Galileo卫星星钟故障前后信号质量分析  

Analysis of Signal Quality of Galileo Satellites Before and After Atomic Clock Failures

作　　者：熊定喜 郭树人[1] 康立[2] XIONG Dingxi;GUO Shuren;KANG Li(Beijing Institute of Tracking and Telecommunications Technology,Beijing 100094;National Time Service Center,Chinese Academy of Sciences,Xi’an 710600)

机构地区：[1]北京跟踪与通信技术研究所,北京100094 [2]中国科学院国家授时中心,西安710600

出　　处：《飞行器测控学报》2017年第6期432-441,共10页Journal of Spacecraft TT&C Technology

摘　　要：星载原子钟是卫星导航系统的核心器件,是影响导航信号质量的重要因素。2016年11月,Galilco系统利用一箭四星发射升空4颗新一代Galilco卫星。根据观测显示,截至2017年7月,仅能接收到其中1颗卫星发射的导航信号。在2017年1月,欧洲航天局通告称多颗卫星原子钟大规模故障。针对此,40 m大口径高增益天线系统设备对不同批次和星钟故障情况的3颗Galilco卫星E5频点信号进行了数据采集处理,对各信号分量的功率谱、星座图、码片波形、相关损失、相关峰、S曲线偏差等信号质量指标进行了分析评估。结果表明,此次星载原子钟的大面积故障并未影响Galilco卫星信号的可用性,足够的星载备份钟避免了信号质量的严重恶化。Four additional Galilco satellites were launched in November 2016.Observations found that only one of the satellites transmitted navigation signal as of July 2017.In January 2017,the European Space Agency announced that nine atomic clocks stopped operation.Atomic clock,an important factor affecting the quality of navigation signals,is the core of a satellite navigation system.In this paper,the signal data on frequency E5 of three Galileo satellites was collected and processed by a 40 m diameter high gain antenna system.Parameters such as power spectrum,constellation,chip waveform,correlation loss,correlation peak and S-curve deviation were analyzed and evaluated.The results show that the fault of the atomic clocks did not affect availability of Galilco satellite signals.Adequate backup clocks on the satellites shall have avoided serious deterioration of signal quality.

关 键 词：卫星导航 Galilco系统 信号质量 星钟故障 

分 类 号：V474.25[航空宇航科学与技术—飞行器设计] P228.4[天文地球—大地测量学与测量工程]