Research And Improvement Of WSN Algorithm Based LEACH

With the continuous development of information technology,wireless sensor networks has been widely used in intelligent home,traffic management,public safety and other aspects.Due to the limited energy of wireless sensor nodes,how to save the energy of sensor nodes and extending the lifecycle of wireless sensor network has become a growing concern in the academic world.Cluster protocol is well known for its good performance in energy saving and networks reliability improvement which includes communication latency reduction,collision avoiding and congestion.Some typical clustering protocols,such as LEACH has advantages in reusing same frequency band and expanding scalability.However,the network model of LEACH assumes that all sensor nodes are static and have known location,so LEACH is not suitable for wireless sensor networks with mobile nodes.In this thesis,we use two important indicators which are energy and packet transmission rate to explore more suitable for mobile nodes of the cluster routing protocol.Firstly,the architecture and node composition of wireless sensor network are introduced in detail,including the basic characteristics of wireless sensor network and the research of routing protocols.Secondly,two improvements are made to the LEACH protocol and the improvement of the LEACH protocol,and the LEACH-FLM algorithm is proposed.In the first aspect,the commonly used moving model is the random waypoint model,but the stochastic waypoint model lacks consideration of the actual diversity of each mobile node,that is,the one-dimensional velocity cannot accurately simulate the moving characteristics of sensor nodes.In order to make up for the above shortcomings,this thesis proposes a moving model based on stochastic waypoint model,which replaces the one-dimensional velocity of the random waypoint model with the velocity of three different dimensions.In the second aspect,the single factor of distance,energy and stability is taken into consideration in the random selection of the LEACH protocol in the cluster-head selection phase.The protocol adopts the fuzzy logic algorithm to take the distance,energy and stability into account.In this thesis,we use MATLAB simulation and set up five contrast groups which is LEACH protocol for static nodes,LEACH protocol for mobile nodes,LEACH-S for mobile nodes,LEACH-E for mobile nodes and LEACH-S for mobile nodes.The simulation results show that in terms of the number of dead nodes,the sum ofresidual energy and the fractional sum of successful arrival of the base station LEACH-FLM has excellent performance than other five different LEACH protocols,especially in saving energy of sensor nodes and improve the packet transfer rate.