NOMA Throughput and Energy Efficiency in Energy Harvesting Enabled Networks

Abstract

Wireless power transfer via radio-frequency (RF) radiation is regarded as a potential solution to energize energy-constrained users, who are deployed close to the base stations (near-by users). However, energy transfer requires much more transmit power than normal information transfer, which makes it very challenging to provide the quality of service in terms of throughput for all near-by users and cell-edge users. Thus, it is of practical interest to employ non-orthogonal multiple access (NOMA) to improve the throughput of all network users, while fulfilling the energy harvesting requirements of the near-by users. To realize both energy harvesting and information decoding, we consider a transmit time-switching (transmit-TS) protocol. We formulate two important beamfoming problems of users' max-min throughput optimization and energy efficiency maximization under power constraint and energy harvesting thresholds at the nearly-located users. For these problems, the optimization objective and energy harvesting are non-convex in beamforming vectors. Thus, we develop efficient path-following algorithms to solve them. In addition, we also consider conventional power splitting (PS)-based energy harvesting receiver. Our numerical results confirm that the proposed transmit-TS based algorithms clearly outperform PS-based algorithms in terms of both, throughput and energy efficiency.Index Terms-Wireless power transfer, energy harvesting, non-orthogonal multiple access (NOMA), nonconvex optimization, throughput, energy efficiency, quality-of-service (QoS).

Joint Design of Reconfigurable Intelligent Surfaces and Transmit Beamforming Under Proper and Improper Gaussian Signaling

“…The following results of [46] are used The following inequalities for matrices of dimension 2 × 2 hold true [47], [48]:…”

Cooperative NOMA system with incremental relaying and energy harvesting: Performance analysis and optimization

“…The performance of conventional CR‐NOMA systems has been extensively analyzed in the literature (eg, References 9‐12 and references therein). Recently, the performance of EH based conventional CR‐NOMA systems (ie, CR‐EH‐NOMA) has also been widely investigated; see References 13‐32 and references therein. In Reference 13, the authors have analyzed the outage and throughput performance of CR‐NOMA systems integrated with EH, where the locations of the users have been modeled using stochastic geometric based approach.…”

“…In Reference 27, the authors have independently analyzed outage performance of EH enabled CR‐NOMA system with HD relay. The energy efficiency optimization for SWIPT based CR‐NOMA systems has been considered by various authors in References 28‐32.…”

Transmitter-Side Wireless Information- and Power-Transfer in Massive MIMO Systems

“…For a modest number of antennas at the BS, the transmit-TS approach outperformed both the receive-TS and the PS approaches [12], [15]. However, its extension to m-MIMO systems has hitherto not been considered due to the computational complexity of the corresponding optimization problem, which became large-scale nonconvex.…”