Matched Rotation Precoding: A New Paradigm in Space-Frequency Coding

This paper proposes an efficient rate one space-frequency block code (SFBC) for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems. The proposed SFBC incorporates concept of matched rotation precoding (MRP) to achieve full transmit diversity and optimal system performance for arbitrary number of transmit antennas, subcarrier interval and subcarrier grouping. The MRP exploits the inherent rotation property of SFBC and has relaxed restrictions on subcarrier interval and subcarrier grouping, making it ideal for adaptive/time varying systems. The lowerbound of the coding gain for MRP is derived and shown that it is useful when designing a SFBC for practical scenarios, e.g. when transmitters have only partial knowledge of power delay profile or when the power delay profile has only a few dominant delayed paths. Simulation results show that the MRP can achieve a similar or better performance than existing SFBCs.