基于动态总方差的随机信号动态特性分析  

Dynamic Characteristic Analysis of Random Signal Based on Dynamic Total Variance

作　　者：张焕国[1] 吕莎[1] 

机构地区：[1]宜宾职业技术学院,宜宾市西郊新村74号644003

出　　处：《大地测量与地球动力学》2017年第1期86-88,110,共4页Journal of Geodesy and Geodynamics

基　　金：国家自然科学基金(61503390);四川省教育厅科研项目(16ZB0549)~~

摘　　要：动态Allan方差法是分析输出信号随机误差的一种新方法,但是窗函数截取数据会使数据减少、自由度降低,从而导致Allan方差估计值置信度低、误差变大等。本文设计了一种可以跟踪信号变化和减小估计值误差的动态总方差法,首先以确定的步长用固定的窗函数对原始信号进行截取,然后将窗函数内的数据用倒镜像映射进行延拓来提高置信度,最后将拓展后数据的方差值再用二维或三维图表达出来。仿真数据表明,动态总方差法既能及时地跟踪信号的动态变化,也可以克服估计值置信度低、误差大的问题。The dynamic Allan variance （DAVAR） is a new method to analyze the random error of output signals. However, it has defects such as poor confidence on the estimate and great estimation error, due to the reduced amount and freedom of data captured by the window. To solve this problem, a dynamic total variance approach is proposed to track variations in the signal and reduce estimate error. Firstly, we truncate the original signal with a fixed window by fixed step. Then, the data in the windows is extended by an inverted mirror mapping method to improve the confidence level. Finally, the Allan variance values of the extended data are calculated and expressed by two or three-dimensional figures. Simulation data shows that the dynamic total variance approach can track the dynamic variety of signals quickly, and also overcomes the problem of low confidence level and high estimate error.

关 键 词：动态总方差法 随机信号 动态特性 动态Allan方差法 

分 类 号：P207[天文地球—测绘科学与技术]