Author(s)

Yosuke Sugiura, Arata Kawamura, Youji Iiguni

Graduate School of Engineering Science, Osaka University, Osaka, Japan.

In this paper, we analyze an inverse notch filter and present its application to F₀ (fundamental frequency) estimation. The inverse notch filter is a narrow band pass filter and it has an infinite impulse response. We derive the explicit forms for the impulse response and the sum of squared impulse response. Based on the analysis result, we derive a normalized inverse notch filter whose pass band area is identical to unit. As an application of the normalized inverse notch filter, we propose an F₀ estimation method for a musical sound. The F₀ estimation method is achieved by connecting the normalized inverse notch filters in parallel. Estimation results show that the proposed F₀ estimation method effectively detects F₀s for piano sounds in a mid-range.

Band Pass Filter; Inverse Notch Filter; Impulse Response Analysis

Y. Sugiura, A. Kawamura and Y. Iiguni, "Performance Analysis of an Inverse Notch Filter and Its Application to F₀ Estimation," Circuits and Systems, Vol. 4 No. 1, 2013, pp. 117-122. doi: 10.4236/cs.2013.41017.