Title:
FREQUENCY MEASURING APPARATUS AND FREQUENCY MEASURING METHOD
Document Type and Number:
WIPO Patent Application WO/2007/119488
Kind Code:
A1
Abstract:
In a first frequency measuring apparatus, a frequency or a period can be measured with high accuracy and high resolution without increasing a sampling interval because of using times at many zero cross positions for the measurement by measuring the period or the frequency of waveform information on the basis of the average value of the time at each of the zero cross positions in a predetermined range including a zero cross position whose time is to be measured. In a second frequency measuring apparatus, the frequency or the period can be measured with high accuracy and high resolution without increasing the sampling interval because of using the times at many zero cross positions for the measurement by measuring the period or the frequency of the waveform information on the basis of the average value of the difference between a plurality of the times calculated from the time at each of the zero cross positions in a predetermined range including the zero cross position whose time is to be measured.
Inventors:
FUJII YUSAKU (JP)
Application Number:
PCT/JP2007/055885
Publication Date:
October 25, 2007
Filing Date:
March 22, 2007
Export Citation:
Assignee:
UNIV GUNMA NAT UNIV CORP (JP)
FUJII YUSAKU (JP)
FUJII YUSAKU (JP)
International Classes:
G01R23/10
Foreign References:
| JPH05340975A | 1993-12-24 | |||
| JPH09318682A | 1997-12-12 | |||
| JP2002162269A | 2002-06-07 |
Other References:
MINAMI S.: "Kagaku Keisoku no tame no Hakei Data Shori", vol. 6TH ED., 20 November 1988, CQ PUBLISHING CO., LTD., pages: 86 - 95, XP003018281
FUJII Y. AND VALERA J.D.R.: "Impact force measurement using an inertial mass and a digitizer", MEASUREMENT SCIENCE AND TECHNOLOGY UK, vol. 17, no. 4, 23 March 2006 (2006-03-23), pages 863 - 868, XP020103456
FUJII Y. AND VALERA J.D.R.: "Impact force measurement using an inertial mass and a digitizer", MEASUREMENT SCIENCE AND TECHNOLOGY UK, vol. 17, no. 4, 23 March 2006 (2006-03-23), pages 863 - 868, XP020103456
Attorney, Agent or Firm:
NAKAJIMA, Jun et al. (NAKAJIMA & KATO Seventh Floor, HK-Shinjuku Bldg., 3-17, Shinjuku 4-chome, Shinjuku-k, Tokyo 22, JP)
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