一种低轨卫星通信的定时提前计算方法

低轨(LEO)卫星网络作为地面网络的重要补充，是未来天地一体化网络的重要组成部分。由于LEO卫星的高移动速度以及星地通信的大传播距离造成了高传播时延，因此需要新的针对LEO卫星星地通信背景的上行链路的定时提前量(TA)的计算策略。本文基于LEO卫星的星地通信场景，介绍了TA及其在协议中的规定，并针对LEO卫星的特点，提出一种LEO卫星通信的定时提前计算方法。通过仿真分析验证了所提方案的有效性，为LEO卫星星地通信系统的设计提供了参考。

A timing advance calculation method for Low Earth Orbit satellite communication

As an important supplement to the terrestrial network, the Low Earth Orbit(LEO) satellite network is an important part of the future earth-earth integrated network. However, due to the high moving speed of LEO satellites and the long propagation distance of satellite-ground communication, large propagation delay is caused, therefore a new calculation strategy for the Timing Advance(TA) of the uplink in the satellite-ground communication background of LEO satellites is needed. Based on the satellite-earth communication scenario of LEO satellite, TA and its provisions in the protocol are introduced firstly. Then, according to the characteristics of LEO satellite, a timing advance calculation method of LEO satellite communication is proposed. The effectiveness of the proposed scheme is verified by simulation analysis, which provides a reference for the design of satellite-earth communication system of LEO satellite.