Optimal zero-crossing group selection method of the absolute gravimeter based on improved auto-regressive moving average model  

作　　者：牟宗磊 韩笑 胡若 Zonglei Mou;Xiao Han;Ruo Hu(College of Electrical Engineering and Automation,Shandong University of Science and Technology,Qingdao 266590,China;National Institute of Metrology China,Beijing 100029,China)

机构地区：[1]College of Electrical Engineering and Automation,Shandong University of Science and Technology,Qingdao 266590,China [2]National Institute of Metrology China,Beijing 100029,China

出　　处：《Chinese Physics B》2023年第11期347-354,共8页中国物理B(英文版)

基　　金：Project supported by the National Key R&D Program of China (Grant No. 2022YFF0607504)。

摘　　要：An absolute gravimeter is a precision instrument for measuring gravitational acceleration, which plays an important role in earthquake monitoring, crustal deformation, national defense construction, etc. The frequency of laser interference fringes of an absolute gravimeter gradually increases with the fall time. Data are sparse in the early stage and dense in the late stage. The fitting accuracy of gravitational acceleration will be affected by least-squares fitting according to the fixed number of zero-crossing groups. In response to this problem, a method based on Fourier series fitting is proposed in this paper to calculate the zero-crossing point. The whole falling process is divided into five frequency bands using the Hilbert transformation. The multiplicative auto-regressive moving average model is then trained according to the number of optimal zero-crossing groups obtained by the honey badger algorithm. Through this model, the number of optimal zero-crossing groups determined in each segment is predicted by the least-squares fitting. The mean value of gravitational acceleration in each segment is then obtained. The method can improve the accuracy of gravitational measurement by more than 25% compared to the fixed zero-crossing groups method. It provides a new way to improve the measuring accuracy of an absolute gravimeter.

关 键 词：absolute gravimeter laser interference fringe Fourier series fitting honey badger algorithm mul-tiplicative auto-regressive moving average(MARMA)model 

分 类 号：O314[理学—一般力学与力学基础]