ABSTRACT
In this chapter, we first propose an MC coded OFDM system by simply inserting one or more zeroes between each two sets of K consecutive information symbols, which may be independent of the ISI channel. However,
the MC can be general. Notice that, due to the insertion of zeroes, the data rate is expanded in the MC coded OFDM systems. We show that, for spectral null channels the MC coded OFDM systems perform better than the existing OFDM systems do even when the conventional convolutional codes and TCM are used in the OFDM systems, i.e., COFDM systems [189, 188, 47]. The rationale is that the proposed MC coded scheme may be able to remove the spectral nulls of an ISI channel without even knowing the channel information. Furthermore, the proposed MC coded OFDM system does not increase the encoding/decoding complexity as much as the conventional COFDM does, where the Viterbi decoding for the conventional COFDM is needed.
