Simulation Analysis of Information Transmitting Mechanism Based on Amplitude Modulation Technique

Abstract

This paper has presented simulation analysis of information transmitting mechanism based on amplitude modulation (AM) technique. In AM technique, the amplitude of carrier signal is varied in proportion to the continuous time amplitude of the message signal. The study has modelled an AM modulating and demodulating system in MATLAB/Simulink environment. Three different scenarios were considered in terms of varying modulation index. The values of modulation indices selected are 1, 0.5 and 1.5 representing perfect, under and over modulations respectively. The results indicated that at modulation indices of 0.5and 1, the modulating signals produced no distortion. However, selecting a modulation index of 1.5produced distortion in the transmitted information and as such choosing a modulation index of above one will not be suitable in the transmission of information in AM system.