Extended depth-of-field imaging employing integrated binary phase pupil mask and principal component analysis image fusion.

The imaging depth of field (DOF) of white-light illuminated objects is extended by carefully integrating two image-processing techniques, one optical and one digital. The optical technique makes use of a tailored phase mask positioned at the pupil of the imaging system to cause different color channels to have different focal lengths; accordingly, the phase-mask equipped imaging system acquires a high resolution and reasonably focused image in at least one of the three, red, green, blue (RGB), color channels at any location within the specified DOF. The digital processing comprises fusing the separate RGB images with an original technique that implements principal component analysis to deliver the overall sharpest grayscale composite image throughout the DOF region.

Millimeter Wave High Resolution Radar Accuracy in Fog Conditions-Theory and Experimental Verification.

Attenuation and group delay effects on millimeter wave (MMW) propagation in clouds and fog are studied theoretically and verified experimentally using high resolution radar in an indoor space filled with artificial fog. In the theoretical analysis, the frequency-dependent attenuation and group delay were derived via the permittivity of the medium. The results are applied to modify the millimeter-wave propagation model (MPM) and employed to study the effect of fog and cloud on the accuracy of the Frequency-Modulated Continuous-Wave (FMCW) radar operating in millimeter wavelengths.