Joint Resource Optimization in Simultaneous Wireless Information and Power Transfer (SWIPT) Enabled MultiRelay Internet of Things (IoT) System
Abstract
:1. Introduction
 We consider a multirelay OFDM based IoT system, in which the SWIPTenabled relay can decode information and harvest energy simultaneously. Therefore, the splitter does not have to be installed in the relay, which is necessary in the common algorithm using PS or TS protocol. It can simplify the deployment and administration of the IoT system.
 We formulate a scheme by optimizing power and subcarrier allocation with the aim at maximizing the transmission rate, and employ the timesharing strategy and Lagrange dual method to solve this optimization problem.
 Simulation results illustrate the effectiveness of our algorithm. By observing the transmission rate, it illustrates that the proposed algorithm has better performance than other algorithms.
2. Review Conclusion
3. System Model and Problem Formulation
4. Optimal Resource Allocation
4.1. Optimizing the Dual Function
4.2. Optimizing Primal Variables at a Given Dual Point
Algorithm 1 Proposed Algorithm for P2 

5. Simulation Results and Analysis
Algorithm 2 

Algorithm 3 

Algorithm 4 

6. Conclusions
Author Contributions
Acknowledgments
Conflicts of Interest
References
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Lu, W.; Liu, G.; Si, P.; Zhang, G.; Li, B.; Peng, H. Joint Resource Optimization in Simultaneous Wireless Information and Power Transfer (SWIPT) Enabled MultiRelay Internet of Things (IoT) System. Sensors 2019, 19, 2536. https://doi.org/10.3390/s19112536
Lu W, Liu G, Si P, Zhang G, Li B, Peng H. Joint Resource Optimization in Simultaneous Wireless Information and Power Transfer (SWIPT) Enabled MultiRelay Internet of Things (IoT) System. Sensors. 2019; 19(11):2536. https://doi.org/10.3390/s19112536
Chicago/Turabian StyleLu, Weidang, Guangzhe Liu, Peiyuan Si, Guanghua Zhang, Bo Li, and Hong Peng. 2019. "Joint Resource Optimization in Simultaneous Wireless Information and Power Transfer (SWIPT) Enabled MultiRelay Internet of Things (IoT) System" Sensors 19, no. 11: 2536. https://doi.org/10.3390/s19112536