Design And Optimization Of Balanced Strategy For Information Transmission And Energy Harvesting In Green SWIPT Network

Simultaneous Wireless Information and Power Transfer(SWIPT)is proposed as a promising technology in wireless communication to address the problem of energy scarcity in energy-constrained networks.Different from traditional networks powered by external power sources,SWIPT nodes can harvest energy from the received radio frequency(RF)signals and use the harvested energy for information transmission,which hurdles the dependence of informaiton transmission on external power supply.SWIPT can significantly enhance the performance of energy efficiency and spectral efficiency as well as reduce the transmission latency.How to make a tradeoff between information transmission and energy harvesting has become a research hotspot in SWIPT network.This dissertation investigates the design and optimization of tradeoff strategy between information transmission and energy harvesting in green SWIPT network.Different information transmission and energy harvesting tradeoff strategies in different SWIPT network scenarios are studied.The main research aspects of this dissertation are shown as below.1)nonlinear energy harvesting model and a SWIPT transmission scheme——intelligent cooperation of time switching and static power splitting(Co TP)are studied.Rate-energy(R-E)region of the scheme is derived,and the corresponding R-E tradeoff strategy of Co TP scheme with circuit power consumption at the receiver is investigated.In addition,R-E region performance comparisons between the proposed Co TP scheme,dynamic power splitting(DPS),on-off power splitting(OPS),static power splitting(SPS)and time switching strategy(TS)are presented.The effects of noise and circuit power consumption at the receiver are analyzed via simulation performance.The proposed Co TP scheme obtains higher achievable rates when the harvested energy per bit ranges from 0m J to 1.5m J with the consideration of circuit power consumption,which can realize the tradeoff between energy harvesting and information transmission.2)The optimization method of R-E region in multi-node multi-antenna green SWIPT network based on OPS structure is investigated.Considering SWIPT network with one multi-antenna transmitter and multiple single-antenna receiver,we set the maximization of multiple OPS receiver harvested energy as the optimization objective and construct system optimization model.System peroformance can achieve the requirements via the reasonable design of power splitting ratio,time slot factor,and beamforming vector.Simulation results show that,by the increasing of transmitter antenna or SWIPT node numbers at the receiver,the proposed OPS-based scheme obtains wider R-E region compared with TS-based scheme.3)Secure information transmission and energy harvesting tradeoff in green SWIPT network with eavesdropping interference is studied.When eavesdropping interference is existed in SWIPT network,the receiver transmits artificial noise that is orthogonal with the transmitted signals to interfere with the eavesdropper,and the jamming signal can provide energy for SWIPT relay at the same time.SWIPT relay implements power splitting scheme and beamforming to realize secure information transmission.The joint optimization of beamforming vector and power splitting factor achieves to obtain the maximum achievable secure rate.Simulation results show that the proposed scheme realizes the tradeoff of secure information transmission and energy harvesting via the design of appropriate beamforming vector and the selection of suitable power splitting factor.This dissertation studies the design and optimization of tradeoff strategy of information transmission and energy harvesting in green SWIPT network,and the research achievements provide significant value for the further related works.