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The deployment of 5G and 6G wireless networks enforces a paradigm shift in communication system design, driven by the move towards sub-THz frequencies and extremely large antenna arrays. These advancements leave traditional channel modeling—which often relies on far-field assumptions and neglects electromagnetic interactions between antenna elements—physically inconsistent. Furthermore, the overhead associated with acquiring instantaneous channel…

This dissertation focuses on Kronecker compressed sensing, recovering multidimensional sparse signals from their linear projections on Kronecker product measurement matrices. Multidimensional signals are functions of different dimensions, each conveying a specific physical quantity and they arise in applications such as wireless communications and image processing. Kronecker product matrices naturally capture the multidimensional nature, making Kronecker…

In everyday communication scenarios, such as meetings and social gatherings, undesired interfering speakers and background noise often degrade the quality and intelligibility of the desired target speaker. Various approaches have been developed to address this issue, such as blind source separation and speaker-conditioned target speaker extraction (SC-TSE). SC-TSE algorithms aim at extracting the desired speaker…

In recent years, hearable technology has advanced rapidly, leading to widespread daily use in challenging acoustic environments. As their popularity has grown, so has the demand for high-quality speech communication. Although hearables can capture the user’s own voice with outer microphones, recordings made in noisy conditions typically require processing to enhance speech quality, which can…

Biometric recognition systems tend toward ubiquity and are widely being used in different applications for authentication purposes. Compared to conventional authentication tools, such as PIN or password, which are always in danger of being forgotten or stolen, biometric authentication offers excellent convenience for the user. In contrast, in addition to security threats, biometric systems are…

In many speech communication devices, such as smartphones, smartspeakers, and hearing devices, the microphones capture not only the target speaker but also undesired ambient noise, degrading speech quality and speech intelligibility. Speech enhancement algorithms aim at extracting the target speech from the recorded microphone signals by suppressing noise while not distorting the target speech. Over…

Augmented reality (AR) and telepresence systems aim to enhance the real world with virtual elements that blend convincingly into the surrounding space. Creating virtual sound sources in this context requires presenting perceptually valid head-related and room-acoustic cues to the listener to enable a realistic spatial impression and a coherent match between the virtual acoustics and…

This PhD thesis explores the field of scene understanding using sound through artificial intelligence techniques. It addresses the challenge of extracting relevant information from sound in environments where other sensory inputs, such as vision, are limited or occluded. The work contributes novel methods and models for Acoustic Scene Classification (ASC), Sound Event Detection (SED), Unsupervised…

Distributed machine learning for Internet of Things (IoT) and cyber-physical systems (CPS) applications faces increasing demands for efficiency, privacy, and robustness. This thesis focuses on addressing these challenges through two primary approaches, i.e., fully-distributed learning algorithms and federated learning (FL) algorithms, which form the main contributions of the work. This study proposes machine learning algorithms…

Automatic music transcription (AMT) is a core task in music information retrieval, aiming to convert audio recordings of musical performances into human- or machine-readable score formats. AMT has various applications, including music search, analysis, tutoring, and generation. While AMT research has traditionally focused on note-level transcription, i.e., generating mid-level representations such as piano rolls or…