Improved Sound-based Localization Through a Network of Reconfigurable Mixed-Signal Nodes

Abstract

There have been extensive theoretical studies on sound-based localization using pairs of microphones as well as microphone arrays. In contrast, there has been much less work on implementing and experimenting sound-based localization realized as customized electronic designs. This thesis presents a low cost implementation of a phase-based sound localization method. The implementation uses PSoC programmable mixed-signal embedded System on Chip, which incorporates microcontroller, on-chip SRAM and flash memory, programmable digital blocks and programmable analog blocks, all integrated on the same chip. The report presents a set of experiments to characterize the quality of localization using the proposed low-cost design.In addition, the thesis suggests a modification in the digital signal processing part through which Maximum Likelihood is replaced by an alternative method. The results for both these methods are then compared on the basis of accuracy, memory requirement and execution time. In order to improve the localization accuracy, filter corner frequency reconfiguration and gain reconfiguration is implemented. A wireless sensor network implementation is alsopresented. An extensive set of experiments are provided to explore the advantages of dynamic reconfigurability as well as the network implementation.