Performance analysis comparison of transmit antenna selection with maximal ratio combining and orthogonal space time block codes in equicorrelated Rayleigh fading multiple input multiple output channels

In this study, bit error rate (BER) performance of multiple input multiple output (MIMO) systems employing transmit antenna selection with maximal ratio combining (TAS/MRC) and orthogonal space time block codes (OSTBC) is analysed and compared. Analysis has been done for several modulation schemes in equicorrelated Rayleigh fading channels. Novel infinite series expressions for BER of TAS/MRC are proposed in this work. The authors observe that the existing literature on performance analysis of TAS/MRC in correlated channels implicitly or explicitly assume no correlation on the transmitter side. In this work the authors overcome this shortcoming. An alternate closed-form expression for BER performance of OSTBC MIMO systems is derived. This closed-form expression is computationally efficient than existing expressions. Monte Carlo simulations were performed to validate the analytical results. It has been observed that TAS/MRC outperforms OSTBC in terms of BER performance in equicorrelated Rayleigh fading channel. As a case study, performance comparison of cognitive radio (CR) links employing OSTBC and TAS/MRC MIMO systems is investigated in order to show the usefulness of the present analytical study. Even though TAS is the optimum transmit antenna technique in terms of BER performance, OSTBC seems to be a promising alternative for more realistic scenarios in CR systems.