Secrecy Beamforming for SWIPT MISO Heterogeneous Cellular Networks

TL;DR

This paper develops a beamforming strategy for secure wireless information and power transfer in a heterogeneous cellular network, ensuring confidentiality and energy harvesting while managing interference.

Contribution

It introduces a novel beamforming design for secure SWIPT in Femtocell-Macrocell networks using semidefinite relaxation and convex approximation techniques.

Findings

Proposed beamforming achieves higher secrecy rates.

Effectively manages interference to macrocell users.

Enhances energy harvesting efficiency.

Abstract

In this paper, we consider the secure transmission design for a multiple-input single-output Femtocell overlaid with a Macrocell in co-channel deployment. The Femtocell base station sends confidential messages to information receiving Femtocell users (FUs) and energy signals to energy receiving (ER) FUs while limiting the interference to Macrocell users (MUs). The ER FUs have the potential to wiretap the confidential messages. By taking fairness into account, we propose a sum logarithmic secrecy rate maximization beamforming design problem under the interference constraints for MUs and energy harvesting (EH) constraints for ER FUs. The formulated design problem is nontrivial to solve due to the nonconvexity which lies in the objective and the constraints. To tackle the design problem, a semidefinite relaxation and successive convex approximation based algorithm is proposed. Simulation results demonstrate the effectiveness of the proposed beamforming design.