Energy Efficiency of Distributed Antenna Systems With Wireless Power Transfer

Abstract

In this paper, we study energy-efficient resource allocation in distributed antenna system (DAS) with wireless power transfer, where time-division multiple access (TDMA) is adopted for downlink multiuser information transmission. In particular, when a user is scheduled to receive information, other users harvest energy at the same time using the same radio-frequency (RF) signal. We consider two types of energy efficiency (EE) metrics: user-centric EE (UC-EE) and networkcentric EE (NC-EE). Our goal is to maximize the UC-EE and NC-EE, respectively, by optimizing the transmission time and power subject to the energy harvesting requirements of the users. For both UC-EE and NC-EE maximization problems, we transform the nonconvex problems into equivalently tractable problems by using suitable mathematical tools and then develop iterative algorithms to find the globally optimal solutions. Simulation results demonstrate the superiority of the proposed methods compared with the benchmark schemes. Index Terms-Distributed antenna systems (DAS), energy efficiency (EE), wireless power transfer, nonlinear programming. k Yuwen Huang received the B.S. degree from South

Slot‐hitting ratio‐based TDMA schedule for hybrid energy‐harvesting wireless sensor networks

“…Liu and Liu [24] considered TDMA and frequency-division multiple access resource allocation problems in a relay-assisted wireless-powered communication network, and they proposed an online optimal scheme for power and time allocation under TDMA. Huang et al [25] studied energy-efficient resource allocation in a distributed antenna system with wireless power transfer, where TDMA is adopted for downlink multiuser information transmission. Lv et al [26] investigated the uplink/downlink transmission problem by invoking the TDMA protocol, in which both the sum-throughput and fair-throughput are maximised by deciding the duration of each time slot and power.…”

Energy Efficiency in RF Energy Harvesting-Powered Distributed Antenna Systems for the Internet of Things

“…The optimal Lagrangian variables can be found by solving the problem in (20), where the BCD method [ 17 ] can be used, with one of and e being fixed to optimize the other. There are two cases of for a given e .…”

“…In [ 16 ], the system spectral efficiency of DAS with wireless power transmission (WPT) was evaluated. In [ 17 ], the authors maximized the network-centric EE and user-centric EE in DAS with WPT. In [ 18 ], the authors maximized the EE in DAS with SWIPT [ 19 , 20 , 21 ], where the power splitting (PS) receiver architecture was employed to fulfill EH and information decoding.…”

“…Therefore, this paper aims to maximize the system EE, to achieve the green communication system design. Although some existing works investigated the EE for DAS with RF EH, only the constraint of power control was considered, where the user’s information rate requirement was not involved; see, e.g., [ 17 , 18 ], while in our work, the system EE is maximized with the user’s minimal information rate requirement, which is much closer to the users’ demands. Different from the most similar existing works [ 22 , 23 ] where the linear EH model was used, in this work, the nonlinear EH model is adopted, as it was reported that the nonlinear EH one was obtained with real measurement data [ 26 , 27 ].…”

“…Although some existing works investigated the EE for DAS with RF EH, only the constraint of power control was considered, where the user’s information rate requirement was not involved; see, e.g., [ 17 , 18 ], while in our work, the system EE is maximized with the user’s minimal information rate requirement, which is much closer to the users’ demands.…”