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Title: Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization

Abstract

This paper evaluates the performance of various regularization parameter choice methods applied to different approaches of nearfield acoustic holography when a very nearfield measurement is not possible. For a fixed grid resolution, the larger the hologram distance, the larger the error in the naïve nearfield acoustic holography reconstructions. These errors can be smoothed out by using an appropriate order of regularization. This study shows that by using a fixed/manual choice of regularization parameter, instead of automated parameter choice methods, reasonably accurate reconstructions can be obtained even when the hologram distance is 16 times larger than the grid resolution.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE) - Office of Building Technologies
OSTI Identifier:
1389827
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the Acoustical Society of America; Journal Volume: 140; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Chelliah, Kanthasamy, Raman, Ganesh G., and Muehleisen, Ralph T. Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization. United States: N. p., 2016. Web. doi:10.1121/1.4954757.
Chelliah, Kanthasamy, Raman, Ganesh G., & Muehleisen, Ralph T. Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization. United States. doi:10.1121/1.4954757.
Chelliah, Kanthasamy, Raman, Ganesh G., and Muehleisen, Ralph T. 2016. "Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization". United States. doi:10.1121/1.4954757.
@article{osti_1389827,
title = {Enhanced nearfield acoustic holography for larger distances of reconstructions using fixed parameter Tikhonov regularization},
author = {Chelliah, Kanthasamy and Raman, Ganesh G. and Muehleisen, Ralph T.},
abstractNote = {This paper evaluates the performance of various regularization parameter choice methods applied to different approaches of nearfield acoustic holography when a very nearfield measurement is not possible. For a fixed grid resolution, the larger the hologram distance, the larger the error in the naïve nearfield acoustic holography reconstructions. These errors can be smoothed out by using an appropriate order of regularization. This study shows that by using a fixed/manual choice of regularization parameter, instead of automated parameter choice methods, reasonably accurate reconstructions can be obtained even when the hologram distance is 16 times larger than the grid resolution.},
doi = {10.1121/1.4954757},
journal = {Journal of the Acoustical Society of America},
number = 1,
volume = 140,
place = {United States},
year = 2016,
month = 7
}
  • This paper evaluates the performance of various regularization parameter choice methods applied to different approaches of nearfield acoustic holography when a very nearfield measurement is not possible. For a fixed grid resolution, the larger the hologram distance, the larger the error in the naive nearfield acoustic holography reconstructions. These errors can be smoothed out by using an appropriate order of regularization. In conclusion, this study shows that by using a fixed/manual choice of regularization parameter, instead of automated parameter choice methods, reasonably accurate reconstructions can be obtained even when the hologram distance is 16 times larger than the grid resolution.
  • An experimental comparison of four different methods of nearfield acoustic holography (NAH) is presented in this study for planar acoustic sources. The four NAH methods considered in this study are based on: (1) spatial Fourier transform, (2) equivalent sources model, (3) boundary element methods and (4) statistically optimized NAH. Two dimensional measurements were obtained at different distances in front of a tonal sound source and the NAH methods were used to reconstruct the sound field at the source surface. Reconstructed particle velocity and acoustic pressure fields presented in this study showed that the equivalent sources model based algorithm along withmore » Tikhonov regularization provided the best localization of the sources. Reconstruction errors were found to be smaller for the equivalent sources model based algorithm and the statistically optimized NAH algorithm. Effect of hologram distance on the performance of various algorithms is discussed in detail. The study also compares the computational time required by each algorithm to complete the comparison. Four different regularization parameter choice methods were compared. The L-curve method provided more accurate reconstructions than the generalized cross validation and the Morozov discrepancy principle. Finally, the performance of fixed parameter regularization was comparable to that of the L-curve method.« less
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