  We describe and demonstrate a technique for correcting direction dependent
artifacts due to asymmetries in antenna patterns and differences among antennas
used in radio interoferometric imaging. The technique can correct images in all
Stokes parameters I, Q, U and V and is shown with simulated data to reduce the
level of artifacts to near the level of those from the basic imaging technique.
The demonstrations use simulations of a mixed array of 13.5 and 15 m antennas
with asymmetric patterns. The flux densities and spectral indices of the
sources in a high dynamic range realistic simulated sky model are well
recovered. Source polarization properties are also recovered in tests using
unpolarized and partly polarized sources. The additional computational run time
for Stokes I correction is about 50\% in a realistic test described.
