公开(公告)号：US10270633B2

公开(公告)日：2019-04-23

申请号：US15526586

申请日：2015-11-13

Applicant: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY

Inventor： Wataru Kokuyama

IPC: G01B9/02 ,  G01J3/02 ,  G01J3/45 ,  G01S7/40 ,  H03D3/02 ,  H03K5/26 ,  G01J3/453 ,  G01R27/28 ,  G01S13/34 ,  G06F17/14 ,  H03L7/085 ,  H04L27/233

Abstract: The inventive phase measuring device includes a first A/D converter 2 that digitizes a first periodical input signal X at each predetermined sampling timing and outputs the resultant signal as a digital signal Xd, a first zero-crossing identification means operable to detect a sign of Xd, a counting processing unit 4 that counts a difference in the number of times of zero-crossing detection by the first zero-crossing identification means and calculates the difference at each sampling timing, and a fraction processing unit 5 that computes a fraction of the number of times of zero-crossing detection on the basis of Xd at sampling timings immediately before and immediately after determination of zero-crossing by the first zero-crossing identification means. An averaging processing unit 6 performs averaging by adding up and totalizing the outputs from the counting processing unit 4 and the fraction processing unit 5, thereby computing a phase. The inventive device thus implements a digital phase measuring device and a digital phase difference measuring device that allow input of periodical signals in a wide frequency range and that are capable of accurate and real-time measurement.