【作者】 王雪峰；

【导师】 张世杰；

【作者基本信息】 哈尔滨工业大学 ， 航天工程， 2015， 硕士

【摘要】 随着遥感技术的飞速发展与需求种类的不断丰富,遥感任务对于分辨率的要求越来越高。卫星作为有效载荷的平台,在发射与在轨工作的过程中,会受到各种因素的影响,从而产生指向误差。指向误差的存在,是制约高分辨率成像的关键因素,因此本文以高分辨率遥感成像为背景,对指向误差的定义、度量指标以及指向误差综合与分配预算构建方法展开了研究与分析,本论文的主要研究内容如下:指向误差由指向精度误差与指向稳定度误差组成,指向稳定度误差由条带误差与颤振残差组成。低频指向误差主要造成指向精度误差,高频指向误差主要造成指向稳定度误差。提出了指向误差的时域与频域度量形式,同时给出了指向误差的不同的统计解释方法与度量指标。在此基础之上,建立了指向误差的状态空间模型。在计算过程中,状态空间模型可以避免复杂的数值积分,利用解析的表达形式对指向误差进行计算。以点扩散函数为基准,分析了指向误差对成像质量的影响,指出了指向误差的存在,可以使点扩散函数变宽,从而造成成像质量的下降。对能够造成指向误差的误差源进行了描述与建模。在卫星发射至在轨开展工作的过程中,对卫星平台及有效载荷能够产生干扰的误差源大致可以分为四类:安装误差、敏感器误差、执行机构误差与空间环境干扰。利用概率密度函数对指向误差源进行了数学描述,得出了指向误差源的统计性质;分析了指向误差的传递过程,建立遥感卫星系统中所需的传递模型;提出了不同类型的指向误差的合成方法,分析了存在相关性的指向误差源与不存在相关性的指向误差源的综合方法。对指向误差的分配预算构建进行了研究与分析。分析了指向误差分配预算的构建步骤与流程;依据指向误差的变化性质,对指向误差进行了划分,将指向误差分为偏差、均匀分布误差、高斯误差、正弦误差以及漂移误差,对不同误差的度量指标、统计解释方法进行了分析;通过具体实例分析,说明了指向误差分配预算的构建过程,从而得出指向误差分配预算在遥感卫星初步设计过程中具有较为重要的意义。更多还原

【Abstract】 With the rapid development of remote sensing technology and the enrichment of types of requirements, there is the increasingly high demand on resolution for remote sensing mission. As the platform of payloads, satellites will be affected by various factors during launch and on-orbit work and service, resulting in pointing errors. Due to the existence of pointing errors, the resolution may be affected, so it is the key factor of high resolution imaging. This paper focuses on the high-resolution remote sensing mission, and carries out a comprehensive research about the definition of point errors, pointing error metrics and pointing error budget, and the main research contents are as follows:Pointing errors are made of the pointing accuracy errors and the pointing stability errors, and the pointing stability errors are made of errors which can lead the smear errors and jitter errors. Low-frequency pointing errors cause mainly the pointing accuracy errors, high-frequency pointing errors causes mainly the pointing stability errors. The time domain and frequency domain metrics for pointing errors is proposed, and the methods of different statistical interpretations for pointing errors and pointing error indices are established. On the basis of this, the pointing errors are modeled by using the state space method. State space model can calculate the pointing error in the analytic form, so it can avoid complex numerical calculations. Referred to point spread function, the effect of pointing errors on the imaging quality is analyzed. Pointing error can widen the point spread function, so it may influence the image quality.The sources which can cause pointing errors are characterized and modeled. During the launch and on-orbit work and service, remote sensing satellite platforms and payloads may be influenced by a lot of error sources, including misalignment, sensors noises, actuator errors and environment disturbance. Pointing error sources are characterized by usage of the probability density functions, and the statistical properties are obtained. The process of the errors transformation is analyzed and modeled. The error contribution methods are proposed, including the pointing errors which are correlated and uncorrelated.The establishment of pointing error budget is analyzed and studied. The steps and process belong to error budget are proposed. Based on the properties of the pointing errors, we can divide the errors into bias, drift error, uniform error, period error, sinusoidal error and random error. By using one example, the error budget is illustrated, and based on the results, we can conclude that in the preliminary design phase or the whole lifetime of the remote sensing project, the pointing error budget plays an important role on it and the research on that is significantly meaningful.更多还原