关键词: 基音检测, 希尔伯特-黄变换, 经验模态分解

Abstract: According to the non-stationary and nonlinear time-varying characteristics of speech signal, a speech pitch detection method based on Hilbert-Huang transform is presented. It is unnecessary to assume that pitch period is stationary with in any segment, it can decompose signal adaptively and possess high time-frequency resolution（not subject to Heisenberg uncertainty principle）. Firstly, it uses the short-time energy to judge voice and unvoice, then the signal is decomposed into a number of intrinsic mode functions, with Hilbert transform, the instantaneous frequency and instantaneous amplitude of each intrinsic mode function are obtained, the components of the intrinsic mode functions are weighted to emphasize the fundamental frequency information according to the characteristics of pitch, lastly, the square of the autocorrelation is used to detect the pitch. Experiments show that compared with the classical methods, the proposed method provides a higher precision and better robustness.

Key words: pitch detection, Hilbert-Huang transformation, empirical mode decomposition