Performance comparison of OFDM and OFDM/OQAM systems operating in highly time and frequency dispersive radio-mobile channels

In this paper, we compare the performances of both conventional OFDM and OFDM/OQAM systems, in terms of SIR, in time and frequency dispersive channels. We start by deriving analytical expressions of the SIR for OFDM/OQAM systems, for two reception approaches: the multiplicative approach and the dispersive approach. The former approach, which is based on a multiplicative modelling of the channel, is the conventional reception way. The dispersive approach is based on matched filtering and provides an optimum reception in the presence of thermal noise. These expressions and other well known expressions of the SIR for conventional OFDM are then confirmed by simulation. Our results show that OFDM/OQAM systems, based on the IOTA waveform, provide better robustness to channel dispersions with respect to conventional OFDM systems.