Power Allocation for Beamforming Relay Networks under Channel Uncertainties

Under uncertain channel conditions, local and global power control factors for amplify-and-forward relay processing and source-destination beamforming are jointly and iteratively designed based on a minimum mean-square-error (MMSE) criterion. The influence of imperfect channel information on system performance is examined by computer simulation. As a result, it is verified that the proposed power control methods can relieve the performance degradation arising from channel uncertainties.