Outage and throughput analysis of power-beacon assisted nonlinear energy harvesting NOMA multi-user relay system over Nakagami- m fading channels

Tran Manh Hoang; Ba Cao Nguyen; Tran Thanh Trung; Le The Dung

doi:10.1016/j.heliyon.2020.e05440

Outage and throughput analysis of power-beacon assisted nonlinear energy harvesting NOMA multi-user relay system over Nakagami- m fading channels

Heliyon. 2020 Nov 10;6(11):e05440. doi: 10.1016/j.heliyon.2020.e05440. eCollection 2020 Nov.

Authors

Tran Manh Hoang¹, Ba Cao Nguyen¹, Tran Thanh Trung¹, Le The Dung^{2

3}

Affiliations

¹ Telecommunications University, Khanh Hoa Province, Viet Nam.
² Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City, Viet Nam.
³ Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City, Viet Nam.

Abstract

This paper considers a non-orthogonal multiple access (NOMA) multi-user relay system where both source and relay harvest the energy from a power beacon (PB) equipped with multiple antennas and use this harvested energy to transmit signals to several users. Realistic nonlinear energy harvesting models are applied, and time switching protocols are adopted at source and relay. We successfully derive the exact closed-form expressions of the outage probability and throughput of the system over Nakagami-m fading channels. Then, we use Monte-Carlo simulations to validate the correctness of these derived mathematical expressions. Numerical results show that a higher saturated power threshold of the nonlinear energy harvester results in lower outage probability and higher throughput. Moreover, the optimal time switching ratio that maximizes the throughput is smaller than the optimal time switching ratio that minimizes the outage probability.

Keywords: Algebra; Communication system; Electrical engineering; Non-orthogonal multiple access; Nonlinear energy harvesting; Outage probability; Power beacon; Probability theory; Signal processing; Statistics; Successive interference cancellation; Throughput; Wireless network.