A low-complexity iterative detector for COFDM in mobile channels

Recently, it has been shown that the received signal in the OFDM systems can be viewed as the synchronous code-division multiple access (SCDMA) signal in receiver after some mathematical manipulation, and the ICI term in the OFDM system is equivalent to the multiple access interference (MAI) term in synchronous CDMA system. They proposed a successive interference cancellation multicarrier detector and it performs better than conventional single-carrier detection schemes in time-varying multiple channel (Doppler≠0). To further improve the performance of OFDM systems in the presence of ICI, we propose to use a soft-in soft-out (SISO) multicarrier detector and a SISO convolutional decoder in an iterative (turbo) way. The simulation results show that the first iteration of the proposed scheme demonstrates 2-3 dB gain compared to the previous multicarrier detection schemes.