Wiener-based ICI Cancellation Schemes for OFDM Systems over Fading Channels

Jyh-Horng Wen, Yung-Cheng Yao, Ying-Chih Kuo

The subcarriers of orthogonal frequency division multiplexing (OFDM) systems may fail to keep orthogonal to each other under time-varying channels. The loss of orthogonality among the subcarriers will degrade the system performace, and this effect is named intercarrier interference (ICI). In this paper, a Wiener-based successive interference cancellation (SIC) scheme is proposed to detect the OFDM signals. It provides good ICI cancellation performance; however, it suffers large computation complexity. Therefore, a modified Wiener-based SIC scheme is further proposed to reduce the computation complexity. Simulation results show the performance of the Wiener-based SIC scheme is better than those of zero forcing, zero forcing plus SIC and original Wiener-based schemes. Furthermore, with the modified Wiener-based SIC scheme, the performance is still better than the others. Although the performace of the modified Wiener-based SIC scheme suffers little degradation compared to Wiener-based SIC scheme, the computation complexity can be dramatically reduced.