Axial cross polarization in reflector antennas with surface imperfections

Expressions for the probability density function and mean of boresight cross polarization field intensity in terms of the rms surface error
\epsilon
are derived. It is shown that for small errors the mean on-axis cross polarization field intensity is directly proportional to the rms surface error. For relatively large errors (
\epsilon > 0.04 \lambda
) forward cross polarization is proportional to the square root of (
1 - exp (-2\sigma^{2})
) where
\sigma
is the rms phase error. It is also shown that forward cross polarization is proportional to the correlation diameter and is a function of the polarization efficiency. Experimental measurements are revealed and results are compared with theoretical findings.