基于CMAC-PID并行控制的主动队列管理方法

主动队列管理对于解决日益严重的网络拥塞问题具有极其重要的意义。本文针对PID主动队列管理算法的参数整定难且不能实时调整,不能适应复杂、非线性网络环境的缺点,提出了一种基于小脑神经网络(CMAC)与PID控制相结合的主动队列管理算法。该算法利用CMAC前馈补偿来确保跟踪误差的快速收敛,降低超调量,采用PID控制器实现回馈控制,保证系统的稳定性,而且抑制扰动。仿真结果表明,基于CMAC-PID并行控制的主动队列管理方法适应于多变的网络环境,较之常规PID主动队列管理算法具有输出误差小、响应速度快、鲁棒性强的优点。

An Active Queue Management Algorithm Based on the CMAC-PID Parallel Control

Active queue management (AQM) is very significant for network congestion. This paper presents a new algorithm based on the CMAC and PID parallel control to overcome the shortcomings of PID AQM:parameter cannot be adjusted with time,cannot be adapted to the complicated and nonlinear network environments. This algorithm uses CMAC as feed-forward compensation to ensure the tracking of the fast convergence of errors and reduce the overshoot,uses the PID controller as feed-backward compensation to ensure the stability of the system and restrain disturbance. The results of simulation show that the AQM algorithm based on the CMAC-PID parallel control can adapt to the changing network environment and has lower output error,faster response speed and better robustness than the conventional PID AQM algorithm.