Noise suppressor using zero phase signal and temporal accumulation technique

This paper proposes a wide-band noise reduction method using temporal accumulation and zero phase (ZP) signal. By replacing the ZP signal around the origin with the ZP signal in the second or latter period to get an estimated speech ZP signal, this method can reduce both stationary and non-stationary wide-band noises without a prior estimation of the noise spectral amplitude However, for very low SNR environment, reliable period estimation is difficult. This paper presents a study of period estimation in noisy speech based on temporal accumulated zero phase signal (TAZPS) representation. Since harmonic structure of speech changes much more slowly than noise spectrum, spectral peaks related to period harmonics would stand out over the noise through the accumulation. In this paper, we combine pitch estimation based on temporal accumulated ZP signal and noise suppressor. Simulation results show that the proposed noise reduction method further improves the SNR especially in a low SNR environment.