Selective focusing in multiple-target media: the transfer matrix method
- 1 January 1993
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 1139-1142 vol.2
- https://doi.org/10.1109/ultsym.1993.339588
Abstract
The iterative time reversal mirror provides an elegant way of focusing in a multiple-target media on the most reflective one. This paper presents a method to focus on the other targets. This method is derived from the theoretical study of the iterative time reversal process. It relies on both the definition of transfer matrix K of the system (array of transducers+medium of interest) and the introduction of the time reversal operator K*K. It is shown that, in the case of well-resolved targets of different reflectivities, each target corresponds to one eigenvector of K*K. This eigenvector provides the optimum delay law to focus on the associated target. The principle is to measure K, to calculate the eigenvectors of K*K and to transmit one eigenvector in order to focus on the corresponding target. An experimental validation of the method is givenKeywords
This publication has 2 references indexed in Scilit:
- The iterative time reversal process: Analysis of the convergenceThe Journal of the Acoustical Society of America, 1995
- The iterative time reversal mirror: A solution to self-focusing in the pulse echo modeThe Journal of the Acoustical Society of America, 1991