An Imaging Operator for a High Speed Holographic Sonar which Uses an Incompletely Orthogonalized Wavefront
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.
KeywordsImaging Operator Acoustical Image Resolution Enhancement Walsh Function Orthonormal Function
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