Optimal Power and Time Allocation for WPCNs with Piece-wise Linear EH Model

TL;DR

This paper introduces an optimal resource allocation strategy for wireless powered communication networks considering a realistic piece-wise linear energy harvesting model, enhancing sum rate performance by accounting for non-linearities.

Contribution

It presents a novel transmission protocol that incorporates the non-linear energy harvesting model and derives optimal power and time allocations for improved network efficiency.

Findings

Non-linear EH model significantly affects optimal resource allocation.

Saturation effects become prominent at high transmit powers.

Proposed method improves sum rate in WPCNs.

Abstract

We propose a novel transmission protocol for harvest-then-transmit wireless powered communication networks, which takes into account the non-linearity of the energy harvesting (EH) process at the EH users and maximizes the sum rate in the uplink. We assume a piece-wise linear energy harvesting model and provide expressions for the optimal transmit power of the base station (BS), the duration of the EH phase, and the duration of the uplink information transmission phases of the users. The obtained solution provides insight regarding the significance of the non-linear EH model on the optimal resource allocation. Simulations unveil the growing impact of the saturation effect, which occurs for high received radio frequency powers, as the average and the maximum instantaneous transmit powers of the BS increase.