A note on painted reflecting surfaces

The microwave depolarization arising in the process of oblique reflection from a painted surface has been found insensitive to the dielectric constant of the paint and is not negligible for higher microwave frequencies if the polarization requirement is very stringent; the calculated cross polarization of a 19-GHz example agrees with the measured result. The approximate reflection coefficients also suggest lenient tolerance for the uniformity of the paint layer on reflector antennas of large ratio.