Design And Implementation Of Wireless Ad Hoc Network Routing Protocol Based On Network Environment Awareness

Wireless Ad Hoc Networks(Wireless Ad Hoc Networks),referred to as Ad Hoc network or MANET,has a high degree of autonomy and has a wide range of application prospects in the military and civilian fields.However,the highly dynamic nature of the network and the complexity of the wireless network environment pose a severe challenge to finding a path for information forwarding.Based on the requirements of the project scenario,thesis,combined with the consideration of the impact of the wireless network environment on the network performance,conducts research on the Ad Hoc network routing protocol,and designs a routing protocol that meets the needs of the project scenario.First of all,thesis designs a hybrid routing protocol BH-HRP based on the number of hops for project scenarios where nodes have frequent business interaction requirements in a local area,combining the advantages of active routing protocols and on-demand routing protocols.Through the BH-HRP protocol,any node can complete real-time information interaction with its neighbors(within two hops)that are close to each other,and remote nodes(above two hops)adopt an on-demand routing strategy to reduce information transmission overhead.The simulation results show that the BH-HRP protocol can compromise routing control overhead and end-to-end delay.Considering the differences in node mobility and end-to-end link quality,thesis introduces network environment awareness,and proposes network environment indicators describing wireless links,network topology and node status,namely link quality,topology stability,node load and The remaining energy of the node.Based on these indicators,the classic MPR selection algorithm is improved.The improved MPR algorithm preferentially selects nodes with excellent link quality,good local topology stability,more node remaining energy,and node load not exceeding the load threshold as MPR nodes,which is more suitable for wireless network scenarios.Based on the topology stability index,the Hello cycle adaptive adjustment strategy is designed.When the topology changes drastically,this strategy enables nodes to quickly discover topology changes and update neighbor relationships in time.When the topology is stable,it can reduce the overhead of the Hello mechanism.On this basis,the BH-HRP protocol is optimized,and a hybrid routing protocol BNHRP based on network environment awareness is designed.The BN-HRP protocol takes link quality as the basic routing metric,increases routing learning mechanism and routing hot discovery mechanism,and reduces the waiting time of routing requests.Through the perception of the network environment,the improved MPR algorithm is used to realize multi-path routing discovery and dynamic routing selection based on the network environment,and improve the adaptability of routing protocols to the complex and changeable wireless network environment.Finally,the BN-HRP protocol was simulated and verified in the NS3 simulation platform.The simulation results show that the BN-HRP protocol improves the packet delivery rate,while reducing the data transmission delay,and the overhead performance is significantly better than the OLSR protocol.In particular,in a scenario where the node moves at a medium or low speed,the energy consumption of the node is relatively balanced.In addition,in response to the needs of large-scale hardware-in-the-loop simulation of the project,a method of quickly transplanting modules in NS3 to run on physical nodes is proposed,and the method of building a distributed hardware-in-theloop simulation platform is described,which can be used for the subsequent implementation of large-scale semi-physical The physical simulation verification has laid a good foundation.