A Novel Simulation Model for Coded OFDM in Doppler Scenarios

This paper proposes a novel simulation model to characterize the bit-error rate (BER) performance of coded orthogonal frequency-division multiplexing (OFDM) systems that are affected by the Doppler spread. The proposed equivalent frequency-domain OFDM model (EFDOM) avoids the exact generation of the time-varying channel by introducing several parameters that summarize the statistical properties of the channel and of the intercarrier interference (ICI) that is generated by the time variation of the channel. Simulation results are used to prove that the proposed model can be used to accurately predict the BER of coded OFDM systems in Rayleigh and Rice doubly selective channels. An attractive feature of the proposed model is the significant reduction of the simulation time with respect to the exact model. We show by simulation that the simulation efficiency increases for channels with many multipath components, whereas it is independent of the size of the fast Fourier transform (FFT).