ock-fading channels. Denote the transmitted signal vector from the transmitter as ${\mathbf{x}}\in {\mathbb{C}}^{N_t\times 1}$ with a transmit power constraint ${\mathrm{Tr}}\left(\mathbb{E}\{{\mathbf{x}}{\mathbf{x}}^H\}\right)=P$. The received signal at the receiver with reconfiguration state $\psi$ is given by $$\label{eq:yhxbasic}
  {\mathbf{y}}={\mathbf{H}}_{\psi}{\mathbf{x}}+{\mathbf{n}},$$ where ${\mathbf{H}}_{\psi}\in{\mathbb{C}}^{N_r\times N_t}$ denotes the channel matrix corresponding to the reconfiguration state $\psi$ and ${\mathbf{n}}\sim\mathcal{CN}(\mathbf{0};\sigma^2_n{\mathbf{I}}_{N_r})$ denotes the additive white Gaussian noise (AWGN) vector at the receive antennas. Without loss of generality, the noise variance is taken to be unity, i.e., $\sigma^2_n=1$. Note that ${\mathbf{H}}_{\psi}(i,j)$ represents the channel coefficient that contains the gain and phase information of the path between the $i$-th receive antenna and the $j$-th transmit antenna in the reconfiguration state $\psi$. We assume that the channel matrices for different reconfiguration states are independent [@Grau_08_AreMIMOcym; @Fazel09stsbcmmioyra; @Vakilian_15_SThmmra; @Vakilian_15_ThmmraAr], and have the same average channel power such that $\mathbb{E}\{\left\|{\mathbf{H}}_{1}\right\|^2_F\}=\cdots=\mathbb{E}\{\left\|{\mathbf{H}}_{\Psi}\right\|^2_F\}=N_rN_t$. It is worth mentioning that the assumption of orthogonal radiation characteristics is crucial for our analysis, since our results are based on the assumption of independent channel matrices associated with different reconfiguration states. If the radiation patterns are non-orthogonal, the channel matrices associated with different reconfiguration states would be correlated, and we would expect a relatively smaller throughput gain compared with the results in this paper.

We further assume that full channel state information (CSI) of all reconfiguration states is known at the receiver. The full CSI is not necessarily known at the transmitter. We assume that a limited feedbac