Low Delay Gathering Scheme Design For Energy Harvesting Wireless Sensor Networks

The emergence of the energy harvesting wireless sensor network(EH-WSN)greatly alleviates the limited lifetime of wireless sensor networks.For the time being,there is a big gap between the energy harvested by node and that needed to support node’s normal operations.A node will harvest energy instead of forwarding data when it suffers from shortage of energy,which result in a longer data gathering delay.As a result it is important to design a data gathering scheme for EH-WSN to collect data with a lower delay.In this paper,we mainly studies the data gathering scheme of radio frequency energy harvesting wireless sensor network,and reduces the data gathering delay by adapting the node’s data load to it’s residual energy and energy harvesting power.The main work and innovation are as follow:1.When using the tree topology to collect the data in EH-WSN,some nodes need to harvest energy for a long time due to lack of energy,which seriously affects the data gathering delay.To this end,we define these nodes as “energy bottleneck node”,and use it to construct a data gathering tree.Then the energy consumption of nodes in a data collection cycle is calculated by applying the energy consumption model.According to the residual energy of the node and the energy harvesting power,the energy harvesting duration required by the node is deduced.Then we formed the network energy harvesting duration minimization problem.2.We propose a low delay data gathering scheme,and a data gathering tree construction algorithm for radio frequency EH-WSN.The algorithm uses the link weight that can reflect the energy harvesting power,the energy harvesting duration and the residual energy of the node,so that the link with a smaller weight has a priority to join the tree over the other ones.3.We compare our scheme with existing schemes by simulation.The simulation results show our scheme outperforms the existing scheme in terms of data gathering delay and energy consumption per packet.After that we analyze the effect of difference parameters on data gathering delay and energy consumption per packet.Then we improve the link weight with packet delivery ratio,and apply our scheme in the scenario of unreliable link.We also analyze the effect of difference parameters on throughput by simulation.