Coding strategies for OFDM with antenna diversity high-bit-rate mobile data applications

In this paper, we investigate coding strategies for an OFDM system with antenna diversity. To maximize coding efficiency, interleaving in the two-dimensional frequency-time domain is studied. In particular, transmission over multiple antennas, which achieves an interleaving effect by randomizing the fading over the subchannels, is employed. Based on the best interleaving method, we consider convolutional coding and compare its performance with that of Reed-Solomon coding. Simulation results indicate that a 1/2-rate convolutional code requires a constraint length of at least 6, with soft decisions, to achieve better performance than a 1/2-rate (40,20) Reed-Solomon code with 6-bit symbols and a combination of erasure and error correction. In addition, a concatenated coding scheme, combining convolutional and Reed-Solomon coding, is presented and is shown to achieve improved performance with lower complexity.