Joint Optimization of Beamforming and Base Station Clustering Based on Leakage Rate

Abstract

It has been proved that jointly designing the base station (BS) clusters and the beamformers performs better than designing separately in the heterogeneous wireless networks. In this letter, to make a tradeoff between the improvement of sum rate and the interference suppression, the joint optimization problem is formulated based on a new measurement named leakage rate and a per-user iterative algorithm is proposed to solve the objective problem. First, a leakage channel model using the leakage signal as the additive interference is defined. And a sum leakage rate maximization problem over the leakage channel is formulated with the limitation of BS transmit power and the sparse structure of beamformers. Second, we design a novel per-user iterative algorithm, which only iterates within each single cell. Compared with the capacity maximization method, simulation results indicate that our proposed algorithm can achieve the better performance of interference suppression with a small fraction of capacity loss.