The performance of high order modulation QAM-OFDM in the presence mutipath fading channels

Abstract

The limited amount frequency spectrum available to wireless communication systems makes it difficult to satisfy the rapidly growing demand for wireless service. Spectral efficiency can be increased by using higher order modulation schemes. However this come at the cost of increased probability of error. In this paper we investigate through MATLAB simulation, the implementation of orders of Quadrature Amplitude Modulation (QAM) more commonly used in wired networks. The BER performance of 256, 512, 1024, 2048, and 4096 QAM-Orthogonal Frequency Division Multiplexing(OFDM) signals in the presence of Rayleigh and Rician multipath channels with additive white Gaussian noise are simulated.