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Time-reversal and MUSIC. Anthony J. Devaney Department of Electrical and Computer Engineering Northeastern University Boston, MA 02115 email: [email protected]. Review of time-reversal Discussion of Vector Spaces Incorporation of MUSIC Computer Simulations. System Configuration. - PowerPoint PPT Presentation
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04/22/23 A.J. Devaney Stanford Lecture III 1
Time-reversal and MUSIC
Anthony J. DevaneyDepartment of Electrical and Computer Engineering
Northeastern UniversityBoston, MA 02115
email: [email protected]
Review of time-reversalDiscussion of Vector Spaces
Incorporation of MUSICComputer Simulations
04/22/23 A.J. Devaney Stanford Lecture III 2
System Configuration
Antenna Array
Antenna element
Point Scatterers
Assumes Born Approximation
04/22/23 A.J. Devaney Stanford Lecture III 3
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Incident Wavefield
04/22/23 A.J. Devaney Stanford Lecture III 4
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Scattered Wavefield--Born
04/22/23 A.J. Devaney Stanford Lecture III 5
Receive Voltage
04/22/23 A.J. Devaney Stanford Lecture III 6
Time-Reversal Matrix
04/22/23 A.J. Devaney Stanford Lecture III 7
Array Point Spread Function
Backpropagated field from scatterer located at Xm’ evaluated at field location r
04/22/23 A.J. Devaney Stanford Lecture III 8
Well-resolved Targets
Backpropagated field from scatterer located at Xm’ vanishes at all other scatterer locations
04/22/23 A.J. Devaney Stanford Lecture III 9
Vector Spaces for W.R.T.
Signal Subspace Noise Subspace
04/22/23 A.J. Devaney Stanford Lecture III 10
Focusing with Time-reversal
04/22/23 A.J. Devaney Stanford Lecture III 11
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Focused versus time-reversed fields
04/22/23 A.J. Devaney Stanford Lecture III 12
Non-well Resolved Targets
04/22/23 A.J. Devaney Stanford Lecture III 13
MUSIC
Pseudo-Spectrum
04/22/23 A.J. Devaney Stanford Lecture III 14
Computer Simulation
Future Directions• Extended Objects• Random Media• Sparse Arrays
04/22/23 A.J. Devaney Stanford Lecture III 15
Pseudo-spectrums
04/22/23 A.J. Devaney Stanford Lecture III 16
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Contour plots of Pseudo-spectrums
