Velocity-Based Nearfield Acoustic Holography

  • M. Robin Bai
  • Anna L. Pate
Part of the Acoustical Imaging book series (ACIM, volume 16)


Numerical investigations of nearfield acoustic holography in a contaminated acoustic field were performed. In this study, a baffled piston vibrating at low frequencies was chosen as the primary source. In addition, two types of disturbing sources were also considered. These sources were monopoles and plane waves propagating either perpendicularly or parallel to the hologram plane. Because pressure-based nearfield holography (PBNAH) was quite sensitive to the disturbing sources, a new method called velocity-based nearfield holography (VBNAH) was developed. The backpropagation images of the baffled piston obtained by using the VBNAH technique were compared to the images provided by the PBNAH technique. In the presence of the disturbing sources, VBNAH provided, in general, significantly better images than PBNAH. Errors caused by the disturbing sources depended on the type of those sources and their location with respect to the hologram plane.


Particle Velocity Acoustic Field Velocity Magnitude Holography Technique Partical Velocity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. 1.
    H. M. Smith, “Principles of Holography,” Wiley-Interscience, New York (1969).Google Scholar
  2. 2.
    J. D. Maynard, E. G. Williams, and Y. Lee, Nearfield acoustic holography: I. Theory of generalized holography and the development of NAH, J. Acoust. Soc. Am., Vol. 78, No. 4 (1985).CrossRefGoogle Scholar
  3. 3.
    D. Dudgeon and R. M. Mersereau, “Multidimensional Digital Signal Processing,” Prentice-Hall, Inc., pp. 359–363 (1984).MATHGoogle Scholar
  4. 4.
    A. L. Pate and R. M. Bai, One-microphone sound intensity method, J. Acoust. Soc. Am., Suppl. 1, Vol. 80 (1986).Google Scholar
  5. 5.
    M. R. Bai and A. L. Pate, Experimental investigations of acoustic field based on one-microphone, sequential sampling technique, submitted for publication in Transactions of ASME (1987).Google Scholar
  6. 6.
    W. A. Veronesi and J. D. Maynard, Nearfield acoustic holography (NAH) II. Holographic reconstruction algorithms and computer implementation, J. Acoust. Soc. Am., Vol. 81, No. 5 (1987).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • M. Robin Bai
    • 1
  • Anna L. Pate
    • 1
  1. 1.Department of Engineering Science and MechanicsIowa State UniversityAmesUSA

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