Some reflector and feed antenna inventions that made a difference: Fundamentals and examples from radio telescopes, satellite communications and radio links

The paper will review some inventions within reflector antennas and feeds that represented a large step forward when they were introduced, in terms of both performance and industrial or scientific usefulness. The fundamental design principles as well as the actual solutions will be overviewed in a simple manner. The overview covers dipole-disk with ring for ship Earth stations, corrugated horns, hat-fed antennas for radio links, and wideband log-periodic "eleven" feed for SKA and VLBI 2010 radio telescopes. The inventions can in all cases be associated with simple fundamental EM principles, and an improvement of a fundamental subefficiency. © 2013 IEEE