Designing axially symmetric Cassegrain or Gregorian dual-reflector antennas from combinations of prescribed geometric parameters

A procedure to design axially symmetric Cassegrain or Gregorian dual-reflector antennas from various combinations of prescribed geometric parameters is presented. From these input parameters, the overall geometry of the antenna is derived in closed form. This procedure can be used as the starting point of a synthesis procedure, where both main reflector and subreflector are shaped to create the desired aperture field distribution.