Σχεδιασμός και υλοποίηση ενσωματωμένου συστήματος ψηφιακού Delay - Echo για ακουστικό σήμα

Master Thesis
Author
Μίσκας, Θωμάς Δ.
Date
2011-09-30View/ Open
Subject
Σχεδιασμός συστημάτων ; Embedded computer systems -- Design and construction ; Επεξεργασία σημάτωνAbstract
The aim of this thesis ist the design and implementation of an embedded system, that is capable of processing in real time an acoustic signal, in order to produce a Delay-Echo effect. This kind of digital audio effect is useful, both to musicians and sound engineers. The goal of this system is to create a more realistic sound during recording sessions in a studio. Moreover, it can be used as an interesting musical effect. The prototype consists of a digital and an analog subsystem. The digital subsystem includes a microcontroller and two serial signal converters: an analog to digital (ADC) and a digital to analog one (DAC). The analog subsystem is composed of two identical low pass filters. The first one is placed in front of the ADC as an antialiasing filter, while the second one filters the output of the DAC. The system is based on the “Propeller” microcontroller. The fact that this is not a Digital Signal Processor (DSP) consisted not only an additional constraint but also an algorithm challenge which was successfully handled.