Publication Abstract

Quatieri, T.F., and McAulay, R.J., Noise Reduction Using a Soft-decision Sine-wave Vector Quantizer, Proc. IEEE Int. Conf. Acoustics, Speech, and Signal Processing, Albuquerque, New Mexico, April 1990.

Abstract

The need for noise reduction arises in speech communication channels, such as ground-to-air transmission and ground-based celluar radio, to improve vocoder quality and speech recognition accuracy. In this paper, noise reduction is performed in the context of a high-quality harmonic zero-phase sine-wave analysis/synthesis system which is characterized by sine-wave amplitudes, a voicing probability, and a fundamental frequency. Least-squared error estimation of a harmonic sine-wave representation leads to a "soft decision" template estimate consisting of sine-wave amplitudes and a voicing probability. The least-squares solution is modified to use template-matching with "nearest neighbors." The reconstruction is improved by using the modified least-squares solution only in spectral regions with low signal-to-noise ratio. The results, although preliminary, provide evidence that harmonic zero-phase sine-wave analysis/synthesis, combined with effective estimation of sine-wave amplitudes and probability of voicing, offers a promising approach to noise reduction.