Colloquium - Details
You will receive information about presentations in time if you subscribe to the newsletter of the Colloquium Communications Technology.
Master-Vortrag: Personalized Occlusion Cancellation in Headphones and Hearing Aids
Mittwoch, 6. Januar 2021
To users of headphones, hearables, and hearing aids, the occlusion effect (OE) is still a largely unsolved problem that causes them to perceive the sound of their own voice differently. In surveys, users commonly describe this OE-affected own-voice sound as hollow, boomy, and unpleasant. Other body-conducted sounds are affected as well; examples include the noise originating from footsteps or chewing.
A system that actively combats this effect has been in active development at the Institute of Communication Systems. This so-called Active Occlusion Cancellation (AOC) system is designed to cancel the average OE when applied to the average user’s occluded ear. Acoustic measurements as well as a listening test have shown it to be able to significantly reduce the OE and improve the users’ subjective experience. Unfortunately, both the OE and the acoustic characteristics of the occluded ear can vary significantly from user to user. That is why this thesis sets out to explore approaches to personalize the AOC system for individual users.
First, an objective scalar metric for the OE is proposed. This metric is then used to automatically adjust two scalar gains already present in the AOC system. These gains allow for a limited degree of personalization and, up until now, had to be adjusted manually. Second, a technique to iteratively design a personalized feedback controller based on a user’s acoustic measurements is introduced. This feedback controller is a major part of the AOC system. For the limited amount of user measurements that are available, this new design technique manages to quickly and reliably converge onto a controller that meets both the performance and robustness requirements. The controller design process is fully automated and does not require manual intervention by a control engineer. Finally, both personalization approaches are evaluated in a listening test of limited scope and size due to the ongoing COVID-19 pandemic.
Alle Interessierten sind herzlich eingeladen, eine Anmeldung ist nicht erforderlich.