Sampling frequency optimization in wireless sensor network-based control system

The application of wireless sensor network in control systems can bring some advantages, such as the flexibility and the feasibility of network deployment at low costs. While it also raises some new challenges. First, the limited communication resources are shared by several control loops. Second, the wireless and multi-hop character of sensor network makes the resources scheduling more difficult. Thus, how to allocate the limited communication and computing resources effectively is an important problem. In this paper, this problem is formulated as ail optimal sampling frequency assignment problem, where the objective function is to maximize the effectiveness of control systems, subject to channel capacity constraints. Then an iterative distributed algorithm based on local buffer information is proposed, which has features of low computational complexity and well scalability. Finally, the simulation results show that the proposed solution can achieve the optimal quality of the control system in a distributed way. Meanwhile, it is capable of seeking the optimal point automatically when the network load changes.