Complex spectrum circle centroid for microphone-array-based noisy speech recognition
Shigeki Sagayama, Takashi Okajima, Yutaka Kamamoto, Takuya Nishimoto · 2004
We propose a novel principle based on Complex Spectrum Circle Centroid (CSCC) for restoring complex spectrum of the target signal from multiple microphone input signals in a noisy environment. If noise arrives at multiple microphones with different time delays relative to the target signal, the observed noisy signals lie on a circle in the complex spectrum plane from which the target signal is restored by finding the centroid of the circle. Unlike most of existing methods for noise reduction such as ICA, AMNOR and beamforming, this nonlinear operation is applicable to any type of noise including non-stationary, moving, signal-correlated, nonplanar, and spoken noises, without identifying the noise direction and training parameters.