H. Hase
Phase Centre Determinations at GPS-Satellites with VLBI
 
                   ABSTRACT
 
 
The collocation of various geodetic space techniques provides the tie of satelli
te reference systems into the quasi-inertial reference system of radio sources.
The concept of a fundamental station is the ideal realization for collocating
instruments on Earth's surface. A challenge is to tie satellite transmitters of
navigation systems directly into the International Celestial Reference Frame,
the most accurate realization of a quasi-inertial reference system with VLBI
measurements. An orbit determination of the phase centre of the satellite
transmitters complement existing orbit determinations. For VLBI-type
determinations some research and development work needs to done. For this
purpose a new type of dual beam radio telescopes will be of advantage. If the
method will be successful an inertial frame service is possible in the future.
 
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In Proceedings of the 13th Working Meeting on European VLBI for Geodesy
and Astrometry, Viechtach, 1999
 
Keywords: GPS transmitter, phasecenter, phase referencing, dual beam radiotelescope