低低跟踪重力卫星高精度微波测距系统数据预处理与分析

Data preprocessing and analysis of high-precision microwave ranging system for low-low satellite-to-satellite tracking mission

本文研究低低跟踪重力卫星任务核心微波测距系统的数据预处理与分析方法,实现关键载波频率不稳定性噪声的高效抑制,以及相关干扰、偏差的消除和矫正.依据理论分析成果,研发了相关处理与分析程序.本研究所完成的双频双向单程测距数据产品与GRACE Follow-On官方产品的残差远小于载荷设计精度指标,满足重力场反演的精度需求.针对最终数据产品中电子学噪声、系统噪声等噪声,讨论评估与分析方法.本文通过引入电离层自由电子含量的空间非均匀性的频域分析方法,利用星间微波测距数据,实现针对自由电子含量的不同空间尺度变化行为及其全球分布特征的分析能力,从新视角为电离层的深入研究提供数据支撑.本研究可为我国低低跟踪重力卫星任务微波测距系统的数据预处理与分析提供相关技术积累和参考.

This paper studies the data preprocessing and analysis methods of the key microwave ranging system for the low-low satellite-to-satellite tracking gravity mission,and achieve the efficient suppression of the key carrier frequency noise,as well as the elimination and correction of the related interference and deviation.According to the theoretical analysis results,relevant processing and analysis procedures are developed.The residual between the dual one-way ranging data product completed by this research and the official product of GRACE Follow-On is much smaller than the design requirement of the payload,which meets the accuracy requirements of gravity field inversion.Evaluation and analysis methods for electronic noise,system noise and other noise in the final data product are discussed.In this paper,by introducing the frequency-domain analysis method of the spatial inhomogeneity of the ionospheric free electron content,and using the inter-satellite microwave ranging data,the ability to analyse the variation behaviour of free electron content at different spatial scales and its global distribution characteristics is realized,providing data support for the in-depth study of the ionosphere.This research can provide relevant technical accumulation and reference for the data preprocessing and analysis of the microwave ranging system for low-low satellite-to-satellite tracking missions of China.