Maximum Entropy Multi-Resolution EM Tomography by Adaptive Subdivision

  • Li-He Zou
  • Zhengrong Wang
  • Louis E. Roemer
Conference paper
Part of the Fundamental Theories of Physics book series (FTPH, volume 70)


Audio band electromagnetic (EM) waves have a great potential for success in bore hole to bore hole or surface to bore hole tomography for geophysical exploration or environmental tests. Low resolution is generally the major limitation in the EM tomography. If a high resolution is sought, many artifacts with random patterns will show in the resultant image of the reconstruction if a least square error criterion is applied. The maximum entropy constraint can certainly reduce the artifacts. However, the conflict of high resolution and fewer artifacts still exists. This paper proposes an adaptive procedure which produces a tomography image with different resolution in different subdivisions according to the details the subdivision may possess. This procedure can reduce unnecessary resolution in those areas where no more interesting details are shown while showing high resolution in other areas where interesting details may occur. Thus, the artifacts can be reduced to a minimum. Computer simulations on the proposed method compared with least square error method and a conventional maximum entropy method show that the proposed method can produce higher resolution images with significantly reduced artifacts. All experimental results are encouraging and show great potential in practical applications.


Maximum Entropy Tomographic Image Maximum Entropy Principle Interesting Detail Adaptive Subdivision 
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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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Li-He Zou
    • 1
  • Zhengrong Wang
    • 1
  • Louis E. Roemer
    • 1
  1. 1.Department of Electrical EngineeringLouisiana Tech UniversityRustonUSA

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