Multi-cell coordinated beamforming and power allocation with large scale MIMO

We consider the downlink of a multi-cell network where neighboring base stations with large scale antennas share the spectrum and collaborate with each other to improve the overall network performance. This paper utilizes the zero-forcing (ZF) transmit beamformer, which has been proven as the simplest and optimal form for high SNR in large scale antennas system. The objective of the coordination is to minimize the total transmit power and meanwhile satisfy the quality-of-service (QoS) requirements with the minimum total transmit power. Based on the properties of large scale MIMO and sparse approximate inverse preconditioners (AINV), we propose the approximately optimal algorithm and AINV based algorithm. Numerical simulations demonstrate the performance of proposed strategies.