Statistical Stability in Time Reversal

@article{Papanicolaou2004StatisticalSI,
  title={Statistical Stability in Time Reversal},
  author={George C Papanicolaou and Knut S{\o}lna and Leonid Ryzhik},
  journal={SIAM J. Appl. Math.},
  year={2004},
  volume={64},
  pages={1133-1155}
}
When a signal is emitted from a source, recorded by an array of transducers, time-reversed, and re-emitted into the medium, it will refocus approximately on the source location. We analyze the refocusing resolution in a high frequency remote-sensing regime and show that, because of multiple scattering in an inhomogeneous or random medium, it can improve beyond the diffraction limit. We also show that the back-propagated signal from a spatially localized narrow-band source is self-averaging, or… 

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