Error Rate of MIMO OSTBC Systems over Mixed Nakagami- $m$ / Rice Fading Channels

We study the performance of multiple-input multiple-output orthogonal space-time block coded systems over mixed Nakagami-
m
/Rice fading channels. Novel closed-form expression for the exact average bit error rate (ABER) of Gray coded rectangular quadrature amplitude modulation is obtained. This expression include already published formulae for other fading channels as special cases. We further derive simple expression for the asymptotic ABER, the diversity order, and the coding gain, which give useful insights for the system performance at high signal-to-noise ratio values. Extensive numerical and computer simulation results are presented to validate the accuracy of the proposed analysis.