Cooperative STBC-OFDM Transmissions with Imperfect Synchronization in Time and Frequency

In this paper, we study the cooperative STBC-OFDM transmissions when the cooperative transmitters are not perfectly synchronized in time and carrier frequency. While OFDM can effectively resolve the limited delay asynchronism among the transmitters, the asynchronism in carrier frequency presents a major hurdle. Based on an approximate channel model, we analyze the performance of STBC-OFDM cooperative transmissions, compare them with non-cooperative ones, and propose a joint ICI mitigation and STBC decoding algorithm