RESIDUAL ISI CANCELLATION FOR OFDM WITH APPLICATIONS TO HDTV BROADCASTING

An iterative technique is developed for orthogonal frequency division multiplexing (OFDM) systems to mitigate the residual intersymbol inter ference (ISI) that exceeds the length of the guard interval, The techn ique, called residual ISI cancellation (RISIC), uses a combination of tail cancellation and cyclic restoration and is shown to offer large p erformance improvements. The effects of imperfect channel estimation a re also considered, The RISIC algorithm is applied to a typical terres trial high-definition television (HDTV) broadcasting system that uses a concatenated coding scheme for error control. Results show that the RISIC algorithm can effectively mitigate residual ISI on static or slo wly fading ISI channels.