Rate-Maximizing Adaptation in Multiantenna OFDM Systems With Space-Time-Frequency Coding

In this paper, we first propose a space-time-frequency (STF) coding method for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) transmission over frequency-selective fading channels and then, based on channel mean feedback model, we develop an adaptive MIMO-OFDM transmitter by applying an adaptive energy and bit loading scheme across OFDM subcarriers. Under the constraints of fixed transmit-energy and prescribed error performance, our objective is to maximize the transmission rate. Simulation results are presented which confirm the performance of our proposed system and show that under certain circumstances, the transmission rate improves considerably as compared with competing schemes.