Uneven Power Amplifier Shuffling for Space-Time Line Code Systems

In this paper, a novel power amplifier (PA) shuffling method is proposed for a space-time line code (STLC) system with uneven PA gains. The proposed method is composed of pre-shuffling and post-shuffling, which represent the assignment of STLC symbols to PAs and the allocation of PAs to transmit antennas, respectively. Through these shuffling procedures, the proposed scheme matches the larger gain PA to the larger effective channel gain with STLC in order to maximize the STLC decoding signal-to-noise ratio (SNR). A theoretical analysis provides a formula to compute the decoding SNR, and it is shown through numerical simulations that the proposed PA shuffling method can significantly improve the performance of conventional STLC systems, regardless of the channel state information uncertainty, especially when the number of transmit antennas is large.