JPS5735764A - Fundamental frequency measuring device - Google Patents

Fundamental frequency measuring device

Info

Publication number
JPS5735764A
JPS5735764A JP11070680A JP11070680A JPS5735764A JP S5735764 A JPS5735764 A JP S5735764A JP 11070680 A JP11070680 A JP 11070680A JP 11070680 A JP11070680 A JP 11070680A JP S5735764 A JPS5735764 A JP S5735764A
Authority
JP
Japan
Prior art keywords
adds
arithmetic device
fourier coefficient
fourier
fundamental frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP11070680A
Other languages
Japanese (ja)
Inventor
Sumitoshi Mizoguchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
IHI Corp
Original Assignee
IHI Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by IHI Corp filed Critical IHI Corp
Priority to JP11070680A priority Critical patent/JPS5735764A/en
Publication of JPS5735764A publication Critical patent/JPS5735764A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R23/00Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
    • G01R23/02Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Frequencies, Analyzing Spectra (AREA)

Abstract

PURPOSE:To measure fundamental frequency at high accuracy even when a signal to be measured containes noise of high order by high speed Fourier transforming the input signal and finding out frequency that makes ampliture maximum by this Fourier coefficient. CONSTITUTION:An A/D converter 10 converts a signal to be measured inputted in a measuring time T into a digital signal and adds to a storage device 11, and a high speed Fourier transformer 12 calculates the Fourier coefficient and adds to a storage device 13. An arithmetic device 14 calculates the sum of square of the Fourier coefficient and adds to a storage device 15. A comparison arithmetic device 16 detects the degree (n) that makes am<2>+bm<2> maximum and adds it to an arithmetic device 17. On the other hand, a correction arithmetic device 18 to which Fourier coefficient of (m), (n) degree is added by the high speed Fourier transformer 12 determines the ratio of Fourier coefficient and finds out an error DELTAn. Then, the arithmetic device 17 adds (n) and DELTAn and displays the fundamental frequency on a display device 19. By this way, correct measurement can be effected without influenced by noise.
JP11070680A 1980-08-12 1980-08-12 Fundamental frequency measuring device Pending JPS5735764A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11070680A JPS5735764A (en) 1980-08-12 1980-08-12 Fundamental frequency measuring device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11070680A JPS5735764A (en) 1980-08-12 1980-08-12 Fundamental frequency measuring device

Publications (1)

Publication Number Publication Date
JPS5735764A true JPS5735764A (en) 1982-02-26

Family

ID=14542387

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11070680A Pending JPS5735764A (en) 1980-08-12 1980-08-12 Fundamental frequency measuring device

Country Status (1)

Country Link
JP (1) JPS5735764A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63183719U (en) * 1987-05-18 1988-11-25
JPH03240317A (en) * 1990-02-19 1991-10-25 Alps Electric Co Ltd Digital pll circuit
CN103048539A (en) * 2012-12-28 2013-04-17 南京工程学院 Accurate acquisition device and method of power frequency in audio forensics

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63183719U (en) * 1987-05-18 1988-11-25
JPH03240317A (en) * 1990-02-19 1991-10-25 Alps Electric Co Ltd Digital pll circuit
CN103048539A (en) * 2012-12-28 2013-04-17 南京工程学院 Accurate acquisition device and method of power frequency in audio forensics

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