Asymptotic performance comparison between dominant eigenmode transmission and Tx/ selection-Rx/MRC for MIMO diversity gain over a Rayleigh fading channel

In this paper, asymptotic symbol error rates (ASERs), of dominant eigenmode transmission (DET) for MIMO (multiple inputs and multiple outputs) diversity gain with small diversity order (the product of the number of Tx antennas and the number of Rx antennas) and Tx/selection (SC)-Rx/MRC with an arbitrary diversity order over a Rayleigh fading channel are derived. The SNR gaps among DET, Tx/SC-Rx/MRC and that with a full diversity gain of the same order are also derived. It is found that for a 2 × 2 MIMO, DET performs better over Tx/SC-Rx/MRC by 1.18 dB and for 3 × 2 MIMO DET performs better by 1 dB. It is also found that a 3 × 2 Tx/SC-Rx/MRC outperforms a 2 × 3 Tx/SC-Rx/MRC by 1 dB. Simulation results match those in [1] and theoretic derivations in this paper.