PERFORMANCE OF ORTHOGON AL FREQUENCY DIVISION MULTIPLEXING (OFDM) UNDER THE EFFECT OF WIRELESS TRANSMISSION SYSTEM DRAWBACKS

Abstract

Orthogonal Frequency Division Multiple xer (OFDM) technology is a key technique for achieving the high dat a rate and spectral efficiency requirements for wireless communicati on systems of the near future. This paper presents a modeling and simulati on of OFDM by MATLAB& Simulink. Different modulation schemes hav e been used, such as BPSK, QPSK, DBPSK, DQPSK, 8PSK and 16PSK. The paper concentrated on Differential Quadrature Phase Shift Keying (DQPSK) as a modulation scheme since it achieved high data rate and very good per formance. As part of this, an investigation of detrimental effe cts of wireless transmission system drawbacks on OFDM is presented, showing the effect of band pass filtering, Additive White Gaussian Noise (AWGN) on modulation Bit Error Rate (BER). The paper also presents how OFDM deal with other transmission drawbacks such as attenuation, multipath, delay spread and Doppler shif