Adaptive interleaving for OFDM in TDD systems

The authors propose a novel interleaving technique, namely adaptive interleaving, which can break the bursty channel errors more effectively than traditional block interleaving. This new scheme resequences the transmitted symbols adaptively, according to the instantaneous subcarrier channel state information. In this way, the bursty errors introduced by the channel can be broken more effectively, thus a better BER performance can be achieved. This technique is well suited to OFDM systems, because the CSI values of the whole frame could be estimated at the same instant when transmitted symbols are framed in the frequency dimension. Computer simulation shows that significant SNR gains can be achieved, compared with traditional block interleaving.