Orthogonal delay diversity realization and cyclic group codes for MIMO-OFDM

A delayed space-frequency cyclic group code is proposed in this paper, which applies a new bandwidth and power-efficient space-frequency processing on the orthogonal-frequency- division-multiplexing (OFDM) system. The delayed orthogonality with respect to frequency tones among different transmitter antennas guarantees to exploit the full spatial and frequency diversity of the frequency-selective multi-input multi-output (MIMO) channel. In contrast with the schemes which combine the single-antenna error correcting code with delayed transmitter diversity in multi-antenna OFDM systems, this space-frequency code has a robust performance in flat-fading channel. Without a tradeoff of the diversity gain, the proposed code can be easily expanded to achieve high data rate and generalized to more than two transmit antennas.