Interference Aware Data Delivery Scheme For Energy-harvesting Wireless Sensor Networks

Energy Harvesting Wireless Sensor Network(EH-WSN)is an important component of the Internet of Things(IoT).The basic task of EH-WSNs is to deliver data sensed by the nodes.Delivering data with low delay has become an important research subjects.Based on the interference phenomenon between wireless links in EH-WSNs we research the low delay data delivery scheme.The main works and innovations are as follow:(1)In terms of the interference between wireless links and the data load distribution of an EH-WSN and the energy harvesting rate of the node in an EH-WSN can all make influences on the time for all nodes delivering their data to the sink which means the delay of data gathering,we define a weight for wireless links which takes all the three aspects into consideration.Then,we present a heuristic algorithm by using the weight of wireless link to build a low delay and interference aware data gathering tree which aims to choose the node that makes the weight of wireless link the smallest to join the data gathering tree with the highest priority.(2)In order to further reduce the data delivery delay,we propose a data delivery scheme based on the data gathering tree we build.In the scheme we use the TDMA(Time Division Multiple Access)mechanism.We schedule the wireless links that in the data gathering tree and allocate property timeslot and transmission power to them to make sure that all the wireless links scheduled in a same timeslot can transmit data together and don't interfere with each other.Then,we translate the problem of link schedule and transmission power allocation into an optimization problem and propose a heuristic algorithm to solve the optimization problem.(3)Simulation is executed based on the data gathering tree building algorithm and the data delivery scheme by using MATLAB.We also make a comparison with the Low Latency High Compatibilty(LLHC)algorithm.Then,we analysis the effects that the number of nodes and the threshold value of SINR and the time-slot length make on the data gathering delay.The results of the simulations indicate that the algorithm of building data gathering tree and the data delivery scheme we proposed can get a lower data delivery delay than LLHC.