Decentralized Beamforming for Location-Aware SWIPT in Coordinated Multi-Cell Networks

This paper focuses on the simultaneous wireless information and power transfer (SWIPT) in coordinated multi-cell networks. In particular, the considered system has a location-aware feature, i.e., the conventional coordinated multi-point (CoMP) information transmission is available to the cell-edge users; meanwhile, the emerging wireless power transmission is available to the cell-center users. Subject to the SINR constraints for information decoding at edge CoMP users and the received power constraints for energy storage at center users, our objective is to minimize the total transmit power of all coordinated beamformers. Although the celebrated semi-definite relaxation (SDR) technique can be applied to obtain a centralized optimal solution, we prefer to decompose the original problem and derive a decentralized closed-form solution to decrease the cost of inter- cell cooperation. With this low-complexity solution, some important insights are further presented on the benefit of the location-aware SWIPT setup and the potential user scheduling mechanism. Simulation results validate our derivation and show that the decentralized solution can asymptotically approach the centralized optimal solution.