Abstract:Based on GNSS data from the crustal movement observation network of China (CMONOC), we extract ionospheric delay from levelled carrier-phase observations, deduct the satellite hardware delay, then attach stochastic models of VTEC and DCB; these apply the semi-variable function as the spatial constraint of VTEC and the experienced VTEC and receiver hardware delay as the periods constraint, thus setting up the regional ionospheric grid model in real time. The results show that the inner precision of the model is about 0.3 m and the residuals are within 1 m. Taking GIM, which is the IGS ionospheric delay product, as reference, the characteristics of sequence diagram of VTEC are in accordance with GIM for a week. Furthermore, receiver hardware delay, with variations within 1.5 ns each day, are relatively stable. Compared with the regional station receiver hardware delay isolated from the original observation by using satellite hardware delay and spherical harmonic coefficient of IGS, the mean differences for a week are all within 2 ns.
WANG Qian,ZHANG Hongping,HUANG Ling et al. Real-Time Grid Algorithm Study of Ground-Based GNSS Regional Ionospheric Delay[J]. jgg, 2016, 36(12): 1069-1073.