Study on the improvement of measurement accuracy in GPS

GPS (Global Positioning System) is 3D positioning system using the signal of satellites, and it is used in various situations. The arrangement and the number of GPS satellites influence measurement accuracy. DOP (Dilution of Precision) is an index evaluating the arrangement of satellites. We propose a new index that evaluates influence of each satellite on the arrangement of satellites. We relate the index to a weight coefficient of each satellite and perform measurement simulations to improve measurement accuracy in DGPS