Closed-Form Capacity Expression for Transmit Antenna Selection Systems with Correlated Fading Channels

In this paper, the exact closed-form capacity expression for a hybrid selection/MIMO (H-S/MIMO) system in the spatial correlated Rayleigh fading channels is investigated. There are two assumptions in this work. One is that the antenna selection at the transmitter is based on the criterion that maximizes the received signal power and only one transmit antenna is chosen for a transmission interval. The other is that the spatial correlation is present at both ends of wireless communications link. Based on the two assumptions, the characteristic function (CF) method is used to analyze the capacity of the H-S/MIMO systems. Then a closed-form capacity expression is achieved in this paper. A special system, having two transmit-antennas and two/three receive-antennas, is taken for example to validate our theoretic analysis. Results show that the analytical results are very close to the simulations.