Preface

With the rapid advances in computer science, communication and control techniques, networked control systems (NCSs) have gained wide applications in industry and daily life. The introduction of network brings numerous advantages, such as reduction of wiring, lower cost in maintenance, increased system agility, ease of information sharing, etc., but also causes some new issues, such as delay and packet losses in data transmission. If the occurrence of control packet losses is available to the estimator, the NCS is usually called as the NCSs with packet loss and acknowledgment (ACK), and it is also known as the Transmission Control Protocol-like (TCP-like) system; otherwise, it is called as the NCSs with packet loss without acknowledgment, and it is also known as the User Datagram Protocol-like (UDP-like) system. The NCSs with ACK randomly lost are called the Quasi-TCP-like system. The ACK mechanism does simplify the technical analysis, but in the networked systems it is difficult to implement due to the delay and packet loss. The UDP-like system, at the price of less delivery reliability, avoids unnecessary energy consumption and causes lower latency, making it a preferable choice for NCSs. However, it is technically involved to study the estimation and control issues for this system, many fundamental problems are still unsolved, and there are few effective methods available for the UDP-like systems. Thus, the analysis and synthesis of UDP-like systems are of great importance, and that is what we will do in this book. The features of our book are summarized as follows: