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arXiv · 1210.0506

A wide-band, active antenna system for long wavelength radio astronomy

Brian C. Hicks·Nagini Paravastu-Dalal·Kenneth P. Stewart·William C. Erickson·Paul S. Ray·Namir E. Kassim·Steve Burns·Tracy Clarke·Henrique Schmitt·Joe Craig·Jake Hartman·Kurt W. Weiler
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Abstract

We describe an "active" antenna system for HF/VHF (long wavelength) radio astronomy that has been successfully deployed 256-fold as the first station (LWA1) of the planned Long Wavelength Array. The antenna system, consisting of crossed dipoles, an active balun/preamp, a support structure, and a ground screen has been shown to successfully operate over at least the band from 20 MHz (15 m wavelength) to 80 MHz (3.75 m wavelength) with a noise figure that is at least 6 dB better than the Galactic background emission noise temperature over that band. Thus, the goal to design and construct a compact, inexpensive, rugged, and easily assembled antenna system that can be deployed many-fold to form numerous large individual "stations" for the purpose of building a large, long wavelength synthesis array telescope for radio astronomical and ionospheric observations was met.

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Brian C. Hicks, Nagini Paravastu-Dalal, Kenneth P. Stewart, William C. Erickson, Paul S. Ray, Namir E. Kassim, Steve Burns, Tracy Clarke, Henrique Schmitt, Joe Craig, Jake Hartman, Kurt W. Weiler. 2012-10-01. A wide-band, active antenna system for long wavelength radio astronomy. https://doi.org/10.1086/668121

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