Cooperative power allocation with partial channel information in multi-cell multi-user dual-hop MIMO relay systems

This paper considers cooperative power allocation with the use of partial channel state information (CSI) in a multi-user dual-hop relay system with multiple antennas. The end-to-end capacity can be improved by dynamically allocating the transmit power of the base station and relay according to co-channel interference caused by the adjacent relays. The proposed scheme allocates the transmit power in association with the eigenvalues and angle difference between the eigenvectors of transmit correlation matrices of the desired and interference channel. It is shown by means of upper-bound analysis that the end-to-end capacity of the proposed scheme can be maximized in highly correlated channel environments when the principal eigenvectors of transmit correlation matrices of the desired and interference channel are orthogonal to each other. It is also shown that the proposed scheme is robust to the channel estimation error. Finally, the performance of the proposed scheme is verified by the computer simulation. Copyright (C) 2010 John Wiley & Sons, Ltd.