Sound zone algorithms control the inputs to a loudspeaker array such that spatially distinct zones, each with separate audio content, are created. This work proposes a sound zone approach which includes a model of human auditory perception in the optimization problem designing the loudspeaker control filters. The control filters are therefore optimized directly for human experience, rather than by proxy through sound pressure, as is done in typical approaches. The proposed optimization problem features a perceptually weighted constraint on the bright zone reproduction error, which allows the user of the algorithm to specify the desired bright zone quality. The proposed method achieves 2 to 4 dB of additional acoustic contrast and is expected to yield less distracting dark-zone interference for the same perceived quality when compared to a traditional approach.

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With the aid of an array of loudspeakers, sound zone algorithms seek to reproduce multiple distinct zones of audio inside an enclosure. Typical approaches determine the loudspeaker inputs by optimizing over a cost function that models the sound pressure inside the enclosure. However, recent methods propose cost functions that include a perceptual model of the human auditory system, which further models the perception of sound. This thesis investigates such an approach by proposing a framework within which sound zones are constructed through optimization over a perceptual model. The framework is used to propose two perceptual sound zone algorithms: unconstrained and constrained perceptual pressure matching. Simulations of the proposed algorithms and a reference algorithm are presented to determine the benefits of including auditory-perceptual information in sound zone algorithms. From this, it is found that the unconstrained perceptual approach outperforms the reference in terms of various perceptual measures. In addition, it is found that adding perceptual constraints to the optimization problem allows for control of sound zones which correlates well with other perceptual quality measures.

This report details the design and implementation of a subsystem within a localization system designed for the Bosch DICENTIS wireless conference system. The goal of this localization system is to determine the location of individual units. These units each contain a microphone and a loudspeaker and are used by the participants at a conference. Potential use cases for the locations of these units are beam-forming and the mapping of participants within a room.

The subsystem discussed in this report is tasked with transforming estimated propagation times of audio signals into locations of the units. To this end, a TOA-based and a TDOA-based algorithm for the self-localization of individual conference system units is presented. Experimental results show that both methods are able to recover positions, with the TOA-based method slightly outperforming the TDOA-based method. Real-life measurement results show a root mean square error in position of about 8 cm for the TOA-based method.