ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-24-2419-2006 Phase calibration of the EISCAT Svalbard Radar interferometer using optical satellite signatures Sullivan J. M. 1 Ivchenko N. 2 Lockwood M. 3 Grydeland T. 4 Blixt E. M. 4 Lanchester B. S. 1 School of Physics and Astronomy, University of Southampton, Southampton, Hampshire, UK Alfvén Laboratory KTH, Stockholm, Sweden Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, UK Dept. of Physics and Technology, University of Tromsø, N-9037 Tromsø, Norway 20 09 2006 24 9 2419 2427 Copyright: © 2006 J. M. Sullivan et al. 2006 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/24/2419/2006/angeo-24-2419-2006.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/24/2419/2006/angeo-24-2419-2006.pdf

The link between natural ion-line enhancements in radar spectra and auroral activity has been the subject of recent studies but conclusions have been limited by the spatial and temporal resolution previously available. The next challenge is to use shorter sub-second integration times in combination with interferometric programmes to resolve spatial structure within the main radar beam, and so relate enhanced filaments to individual auroral rays. This paper presents initial studies of a technique, using optical and spectral satellite signatures, to calibrate the received phase of a signal with the position of the scattering source along the interferometric baseline of the EISCAT Svalbard Radar. It is shown that a consistent relationship can be found only if the satellite passage through the phase fringes is adjusted from the passage predicted by optical tracking. This required adjustment is interpreted as being due to the vector between the theoretical focusing points of the two antennae, i.e. the true radar baseline, differing from the baseline obtained by survey between the antenna foot points. A method to obtain a measurement of the true interferometric baseline using multiple satellite passes is outlined.

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