Packet-drop design in URLLC for real-time wireless control systems

In real-time wireless control systems, ultra-reliable and low-latency communication (URLLC) is critical for the connection between the remote controller and its control objective. Since both transmission delay and packet loss can lead to control performance loss, our goal is to optimize control performance by jointly considering control and URLLC constraints in this paper. To achieve this goal, we formulate an optimal problem to minimize control cost by optimizing the packet drop and wireless resource allocation. To solve the problem, we analyze the relationship between communication and control. Then, based on the relationship, we decompose the original problem into two subproblems: 1) an optimal packet-drop problem to minimize control cost and 2) an optimal resource allocation problem to minimize communication packet error. Finally, the corresponding solutions for each subproblem can be obtained. Compared with the traditional method only considering the communication aspect, the proposed packet-drop and resource allocation method shows remarkable performance gain in terms of control cost

Age of Information for Actuation Update in Real-Time Wireless Control Systems

In this paper, we introduce a generalized definition of age of information (AoI) for actuation update in real-time wireless control systems. In such a system, a general queueing model, i.e., M/M/1/1 queueing model, is used to describe the actuation update, in which the sampling packets arrive at the remote controller following the Poisson process, the process from the controller to the actuator follows the exponential distribution, and the actuation intends to update at the actuator at the predictive time. Then, the initial time of the AoI for the new actuation update is the predictive time for the latest update, which is significantly different from the traditional calculation in status update. By the relationship between communication time from the controller to the actuator and predictive time, the AoI calculation falls into two cases, where the conventional AoI in status update is a specific case in this paper. Simulation results show the performance of our method

Dynamic communication QoS design for real-time wireless control systems

In the coming fifth-generation (5G) cellular networks, ultra-reliable and low-latency communication (URLLC) is treated as an indispensable service to enable real-time wireless control systems. However, the extremely high quality-of-service (QoS) in URLLC causes significant wireless resource consumption. Moreover, to obtain good control performance may not always require extremely high communication QoS. In this paper, we propose a communication-control co-design scheme to reduce wireless resource consumption, where we obtain a dynamic communication QoS design method to reduce the energy consumption by jointly using extremely high QoS and a relatively low QoS. In this scheme, we first explore the control process served by different communication QoS levels and find that the whole control process can be divided into two phases, where different QoS levels have their advantages in different phases. Then, we obtain a threshold to decide when the extremely high QoS or relatively low QoS should be provided by communications. Simulation results demonstrate that our method can effectively reduce communication energy consumption while maintaining good control performance

Internet of Things and Sensors Networks in 5G Wireless Communications

This book is a printed edition of the Special Issue Internet of Things and Sensors Networks in 5G Wireless Communications that was published in Sensors

Internet of Things and Sensors Networks in 5G Wireless Communications

This book is a printed edition of the Special Issue Internet of Things and Sensors Networks in 5G Wireless Communications that was published in Sensors

Internet of Things and Sensors Networks in 5G Wireless Communications

The Internet of Things (IoT) has attracted much attention from society, industry and academia as a promising technology that can enhance day to day activities, and the creation of new business models, products and services, and serve as a broad source of research topics and ideas. A future digital society is envisioned, composed of numerous wireless connected sensors and devices. Driven by huge demand, the massive IoT (mIoT) or massive machine type communication (mMTC) has been identified as one of the three main communication scenarios for 5G. In addition to connectivity, computing and storage and data management are also long-standing issues for low-cost devices and sensors. The book is a collection of outstanding technical research and industrial papers covering new research results, with a wide range of features within the 5G-and-beyond framework. It provides a range of discussions of the major research challenges and achievements within this topic