Research On Cross-layer Congestion Control Technology Of Tactical Data Link

Tactical data link(TDL)has the characteristics of fast networking,high performance,and long-distance transmission in modern warfare.It is mainly deployed in airborne equipment,such as drones,and it could be used for battlefield situation awareness,image acquisition,data interaction and command transmission.The TDL can achieve a high transmission success rate,with a low delay at the same time,but the complex and changing battlefield may affect its performance.Current research focuses on modeling and analysis of a specific problem in the TDL,lacking a comprehensive simulation of the model.Therefore,it is necessary to further build a simulation platform that can capture the characteristics of complex changing scenes.Besides,the current mainstream optimization algorithms only revolve around single layer networks,and lack cross-layer information interaction and cross-layer optimization strategies.The cross-layer optimization strategy of the TDL is discussed and studied deeply in this article.Firstly,this article introduces the system architecture and protocol model of the TDL.Then,we realize the statistical priority-based multiple access mechanism(SPMA),the encapsulation of communication pipeline and data unit based on the network simulator 3(NS3).After completing the construction of the TDL model,we further analyze the performance indicators of the model.Secondly,two simulation scenes based on routing reconstruction and dynamic error code are simulated to analyze the performance of the TDL in a complex network.The two scenarios modify the speed and distance of tactical nodes by the mobility model and change the link error code dynamically base on the network layer and the data link layer.So the two simulation scenes of route reconstruction and dynamic error code are realized.Finally,based on the problem of performance degradation of TDL in complex networks,the cross-layer congestion control algorithm based on routing stability and the cross-layer congestion control algorithm based on link quality are proposed.Thereinto,the first algorithm detects routing failure packets at the network layer to obtain the frequency of route reconstruction which can be used to evaluate the routing stability.The routing stability information can be transferred to the transport layer through the communication pipeline,so that the transport layer can distinguish the cause of the current data loss and avoid the unnecessary reduction of the congestion window effectively.And the second algorithm adaptively adjusts the congestion control window by obtaining the count of automatic repeat-request(ARQ)at the link layer.At the same time,the sequence number of the retransmitted data packet is fed back to the transport layer to prevent the data packet from being repeatedly retransmitted.The simulation results show that the proposed algorithms in this article can effectively improve the system performance of the TDL compared with the existing methods.