Date of Award
Doctor of Philosophy
Engineering Science and Mechanics
Anna L. Pate
Source radiation analysis frequently involves characterization or identification of sound sources and fields. In order to effectively perform source radiation analysis, an integrated acoustical imaging system including software and hardware was developed based on spatial transformation. This system utilizes measurements of the complex sound field over a two-dimensional hologram surface with the one-microphone sequential sampling method. Four spatial transformation techniques, i.e. direct convolution, two-dimensional fast Fourier transform, Gauss-Hermite decomposition, and singular value decomposition, were implemented to project the hologram data to desired locations in the three-dimensional space. In addition, four new approaches based on feedback iteration concepts, with the variations of optimization and constraints, were developed to deal particularly with the ill-posed nature encountered in the backward reconstruction of source images;The theoretical background, numerical or experimental investigations, and applicational considerations of the previously mentioned aspects are thoroughly discussed in the dissertation. The conclusions detail the significance of the research results and the future prospects for radiation analysis based on spatial transformation. The technical aspects of the experimental implementation such as a computerized data acquisition system are also included in the appendix.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Mingsian Robin Bai
Bai, Mingsian Robin, "Source radiation analysis based on spatial transformation of acoustic fields " (1989). Retrospective Theses and Dissertations. 8914.