一种卫星钟差异常精确探测的两步法策略

针对卫星钟差数据中的粗差和钟跳两类异常进行精确探测，提出使用历元单差算法和拟准检定法相结合的两步法策略，第1步，依据钟跳和粗差在历元单差序列中不同表现特点，采用历元单差法探测疑似钟跳点并剔除部分粗差；第2步，对按疑似钟跳分段的数据使用拟准检定法精确探测粗差。通过模拟数据算例阐述钟差异常探测过程并进行性能分析，通过实测数据进行算法有效性验证，结果表明，仅使用历元单差法能有效探测疑似钟跳点和部分粗差，其探测的疑似钟跳点包含了真实钟跳；使用两步法既能有效规避钟跳影响，又能精确探测小粗差，探测能力接近底噪的2倍中误差。

A Two-step Method for Precise Detection of Satellite Clock's Abnormal Data

To detect clock jump and gross error in data of satellite clock, a two-step method for error detection of satellite clock data is proposed by combining the single difference algorithm of epochs and quasi-accurate cetection method (QUAD). In the first step, a single difference algorithm of epochs is used to detect suspected clock jump and eliminate the gross error points according to the different performance characteristic of clock jump and gross error in the sequence of single difference of epochs; and in the second step, QUAD is used to detect gross error precisely for the data by segment according to the suspected clock jump. The detecting process is set forth and the performance is analyzed by using simulating data, and the algorithm is verified by practical data, both examples show that using only single difference algorithm of epochs can effectively detect suspected clock jump points and partial error, while using the two-step method can effectively avoid clock jump influence, and can accurately detect small gross errors, which is close to two times the background noise's standard deviation.