Frequency-Domain Equalization Incorporated with Frequency-Domain Redundancy for OFDM Systems

This paper proposes a frequency-domain equalizer (FEQ) which utilizes not only guard interval but also redundancy in the frequency domain to eliminate inter-symbol and inter-carrier interferences. The proposed FEQ employs the hybrid criterion, i.e., the zero-forcing (ZF) criterion for compensating desired subcarriers and the minimum mean square error (MMSE) criterion for suppressing interference. The proposed Hybrid-FEQ achieves a good equalization performance, because it can suppress the noise enhancement caused by the ZF criterion with relatively small computational complexity exploiting soft-decision forward error correction (FEC). In this paper, we show its equalization performance and complexity compared with the conventional FEQs.