However, the system requires 18 satellites to cover Russia; and 24 dependable satellites operating round the clock are needed for accurate globalnavigation.
该系统需要18颗卫星才能覆盖俄罗斯全境，需要24颗卫星才能实现精确的全球导航。
2
GPS, or global positioning system, is a satellite-based navigation system made up of a network of 24 satellites.
或者说全球定位系统，是一种基于24颗卫星网络的卫星导航系统。
3
The third step, about 2020, built by more than 30 satellites, global coverage Compass global satellite navigationsystem, the system performance over the same period the international advanced level.