An approach to co-channel talker interference suppression using a sinusoidal model for speech

The technique fits a sinusoidal model to additive vocalic speech segments such that the least mean square error between the model and the summed waveforms is obtained. Enhancement is achieved by synthesizing a waveform from the sine waves attributed to the desired speaker. Least squares estimation is applied to obtain sine-wave amplitudes and phases for both talkers, based on either a priori sine-wave frequencies or a priori fundamental frequency contours. When the frequencies of the two waveforms are closely spaced, the performance is significantly improved by exploiting the time evolution of the sinusoidal parameters across multiple analysis frames. The least squares error approach is also extended to estimate fundamental frequency contours of both speakers from the summed waveform. The results obtained, though limited in their scope, provide evidence that the sinusoidal analysis/synthesis model with effective parameter estimation techniques offers a promising approach to the problem of cochannel talker interference suppression over a range of conditions