Research On Hybrid Multiple Access Protocol For Link-16

The multiple access control(MAC)protocol of data link describes the rules that the nodes need to observe when the nodes are connected to the shared channel,which is very important to the fair,rational and efficient utilization of network resources.The MAC protocol of Link-16 data link is TDMA(Time Division Multiple Access)fixed multiple access protocol.Under this protocol,all network nodes are allocated fixed timeslots for message sending,and messages can only be received in other time slots.In this mode,the burst message of the node may need to wait for a long time to transmit,which leads to higher transmission delay,and if no message needs to be sent in a pre-specified time slot,the other nodes can not take up the time slot,so the utilization rate of time slot is low.In order to solve this problem,this paper summarizes the current research status and hot spot,and studies the hybrid multiple access design method which combines different access protocols.Based on the structure of TDMA,two hybrid multiple access algorithms are designed.The algorithms are used to solve the problem of high transmission delay and low utilization of time slot.The main contents of the thesis are as follows:First,before the design of the hybrid multiple access algorithm,the theory of multiple access technology and the MAC protocol of a variety of data link are analyzed.Through the research on the slot allocation structure of Link-16 data link,illustrated by solid and dynamic combination of hybrid multiple access design is reasonable.Second,a hybrid multiple access algorithm combining fixed multiple access and random multiple access is designed.The algorithm uses TDMA fixed multiple access protocol for the transmission of periodic message,and uses slotted-aloha random access protocol for the transmission of burst message.In this paper,based on the characteristics of fixed multiple access and random multiple access,the performance of the algorithm is analyzed from the system throughput level on the premise of guaranteeing the transmission delay of a certain periodic message and the passing rate of the burst message.The theoretical and simulation analysis shows that the algorithm can meet the transmission requirements of the periodic message and the burst message simultaneously,and the throughput of the system is higher than the TDMA fixed multiple access protocol under certain conditions,and the utilization rate of the time slot is improved.In the end,because the fixed and random hybrid multiple access algorithm is easy to lose packet after the message collision,and the data link message is of different importance,so a hybrid multiple access algorithm based on the message priority is proposed.The algorithm still uses the TDMA fixed multiple access protocol to complete the transmission of the periodic message.For the burst message,the different priority is set according to the difference of its importance,thus the sequence of message transmission is determined.In this paper,based on queuing theory,the transmission strategy of higher priority message priority access channel is designed.Through theoretical and simulation analysis,the higher priority of the message and shorter time delay,which avoids the loss of important message.At the same time,the message delay of the hybrid multiple access protocol is obviously lower than that of TDMA fixed multiple access protocol.The time slot utilization ratio of the multiple access protocol is significantly improved.Compared to the single access mode,the hybrid multiple access algorithm has better transmission performance,and provides a powerful reference for the improvement of the tactical data link MAC protocol.