中文摘要：

主要介绍了GPS星间链路（星间链路是卫星导航系统实现自主运行的一项重要的关键技术）的工作模式,重点讨论了GPS星间链路数据的模拟方法。采用契比雪夫多项式拟合方法,获得对IGS（International GPS Service）公布的GPS精密星历加密到以1 s为间隔的数据。由信号接收时刻获得的两颗卫星间的距离作为初始值,反复迭代推算出发射信号的卫星发射信号的时刻,从而得到两颗卫星间的星间伪距观测值,再加上各项约束条件（如噪声,钟差等）后获得了两颗卫星间模拟的星间链路数据。

英文摘要：

The inter-satellite link（ISL） is one of key techniques in the autonomous operation of satellite navigation system.This article mainly describes the mode of GPS ISL and focuses on the simulation method of the GPS ISL data.The data from GPS precise ephemeris published by IGS is densified to a time interval of 1 s,by using Chebyshev polynomial fitting method.First,the distance between two satellites at the time of signal receiving is set as the initial value.Then the moment of signal transmitting for the transmitting satellite is calculated iteratively.Therefore the pseudo-range observation between two satellites can be obtained.Coupled with the constraint conditions（e.g.noise,clock offsets）,the simulated inter-satellite link data are obtained finally.