Fast time-varying channels in MIMO-OFDM system using different diversity technique

Multiple-input multiple-output (MIMO) technology and Orthogonal Frequency Division Multiplexing (OFDM) combinations provide robust to multipath delay and high data rates in wireless communication. The wireless connection of fast moving platforms leads to high demands for the applied transmission scheme. Therefore, a channel estimation technique using fast time-varying channel is proposed in this paper. The time varying channel may destroy the orthogonality among the subcarrier resulting in Inter-Carrier Interference (ICI). To cope with this problem, the ICI Self-cancellation (ICI-SC) technique is applied in a fast time varying channel using different types of diversity techniques such as space time block code (STBC), space frequency block code (SFBC) and space time-frequency block code (STFBC). Diversity techniques that exploit spatial time and frequency diversity can be designed using OFDM to reduce ICI as it is reliable in achieving maximum diversity. Thus, the objective of this paper is to evaluate BER performance using a Fast Time-Varying channel in MIMO-OFDM with ICI Self-Cancellation scheme using different diversity techniques. The simulation results show that using STFBC, the BER performance is the best compared to SFBC and STBC. In addition to that, ICI can be reduced and maximum diversity order with an efficient bandwidth can be achieved.