不同采集设备时间对准研究及误差分析

Study on Time Calibrating of Different Collectors and Deviation Analysis

在数据采集和测试领域,经常出现对不同采集设备的记录参数进行对比分析的情况。为保证对比分析的正确性,需要对来自不同采集设备的数据进行时间上的对准。针对采集设备缺少时间信息的情况,提出一种利用关键参数的关键变化节点实现不同采集设备时间对准的方法。选取记录在不同采集设备中的同一个参数设为关键参数,分别查找该参数在两采集设备中发生同一状态变化的采集时刻位置,该时刻位置作为关键时间节点。利用该关键节点和采集设备的采集频率,实现不同采集设备起始时刻的对准。最后利用数值内插,实现不同采集设备在任意时刻的时间对准。通过均值和方差工具对该方法的时间对准精度进行分析,结果表明时间对准精度取决于采集设备的采集频率,当不同采集设备采集频率差异较大时对准精度取决于较低的采集频率。

Recorded param eters from different collectors need to be compared and analyzed frequently in data collecting and testing domain,and recorded data from different collectors must be calibrated in time in order to ensure the correctness of the data comparative analysis.For the condition of data collecting without time information,the way that time calibrating by key time switch node of key parameter is put forward.Firstly,a parameter that’s recorded in both collector is selected as the key one.Then,the acquisition time and position of the parameter with the same state change in the two acquisition equipment are respectively found,and the time and position are taken as the key time node.Start time of different colloctors could be calibrated based on key time node as well as sampling frequency of both colloctors.Finally,arbitary time position’s time calibration would be realized by value interpolation.Time calibrating precision is analyzed by tools of mean and variance,the result shows that time calibrating precision depends on colletors’sampling frequency.When sampling frequency of different collector has great divergency,calibrating precision depends on low sampling frequency.