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Abstract Aim of this project was to analyse signals and try to localize the position of source of sound. It is done with three microphones which have 90 degrees angle to each other. Each microphone detects one part of the sound wave. The microphones are connected toan ADC which turns signals from an...

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Bibliographic Details
Main Author: Moradi, Hamid
Format: Others
Language:Swedish
Published: Högskolan i Gävle, Institutionen för teknik och byggd miljö 2008
Subjects:
Online Access:http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-3059
Description
Summary:Abstract Aim of this project was to analyse signals and try to localize the position of source of sound. It is done with three microphones which have 90 degrees angle to each other. Each microphone detects one part of the sound wave. The microphones are connected toan ADC which turns signals from analogue to digital shape. After that the three signals are transformed to a computer. As known a computer receives only digital signals which are the main reason to use the ADC. The signals are analysed by computer with help of special softwares. These softwares are LabVIEW and MATLAB which are used in this work. This analysis of the signals is divided in two parts. The first part is the FFT-analyse (Fast Fourier Transform) of the signal from the microphones. It means that the signals frequency’s domain is showed, in other word it shows which frequency components a signal has. Then the result is showed online by a function belonging to LabVIEW which is called Web Publish. In second part the position of the signal source is determined by cross correlation. The position is determined by the difference of time between two signals from same source which are measured by cross correlation and you can determine angle by triangulating which is described in report.