Open AccessDetermination of Propagation Times of Finite Ultrasonic Signals in the UFM Measuring Path
Author(s) -
С. И. Герасимов,
Vladimir Glushnev,
I. N. Zhelbakov
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2096/1/012189
Subject(s) - discretization , truncation error , signal (programming language) , correlation function (quantum field theory) , function (biology) , ultrasonic sensor , mathematics , algorithm , observational error , acoustics , ultrasonic flow meter , approximation error , sampling (signal processing) , path (computing) , discretization error , mathematical analysis , computer science , statistics , physics , detector , telecommunications , spectral density , evolutionary biology , biology , programming language
This article provides a brief analysis of the error in calculating the discrete crosscorrelation function of the transit-time ultrasonic flowmeter signals. Special attention is paid to the study of the influence of the obtained discrete correlation function inaccuracy on the ultrasonic flowmeter’s propagation times determining error. It is known that for real time-limited acoustic signals, the discrete correlation function values are calculated with a significant error. The consequence of this is the appearance of the measurement error of the time delay between signals. The reason for this phenomenon is incorrect truncation of finite length digital sequences of the received acoustic signals. The report presents and describes an improved cross-correlation method for determining the time difference. The new algorithm takes into account the existing discretizing parameters of the received UPS – sampling frequency, sequence size and the truncated signal’s shape. Theoretical analytical expressions for the signals discrete cross-correlation function estimating are obtained as an approximation of a continuous function (the method of trapezoids and Simpson is used as an integral replacement). The numerical simulation by MatLab explains the error formation essence in the signal times difference calculating.