AbstractThree design requirements of space‐time block code, full diversity order, full data rate and orthogonality, cannot be achieved simultaneously when the number of transmit antenna is more than two. In this paper, we propose a transmit diversity scheme—circular shifted transmit diversity (CSTD). CSTD can always achieve the full data rate and has very low decoding complexity. Through the performance analysis and simulation comparison in the case of same spectrum efficiency between CSTD and other well‐known proposed schemes, it can be proved that CSTD always significantly outperforms the other transmit diversity schemes with full data rate. Additionally, compared with the transmit diversity schemes with full diversity order, CSTD has lower complexity and approximately the same performance when channel coding is concatenated. Copyright © 2004 John Wiley & Sons, Ltd.