Improved space-time coding for multiple-input and multiple-output orthogona
l frequency division multiplexing is studied for wireless systems using QPS
K modulation for four transmit and four receive antennas. A 256-state code
is shown to perform within 3 dB of outage capacity (and within 2 dB with pe
rfect channel estimation), which is better than any other published result
without using iterative decoding.