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Transmit Antenna Selection for Hybrid Space-Time Block Code with Decision-Feedback Detector
Joohan Kim,Hyounkuk Kim,Hyuncheol Park IEEE 2007 2007 IEEE Vehicular Technology Conference Vol.2007 No.9
<P>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.</P>
High-Throughput Low-Complexity Link Adaptation for MIMO BIC-OFDM Systems
Cheolkyu Shin,Hyounkuk Kim,Kyeong Jin Kim,Hyuncheol Park IEEE 2011 IEEE TRANSACTIONS ON COMMUNICATIONS Vol.59 No.4
<P>This paper introduces a new link adaptation (LA) approach called the adaptive modulation, coding, and spatial mode (AMCS) scheme for multiple-input multiple-output bit-interleaved coded orthogonal frequency division multiplexing (MIMO BIC-OFDM) systems. The AMCS technique can provide both minimal performance degradation and significant throughput gain by controlling the spatial streams. With this technique, we can derive a simple and accurate closed-form expression of an instantaneous bit error rate (I-BER). Based on the I-BER, the proposed AMCS scheme chooses an appropriate modulation, coding, and spatial mode (MCS) type that improves the system performance while satisfying the quality of service (QoS) requirement. A simplified MCS type search method is also proposed, which allows the receiver to effectively select a MCS type and then send it back to the transmitter by using only a small amount of information bits. The simulation results confirm the superiority of the proposed AMCS approach over conventional LA schemes in trading high-throughput for reduced complexity.</P>