近地卫星测控中的一种GPS时间同步方法

针对近地卫星测控中的星地时间同步问题，首先建立星地时差模型，在重点分析星地时差误差源的基础上，提出使用星载 GPS 接收机的时间信息对卫星时间进行同步，并建立 GPS 时间同步模型，从理论上对星地时差进行误差源的比较和分析，最后应用于近地卫星测控。结果表明，利用 GPS 的星地时间同步方法的误差源少，时间同步精度高，误差在±1ms 以内，精度优于 1ms，并施用于在轨卫星长期管理与测控。

GPS Time Synchronization for LEO Satellite in TTC

With respect to time synchronization of LEO (Low Earth Orbit) satellite platform in TTC (Tracking, Telemetry and Command), a traditional model has presented to calculate the time difference from satellite to the ground. By analyzing the error sources that are six in the traditional model, the traditional model has modified to be a new GPS (Global Positioning System) time synchronization model to calculate the time difference from satellite to GPS with telemetry information originated from the satellite. Validation in TTC has shown that the GPS (Global Positioning System) time synchronization model has an error source decreasing to two, and has a time error within 1ms and a time precision less than 1ms, and is applicable to long-term management for on-orbit satellite in TTC.