Space-time block coded adaptive modulation aided OFDM

Space-time block codes provide substantial diversity advantages for multiple transmit antenna systems at a low decoding complexity. We investigate the achievable diversity advantages in the context of adaptive modulation aided turbo coded OFDM. The two-transmitter, one-receiver G₂ block space-time coded scheme using no channel coding or gradually increasing rate turbo coding strikes the best trade-off in terms of its overall performance and complexity. Adaptive OFDM performs impressively, when the extra complexity of space-time coding is not affordable, but no adaptive modulation is necessary in conjunction with the more complex multiple transmit and receive antenna associated scenario