Transmit Antenna Selection for Hybrid Space-Time Block Code with Decision-Feedback Detector

High spectral efficiency and the reliability can be achieved by multiple transmit/receive antennas. As a such system, double space-time transmit diversity (DSTTD) is introduced. Furthermore, an antenna shuffling using partial channel feedback can additionally improve performance of the DSTTD system. However, the multiple antennas and the amount of feedback overhead are serious burden to system in terms of complexity and cost. In this paper, we consider hybrid space time code (STBC) with three transmit antennas. By deriving the error performance of hybrid STBC with zero-forcing decision feedback (ZF-DF) detector, it is demonstrated that hybrid STBC has almost the same performance of the DSTTD system. Then, we apply an antenna subset selection scheme to hybrid STBC. Though this scheme needs the fewer number of transmit antennas and the smaller amount of feedback overhead than those of antenna shuffling, it can provide comparable error performance of antenna shuffling. Especially, on selecting transmit antennas, we propose an efficient transmit antenna selection rule for ZF-DF detector.