伪码测距系统，一种非常常见的测距系统，测距精度非常高，有需要的同学可以-Pseudo-code ranging system, a very common ranging system, ranging accuracy is very high, students can see there is a need

卫星间测距，采用伪码测距与双频测距相结合的方式，使得定位精度哟很大提高-Inter-satellite ranging, distance measurement with dual-band pseudo-code combination of distance, making the positioning accuracy greatly improved yo