Evaluation of orthogonal frequency‐division multiple‐access systems in the presence of carrier frequency offset using wireless images transmission

Abstract

AbstractOrthogonal Frequency‐Division Multiple‐Access (OFDMA) is used in different recent wireless communication systems. However, it is susceptible to carrier frequency offset (CFO) which effects the orthogonality between subcarriers and causes inter‐carrier interference (ICI) and multiple access interference (MAI). The aim of this paper is to analyze the impact of the CFOs on the performance of Discrete Sine Transform (DST) DST‐OFDMA, Discrete Cosine Transform (DCT) DCT‐OFDMA and Discrete Fourier Transform (DFT) DFT‐OFDMA systems and to evaluate them with different modulation schemes and different subcarriers mapping schemes over vehicular A and Stanford University Interim (SUI) 3 channels. Transmission of image over the wireless system is performed to analyze and investigate the performance in terms of the Peak Signal‐to‐Noise Ratio (PSNR), and the Mean Square Error (MSE). Through the evaluation, with CFO compensation, without CFO, and without CFO compensation cases are considered. In this work, Joint Minimum Mean Square Error (JMMSE) equalization and CFO compensation technique is used. It is noted that when the QPSK scheme and the SUI3 channel model are used then the DCT‐OFDMA system provides better MSE and PSNR performances than other systems for the JMMSE compensation technique.