Performance of multiresolution OFDM on frequency-selective fading channels

Several multiresolution modulation (MRM) schemes with orthogonal frequency division multiplexing (OFDM) are examined. The effect of interchannel interference (ICI) caused by channel time variation and carrier frequency offset Is considered, The performances of the multiresolution schemes for both uncoded and trellis-coded systems are evaluated in terms of their bit error rate (BER), degree of prioritization, and decoding complexity. Finally, applications to high definition television (HDTV) broadcasting are considered, where a concatenated coding scheme is employed to provide the required performance levels.