Research On The Performance Of Simultaneous Wireless Information And Power Transfer System Based On Decode And Forward Relay

In wireless networks,because of the node's limited energy and it is difficult to replace the battery in the complex application environment,so that the lifetime of the node will be restricted by the node energy.To solve this problem,the traditional solution is to use energy-efficient modulation,energy-efficient routing algorithm and energy-efficient communication to prolong the survival time of the node.In recent years,with the wireless power transfer technology mature gradually,the simultaneous wireless information and power transfer technology which applies the wireless power transfer technology on node has been widely concerned,its core idea is to use radio-frequency signal can carry information and energy simultaneously to implement simultaneous wireless information and power transfer.The emergence of the simultaneous wireless information and power transfer technology enables the node harvests energy continuously,which achieves the infinite extension of the node's lifetime.In three-node simultaneous wireless information and power transfer system,which consists of a source node,a relay node,and a destination node,the relay node is an energy constrain node,it needs to harvest the energy from the radio frequency signal to start work,so the relay node first harvest energy from the received radio frequency signal and obtain information,then use all the harvested energy to forward the information to the destination node.Aim at this energy harvesting system,current research proposes two relaying protocol,i.e.time switching relaying protocol and power splitting relaying protocol.This paper mainly studies the three-node simultaneous wireless information and power transfer system based decode-and-forward relay,its content includes two works as below:1)With considering the relay circuit power in three-node simultaneous wireless information and power transfer system,this paper analyzes the system performance on both time switching and power splitting relaying protocols,studies the impact of circuit power on system performance.Simulation results show that the system performance will reduce with the existence of relay circuit power;the energy harvesting parameter will reach a new optimal value in the presence of circuit power;circuit power does not have an impact on the rate value of the two protocols' optimal throughput intersection,but the effect on time switching protocol is greater than power splitting protocol in low transmission rate.2)On the premise of all the transmission signal can be forwarded by relay,rate adaptive power splitting relaying protocol is proposed on the basis of power splitting relaying protocol,and derives the expression of outage probability and throughput on this protocol.Simulation results show that the proposed protocol can achieve a better throughput performance than power splitting protocol.