Performance of delay diversity with subcarrier-based signal phase rotation in OFDM system

This paper investigates the performance of delay diversity with subcarrier-based signal phase rotation in an OFDM system. Delay diversity achieves transmit diversity with channel coding by intentionally ingenerating paths which have different delays at a transmitter side. However, the correlation between subcarriers is not always low. The proposed scheme which combines the delay diversity and the phase rotation of the transmit signal offers diversity gain by reducing the correlation between the specific combination of the subcarriers. It is shown through computer simulation that the proposed scheme improves the BER performance by about 2 dB with a repetition code.