Joint Sampling Time and Resource Allocation for Power Efficiency in Industrial Cyber–Physical Systems

Cyber-physical systems (CPSs) form from convergence of computation, networking, and control of physical processes. In this article, the focus is on an industrial CPS consisting of many control plants and rate constrained (RC) users communicating over a single-cell orthogonal frequency-division multiple access network. We formulate a multiobjective mixed integer nonlinear optimization problem that seeks to determine the next maximum acceptable sampling moment of control plants and to minimize the energy usage in the uplinks and downlinks while taking into account the dynamics and intended performance of control plants, the quality of service of RC users, and power and subcarrier constraints. To address this problem, a decoupling approach is taken, leading to a Pareto solution. Our simulations show that the proposed scheme decreases the total power consumption in the CPS to a significant degree.