Joint Power Allocation and Receive Filtering for Uplink MU-MIMO Multi-Carrier Transmission

We consider the optimization of transmit powers and linear receivers for transmission from multiple single-antenna terminals to a central receiver equipped with multiple antennas and aim to minimize the overall transmission power with respect to given targets on the signal-to-interference-and-noise-ratio. This design goal has been previously investigated with respect to frequency flat channels, which applies for instance to transmission on individual subcarriers of a multi-carrier system. We extend previous algorithmic solutions, which solve the underlying optimization problem with one transmit power constraint per user on each frequency flat channel to the case where one user's power can be distributed over multiple frequency flat channels. We then apply the concept to multi-carrier transmissions where, due to practical constraints on signalling overhead and complexity, transmit powers can only be optimized for clusters of subcarriers. By means of simulations we compare several approaches to define adequate channel state information per cluster of subcarriers for the computation of transmit powers.