On the Capacity of Weibull Fading MIMO Channels under Different Adaptive Transmission Techniques

Space-time block codes (STBCs) are known to orthogonalize the multiple-input multiple-out (MIMO) wireless channels. In this paper, we study the capacity of STBCs over Weibull MIMO channels under three adaptive transmission techniques: optimal power and rate adaptation (orpa), optimal rate adaptation with constant transmit power (ora) and channel inversion with fixed rate. In particular, we obtain closed-form expressions for channel capacity of orthogonalized Weibull MIMO channels under these adaptive transmission techniques. This capacity provides an upper bound on spectral efficiency using these techniques and avoids Monte-Carlo simulations. Moreover, we also examine the effects of the fading severity on the concerned quantities. The figures show that our theoretical results of channel capacity line up exactly with the simulations.