Research On Cross Layer Protocol Design And Data Fusion In Wireless Ad Hoc Networks

In latest years,with the fast development of wireless communication technology,the related wireless sensor network technologies have also been continuously innovated and popularized,and these technologies are increasingly applied to various scenarios,such as indoor and outdoor environment monitoring,intelligent agriculture and industrial equipment status monitoring.However,in some specific field environment monitoring scenarios,such as power grid,river monitoring,sensors and signal transmission equipment are distributed in a geographic area that is approximately zonal.In this scenario,higher requirements are put forward for the network structure,networking mode and data transmission of wireless ad hoc networks.It is necessary to take into account the low power consumption of the overall network,the stability of data transmission and Quality of Service(Qo S).Therefore,for this sort of scenario,this thesis constructs a hierarchical structure of wireless ad hoc network,and designs the wireless ad hoc network cross-layer protocol and in-network sensor data fusion algorithm based on this structure.This thesis first summarizes the advantages and disadvantages of different wireless ad hoc networks through the analysis and comparison of different wireless ad hoc network structures,designs a hierarchical wireless ad hoc network structure that combines cluster network and chain network,and carries out cross-layer optimization for this type of network structure.The cross-layer optimization mainly includes the following two aspects:First,the parameters in physical and link layer are analyzed for example the packet loss,then the physical layer and link layer parameters such as transmission power and data rate of each node are adaptively adjusted in real time; Second,for the data congestion of cluster head nodes in this structure,the physical layer and other parameters are considered in the sub cluster head election process of the network layer,so that the sub cluster head can be generated to establish an alternative path to alleviate congestion.Through the simulation,we can see that it can not only reduce the data congestion rate,but also better improve the network life and information quality in the effective period.Based on the above network structure,this thesis probes into the in-network data fusion method,calculating to reduce the amount of data between clusters to cut down the energy depletion.Then we design an optimization algorithm based on D-S evidence theory.This method is optimized from three aspects:data screening from original data sources,correction of conflicting evidence from evidence source and composition rule,which improve the accuracy of judging results.And the optimization algorithm designed in this thesis has lower computational complexity,and has greater advantages when deployed in scenarios that require lower power consumption and delay.Finally,based on the aforementioned cross-layer design and data fusion algorithm,this thesis designs a set of cross-layer communication protocol,and carries out the overall performance evaluation and analysis the result of the cross-layer communication protocol and in-network optimization algorithm based on D-S evidence theory.The results prove that the protocol and algorithm put forward in this thesis can efficaciously balance the energy consumption of nodes during the operation of wireless ad hoc network,So as to prolong the life of the whole network and improve the information quality within the effective period.