An Imaging Operator for a High Speed Holographic Sonar which Uses an Incompletely Orthogonalized Wavefront

  • Yasutaka Tamura
  • Masanobu Takahashi
  • Takao Akatsuka
Part of the Acoustical Imaging book series (ACIM, volume 18)


In this paper, we introduce an imaging operator for a high speed holographic SONAR which uses transmitting pulses modulated with a system of orthonormal functions. This operator is based on a singular value decomposition of the transfer matrix of the digital system. The operator reduces the artifact which emerges when a conventional operator is used. The calculations are simplified using an appropriate model and approximations. The operator obtained can be implemented as multiple filters associated with the directions of view. The point spread function of the 2-D imaging system which uses the pulses modulated by Walsh functions is also demonstrated.


Imaging Operator Acoustical Image Resolution Enhancement Walsh Function Orthonormal Function 
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Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Yasutaka Tamura
    • 1
  • Masanobu Takahashi
    • 1
  • Takao Akatsuka
    • 1
  1. 1.Department of Information EngineeringYamagata UniversityYonezawa 992Japan

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