Leveraging Linear Quadratic Regulator Cost and Energy Consumption for Ultrareliable and Low-Latency IoT Control Systems
Haojun Yang, Kuan Zhang, Kan Zheng, Yi Qian
Abstract
To efficiently support real-time control applications, networked control systems operating with ultrareliable and low-latency communications (URLLCs) become a fundamental technology for the future Internet of Things (IoT). However, the design of control, sensing, and communications is generally isolated at present. In this article, we investigate the joint optimization of control cost and energy consumption for a centralized wireless networked control system. Specifically, with the “sensing-then-control” protocol, we first develop an optimization framework that jointly takes control, sensing, and communications into account. In this framework, we derive the spectral efficiency, linear quadratic regulator cost, and energy consumption. Then, a novel performance metric called the energy-to-control efficiency (ECE) is proposed for the IoT control system. In addition, we optimize the ECE while guaranteeing the requirements of URLLCs, thereupon a general and complex max-min joint optimization problem is formulated for the IoT control system. To optimally solve the formulated problem by reasonable complexity, we propose two radio resource allocation algorithms. Finally, simulation results show that our proposed algorithms can significantly improve the ECE for the IoT control system with URLLCs.