for processing acoustic pressure signals.
- To develop a discrete-spatial version of the multichannel filter.
Main Methods:
- Utilizing the theory of distributions to derive a novel method for pressure derivative estimation.
- Constructing a multichannel filter employing 3D integral transforms.
- Applying a lowpass Gaussian temporal filter with bandwidth inversely proportional to epsilon.
- Employing the lattice method for numerical multiple integration to create a discrete-spatial filter.
Main Results:
- The derived method provides an indirect approach to estimate spatial partial derivatives of acoustic pressure.
- A multichannel filter was constructed, processing acoustic pressure via 3D integral transforms.
- The filter outputs a spatially and temporally filtered pressure signal at the origin.
- A discrete-spatial version of the multichannel filter was developed.
Conclusions:
- The theory of distributions offers an effective indirect method for estimating acoustic pressure derivatives.
- The developed multichannel filter enhances spatial and temporal filtering for acoustic sensing.
- The discrete-spatial filter is suitable for practical implementation in compact directional acoustic sensors.
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