VoI-Aware Energy-Efficient Uplink Transmission in Multi-Loop Wireless Control Systems

This paper proposes a value of information (VoI)-aware energy-efficient uplink transmission scheme to ensure efficient resource allocation and reliable transmission in a multi-loop wireless control system (WCS). In particular, by assuming that the controller is equipped with multiple antennas to manage multiple loops simultaneously, we first formulate an optimization problem that aims to minimize weighted sum of time-average energy consumption and VoI, subject to the constraints of control stability, reliable transmission, and total transmit power budget. Given the long-term nature of the problem, a drift-plus-penalty minimization framework is adopted to transform it into a single-slot optimization problem. Next, a profit-oriented sensor scheduling policy is developed with full consideration of channel conditions, along with a proposed loop-adaptive beamforming scheme to ensure reliable transmission, enabling the WCS to make rapid and accurate decisions. Simulation results demonstrate that in comparison to the benchmarks, the proposed scheme achieves more stable control performance while striking an effective energy-VoI trade-off.