Spatial filtering based speech enhancement for binaural hearing aid

This paper investigates a new two-microphone array processing technique specifically for the purpose of speech enhancement in binaural cochlear implant. The main objective of the proposed technique is to improve the low frequency directivity of a conventional sum and delay Beamformer without using a generalized lobe canceller, as low frequency performance is critical in speech processing applications. The proposed beamformer algorithm based speech enhancement allows receiving a speech signal radiating from a specific direction and attenuating the signals from the other direction. Indeed, the localization of the speech target is defined, especially, with two cues of the speech signal received by the both ears: The interaural intensity difference (IID) and the interaural time difference (ITD). Adapting these parameters allows not only better localization of the interest direction of the speech and noise component but enhancing the signal-to-noise ratio also.