In this paper we show the effect of partial channel
knowledge at the receiver which causes estimation error of the channel at the receiver and the spatial correlation on MIMO Relay wireless communication systems. We assume that the transmitter has perfect knowledge of statistical parameters of the channel such as covariance or mean. We show how the topology of the equipment can upgrade or degrade the channel and we generalize a relaying MIMO scenario. We mathematically approach the gain of a system that uses relaying antennas. We assume a Zero Mean Circular Symmetric Complex Gaussian(ZMCSCG) channel elements and ZMCSCG noise elements. As we examine spatial correlation at the transmitter only, we assume that the elements of the rows of the channel matrix of the first hop are correlated. Partial CSI at the receiver causes errors at the estimation of the channel at the receiver which results the
channel capacity to degrade and to saturate at certain levels of SNR. Numerical simulations are conducted in order to support the theoretical results used in this pape