DATA TRANSMISSION USING HIERARCHICAL MODULATION OVER A MOBILE WIRELESS CHANNEL

Abstract

This project is about the modeling and simulation of data transmission (picture or video) ,using hierarchical modulation over a mobile wireless channel characterized by Rayleigh fading, Additive White Gaussian Noise (AWGN) and shadowing with two-Antenna diversity selection for system improvement. The objectives are to determine which modulation technique will be best suitable- Quadrature Amplitude Modulation (QAM) or Phase Shift Keying(PSK), the maximum level of modulation as well as switching decisions that will meet the Bit Error Rate (BER) target of 10-3,and choosing between uncompressed and compressed transmission of data(images or video) through the channel. The entire modelling and simulation is done using Matlab and Simulink software. Result shows QAM’s poor performance and irreducible bit error rate, and extremely great distortion when compressed data is being transmitted. From the result, conclusions can be drawn that PSK performs better than QAM over the channel and that uncompressed data transmission over the channel is better in terms of error sensitivity and since uncompressed images and video was able to be enhanced appreciably using median filtering.