中文摘要：

利用Galileo系统的轨道参数模拟了Galileo系统的卫星位置，并计算出DOP值，比较了同一地点同时段内GPS和Galileo的能见卫星个数及DOP值。与单个系统相比，GPS／Galileo组合在任意地点、任意时刻的观测卫星个数增加．其DOP值明显变小；同时计算了组合系统在不同卫星高度角情况下的DOP值变化，发现在卫星高度角较高时仍可以接收到四颗以上的卫星．其DOP值也能达到导航定位的要求。

英文摘要：

This paper uses the Galileo orbit parameter for simulating the Galileo satellite position and DOP, compares the visible satellite number and DOP between GPS and Galileo system,at same time and same place. The result indicates that Galileo constellation is better than GPS. And simulates GPS and Galileo combined constellation, more visible satellite brings diminished DOP, in contrast with single system, so that improves the position precision, and also broaden the scope of position due to limited elevation.