无线电工程

在卫星通信过程中,对具有相对运动的卫星,星间链路的多普勒频移是不能忽视的。分析了空间圆轨道卫星星间链路的距离以及距离变化率,并进行了公式推导。在此基础上提出了一种以链路距离变化率作为卫星相对运动速度来计算星间链路多普勒频移的新方法,并以铱星系统和某中轨卫星系统为例,分别对同层高度星间链路和异层高度星间链路的多普勒频移进行仿真,给出了仿真结果。分析与结果表明,该方法合理、有效。

Doppler Shift in satellite communication should not be ignored for the satellites with relative motion.In this paper,the range and range-rate of ISL for circular orbit satellites are analyzed,the formula is derived.Then a new method to calculate Doppler Shift in ISL is presented,the range-rate is regarded as velocity of relative motion of satellites in this method.Then Doppler Shift in ISL of same altitude and ISL of different altitude is simulated,with an example of Iridium and MEO satellite system.It can be shown from the analysis and simulation result that this method is rational and effective.