Open Cassegrain reflector
The reflector can be analyzed using the student version of GRASP9 available from TICRA ( using a Gaussian beam feed antenna.  A step-by-step presentation can be downloaded: open_Cassegrain_ppt_audio with an audio track or open_Cassegrain10_ppt_audio using GRASP10 along with a set of GRASP files: open_Cass_GRASP.  The executable GRANETDOC (Linux version) can be downloaded for the geometry parameters. A set of Fortran subroutines for this geometry is contained in the set: granet_equations.