Multiple-input multiple-output (MIMO) repeater systems have been discussed in several published papers. When a repeater has only one antenna element, the propagation environment is called keyhole. In this kind of scenario the achievable channel capacity and link quality are decreased. Another limit is when the number of the antenna elements of a repeater is larger than that of a MIMO transceiver, the channel capacity cannot be increased. In this paper, in order to obtain an upper bound of the channel capacity, we express a propagation process of the distributed MIMO repeater system with amplify-and-forward method by the numerical formular, and optimize the position of each repeater.