[Doc Ewen looks into the horn antenna, 1950]
Image courtesy of Doc Ewen


Harvard Cyclotron: 1948-1951

Detection of HI Line: 1951

Harvard 24ft and 60ft and NRAO founding: 1952-1956

1950s and 1960s: Two Roads that Crossed

Microwave & Millimeter Wave Applications in the 1970s and 1980s

Mm Wave Radiometry in the 1990s

May 2001 visit to NRAO Green Bank



[Doc Ewen and horn antenna, 2001]
Image courtesy of Doc Ewen

Doc Ewen: The Horn, HI, and Other Events in US Radio Astronomy

by Doc Ewen, © 2003

Slide 22: Microwave and Millimeter Wave Applications in the 1970s and 1980s

[Cassegrain antenna with motor-driven subreflector]

Sketch of Cassegrain antenna and signal path components at entrance to GOMUX. A Gaussian optics frequency multiplexer (GOMUX) separates the 30-110 GHz signal into 8 contiguous bands, each having a 10 GHz bandwidth. After the wideband beam is focused by the Cassegrain antenna to a beam waist at the secondary focal point, the beam is repeatedly refocused by a series of solid or perforated ellipsoidal mirrors. The solid ellipsoidal mirrors and one flat mirror are used in the input chain to the GOMUX Credit: Photo courtesy of Doc Ewen.

Slide 23
Modified on Wednesday, 02-Feb-2005 11:45:14 EST by Ellen Bouton