北斗导航卫星氢原子钟性能分析评估

星载原子钟是导航卫星最重要的载荷之一,负责星上时间基准的产生和维持.我国北斗三号导航试验卫星首次配置了23 kg级被动型星载氢原子钟,验证了氢原子钟的空间环境适应性和在轨性能,实现在轨运行误差小于1 ns/d.在北斗三号全球导航卫星系统中,氢原子钟已作为主钟应用至GEO,IGSO和MEO三类导航卫星,对系统的运行发挥至关重要的作用.本文从氢原子钟的机理和性能评估方法出发,比较了铷钟、铯钟和氢钟三类原子钟的性能差异,根据地面和在轨测试数据,给出氢原子钟在轨运行性能评估结果;最后利用卫星遥测数据建模,对氢原子钟健康状况和寿命进行了初步分析.

Performaces and telemetres analysis of BD satellite passive hydrogen maser

An atomic clock is one of the most important payloads in navigation satellites.It is in charge of generating and maintaining the satellite time.The performance and on-orbit adaptability of a 23-kg passive hydrogen maser(PHM)have been verified using the experimental satellite of the third-generation Beidou satellite navigation system(BDS-3).The clock offset of the PHM is less than 1 ns per day.In BDS-3,PHMs operate as the master clocks in the GEO,IGSO,and MEO satellites;therefore,they are important in the system operation.Herein,we present the design and performance evaluation of the PHM and compare the hydrogen maser,rubidium atomic clock,and cesium atomic clock.Using the satellite-ground time-difference data,we analyze the frequency stability and time prediction accuracy.Furthermore,we perform a preliminary analysis of the operating status and aging trend based on the satellite telemetry data.