In this paper, an experimental demonstration employing the decomposition of the time-reversal operator (known as DORT) in combination with pulse inversion is reported, allowing one to detect and selectively focus on nonlinear targets. DORT is a technique based on a multistatic configuration that separates the detected targets by means of eigendecomposition of the time reversal operator allowing for selective transmission of waves towards a target of interest. Pulse inversion is a technique that enhances harmonic responses while suppressing fundamental responses. By applying DORT with pulse inversion (PIDORT), harmonic detection and selective transmission to detected nonlinear targets can be enhanced. The results from our experiment show that PI-DORT can effectively detect and separate nonlinear targets for selective transmission.
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