A robust multichannel speech enhancement method based on decorrelation

The paper introduces a scheme that combines blind signal separation (BSS) and adaptive noise cancellation (ANC) to enhance a speech signal under the influence of noise. The main idea is to exploit the "blindness" (no array geometry or source localisation information) of BSS whilst boosting its suppression performance temporally. Initially, the scheme spatially decorrelates the received signal, i.e. BSS separates the target signal from interference using the L observed inputs. Then, the target signal is further temporally decorrelated through the ANC to remove any residual noise. It is observed that the proposed method compensates for the separation limitation of BSS to remove non-directive components. Evaluations in a real room show that the scheme offers an impressive noise suppression up to 20 dB with only a few microphones.