100-GHz measurements of two astigmatic launchers.

Astigmatic launchers that would permit a single earth station antenna to communicate with all the satellites along the geo- synchronous arc have been fabricated and measured at a frequency of 100 GHz. These astigmatic launchers maintain constant beamwidth in the two principal planes as their phase center separations vary as a function of the length of the parallel plates used in the arrangements. Good agreement between measured data and calculated values has been obtained for astigmatic corrections required by feeds displaced 18 and 29 degrees from the focus.