High-resolution air-coupled ultrasound imaging of small objects using filtered back-projection based on cross-correlation

High-resolution acoustic imaging in air is traditionally constrained by the need for bulky multi-channel microphone arrays, limiting its applicability to small objects and confined environments. This study introduces a novel Joint Cross-Correlation and Filtered Back-Projection (JCCFBP) algorithm that enables high-resolution imaging using only a single microphone. The method combines cross-correlation for range profiling with filtered back-projection for image reconstruction, effectively capturing fine spatial details without distinguishing between near-field and far-field conditions. Experimental validation using a custom bionic sonar setup demonstrates the algorithm’s capability to image small objects in air with high accuracy and robustness against environmental noise. The proposed approach offers a compact, efficient, and scalable solution for acoustic imaging in constrained scenarios.