【作者】 许海玉；

【导师】 林晓辉；

【作者基本信息】 哈尔滨工业大学 ， 飞行器设计， 2010， 硕士

【摘要】 传统的机械陀螺和激光陀螺捷联惯导系统具有体积大,重量大,可靠性低等缺点,而光纤陀螺捷联惯导系统正好弥补了上述不足,广泛的应用在了卫星导航系统上,而影响系统导航精度的主要因素之一是随时间积累而积累的光纤陀螺漂移。为了提高卫星姿态确定精度,本文对光纤陀螺噪声源进行了分析,并对光纤陀螺随机漂移数据进行了统计检验,这些统计检验包括平稳性检验、周期性检验、正态检验,并对数据进行预处理,采用时间序列分析法建立了自回归模型和自回归滑动平均模型,对光纤陀螺随机漂移进行了kalman滤波。此外,小波分析是一种具有多分辨分析能力的时频分析方法,适合对非平稳信号进行分析。小波分析也是用来分析光纤陀螺随机漂移的常用方法。本文研究了小波理论并对光纤陀螺随机漂移进行了小波分析。并用Allan方差法评定了两种滤波效果,Allan方差法评的结果表明,采用小波滤波省去了对光纤陀螺随机漂移数据的统计检验的工作,不用建立时间序列模型,仿真结果表明小波滤波能有效地减小光纤陀螺随机漂移,并且滤波效果优于kalman滤波。针对对地定向三轴稳定卫星,采用四元数法,基于扩展kalman滤波理论,设计了“光纤陀螺+星敏感器”模式的姿态确定系统,仿真结果表明光纤陀螺随机漂移的减小有利于卫星姿态估计精度的提高,进一步肯定了光纤陀螺随机漂移的滤波对提高系统精度的意义。更多还原

【Abstract】 Traditiona l mecha nical gyro SINS and laser gyro SINS have disad vantages suchas bulky, heavy, low reliability, and so on. FOG SINS can make up for thesedeficiencies, so it is used widely in satellite navigation system. One of the ma infactors affecting the accuracy of the system is that the drift of FOG increase s withtime.In order to improve the precision of satellite attitude determination, the paperanalyzes the noise source of FOG, and inspects the data of the random drift throughstatistica l test including stability test, period ic test and norma l test. After the datapretreatment, the regression model and the auto-regression moving model isestablished through the time series analysis theory. And then, the data of the FOGrandom drift is processed by Kalma n filter.In addition, wavelet analysis is a time-frequency analysis method with multiresolutionanalysis capability, which is suitable for non-sta tionary signa l analysis.Also, it is the usua l method to analyze the random drift of FOG. The paper studies thewavelet theory, by which analyzing the FOG random drift. Besides, the papercompares the results of the two filter methods with the Allan varia nce. The resultsshow that the wavelet filter method don’t need the statistica l test and the datapretreatment. Howev er, it can minish the FOG random drift effectively and the effectis better than Kalman filter method.The paper designs an attitude determination system of“FOG + Star sensor”using extended Kalman filter theory for the Earth-oriented three-axis stabilizedsatellite, basing on the quaternion method. The simulation results show the system isfeasible, with a high precision of attitude estimate. It also show minishing the FOGrandom drift can improve the precision of attitude estimate , proving the mea ning ofthe filter of FOG random drift to improve the system precision.更多还原