Study Of Load Balancing Techniques For Wireless Sensor Networks

Wireless Sensor Networks(WSNs),as a kind of smart data collecting network,are widely used in a number of applications such as environment monitoring,battlefield detections,and city monitoring and are emerging as a foundamental information infrastructure for future techniques like smart city and IoTs(Internet of Things).The network lifetime expansion and network load balancing have always been critical research issues for unattended WSNs because of the tight power budget of sensor nodes.This paper focuses on network topology optimization and dynamic routing to balance workloads among sensors and expand the network lifetime for the improvement of network efficiency.Compressive Sensing(CS)is emerging as a novel compressive sampling technique and was in recent years applied to the field of data collecting in WSNs.This paper exploits a kind of Hybrid Clustering strategy in Compressive Sensing WSNs(called HCCS).HCCS divides the whole network into two parts,that is,VIA(Very Important Area)and GA(General Area),and adopts flat routing and clustering routing respectively.The VIA is just the monitoring area where sensor nodes are close to the Sink and those nodes tend to run out of energy much earlier than nodes in other areas.And the earlier death of the nodes in VIA will disrupt the network connection because nodes that are distant to Sink will fail to connect to the Sink without data traffic delaying by VIA nodes.In order to solve this problem,HCCS firstly models the energy consumption of VIA nodes and then proposes an area division model that aims at minimizing the average energy consumption of VIA nodes.Secondly,HCCS considers load balanced routing in VIA.To avoid the early death of those nodes that bears more data traffics in VIA,HCCS proposes an optimal data traffic allocation strategy(i.e.NLMDA)to maximize the lifetime of delaying nodes.And further,this paper proves that the NLMDA is a linear programming problem and gives a load balanced distributed multi-path flat routing algorithm based on NLMDA.Then,this paper exploits clustering algorithm design in the GA area.For the purpose of global energy consumption minimization,HCCS discusses the best clustering radius in compressive sensing WSNs and presents a multi-hop clustering algorithm based on HEED.Finally,this paper carries out extensive simulations to validate those conclusions and algorithms proposed in this paper.Simulation results validate the VIA division model and show that HCCS can efficiently balance the workload and extend the network lifetime in compressive sensing WSNs.