SWIPT-Enabled Multiple Access Channel: Effects of Decoding Cost and Non-linear EH Model

TL;DR

This paper investigates the impact of decoding costs and non-linear energy harvesting models on the performance of power splitting-based SWIPT in multiple access channels, providing optimal strategies and analyzing cooperation benefits.

Contribution

It introduces a comprehensive analysis of PS-SWIPT MAC considering practical decoding costs and non-linear EH, deriving optimal power and splitting strategies for different scenarios.

Findings

Successive interference cancellation outperforms simultaneous decoding under certain conditions.

User cooperation can significantly enhance system performance.

Decoding cost functions and non-linear EH models critically influence optimal system parameters.

Abstract

We studied power splitting-based simultaneous wireless information and power transfer (PS-SWIPT) in multiple access channels (MAC), considering the decoding cost and non-linear energy harvesting (EH) constraints at the receiving nodes to study practical limitations of an EH communication system. Under these restrictions, we formulated and analyzed the achievable rate and maximum departure regions in two well-studied scenarios, i.e., a classical PS-SWIPT MAC and a PS-SWIPT MAC with user cooperation. In the classical PS-SWIPT MAC setting, closed-form expressions for the optimal values of the PS factors are derived for two fundamental decoding schemes: simultaneous decoding and successive interference cancellation. In the PS-SWIPT MAC with user cooperation, the joint optimal power allocation for users as well as the optimal PS factor are derived. This reveals that one decoding scheme outperforms the other in the classical PS-SWIPT MAC, depending on the function type of the decoding cost. Finally, it is shown that the cooperation between users can potentially boost the performance of a PS-SWIPT MAC under decoding cost and non-linear EH constraints. Moreover, effects of the decoding cost functions, non-linear EH model and channel quality between the users are studied, and performance characteristics of the system are discussed.