On the Channel Capacity of MIMO Systems Under Correlated Rayleigh Fading

Abstract

In order to study the impacts of channel model parameters on the channel capacity of a multiple input multiple output (MIMO) system, a novel method is proposed to explore the channel capacity under Rayleigh flat fading with correlated transmit and correlated receive antennas. The optimal transmitting direction which can achieve maximum channel capacity is derived in detail using random matrices theory. At high SNR, the closed-form expression for the channel capacity of MIMO system is given by using the properties of Wishart distribution. Computer simulation results show that the channel capacity is maximized when the antenna spacing increases to a certain point. At high SNR, the estimation of channel capacity is close to its true value. And when the same array configuration is adopted both at the transmitter and the receiver, the UCA yields higher channel capacity than ULA.