e-VLBI Progress of the Chinese VLBI Network

摘要

At present the Chinese VLBI Network (CVN) contains two fixed stations, one mobile station and the 2-station Shanghai correlator. The PC-based VLBI data acquisition terminal and playback unit named CVN harddisk system was developed at Shanghai Astronomical Observatory recently. The CVN harddisk systems were installed at Sheshan station, Urumuqi station and Shanghai Observatory, and several e-VLBI test observations were completed in 2003. Now the Shanghai correlator is able to correlate the data from the tape or the harddisk. Based on the CVN harddisk system, research on the software correlator was also carried out. The prototype software correlator was successfully used in the station fringe check, satellite fringe search and data processing. When processing the satellite observation data, the hardware Shanghai correlator can produce the group delay & delay rate, guided by the software correlator. The CVN will be updated to a realtime VLBI network, including 4 stations and 2 realtime 5-station correlators (hardware & software), which will be applied to the Chinese Lunar satellite navigation, as well as the geodetic and astronomical observations in the future. Researches on the digital BBC and formatter have been carried out.