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Author(s): C. Yeh (corresponding author) [1]; F. Shimabukuro [1, 2]; P. Stanton [1]; V. Jamnejad [1]; W. Imbriale [1]; F. Manshadi [1] Following the discovery by Kao and Hockman [1, [...]

A wideband Radio Telescope was designed and built for use in the Goldstone Apple Valley Radio Telescope (GAVRT) program. It uses an existing 34-m antenna retrofitted with a tertiary offset mirror placed at the vertex of the main reflector. It can be rotated to allow using two feeds that cover the 0.5-14-GHz band. The feed for 4.0-14.0 GHz is a cryogenically cooled, commercially available, open-boundary quadridge horn from ETS-Lindgren. Coverage from 0.5 to 4.0 GHz is provided by an uncooled lower frequency version of the same feed that uses a cooled LNA. The measured aperture efficiency is greater than 40% over much of the band. [ABSTRACT FROM AUTHOR]

The optical design of the 1.4-m telescope for the Q/U Imaging ExperimenT (QUIET) is described. The telescope is intended to image the polarization of the cosmic microwave background (CMB) with detectors at two frequencies (Q- and W-band) with unprecedented sensitivity. The RF optics uses a classical Dragonian side-fed geometry that employs a paraboloidal main reflector illuminated by a concave hyperboloidal subreflector. The relatively large offset distance and focal length of the main reflector, and the avoidance of caustics between the two reflectors, yield relatively flat reflectors with very low cross-polarization and a wide field of view capability. The antenna is fed by either a 91-element W-band or a 19-element Q-band corrugated platelet feed horn array. The telescope is installed on the CBI platform in Chile, and data taking is underway. [ABSTRACT FROM AUTHOR]

Addresses the power-loss problem when more than one mode in simultaneously present in waveguide in power plants. Reference to the concept of expressing power loss along a given uniform waveguide in nepers/meter for a multimode waveguding system with finite wall conductivity; Detailed information on the formulas.

Presents a study which discussed a numerical approach to solving the problems of synthesis of dual-shaped offset reflector antennas. Details of the numerical approach to the problem; Illustration of numerical results; Discussion.