Bit-interleaved space-frequency coded modulation with iterative decoding for OFDM systems

Abstract

We present a bit-interleaved space-frequency coded modulation (BI-SFCM) scheme with iterative decoding for orthogonal frequency-division multiplexing (OFDM) systems over frequency-selective channels. BI-SFCM is a space-frequency trellis coding method, based on bit-interleaved coded modulation (BICM) and multiple transmit and receive antennas. OFDM is used to transform a frequency-selective fading channel into multiple flat fading channels, and space-frequency trellis coding combined with bit-interleaving is used to exploit space and frequency diversity. BI-SFCM can provide increased data rates and improved performance. BI-SFCM with iterative decoding (BI-SFCM-ID) is proposed to further improve performance by means of increased coding gain by employing iterative decoding between the outer convolutional code and the inner space-frequency modulation. Analytical bounds and simulations are used to evaluate the performance of BI-SFCM-ID.