Title:
FUNDAMENTAL FREQUENCY ESTIMATION DEVICE, ACTIVE NOISE CONTROL DEVICE, FUNDAMENTAL FREQUENCY ESTIMATION METHOD, AND FUNDAMENTAL FREQUENCY ESTIMATION PROGRAM
Document Type and Number:
WIPO Patent Application WO/2021/193637
Kind Code:
A1
Abstract:
The present invention avoids delays occurring along with a fast Fourier transform and accurately estimates a fundamental frequency with little computation and few delays. Input signals are sequentially acquired, and, each time a sample point in an input signal is acquired, a recurrence formula which includes the previous value of the sample point is used to calculate the amplitude spectrum of the input signal, and the peak frequency of the amplitude spectrum is extracted. Furthermore, each time a sample point is acquired, a bandwidth that includes the peak frequency of an amplitude spectrum is emphasized. Then a recurrence formula that includes the previous value of an autocorrelation function is used to calculate the autocorrelation function, and the peak frequency of the autocorrelation function is set as a fundamental frequency.
Inventors:
OKAWA RYOTA (JP)
Application Number:
PCT/JP2021/012001
Publication Date:
September 30, 2021
Filing Date:
March 23, 2021
Export Citation:
Assignee:
TRANSTRON INC (JP)
International Classes:
G10G3/04; G10K11/178; G10L21/02; G10L25/90
Foreign References:
| JP2008281776A | 2008-11-20 | |||
| JP2014219607A | 2014-11-20 | |||
| JP2000298475A | 2000-10-24 | |||
| JPH06110497A | 1994-04-22 | |||
| JPS61187000A | 1986-08-20 | |||
| US20080091418A1 | 2008-04-17 |
Attorney, Agent or Firm:
SAKATA Yukari (JP)
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