Abstract:

Based on the scenario of railway Internet of things,the system outage performance of the relay network was analyzed,which was assisted with the power beacon (PB),using the half-duplex decode-and-forward relay mode over the Rician fading channel.In view of the equipment supply problems in railway scenes,such as difficult battery replacing,high management overhead,difficult wiring,etc.,the wireless energy collection was applied to railway scenes,providing sufficient and stable energy for the energy-constrained wireless equipment,thus solving the equipment supply problems in traditional railways.Considering that the source node and the relay node in the network were energy limited nodes,and the energy of the information transmission came from the radio frequency signal transmitted from the PB deployed on the train.The source node and the relay node collected energy from the PB,and the source node sent information to the relay node by using the collected energy,and then the relay node forwarded the information received to the destination node.The closed-form expressions of the network end-to-end outage probability and the throughput were derived.The analytical results were demonstrated by Monte Carlo simulation.And based on this analysis,the impact of the ratio of transmitting power of the PB to noise,the Rician K-factor,the time switching factor,transmission rate and relative position on the end-to-end outage probability and throughput were studied.When the train is in the middle of the source node and the relay node,the system can obtain better outage and throughput performance.

Key words: energy harvesting, power beacon, Rician fading channel, half-duplex, outage probability, throughput, railway Internet of things