从古至今,人类发明了多种导航方法。天文导航是通过观测天体的位置来确定自身位置和方向的导航技术,所需设备简单,但受气象条件限制。无线电导航是利用无线电保障运载工具准确到达目的地的导航技术,虽不受气象条件影响,但无线电波的传播距离有限。其他导航方法也各有不足。目前,卫星导航是比较理想的导航技术,利用一组导航卫星,就可以克服诸多限制,定位、导航精度较 Since ancient times, humans invented a variety of navigation methods. Astronomical navigation is a navigation technique that determines its position and orientation by observing the position of the celestial body. The required equipment is simple, but limited by meteorological conditions. Radionavigation is a navigation technique that uses radios to ensure that vehicles reach their destination accurately. Although not subject to meteorological conditions, the spread of radio waves is limited. Other navigation methods are also inadequate. At present, satellite navigation is an ideal navigation technology. With a set of navigation satellites, many limitations, positioning and navigation accuracy can be overcome