Munich, May, 6th, 1998
Dear Dr. Kondo,
Last week an important national conference on Earth rotation and reference Systems took place in Wettzell. One of the most exciting topics was the real-time VLBI. In my talk, I refered to the Japanese Key Stone project as the world-wide first successful realiziation of broad-band VLBI in real-time. Real-time VLBI was also a main topic in a symposium on 'Instrumental challenges in geodesy' at the XXXIIIrd General Assembly of the European Geophysical Society in Nice. It's very important for German and European activities to have such an excellent example which the IERS VLBI Technical Development Center developed. We'd like to observe the Earth rotation parameters by VLBI in near real-time because they are needed for precise positioning and navigation (e.g. by GPS), for space tracking and also as references for other on-line observing techniques of the Earth rotation (e.g. laser gyros, supra-fluid helium gyros).
Let me inform you, please, that it is intended to develop the real-time capability of the Wettzell VLBI station in the near future. I hope that these developments could learn from your experiences and real-time VLBI experiments between Wettzell and Japan will be possible, soon.
Working on geodetic VLBI for almost 20 years let me also express my thanks for sending me the TDC News which is an extremely interesting publication useful for my whole group. I read all the articles carefully. In particular we are interested on all reports dealing with the broadband communication between the radiotelescopes and the central processor and those dealing with automation of the data analysis. Also papers on more general aspects, e.g. reference frames, Earth rotation are very useful for us.
As the impact of the Key Stone project on the international VLBI activities is considerably large I would be very pleased to see these efforts continuing or even growing and I send you and all the TDC members our best wishes for the future.
Yours sincerely
Harald Schuh
(Head of Earth rotation section at DGFI (German Geodetic Research
Institute), responsible for the VLBI group at DGFI)