Spacecraft Antenna Design using Optimisation

The design of shaped-beam antennas suitable for satellite broadcasting and satellite communication is described. The method employs an optimisation search routine in which the reflector shape is varied and the antenna far-field is compared at sample points to the desired far-field. Three examples are given corresponding to the CONDOR, EUTELSAT 2 and AFSAT Satellites. In the latter it is found that two feeds are needed in order to meet the specification and their excitation is included in the search in addition to the reflector shape. As far as is known this is the first time a shaped reflector and a small array have been used together to meet intricate pattern requirements.