Abstract:The convergence speed and the precision of integrated multi satellite systems have a great relationship with the number and the space configuration of visible satellites and efficiency of system algorithm. The traditional selection algorithm cannot rapidly obtain the ideal spatial configuration, so, in this paper, the influence factors of the positioning accuracy calculation model and the GDOP value of integrated multi systems are discussed. An algorithm of convex hull with Graham’s scan is analyzed and then a fast satellite selection algorithm based on convex hull with Graham’s scan for multi satellite systems is achieved by programming. Meanwhile, simulation experiments are carried out on the selection effect and positioning efficiency of the proposed algorithm. Experimental results show that the number of selected satellites in this algorithm can be stabilized at 8 to 10, the constellation GDOP is obviously optimized and the spatial configuration is obviously improved.The optimization rate of convergence time reaches 40%, 20% and 7% corresponding respectively to X, Y, H with the traditional algorithm, and the positioning accuracy is higher. These results hold important significance in quick repair of ambiguity and improving positioning efficiency.
YANG Song,ZHANG Xianyun,DU Ning et al. A Fast Satellite Selection Algorithm for Multi-GNSS PPP Based on Convex Hull with Graham's Scan[J]. jgg, 2018, 38(2): 181-186.