星载晶振短稳对导航增强系统PPP精度的影响分析  

Analysis of impact of crystal oscillator short stability on PPP accuracy of navigation enhancement system

作　　者：刁文婷 郑戈 王冬冬 DIAO Wenting;ZHENG Ge;WANG Dongdong(Beijing Research Institute of Telemetry,Beijing 100076,China)

机构地区：[1]北京遥测技术研究所,北京100076

出　　处：《遥测遥控》2023年第3期31-39,共9页Journal of Telemetry,Tracking and Command

基　　金：科技部地球观测与导航专项课题(2016YFB0500900)。

摘　　要：分析星载恒温晶振(Oven Controlled Crystal Oscillator,OCXO)短稳对导航增强系统精密单点定位(Precise Point Positioning,PPP)精度的影响。本文首先介绍了OCXO短期频率稳定度的概念,然后根据其短稳特性进行噪声反演,最后建立了基于OCXO短稳噪声反演的系统PPP定位模型,将短稳量级不同的OCXO反演噪声引入模型并对系统最终PPP定位精度进行分析比较。实验表明:在无控制段调校星上时频的情况下,选用短稳量级为E-13的OCXO在中长观测时间段内(<1000 s)可满足系统厘米级的定位需求。该分析可为低轨导航增强系统的时频指标设计提供一定参考。To analyze the effect of Oven Controlled Crystal Oscillator(OCXO)short-stability on the accuracy of Precise Point Positioning(PPP)of navigation enhancement system.Firstly,this paper introduces the concept of OCXO short-term frequency stability,and then inverts the noise according to its short-term stability characteristics.Then,the PPP positioning model of the system based on OCXO short-term stability noise inversion is established,and OCXO inversion noise with different short-term stability magnitude is introduced into the model,and the final PPP positioning accuracy of the system is analyzed and compared.The experimental results show that the OCXO with the short-stability order of E-13 can meet the centimeter-level positioning requirements of the system in the medium and long observation periods(<1000 s)without the control section to adjust the on-board time-frequency.The analysis can provide some reference for the time-frequency index design of LEO navigation enhancement system.

关 键 词：恒温晶振 短期频率稳定度 精密单点定位 

分 类 号：V474.25[航空宇航科学与技术—飞行器设计] TP752[自动化与计算机技术—检测技术与自动化装置]