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A wideband lag correlator for heterodyne spectroscopy of broad astronomical and atmospheric spectral lines

Harris, A. I. and Zmuidzinas, J. (2001) A wideband lag correlator for heterodyne spectroscopy of broad astronomical and atmospheric spectral lines. Review of Scientific Instruments, 72 (2). pp. 1531-1538. ISSN 0034-6748.

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WASP2 is a lag correlation spectrometer that is optimized for astronomical heterodyne observations of spectral lines from mid-infrared through centimeter wavelengths. Since the instrument is a wideband microwave spectrum analyzer, its basic technology is well suited to radio astronomy, atmospheric remote sensing, and any other application which requires observations of broad spectral lines. In this specific instrument, eight 16 lag correlator boards form a 128 lag spectrometer with 33 MHz spectral resolution. The spectrometer's present microwave components dominate its gain shape, yielding a spectrometer which covers a useful (6 dB bandwidth) single band of 3600 MHz, from 280 to 3880 MHz. The correlator boards have a 3 dB bandwidth of 4000 MHz, from below 100 MHz to near their aliasing limit of 4200 MHz. WASP2 obtains its wide bandwidth with fully analog high frequency components: the voltage multipliers are transistor circuits and the delays are lengths of microstrip transmission line. WASP2 is simple, compact, requires little power, and integrates stably for many hours.

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Harris, A. I.0000-0001-6159-9174
Additional Information:©2001 American Institute of Physics. (Received 1 August 2000; accepted 26 October 2000) P. Teuben, K.G. Isaak, and J. Morgan have made essential contributions to the work described here. J. Ward, R. Baum, J. Staguhn, C. Holler, and J. Gottshalk have also made valuable contributions to spectrometer developments and use at the telescope. The authors thank T.G. Phillips and the staff of the Caltech Submillimeter Observatory for their support of this project. The staff of Protocircuits of Florida and Taconic ADD have been generous with advice and samples of board material. Financial support for parts of this work has been provided by NASA Grant No. NAG5-6044, NSF Grant No. AST-9819747, USRA funds for SOFIA heterodyne spectroscopy, and by the University of Maryland.
Subject Keywords:microwave spectrometers; millimetre wave spectroscopy; microwave spectroscopy; radioastronomical techniques; radiotelescopes; heterodyne detection; spectroscopy computing; spectral analysers; correlators; atmospheric measuring apparatus; analogue multipliers; signal processing equipment; astronomy computing; geophysical signal processing
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9096
Deposited By: Archive Administrator
Deposited On:26 Oct 2007
Last Modified:09 Mar 2020 13:18

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