Beamforming Design for Uplink MU-MIMO Wireless Network Virtualization

We provide wireless network virtualization (WNV) for multiple service providers (SPs) that are assumed to virtually serve multi-antenna users via a base station (BS) with multiple antennas. The virtualization of this multi-user multiple-input multiple-output (MU-MIMO) system is managed by an infrastructure provider (InP) that owns the communication equipment. By exploiting the antennas at both the BS and the user devices, we jointly design the uplink receive beamforming at the BS and the transmit beamforming at the user devices, achieving service isolation at the physical layer. This WNV is formulated as a non-convex optimization problem in the transmit and receive beamforming vectors. We derive separately optimal closed-form and semi-closed form solutions for the beamforming vectors, and use these solutions in alternating iterations to solve the original problem. Our simulation results show that the proposed solution enables effective network virtualization, to support the independent operation of multiple SPs, while retaining efficiency no less than non-virtualized operation, and it substantially outperforms traditional WNV based on strict resource separation.