Research On Key Technologies Of On-Demand Routing In Multi-Channel MANET

Mobile Ad Hoc Network(MANET)has the characteristics of centerless,selforganizing,multi-hop routing,dynamic topology,etc.,which is widely used in military exercise,emergency communication and other fields.The traditional MANET network uses a single channel,which severely restricts the network performance.Multi-Channel Multi-Interface(MIMC)technology can effectively reduce access conflicts and expand network capacity.However,unreasonable channel allocation methods and routing algorithms waste system resources.In addition,the speciality and complexity of MANET make QoS guarantees for high-priority services more difficult.In view of the above problems,this paper proposes a channel allocation and routing joint algorithm BP-JCAR that supports priority-differentiated bandwidth prediction,which mainly includes three aspects:Firstly,a queue scheduling and bandwidth prediction model for high priority service QoS guarantee is established.This paper designs data transmission queues for different types of services,proposes a proportional fair scheduling algorithm,and configures scheduling opportunities for each queue according to priority weights.This paper also derives the maximum available bandwidth calculation formula that the node can obtain at the current time.It can consider the channel contention and service type of neighboring nodes and provide different levels of available bandwidth prediction.The simulation results show that with the same number of traffic streams and equal transmission rates,high-priority services have higher effective throughput and lower average delay than lower-priority services as the network load increases.Secondly,a MIMC distributed MANET channel allocation scheme is designed.BPJCAR divides the interfaces into a control interface and multiple data interfaces,which are used to transmit control messages and general data respectively.Besides,The scheme allows the data interface to dynamically switch its working mode.In this paper,the physical interference and protocol interference of the wireless channel are considered comprehensively,and the channel interference degree calculation formula is derived.The simulation results show that under the condition of 3-interfaces 4-channel single-hop data flow,the proposed algorithm has 3-4 times better performance than the single-interface single-channel scheme,and has 12%~15% performance improvement over the existing typical algorithm.Thirdly,a cross-layer design scheme for channel allocation and routing that supports priority processing is proposed.Based on AODV,BP-JCAR combines channel allocation and routing protocols with the idea of cross-layer design,and designs the optimal path by considering the route metrics of link interference and path length.The simulation results show that under the condition of 3-interfaces 12-channel multi-hop data flow,the proposed algorithm has 17%~25% performance improvement.The above research results can be used in wireless MANET network protocol design,which has theoretical and practical significance for network optimization in multi-channel environment.