High-precise data processing and analysis of GPS ultra-short baseline and basenet

With the improvement of the application of surveying and mapping products such as GNSS receivers and electronic total stations, modern geographic information industry is continually growing and developing. As one of the important standards for surveying and mapping instrument calibration, the baseline and basenet has provided important basic support for the development of various aspects of society for a long time. This paper uses GAMIT／GLOBK software to process the newly established ultrashort baseline basenet in high-precision, including baseline processing and network adjustment. The surrounding IGS stations and the Crustal Movement Network of China (CMONOC) reference stations are comprehensively used, and three methods are used to process the data separately. Then different aspects including  the normalized root mean square (NRMS) value, baseline repeatability and coordinate robustness after GPS network adjustment, we compared and analyzed the difference of these three methods. Results show that this ultra-short baseline basenet meets the specifications and design requirements. For similar GPS data processing from smallscale station networks, the hierarchical twostep method can be used to obtain a higher solution accuracy. This paper provides some useful experience for the calculation and analysis of high-precision GPS data from ultra-short baseline and basenet or similar regional station networks.