Microwave Imaging Enhanced by Duplexed Random Phase Modulations

Microwave imaging under the illumination of randomized fields has demonstrated promising potential. Recent results showed that based on a phase-reconfigurable frequency-selective surface (PFSS), a cost-effective 24-GHz imager can be implemented, showing a wavelength-scale resolution. In this work, we further improve this imager by realizing duplexed random phase modulations. Numerical and experimental results showed that based on the same PFSS, the proposed duplex imager can significantly increase the number of available independent measurements (AIMs) and the sensing capacity. As the result, the error of the reconstructed image can be reduced by 49%, and the imaging resolution reaches 6.25 mm, that is, a half wavelength at 24 GHz. The aperture of the proposed duplex imager can be conveniently extended, exhibiting a promising potential in low-cost security scanning applications, especially for large objects such as human bodies.