The Real-time VLBI Technology

With the development of communication technology the data network comes replacing the traditional tape recording and transmission. The real-time VLBI technology directly transmitt ing data to the processing center consists of two technical levels, quasi-real-t ime and true real-time. This is a leap in the development of VLBI technology. The real-time VLBI, besides the high accuracy, sensitivity and all weather and full-time passive observat ion in the traditional VLBI, has the characteristics of simple equipment, high automatic, real time and easy to obtain wide-band ability and high sensitivity with the help of modern communicat ion technology. The real-time VLBI is of importance to the scientific and application f ields of VLBI station detection, precise space vehicle tracking, intensive UT1 campaign, convent ional geodetic and astronomical observation.