Abstract: With the increase in the number of navigation satellites and the development of chip technology,the number of observable satellites from GNSS terminals has greatly increased,greatly improving the satellite geometry. However,if all observation satellites are required to perform high-precision positioning calculations,the computing resources and power consumption required by the terminal will increase rapidly. To address this problem,this paper proposes a fast satellite selection method based on (weighted geometric dilution precision,WGDOP). When the number of satellites that can be solved is limited,a satellite combination with optimal geometric structure and signal quality can be obtained quickly. Experimental results show that compared with the traditional satellite selection method based on (geometric dilution precision,GDOP),when the number of satellites that can be solved is less than 15,the method proposed in this paper improves the accuracy and fixation rate by 10 times and 40% respectively. Then a real-time RTK test is conducted based on the AG3335 chip. Using the method in this article to select 20 satellites for calculation can greatly reduce the time-consuming of positioning calculation while maintaining high positioning accuracy.

Key words: low-cost chips, weighted geometric dilution precision, lightweight fast satellite selection algorithm, chip application testing