Performance analysis of adaptive interleaving for MIMO-OFDM systems

In this paper, an adaptive interleaving scheme for multiple-input and multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems is proposed. The scheme could better exploit the instantaneous channel variation by rearranging the transmitted symbols according to the quasi-instantaneous channel SNR of the OFDM frame. The purpose is to break up a long burst channel error so that overall bit error probability is reduced. The upper bound of pair wise error probability (PEB) of the MIMO-OFDM systems is investigated. The code gain and diversity gain of the proposed scheme are given. The result shows that the major factor affecting performance of the proposed scheme is SNR, channel order and the number of receive antenna. Extensive simulations show that significant SNR can be obtained with the proposed scheme and the MIMO-OFDM case has a performance improvement over the single antenna case. Compared with block interleaving, for 2Tx-2Rx case at a BER of 10^-2, adaptive interleaving offers a 5 dB improvement.