Minimização do consumo de energia por bit para sistemas de controle em rede sem fio com abordagem de tempo de permanência

Abstract

Wireless networked control systems are a class of systems where communication between sensors, actuators and controllers occurs through a shared bandwidth. This type of system has a wide application area, since it can be incorporated in situations where space is limited and when implementation cost reduction is required. In addition, wireless control systems have wide application within machine-to-machine communications, a fundamental part of 5G systems. In this context, it is of fundamental importance to guarantee the stability of the control system, at the same time that the transmission process must occur within the shortest possible delay. Moreover, due to the size and cost restrictions of these systems, it is common for wireless control systems to be powered by batteries. Therefore, the total energy consumed by the system must be taken into account. Therefore, this work focuses on the minimization of the energy consumed per transmitting bit, with the restriction that the stability of the control system must be guaranteed. Using the dwell time approach, which is a sufficient condition to obtain stability, it was possible, through the optimization of outage probability, to minimize energy consumption per bit. We conclude that the distance between the transmitter and the receiver directly interferes with the system's power consumption per bit, since the transmission power depends on the distance between the transmitter and the receiver. Finally, it was possible to obtain a closed-form expression that relates the maximum outage probability that the system can operate with the stability of the control system.