Probability of Error Analysis of 4-QAM OFDM Systems with Random Residual Frequency Offset

In this paper, we derive closed-form symbol error rate (SER) expressions for orthogonal frequency division multiplexing (OFDM) systems with residual carrier frequency offset (CFO). We treat CFO/residual CFO as a random parameter in this study. In particular, we consider channel-independent as well as channel-dependent random residual CFOs. We derive SER expressions for 4-quadrature amplitude modulation (4-QAM) OFDM systems in the cases of additive white Gaussian noise (AWGN) and frequency flat Rayleigh fading channels. The simulation results are provided to verify the accuracy of the new SER expressions.