Near-Field Radio Holography of Large Reflector Antennas

Author

Baars, J.W.M. ; Lucas, R. ; Mangum, J.G. ; Lopez-Perez, J.A.

Author_Institution

Max-Planck-lnst. fur Radioastron., Bonn

Volume

49

Issue

5

fYear

2007

Firstpage

24

Lastpage

41

Abstract

We summarize the mathematical foundation of the holographic method of measuring the reflector profile of an antenna or radio telescope. In particular, we treat the case where the signal source is located at a finite distance from the antenna under test, necessitating the inclusion of the so-called Fresnel field terms in the radiation integrals. We assume a "full phase" system with reference receiver to provide the reference phase. We describe in some detail the hardware and software implementation of the system used for the holographic measurement of the 12 m ALMA prototype sub-millimeter antennas. We include a description of the practicalities of a measurement and surface setting. The results for both the VertexRSI and AEC (Alcatel-EIE-Consortium) prototype ALMA antennas are presented.

Keywords

holography; millimetre wave antennas; radiotelescopes; reflector antennas; AEC; ALMA antennas; Alcatel-EIE-Consortium; Fresnel field terms; VertexRSI; full phase system; near-field radio holography; radiation integrals; radio telescope; reflector antennas; sub-millimeter antennas; Antenna measurements; Hardware; Holography; Integral equations; Radio astronomy; Receivers; Reflector antennas; Software measurement; Software prototyping; Testing;

fLanguage

English

Journal_Title

Antennas and Propagation Magazine, IEEE

Publisher

ieee

ISSN

1045-9243

Type

jour

DOI

10.1109/MAP.2007.4395293

Filename

4395293