北斗系统空间信号接口控制文件正式版。北斗系统基本服务性能如下：位置精度：平面 10米、高程10米；测速精度每秒0.2米；授时精度单向50纳秒；可提供双向高精度授时和短报文通信服务。通过广域差分和地基增强等手段，北斗系统服务 性能还可进一步提高，满足各类用户需求。-Official version of the the Beidou system space signal Interface Control Document. The Beidou system performance are as follows: position accuracy: plane 10 meters, 10 m elevation　velocity accuracy of 0.2 meters per second　timing accuracy of the one-way 50 nanoseconds　provide two-way high-precision timing and short message communication service. By means of wide area differential and ground-based augmentation Beidou system performance can be further improved to meet the needs of all types of users.