Statistical characterization of the time-varying orthogonalized MIMO systems over non-isotropic Rayleigh fading channels

In this paper, we investigate the performances of time-varying multiple-input-multiple-output (MIMO) systems. In particular, we consider statistical properties of the output signal-to-noise ratio (SNR) for two classes of MIMO techniques - multichannel beamforming (MB) and orthogonal space-time block codes (OSTBC). The closed-form expressions for the probability density function (PDF) and the level crossing rate (LCR) of the output SNR are obtained for the arbitrary channel matrix dimensions for the case of Rayleigh propagation with non-isotropic scattering. Using the derived expressions, we find the parameters for a corresponding finite state Markov channel model that is used to determine the throughput and the residual packet error rate in time-varying MIMO system with hybrid automatic repeat-request (HARQ) procedures. Numerical simulations are provided to endorse our theoretical results.