Instantaneous Binaural Target PSD Estimation for Hearing Aid Noise Reduction in Complex Acoustic Environments

Some hearing aid models such as the in-the-ear or in-the-canal model are small, and due to size constraints, only a single microphone per hearing aid can be fitted. As a result, only the single-channel noise reduction schemes can be integrated in them. However, in the near future, binaural hearing aids will be available. These hearing aids will allow hearing devices on each side of the head to receive information from the microphones located on both devices via a wireless link. This additional information allows the use of joint statistics and/or spatial information, which allows the use of better denoising methods. The main contribution of this paper is to introduce a binaural target power spectral density (PSD) estimator for binaural hearing aids under the presence of a background interfering talker (or a lateral transient noise). This paper then presents an example of how the proposed target PSD estimator and another recently developed binaural diffuse noise PSD estimator can be integrated to produce a binaural noise reduction scheme that can operate in real-life complex acoustic environments that are composed of time-varying diffuse noise, multiple directional nonstationary talkers (or noises), and reverberant conditions. Such a binaural noise reduction system allows the substantial reduction of different combinations of diverse background noises and the increase in speech intelligibility while guaranteeing the preservation of the interaural cues of both the target speech and the directional background noises. A comparison with several advanced denoising algorithms is made in this paper by using several objective measures and real-life hearing aid signals, showing the good performance of the example binaural noise reduction scheme that uses the proposed PSD estimator.