Scientific paper ID 868 : 2013/3

This publication describes the developed software tool with graphical user interface for simulation study of amplitude modulation, which will be used in the course “Communication Circuits” d as compulsory in the curriculum of the specialty “Telecommunication Systems” for the “Bachelor” educational qualification degree in University of Ruse “Angel Kanchev”. The tool is implemented using MATLAB and GUIDE (Graphical User Interfaces Development Environment). The application allows the visualization of the carrier, modulating and amplitude-modulated signal in the time and the frequency domains with modulation using one, two or three frequencies of the modulating signal, and given parameters of the carrier and the modulating signal. It allows the mathematical model of amplitude-modulated signal to be displayed in a separate graphical window. There is a possibility for calculating the power emitted in the “silence” mode (when the modulating signal is not available), the power of the upper/lower side-band, as well as the total power at a given resistance. The cases of Double Side-Band Suppressed-Carrier Amplitude Modulation and Single Side-Band Suppressed-Carrier Amplitude Modulation are discussed. Information about the amplitude modulation, amplitude modulation types, their advantages and disadvantages is intended to be displayed in a separate graphical window. The developed application aims to increase students’ interest in studying the course “Communication Circuits”.