On June 13, 2012 morning, Ou Jikun, the researcher of Institute of Geodesy and Geophysics Chinese Academy of Science, and State Key Laboratory of Geodesy and Geodynamics, for the invitation of CAS Key Laboratory of Positioning and Time-keeping in Precision Navigation, made the academic exchange in NTSC, and gives a speech on “GNSS Data Processing Theory Extension and Selecting Weight Fitting Method” in the meeting room of the NTSC. Yang Xuhai, the researcher, hosted the meeting, research specialist stuff and graduated students, et al, from the Key Laboratory and the relevant fields participated in this symposium.