Unpolarized sources that generate highly polarized fields outside the source

It is demonstrated that an unpolarized primary electromagnetic source may, under special conditions, produce a field outside the source domain that is almost completely polarized in nearly all directions. This result demonstrates that the polarization statistics of a random electromagnetic field may differ significantly from the polarization statistics of the source distribution that generates it, and may in fact be quite different in different directions of observation. An example of such a source is given.