Multi-Cell User-Scheduling and Random Beamforming Strategies for Downlink Wireless Communications

We consider random beamforming and user scheduling strategies in a multi-cell environment for downlink wireless communications. Our focus is on using combined scheduling and beamforming to mitigate performance losses due to inter-cell interference. Of interest are strategies requiring minimal intra-cell and inter-cell system information exchange. Indeed the acquisition and inter-cell exchange of such information can be significant overheads in a practical deployment. Random beamforming requires substantially less channel state information than linear zero forcing strategies to schedule transmissions. It is therefore of practical interest despite some limitations in controlling intra-cell interference. We consider how one can use a minimal exchange of information, in a multi-cell multistep pattern of exchanges, to improve the overall performance of random beamforming in a multi-cell environment.