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You are here: Allan's TIME > Publications > Allan Variance > Use in Radio-Astronomical Instrumentation

Allan Variance Use in Radio-astronomical Instrumentation

by Dr. Rudolf Schieder
26 March 2001

Professor, University of Cologne
Physikalisches Institut, Universität zu Köln

Telephone: 01149-221/470-3568
FAX: 01149-221/470-5162


Dear colleague,

I have just discovered your web-page, and I would like to make you aware of our introduction of Allan variance measurements several years ago, which is now in use by many groups dealing with radio-astronomical instrumentation. We have published our ideas about the use of Allan variance plots many years ago, and for this you might have a look on the following papers:

Characterization and Measurement of Radiometer Stability; G.Rau, R.Schieder, B.Vohwinkel; Proc. 14th European Microwave Conf., Sept. 10-13, 1984, Liege, Belgium, 248-253
Characterization and Measurement of System Stability; R.Schieder, G.Rau, B.Vohwinkel; Proc. of a SPIE conference on "Instrumentation for Submillimeter Spectroscopy", Dec. 5-6, 1985, Cannes, France
The Cologne Acousto-Optical Spectrometers; V.Tolls, R.Schieder, G.Winnewisser; Experimental Astronomy 1, 101 (1989)

The last paper demonstrates the importance of the method for the successful development of acousto-optical spectrometers (AOS) in general.

I would also like to bring to your attention that the Allan variance method has also played an important role for the development of the first space-borne AOS on board of NASAs Submillimeter Wave Astronomy Satellite (SWAS), which is successfully operating since more than two years by now. For this see e.g.

The SWAS Acousto-Optical Spectrometer; M.Klumb, J.Frerick, V.Tolls, R.Schieder, G.Winnewisser; SPIE 2268, 305 (1993)
Acousto-Optical Spectrometers in Space; R.Schieder, J.Horn, O.Siebertz, M.Klumb, J.Frerick, V.Tolls; The 30th ESLAB Symposium on Submillimetre and Far-Infrared Space Instrumentation, ESTEC, Noordwijk, The Netherlands, Sept. 24-26, 1996, ESA SP-388, 187
SWAS-AOS: The First Acousto-Optical Spectrometer in Space; J.Frerick, M.Klumb, R.Schieder, V.Tolls, G.Winnewisser, Proc. "Infrared Spaceborne Remote Sensing VII", M.Strojnik, B.F.Andresen Eds., SPIE 3759, 170-179 (1999)

We are presently working on a new generation of AOSs for the ESA cornerstone mission HERSCHEL (former FIRST), for which the Allan variance method also plays an important role. See also:

Wide-Band Spectrometer for HIFI-FIRST; R.Schieder, O.Siebertz, F.Schloeder, C.Gal, J.Stutzki, P.Hartogh, V.Natale, Proc. of "UV, Optical, and IR Space Telescopes and Instruments", J.B.Breckinridge, P.Jakobsen Eds., SPIE 4013, 313-324, (2000)

A similar development is going on for the air-borne observatory SOFIA in Cologne. In all these papers the Allan variance are very important tools for the development. Recently we have submitted a paper dealing exclusively with consequences of Allan variance measurements for the observing strategy using radio-astronomical observatories. The paper has recently been submitted, and, in case you are interested, we can send you a copy.

With my best regards,

Rudolf Schieder

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