Dissertation
SYMMETRIC AND ASYMMETRIC REVERSIBLE QUASI-HOLOGRAPHIC PROCESSING OF DUAL TRANSDUCER SONAR.
Doctor of Philosophy (PhD), Washington State University
01/2015
Handle:
https://hdl.handle.net/2376/111001
Abstract
Previously, by limiting attention to supersonic-like wave-vectors, time-resolved holographic imaging was found helpful for identifying transient elastic responses of targets contributing to far field scattering [B. T. Hefner \\& P. L. Marston, Acoust. Res. Lett. Online 2, 55-60 (2001)]. That approach was applied to time-evolving three-dimensional wavefields scanned with a two-dimensional raster scan of a hydrophone. Line scan data processed quasi-holographically was determined an alternative to synthetic aperture sonar (SAS) imaging [K. Baik, C. Dudley, \\& P. L. Marston, J. Acoust. Soc. Am. 130, 3838-3851 (2011)]. Quasi-holographic imaging is reversible [D. J. Zartman, D. S. Plotnick, T. M. Marston, \\& P. L. Marston, Proc. Meet. Acoust. 19, 055011 (2013)], allowing isolation of spatial or temporal features and self-normalization. Subsequently, two independent transducers in a side-by-side configuration were used to transmit and/or receive in-phase or out-of-phase with each other. When transmitting, the transducers are driven individually; while receiving, they are separately recorded; giving both monostatic and weakly bistatic data, and allowing post-processing to determine phase relationships. When the transducers were scanned together, glory scattering of a small solid sphere in water was sensitive to different combinations of in-phase and out-of-phase sources/receivers. Certain combinations function as a spatial derivative and may be generated synthetically from scans using a single transducer. Spatial derivative images are highly sensitive to the alignment of a solid cylinder in water. Though transmitting and receiving in-phase improves ordinary SNR, it can reduce some feature sensitivity relative to differential processing. [Supported by ONR.]
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Details
- Title
- SYMMETRIC AND ASYMMETRIC REVERSIBLE QUASI-HOLOGRAPHIC PROCESSING OF DUAL TRANSDUCER SONAR.
- Creators
- David Joseph Zartman
- Contributors
- Philip L Marston (Advisor)Sukanta Bose (Committee Member)Fred Gittes (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Physics and Astronomy, Department of
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Number of pages
- 232
- Identifiers
- 99900581439101842
- Language
- English
- Resource Type
- Dissertation