Multi-channel Adaptive Multiple Access Protocol Based On Clustering In Uanet

With the continuous improvement of unmanned aerial vehicles ad hoc network(UANET)and 5th Generation Mobile Communication Technology(5G),it has been widely used in various fields(such as business,emergency response,civil,military,etc.).In these applications,technological innovation is the basis,research in protocols and standards are the direction.As the number of nodes increases,the performance of UANET will decline,and the quality of service(QoS)guarantee cannot be provided at present.In practical application and many literatures,it is suggested to adopt the clustering network structure when the number of UAV nodes can be clustered,so as to solve the problem of performance degradation of UANET.The main research contents of this paper are as follows:1)Through consulting a large number of literature and in-depth research of science and technology,the necessity of adopting clustering network layout scenario in high dynamic,large-scale UANET has been identified.By analyzing and exploring the stability and throughput degradation of existing clustering algorithm,the key problems affecting network performance when the number of nodes increases in such scenarios are proposed.2)Aiming at the problem of unstable clustering algorithm of high dynamic and large-scale UANET,in this paper,a fuzzy inference system is introduced,which considers the relative speed of nodes,the quality of data received and the remaining energy of nodes as the fuzzy input parameters,designs the fuzzy rules,and obtains the final output result to evaluate the ability of nodes as cluster heads.Then,the process of cluster head election,the process of node leaves and join clustering and the strategy of cluster head replacement based on the cluster head coefficient are analyzed and designed in detail.Based on the advantages of high flexibility,high robustness and strong error tolerance of fuzzy inference system,several factors affecting the global stability of clustering structure in UANET are coupled efficiently and stably.Simulation results show that the fuzzy logic clustering algorithm is superior to traditional clustering algorithm in terms of number of clusters and average lifetime of cluster heads.3)Aiming at the problem that the throughput of the system in the cluster decreases due to a large number of UAV nodes,a multi access protocol based on time-frequency-spatial multiplexing is proposed.The fast and reliable transmission of secure messages is realized through the high priority access mechanism on the control channel.In CCHI,SCHI time slots are reserved,and channel period allocation ratio is adjusted adaptively according to network load to improve the utilization of time slot resources.Power control based on position prediction and multi-channel reservation are implemented to realize parallel transmission in frequency domain.Based on the intelligent multi-beam antenna mode switching scheme,the spatial reuse degree is improved.Finally,OMNeT++software is used to build a communication simulation framework suitable for UANET,and the clustering algorithm and multiple access protocol mentioned above are realized.Simulation results show that the throughput of multiple access protocol based on time-frequency-spatial multiplexing proposed in this paper is better than that of CSMA/CA,and the security message delay and end-to-end delay are better than IEEE1609.4.