Speech enhancement using modified phase opponency model

We previously presented a single-channel speech enhancement technique called the Modified Phase Opponency (MPO) model. The MPO model is based on a neural model called the Phase Opponency (PO) model. The efficacy of the MPO model was demonstrated on speech signals corrupted by additive white noise. In the present work, we extend the MPO model to perform efficiently on speech signals corrupted by additive colored noise with time varying spectral characteristics and amplitude levels. The MPO enhancement scheme outperforms many of the statistical and signaltheoretic speech enhancement techniques when evaluated using three different objective quality measures on a subset of the Aurora database. The superiority of the MPO speech enhancement scheme in enhancing speech signals when the amplitude level and the spectral characteristics of the background noise are fluctuating is also demonstrated.