Joint design of beamforming and time switching/power splitting for wireless-powered multi-antenna dual-relay network

Abstract In this paper, we consider a wireless-powered dual-relay network consisting of one multi-antenna source, two single-antenna energy-constrained relays and one single-antenna destination without direct source to destination link. In order to establish the communication flow, the energy-constrained relays harvest energy from the radio frequency transmitted by the source firstly, then exploit the harvested energy to forward the source information to the destination based on distributed space time coding (DSTC). Under this network architecture, three decode-and-forward (DF) technique-based relaying protocols, i.e., time switching-based relaying (TSR) protocol, power splitting-based relaying (PSR) protocol, and hybrid relaying (HR) protocol, are considered to drive the energy transfer and information transmission. To maximize the network throughput, the joint design for the optimal energy and information beamforming vectors employed at the source, the optimal time switching, and power splitting ratios under these three protocols are investigated and solved efficiently by employing simple sequential optimization approach or alternating optimization approach. Simulations are conducted to show the superior performance achieved by our proposed scheme. Moreover, we find that the TSR protocol outperforms the PSR protocol in the low signal-to-noise ratio (SNR) region, while the latter outperforms the former in the high SNR region. And the HR protocol achieves the best performance in any SNR region. At the same time, the effect of the relays’ locations on the throughput performance of these three protocols is also investigated.

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Dynamic Power Splitting Strategy for SWIPT Based Two-Way Multiplicative AF Relay Networks with Nonlinear Energy Harvesting Model

Wireless Communications and Mobile Computing ◽

10.1155/2018/1802063 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Tianci Wang ◽

Guangyue Lu ◽

Yinghui Ye ◽

Yuan Ren

Keyword(s):

Energy Harvesting ◽

Iterative Method ◽

Relay Network ◽

Power Splitting ◽

Amplify And Forward ◽

Channel State ◽

Dynamic Power ◽

Energy Constrained ◽

Af Relay ◽

Nonlinear Energy

This paper investigates an energy-constrained two-way multiplicative amplify-and-forward (AF) relay network, where a practical nonlinear energy harvesting (NLEH) model is equipped at the relay to realize simultaneous wireless information and power transfer (SWIPT). We focus on the design of dynamic power splitting (DPS) strategy, in which the PS ratio is able to adjust itself according to the instantaneous channel state information (CSI). Specifically, we first formulate an optimization problem to maximize the outage throughput, subject to the NLEH. Since this formulated problem is nonconvex and difficult to solve, we further transfer it into an equivalent problem and develop a Dinkelbach iterative method to obtain the corresponding solution. Numerical results are given to verify the quick convergence of the proposed iterative method and show the superior outage throughput of the designed DPS strategy by comparing with two peer strategies designed for the linear energy harvesting (LEH) model.

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Dynamic Wireless Energy Harvesting and Optimal Distribution in Multipair DF Relay Network with Nonlinear Energy Conversion Model

Wireless Communications and Mobile Computing ◽

10.1155/2018/7638215 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 2

Author(s):

Syed Tariq Shah ◽

Daniel B. da Costa ◽

Kae Won Choi ◽

Min Young Chung

Keyword(s):

Energy Harvesting ◽

Energy Conversion ◽

Relay Network ◽

Power Splitting ◽

Decode And Forward ◽

Conversion Model ◽

Transmission Modes ◽

Energy Constrained ◽

Wireless Energy Harvesting ◽

Nonlinear Energy

Wireless energy harvesting has emerged as an efficient solution to prolong the lifetime of wireless networks composed of energy-constrained nodes. In this paper, we consider a multipoint-to-multipoint relay network, where multiple source nodes communicate with their respective destination nodes via intermediate energy-constrained decode-and-forward (DF) relay. The performance of two different transmission modes, namely, delay tolerant and delay nontolerant, is studied. Based on power-splitting relaying protocol (PSR), optimal energy harvesting and distribution schemes for both transmission modes are provided. In addition, for more realistic and practical analysis, we consider a nonlinear energy conversion model for energy harvesting at the relay node. Our numerical results provide useful insights into different system parameters of a nonlinear energy harvesting-based multipair DF relay network.

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Optimal time switching and power splitting in SWIPT

2016 19th International Multi-Topic Conference (INMIC) ◽

10.1109/inmic.2016.7840157 ◽

2016 ◽

Cited By ~ 2

Author(s):

Furqan Jameel ◽

Asif Ali ◽

Rasheed Khan

Keyword(s):

Optimal Time ◽

Power Splitting ◽

Time Switching

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Time and Power Allocation for Energy Efficiency Maximization in Wireless-Powered Full-Duplex Relay Systems

Future Internet ◽

10.3390/fi11100205 ◽

2019 ◽

Vol 11 (10) ◽

pp. 205

Author(s):

Song ◽

Ni ◽

Han ◽

Qin ◽

Dong

Keyword(s):

Energy Efficiency ◽

Energy Harvesting ◽

Power Allocation ◽

Full Duplex ◽

Optimal Time ◽

Wireless Power ◽

Time Switching ◽

Relay Systems ◽

Single Antenna ◽

Wireless Power Supply

In this paper, we propose an optimal time and power allocation scheme in a wireless power supply full-duplex (FD) relay system, where we consider the number of relay antennas in the energy harvesting stage. At the same time, the energy efficiency optimization problem of the system is structured, where optimization issues related to time allocation factors and power allocation are established. For the FD dual-antenna and the FD single-antenna energy harvesting system, energy efficiency function is proven to be a concave function over the time-switch factor, and the optimal time-switching factor is theoretically obtained using the Lambert function. Then, according to the given value range of the optimal time switching factor, the optimal power distribution scheme is obtained by analyzing the derivative function of the system energy efficiency and using the properties of the Lambert function. The time-switching factor and transmission power are optimally selected at the wireless power supply FD relay. Results reveal that the performance of energy efficiency of the dual-antenna energy harvesting at the FD relay outperforms that of the single-antenna. Moreover, our results demonstrate that FD relay systems always substantially boost the energy efficiency compared with half-duplex (HD) relay systems.

