基于TCP/AQM的离散滑模控制器设计

Discrete Sliding Mode Controller Design for Active Queue Management

基于网络拥塞控制有效的主动队列管理算法(AQM),设计了一种鲁棒的离散滑模控制器(DSMC)。针对实际网络中离散化的采样系统和定期更新等运行特点,将TCP动态拥塞窗口模型离散化,考虑该模型存在的网络延迟及流量扰动等参数不确定等特点,采用鲁棒性较好的滑模控制器。在控制器的设计中,构造了包含起始点滑模面,缩短到达时间;假设不确定扰动的最大上界,采用等效控制设计控制律;然后给出了系统的稳定性分析。仿真结果表明该控制器能够获得较快的响应速度和稳定的队列长度,在网络参数变化时仍能获得很好的鲁棒性。

A robust discrete sliding model controller （DSMC） was proposed based on an active queue management （AQM）, which is an effective network congestion scheme. Considering the discrete sampling system and regular update, first, discreting dynamic TCP congestion model and then, a new sliding mode controller was designed for the uncertainties and disturbances in the network. During the design of controller, sliding mode contained the initial nodes in order to shorten the arriving time, giving the max bounds of varying fluctuations and disturbances, an equal control was used, and then proving the system is steady in theory. Simulation results demonstrate that good transient and steady state queue responses can be obtained by applying the proposed controller .The results also show that the scheme is very robust to disturbance under various network conditions.