Giuliano Bernardi

Research

Signal Processing Algorithms for Implantable Hearing Instruments

Whenever a microphone captures a desired sound signal, which is then processed (e.g., amplified) and played back by a loudspeaker in the same environment, the loudspeaker signal is unavoidably fed back into the microphone.

In this way, a closed signal loop is created which may readily become unstable, deteriorating the sound quality and limiting the achievable amplification.

Among the different artifacts that are produced by this acoustic coupling, the howling effect is no doubt the most characteristic one. Acoustic feedback control refers to the process of attempting to cancel the acoustic feedback either completely (i.e., to remove the acoustic coupling) or partially (e.g., to remove the howling artifacts from the loudspeaker signal).

The aim of this project will be to first characterize the feedback path in novel hearing instruments, in particular the direct acoustic cochlear implant (DACI) system, and to study the applicability of existing feedback control procedures as well as develop novel improved procedures.

In particular, the adaptive feedback cancellation (AFC) based approach will be studied and necessary modifications will be designed. A complexity versus performance trade-off study will be performed, with the aim of reducing the algorithmic complexity to a manageable level.

Biography

Giuliano Bernardi was born in Asolo, Italy in 1987. He obtained a Bachelor of Engineering (BEng) in Biomedical Engineering from the University of Padua, IT in 2009. After completing his degree, he won a scholarship from the T.I.M.E. network for a three-year joint-degree program from the University of Padua and the Denmark Technical University (DTU), DK.
For two years he was a student at DTU, where he graduated in 2011 obtaining a Master of Science (M.Sc.) in Engineering Acoustics. Afterwards, he moved back to Italy to conclude his studies at the University of Padua and in 2012 he obtained a Master of Engineering (MEng) in Bioengineering.
In February 2018, Giuliano obtained the Ph.D. in engineering science from KU Leuven, Belgium, working in the STADIUS Research Division within the KU Leuven Department of Electrical Engineering. His Ph.D. project focused on acoustic feedback reduction, specifically for the hearing-aid domain.

Currently, he is a Postdoctoral Researcher at KU Leuven focusing on acoustic feedback control and noise reduction strategies for hearing-aid applications. His research interests include audio signal processing, speech perception and psychoacoustics, real-time audio signal processing, and speech enhancement.

Finished projects

• Cooperative Signal Processing Solutions for IoT-based Multi-User Speech Communication Systems
• Cochlear-VII - Advances in Auditory Implants: signal processing and clinical aspects

Publications