Performance Analysis Of Relay Network Assisted By Radio Frequency Power Beacon

With the rapid development of the Internet of Things,there are more and more wireless devices in the network,and the energy consumption of devices is becoming increasingly important.Traditional battery power network can't guarantee the long-term operation of the network because of its limited energy and hard to replace in extreme environment.However,radio frequency energy harvesting technology can provide stable energy,easy management and it can solve the problems of limited energy of wireless devices,difficult to replace in extreme environments and the high cost of manual maintenance.Therefore,it has become a hot spot in the research of wireless network.Combined with wireless relay technology,it can further expand the network coverage,improve the system capacity and enhance the reliability of long-distance data transmission.The energy harvesting relay networks usually use the source node as the energy source to provide energy for the nodes with limited energy.However,in most network scenarios,the energy of the source node is also limited,so a new way of deploying dedicated wireless radio-frequency power beacon(PB)to provide energy for the nodes with limited energy in the area emerges.Most of the existing researches are focused on Rayleigh fading channel or Nakagami-m fading channel,but in the actual wireless energy transmission,the energy mainly comes from the direct component,and the sight distance transmission can't be ignored.In short,the Rician fading channel model should be more practical in the wireless energy harvesting network,so this paper investigates the system performance of the wireless radio-frequency power beacon assisted energy harvesting relay network in two relay modes based on the Rician fading channel,the specific work contents are as follows:(1)For the half-duplex relay network with wireless radio-frequency power beacon assisted,this paper analyzes the system performance of the relay using decode and forward mode in the Rician fading channel based on the traditional linear energy harvesting model,and deduces the closed expressions of the system outage probability and throughput.The correctness of the theoretical analysis is verified by comparing the Monte Carlo simulation results with the numerical results.The result shows that the larger the ratio of PB transmitting power to noise power,the smaller the system outage probability is and the larger the throughput is;the larger the Rician K-factor,the smaller the system outage probability is and the larger the throughput is;in the process of increasing the time switching factor from 0 to 1,the outage probability first decreases and then increases,while the throughput first increases and then decreases;the smaller the system minimum required transmission rate,the smaller the outage probability is;the larger the energy conversion efficiency,the smaller the system outage probability is,and the larger the throughput is.(2)For the full-duplex relay network assisted by wireless radio-frequency power beacon,the system performance of the relay using decoding and forwarding mode is also analyzed based on the traditional linear energy collection model in the Rician fading channel.The closed expressions of the system outage probability and throughput are derived,and the asymptotic expression of the system outage probability under the condition of high SNR at the PB and the expression of the system outage probability under the condition of strong relay SIC capability are obtained.Finally,the correctness of the theoretical analysis is proved by Monte Carlo method.The simulation shows that the larger the ratio of PB transmitting power to noise power,the smaller the system outage probability is and finally it tends to be stable,while the larger the throughput is;the larger the Rician K-factor,the smaller the system outage probability is and the larger the throughput is;as the time switching factor increases from 0 to 1,the outage probability of the system decreases first and then increases,while the throughput increases first and then decreases;the smaller the system minimum required transmission rate,the smaller the outage probability is;the larger the energy conversion efficiency,the smaller the system outage probability is and the larger the throughput is;the stronger the relay SIC capability,the smaller the system outage probability is and the larger the throughput is.Moreover,the impact of the relay SIC capability on the system outage performance is limited,under the certain ratio of PB transmitting power to noise power,increasing the relay SIC capability can't improve the system outage performance continuously.