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Hybrid Active-and-Passive Relaying model for SWIPT-enabled 6G-IoT Greencom Networks

10.36227/techrxiv.12893750 ◽

2020 ◽

Author(s):

Sumit Gautam ◽

Shree Krishna Sharma ◽

Dinh-Hieu Tran ◽

Symeon Chatzinotas ◽

Bjorn Ottersten

Keyword(s):

Individual Performance ◽

Superior Performance ◽

Power Splitting ◽

Hybrid Scheme ◽

Efficient Manner ◽

Time Switching ◽

Weighted Utility ◽

Time Period ◽

Massive Number ◽

Iot Devices

<div>In order to support a massive number of resource-constrained Internet of Things (IoT) devices and machine-type devices, it is crucial to design future beyond 5G/6G wireless networks in an energy-efficient manner while incorporating the network extension methodologies. To this end, this letter proposes a novel two-hop hybrid active-and-passive relaying scheme to facilitate simultaneous wireless information and power transfer (SWIPT) considering both the Time-Switching (TS) and Power-Splitting (PS) receiver architectures, while dynamically modelling the involved dual-hop time-period (TP) metric. An optimization problem is formulated for the joint optimization of throughput, harvested energy, and transmit power of a SWIPT-enabled system</div><div>with the proposed hybrid scheme, and is solved using a nonlinear optimizer. Our numerical results in terms of weighted utility function show the superior performance of proposed hybrid scheme over passive repeater-only and active relay-only schemes, while also depicting their individual performance benefits over the corresponding benchmark SWIPT systems with the fixed-TP.</div>

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Hybrid Backscatter and Relaying Scheme for 6G Greencom IoT Networks with SWIPT

10.36227/techrxiv.12893750.v1 ◽

2020 ◽

Author(s):

Sumit Gautam ◽

Shree Krishna Sharma ◽

Dinh-Hieu Tran ◽

Symeon Chatzinotas ◽

Bjorn Ottersten

Keyword(s):

Individual Performance ◽

Superior Performance ◽

Power Splitting ◽

Hybrid Scheme ◽

Efficient Manner ◽

Time Switching ◽

Weighted Utility ◽

Time Period ◽

Massive Number ◽

Iot Devices

<div>In order to support the massive number of resource-constrained Internet of Things (IoT) devices and machine-type devices, it is crucial to design future beyond 5G/6G wireless networks in an energy-efficient manner. To this end, this letter proposes a novel two-hop hybrid backscatter-and-relaying scheme to facilitate simultaneous wireless information and power transfer (SWIPT) considering both the Time-Switching (TS) and Power-Splitting (PS) receiver architectures, while dynamically modelling the involved dual-hop time-period (TP) metric. An optimization problem is formulated for the joint optimization of throughput, harvested energy, and transmit power of a SWIPT-enabled system with the proposed hybrid scheme, and is solved using a nonlinear optimizer. Our numerical results in terms of weighted utility function show the superior performance of proposed hybrid scheme over backscatter-only and relay-only schemes, while also depicting their individual performance benefits over the corresponding benchmark SWIPT systems designed with the fixed-TP.</div>

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Hybrid Active-and-Passive Relaying model for SWIPT-enabled 6G-IoT Greencom Networks

10.36227/techrxiv.12893750.v2 ◽

2020 ◽

Author(s):

Sumit Gautam ◽

Shree Krishna Sharma ◽

Dinh-Hieu Tran ◽

Symeon Chatzinotas ◽

Bjorn Ottersten

Keyword(s):

Individual Performance ◽

Superior Performance ◽

Power Splitting ◽

Hybrid Scheme ◽

Efficient Manner ◽

Time Switching ◽

Weighted Utility ◽

Time Period ◽

Massive Number ◽

Iot Devices

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Physical Layer Secrecy by Power Splitting and Jamming in Cooperative Multiple Relay Based on Energy Harvesting in Full-Duplex Network

Electronics ◽

10.3390/electronics11010040 ◽

2021 ◽

Vol 11 (1) ◽

pp. 40

Author(s):

Nabila Sehito ◽

Shouyi Yang ◽

Esraa Mousa Ali ◽

Muhammad Abbas Khan ◽

Raja Sohail Ahmed Larik ◽

...

Keyword(s):

Energy Harvesting ◽

Full Duplex ◽

Relay Network ◽

Power Splitting ◽

Amplify And Forward ◽

Secrecy Rate ◽

Decode And Forward ◽

Time Switching ◽

Source Signal ◽

Multiple Relay

In this article, we investigated the secrecy performance of a three-hop relay network system with Power Splitting (PS) and Energy Harvesting (EH). In the presence of one eavesdropper, a signal is transferred from source to destination with the help of a relay. The source signal transmits in full-duplex (FD) mood, jamming the relay transfer signals to the destination. The relay and source employ Time Switching (TS) and Energy Harvesting (EH) techniques to obtain the power from the power beacon. In this study, we compared the Secrecy Rate of two Cooperative Schemes, Amplify and Forward (AF) and Decode and Forward (DF), for both designed systems with the established EH and PS system. The Secrecy Rate was improved by 50.5% in the AF scheme and by 44.2% in the DF scheme between the relay and eavesdropper at 40 m apart for the proposed system in EH and PS. This simulation was performed using the Monto Carlo method in MATLAB.

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