Localizing Perturbed Objects in a Room with Reflective Boundaries Using Dispersed Acoustic Measurements

Abstract

In the field of acoustics, much work has been done to extensively research the localization of perturbations in a multiple scattering medium. One of the most popular methods for perturbation localization is time-reversal, which is the process of using sensors to receive an acoustic wave and send it back toward the source in reversed time order. It has been shown that perturbations can also be localized without a priori knowledge of the scattering medium by subtracting baseline from perturbation acoustic pressure field measurements and applying time-windowing to localize the perturbation. However, the localization of perturbations using pressure field subtraction and time-windowing breaks down in environments where the acoustic path to the perturbations is not well-known due to a lack of information about either the distribution of the scatterers or geometry of the environment. In this study, both pressure field subtraction and time-reversal are used to localize hidden perturbations in a complex reverberant environment by utilizing a sparse sensor grid placed throughout the medium. This research aims to utilize distributed acoustic sensors in areas where optical camera systems may not be able to be utilized by analyzing the acoustic propagation of the time-reversed signal on the sparse sensor array (LA-UR-20-29698).