The 1.4-m Telescope for the Q/U Imaging Experiment

Author

Imbriale, William A. ; Gundersen, Joshua ; Thompson, Keith L.

Author_Institution

Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA

Volume

59

Issue

6

fYear

2011

fDate

6/1/2011 12:00:00 AM

Firstpage

1972

Lastpage

1980

Abstract

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.

Keywords

electromagnetic wave polarisation; optical images; radiofrequency cosmic radiation; radiotelescopes; reflector antenna feeds; Dragonian side-fed geometry; Q-band frequency; Q/U imaging experiment; RF optics; W-band frequency; antenna feed; concave hyperboloidal subreflector; corrugated platelet feed horn array; cosmic microwave background; cross-polarization; focal length; optical design; paraboloidal main reflector; telescope; Arrays; Detectors; Feeds; Geometry; Mirrors; Telescopes; Corrugated horns; platelet arrays; radio telescope; wide scanning reflector antenna;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/TAP.2011.2123864

Filename

5725168