Optimal resource allocation in OFDM decode-and-forward relay systems with SWIET

Huang, Gaofei; Tu, Wanqing; Tang, Dong

Abstract

Employing energy harvesting (EH) at a relay node with simultaneous wireless information and energy transfer (SWIET) is promising to prolong the lifetime of energy-constrained relay systems. In this paper, we investigate the optimal resource allocation in an orthogonal-frequency-division multiplexing (OFDM) decode-and-forward (DF) relay system that implements SWIET at the source-to-relay link in order to maximize the end-to-end achievable rate. We first propose an optimal energy-transfer power allocation (EPA) policy which can utilize the frequency diversity provided by OFDM modulation. We then validate that the ordered-SNR subcarrier pairing is globally optimum. To optimize EH time and information-transmission power allocation (IPA), we formulate the involved problem as a non-convex programming problem, and then transform it into a quasi-convex optimization problem. By solving this quasi-convex optimization problem with the bisection search method, we propose an algorithm which can jointly optimize the EH time and IPA. By analytical analysis, we validate that our proposed resource allocation scheme has much lower computational complexity than the peer studies in the literature. Finally, our simulations demonstrate the optimality of our proposed resource allocation scheme.

Citation

Huang, G., Tu, W., & Tang, D. (2015, August). Optimal resource allocation in OFDM decode-and-forward relay systems with SWIET. Presented at IEEE International Symposium on Personal Indoor and Mobile Radio Communications PIMRC, Hong Kong

• Presentation Conference Type: Conference Paper (published)
• Conference Name: IEEE International Symposium on Personal Indoor and Mobile Radio Communications PIMRC
• Start Date: Aug 30, 2015
• End Date: Sep 2, 2015
• Online Publication Date: Dec 3, 2015
• Publication Date: Dec 1, 2015
• Deposit Date: Jun 7, 2025
• Peer Reviewed: Peer Reviewed
• Volume: 2015-December
• Pages: 634-639
• Book Title: 2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC)
• DOI: https://doi.org/10.1109/PIMRC.2015.7343376
• Public URL: https://durham-repository.worktribe.com/output/4092144