Single-Frequency Material Characterization Using a Microwave Adaptive Reflect-Array

Personnel screening systems having reconfigurable reflect-arrays at microwave frequencies have been widely used in airports, government buildings, and other facilities to detect potential threats concealed under clothing. In order to reduce the false-alarm of such systems, a dielectric characterization algorithm using a single-frequency is needed. This paper presents a new algorithm, based on Physical Optics, which is capable of characterizing the complex dielectric constant of a security threat. The proposed method derive the geometric and constitutive properties of the threat by minimizing the variance of the modeled and measured fields at 24.16 GHz. Preliminary results show the effectiveness of the proposed method.