Patent ID: 7493254

Claim:
A method of detecting a pitch using frequency analysis, comprising: a first step of analyzing an externally input digital signal into frequency component values at predetermined time intervals and detecting positions of peaks of the digital signal based on the frequency component values; a second step of selecting a maximum peak position from the detected peak positions, determining whether a frequency at the maximum peak position is a pitch or an n-order harmonic frequency of the pitch, and detecting the pitch based on the result of the determination; and a third step of detecting a position of a harmonic frequency of the pitch determined in the second step and determining the range of the pitch based on the range of the harmonic frequency, wherein the third step comprises: calculating a frequency range F 1 of the pitch determined in the second step; calculating a frequency range F 2 by dividing the range of a harmonic frequency positioned at an h-th place from the pitch among harmonic frequencies, which can be detected with respect to the pitch, by “h”; and determining an intersection between the frequency range F 1 and frequency range F 2 as the range of the pitch.