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A Broadband—Holography Imaging System for Nondestructive Evaluation

  • G. Prokoph
  • H. Ermert
  • M. Kröning
Part of the Acoustical Imaging book series (ACIM, volume 15)

Abstract

Acoustical Holography has become a powerful means in computerized non-destructive testing. To obtain a good axial resolution the conventional monofrequent concept /1/ was extended to Multifrequency Holography /2/. Here the data-acquisition has to be repeated several times using a series of different frequencies. A further step is to excite the system with broadband signals, to obtain the object information over a certain range of frequencies within a single measurement procedure. This leads to the principle of “Broadband Holography”, a reconstruction scheme, which is similar to. the well known LSAFT algorithm /3/.

Keywords

Inverse Filter Object Area Transmitted Waveform Acoustical Holography Finite Impulse Response Digital Filter 
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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References

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    Langenberg, K. J., Berger, M., Kreutter, Th., Mayer, K., Schmitz, V., SAFT Signal Processing, Preprint of a paper to be published in NDT International,(1986).Google Scholar
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    Papoulis, A., Signal Analysis, McGraw Hill, New York (1977).Google Scholar
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    Nagai, K., Multifrequency Acoustical Holography Using a Narrow Pulse, IEEE Transactions on Sonics and Ultrasonics, SU-31:3, pp 151–156, (May 1984).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • G. Prokoph
    • 1
  • H. Ermert
    • 1
  • M. Kröning
    • 2
  1. 1.Department of Electrical EngineeringUniversity of Erlangen-NurembergErlangenGermany
  2. 2.Kraftwerk-Union AGErlangenGermany

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