OFDM and FBMC performance comparison for multistream MIMO systems

A comparison between two multicarrier (MC) transmission techniques is presented: OFDM, based on cyclic prefix (CP), and FBMC, based on filterbank architecture. Multistream multiple input multiple output (MIMO) techniques that require channel state information (CSI) at the transmitter and receiver, are applied in these schemes to improve their throughput. When perfect CSI is assumed, OFDM presents lower energy-efficiency than FBMC due to the use of the CP. However, unlike OFDM, the use of multiple streams increases interference in FBMC. When imperfect CSI is considered, while there is neither inter-symbol interference (ISI) nor inter-carrier interference (ICI) in OFDM, FBMC still suffers this effect. In scenarios with low coherence bandwidth channels, the performance of FBMC degrades due to a significant increase in interference. On the contrary, OFDM is shown to be more robust in such scenarios. In this paper, we explore analytically and by means of simulation, the sources of errors together with the effects of channel coherence bandwidth and the energy-efficiency trade-off observed for both systems.