Recent progress in reflector antenna analysis & design

The latter part of the 20th century has seen significant changes and improvements in the design and practice of reflectorantennas. As well as traditional users of reflectors, such as defence, telecommunication utilities and radio astronomy, significant consumer markets have now opened up. For instance, it is common for many homes and offices to have a dish connected to a wall or roof. At the same time design techniques for reflectors and associated feed systems have also undergone change. Until a few years ago effectsthat were poorly modelled or completely ignored that can now be analysed include, reflectoredge diffraction, near-field effects, grid, composite and painted surfaces, accurate feed models, mutual coupling and scattering in feed arrays, and reflector/feedinteractions. Shaped reflectors are now widely used on satellite antennas, and dielectric-loaded horns are replacing corrugated horns in some earth station applications. It is the purpose here to outline some recent changes and improvements in the design and synthesis techniques used for reflectors and feeds.