D. Behrend, A. Rius
Geodetic Control of the Madrid DSS65 VLBI Antenna
 
                   ABSTRACT
 
 
This presentation deals with the determination of the reference
point of the NASA Madrid Deep Space Communications Complex
(MDSCC), Spain, DSS65 VLBI antenna using geodetic means. Firstly,
four geodetic observation campaigns performed by the National
Geographical Institute (IGN) of Spain in the period 1988-1998
are evaluated. Results indicate that the antenna was stable in
horizontal position at the few millimeter level neglecting a
7 mm change in the north component which only showed up in one
of the campaigns. The height, on the other hand, appears to have
undergone a significant uplift of about 2 cm.
Secondly, monthly taken spirit levelling data of the azimuth
runner level (part of the MDSCC station monitoring programme)
are utilized to investigate the possibility of propagating
variations in the runner level to the reference point. Using
a simple rigid body model, unsatisfactory results have been
obtained as the error estimates exceed the displacement signal
and as the model displacements do not correlate with the IGN
results.
 
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In Proceedings of the 13th Working Meeting on European VLBI for Geodesy
and Astrometry, Viechtach, 1999
 
Keywords: DSS65, MDSCC, geodetic control, reference point