信息传输如何影响网络控制系统的性能,是控制理论界尚未解决的重要问题之一.本文尝试采用Shannon提出的失真评价函数、统计偏差和熵的定义,结合传统采样和网络传输理论,从统计概率的角度,证明了当网络传输受限时,网络采样控制系统性能损失和传输采样信息量之间存在倒数关系,建立了定量计算网络带宽变化量改变控制系统输入输出的方法.并通过Simulink中Truetime网络系统仿真软件验证了该方法的有效性.
The effect of the information transmission on the performances of a networked sampling control system is an unsolved problem in control theories. This problem can not be dealt with by the traditional sampling and transmission theories. By combining the traditional sampling theory and the network transmission theory with Shannon's signal fidelity evaluation, signal statistical signal deviation and the definition of entropy, we prove that the deterioration in performance index of the networked sampling control system is inversely proportional to the amount of the sampled information in transmission, and statistically determine the amount of changes in inputs and outputs of the networked sampling control system caused by the bandwidth constraint. The network simulation tool Truetime in Simulink has been employed in simulation to verify the proposed method.