This paper presents some e-VLBI progress of CVN (Chinese VLBI Network).Presently CVN consists of two fixed stations located in Shanghai Sheshan and Urumqi Nanshan, one mobile station in Yunnan Kunming, and one 2-station hardware correlator (Shanghai correlator) in Shanghai Astronomical Observatory (SHAO). In 2003, a PC-based VLBI data recording and playback unit named CVN harddisk system was developed at SHAO and several systems were installed in CVN. Several e-VLBI experiments have been performed with this system since 2003. Now the Shanghai correlator is able to process the data from harddisks or tapes. Based on the CVN harddisk system, a prototype software correlator was developed and used in the station fringe checkout, the fringe search of the satellite signal and data processing.The first domestic 3-station delay, delay rate closure test of the satellite VLBI observation and the first domestic satellite orbit determination test using VLBI were successfully accomplished based on the results of the software correlator. Besides, the software correlator acts as the fringe guider of the Shanghai correlator. To satisfy the requirements of the Chinese lunar exploration project, CVN will be upgraded to a realtime VLBI network, including 4 stations and two new realtime correlators (hardware and software). e-VLBI will be applied to the lunar satellite navigation, as well as other geodetic and astronomical observations in the future.%介绍了中国VLBI网(CVN)的e-VLBI技术研究进展.CVN包括上海余山、乌鲁木齐南山2个固定观测站和云南昆明的流动站,以及上海天文台的2台站硬件相关处理机.2003年上海天文台自行研制了基于PC技术的VLBI数据记录、回放系统,命名为CVN硬盘系统,并成功将其安置于CVN观测站和处理机系统.硬件处理机经过改造后,已能处理来自硬盘和原有磁带系统的数据.从2003年至今,中国VLBI网采用该硬盘系统进行了多次VLBI观测和e-VLBI试验.在CVN硬盘系统基础上,软件相关处理技术的研究也得以开展.软件相关处理原型程序已经被用于台站条纹检测、卫星条纹搜索和数据处理中.该软件获得的计算结果被成功用于国内第一个3台站卫星VLBI的延迟和延迟率闭合试验,以及国内首次利用VLBI数据进行的卫星定轨试验.除此之外,该软件还用作硬件处理机的条纹引导器.为适应未来"嫦娥"月球探测工程,CVN将扩展成含有4个观测站和2个相关处理机(硬件、软件)的实时VLBI网.今后,e-VLBI将被应用于月球卫星导航以及测地和天体物理的VLBI观测.
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