Space-Aware Hearing Aid
Space-Aware Hearing Aid
Space-aware hearing aid
The "space-aware hearing aid"-demonstrator is a real-time capable and wearable hearing system that includes the Research Unit’s developments for hearing aid technology, featuring contributions from TP A, C and F.
The Demonstrator is based on the acoustically transparent earpiece hardware which is operated using a custom adaptor box, a standard sound card and portable mini NUK computers. Subjects can wear the live hearing system in the ear, all other equipment fits inside a small backpack.
The space-aware hearing aid is a research platform that is permanently further developed, updated and extended by new functionalities The functions already included and/or planning to be incorporated in the demonstrator are:
Binaural open-fitting transparent hearing aid-headset
Sound quality optimization by individualized sound pressure equalization: The hearing -aid headset can be calibrated in-situ to produce an equivalent frequency response at the eardrum as the open ear – hence, the device becomes “acoustically transparent”. By this feature, unnatural distortions are equalized and the sound impression becomes more natural. This individualized hardware platform forms the basis of the demonstrator. More infos can be found here.
Scene analysis: source localization, tracking
Source localization is the first step of scene analysis conducted in the demonstrator. Estimation of source locations, i.e., direction of arrival relative to the observer, is based on spatial source probability maps that are estimated in 10ms time frames on the acoustic input channels of the earpieces. The spatial source image, provided by the probabilistic maps, is available in the whole angular range of interest at the same time. The probabilistic information of sound source presence enables tracking of sources in dynamic scenarios. Different mechanisms taking into account reliability of estimates as well as physical properties of (moving) acoustic sources are implemented.
Noise reduction: Steerend Binaural Beamformer
Work in progress.
Individualized feedback cancellation
In order to be able to provide the necessary amplification, acoustic feedback cancellation algorithms are integrated which combine individualized null-steering and adaptive feedback cancellation. First the acoustic feedback paths between the loudspeaker and the microphone(s) are measured using a probe-noise. These measurements are used to compute individualized filters, which in combination with an adaptive filtering algorithm (based on the state-of-the-art prediction-error-method), are then used for feedback cancellation.
Interactive gesture-based user control: source selection
Work in progress.
Hearing loss compensation
Work in progress.