Linear equalization of the modulation spectra: a novel approach for noisy speech recognition

The paper tackles the problem of noisy speech recognition. In particular, we present a novel approach to the design of filters for processing the modulation spectrum, that we call linear equalization. We postulate that, as long as the distortion of the spectral parameters due to noise can be modeled as linear, an advantageous solution consists of estimating this linear perturbation system and designing its inverse system (the equalizer). Our experimental results show that the proposed method is very effective for three of the five types of noise considered.