Microwave-Induced Thermoacoustic Imaging for Embedded Explosives Detection in High-Water Content Medium

Improvised explosive devices (IEDs) have always been a major threat to personnel safety with continuous evolutions and new variants. Traditional methods for detecting IEDs, such as X-ray, have some drawbacks, so safe and efficient new detection techniques are highly desired. Microwave-induced thermoacoustic imaging (MITAI), being widely investigated for biomedical applications, is a promising candidate for detecting explosives embedded in high-water content materials due to its intrinsic advantages of nonionizing radiation, high contrast, and easy imaging procedure. Proof-of-concept demonstration is theoretically and experimentally carried out by successful detection of an explosive surrogate sample immersed in water. Good accordance between the experimental and simulation results validates the effectiveness of this approach. A parametric study of some key parameters is then performed to investigate their impact on detection efficiency and to evaluate the performance of a practical MITAI system for explosive detection.