A Bandwidth Allocation Strategy Based on Multirate Sampling Method in Networked Control System

Considering the resource constraint, a bandwidth allocation strategy with multirate sampling method is proposed to achieve the control and scheduling codesign of networked control system (NCS). The bandwidth allocation strategy integrates static scheduling method with dynamic scheduling method. Final bandwidth of each closed loop is determined by three steps. Firstly, the basic sampling period is selected based on the maximum available bandwidth of network. Then, the initial bandwidth allocation method is given on the basis of the sampling period which is determined by the different characteristics of each closed loop and the central bandwidth can be obtained in this step. At last, the final bandwidth can also be adjusted dynamically on the basis of the state change of each plant. In order to verify the validity of this bandwidth allocation strategy, the stability of control system and the bandwidth utilization of network system are shown through simulation experiments.