Capacity studies of spatially correlated MIMO Rice channels

In this paper, we have studied the statistical properties of the capacity of spatially correlated multiple-input multiple-output (MIMO) Rice channels. We have derived an exact closed-form expression for the probability density function (PDF) and an exact expression for the cumulative distribution function (CDF) of the channel capacity for single-input multiple-output (SIMO) and multiple-input single-output (MISO) systems. Furthermore, an accurate closed-form expression has been derived for the level-crossing rate (LCR) and an accurate expression has been obtained for the average duration of fades (ADF) of the SIMO and MISO channel capacities. For the MIMO case, we have investigated the PDF, CDF, LCR, and ADF based on a lower bound on the channel capacity. The results are studied for a different number of transmit and receive antennas, but the proposed method can also be used to investigate the influence of some key parameters on the channel capacity, such as the antenna spacings of the transmitter and the receiver antenna arrays, and the amplitude of the time-invariant line-of-sight (LOS) component. The analytical expressions are valid for the well-known Kronecker model and an LOS component orthogonal to the direction of motion of the receiver. The correctness of the derived expressions is confirmed by simulations.