Interference Coordination Based on Statistical CSI in Multi-User MISO Cellular System

This paper considers an interference coordination with the use of statistical channel state information (CSI) (e. g., transmit correlation) to mitigate other-cell interference (OCI) in a multi-user multi-input single-output (MISO) cellular system. To this end, we first show that the OCI can be characterized in terms of eigenvalues and angle difference between eigenvectors of the transmit correlation matrices of the desired and OCI channel. Then, a coordinated user scheduling strategy is designed with the use of statistical beamforming to minimize the OCI in an average sense. Analytic and numerical results show that the proposed scheme can maximize the achievable sum-rate when the principal eigenvectors of the transmit correlation matrices of the desired and OCI channel are orthogonal to each other, yielding a sum-rate performance comparable to that of minimum mean-square error-based coordinated beamforming (MMSE-CBF) with the use of instantaneous CSI.