Energy-efficient resource allocation in CoMP-SWIPT heterogeneous networks

In this paper, a fundamental study of energy efficiency (EE) optimization for coordinated multi-point (CoMP)-simultaneous wireless information and power transfer (SWIPT) heterogeneous networks (HetNets) is provided. We aim to optimize the EE whilst satisfying certain quality-of-service (QoS) requirements in regard to transmission rate and energy harvesting at both the macro-cell and small-cells. The corresponding joint beamforming and power allocation in the presence of intra- and inter-cell interference constitutes a EE maximization problem that is non-convex, and hence very challenging to solve. In order to solve this problem, we propose to separate the beamforming design and power allocation processes. In particular, different from the the conventional linear zero-forcing beamforming where the beneficial interference is removed, a partial zero-forcing approach has been proposed by differentiating the energy harvesting users and information decoding users in order to improve the EE. Our findings show that the EE can be significantly improved through the integration of CoMP-SWIPT in HetNets.