Improved Time-of-Flight Estimation Method for Acoustic Tomography System

Tomographic imaging based on acoustic wave time-of-flight (TOF) measurement is considered to be a promising technique for monitoring temperature fields due to it being noninvasive, relatively low cost, having a high temporal resolution, and being easy to use. Accurate estimation of the TOF is key in improving the quality of the reconstructed images. In this paper, an improved TOF estimation method based on the Akaike information criterion (AIC) is developed. Two improvements are studied in comparison to the conventional weighted AIC TOF estimation methods against crosstalk interference and sound reflections: an adaptive window is applied for accurate AIC TOF estimation; a phase correction method is used to further improve the temporal resolution and noise robustness of the TOF estimation. The feasibility and effectiveness of the developed methods are validated in two experiments.