Minimax Controller Design Based on AQM $$ Scheme for TCP Network Systems

This paper proposes an active queue management (AQM) controller based on the Minimax method for a class of nonlinear TCP network congestion system in the presence of uncertain parameters and unknown external disturbances. At the same time, an output feedback controller which guarantee the queue length stability and robustness, is specially designed with considering the situation that the system got the max impact when being disturbed by Lyapunov stability theory. The restriction of assumption inequality is eliminated by introducing the Minimax method into TCP network system. The simulation results show that the proposed control strategy is effective to improve the transient stability and robustness of the system.