TY - JOUR
T1 - On the Latency, Rate, and Reliability Tradeoff in Wireless Networked Control Systems for IIoT
AU - Liu, Wanchun
AU - Nair, Girish
AU - Li, Yonghui
AU - Nesic, Dragan
AU - Vucetic, Branka
AU - Poor, H. Vincent
N1 - Funding Information:
Manuscript received April 27, 2020; revised June 18, 2020; accepted June 30, 2020. Date of publication July 7, 2020; date of current version January 7, 2021. The work of Wanchun Liu was supported by the Faculty of Engineering Early Career Researcher Development Scheme 2020, University of Sydney. The work of Yonghui Li was supported by ARC under Grant DP190101988. The work of Branka Vucetic was supported by the Australian Research Council’s Australian Laureate Fellowships Scheme under Project FL160100032. (Corresponding author: Yonghui Li.) Wanchun Liu, Yonghui Li, and Branka Vucetic are with the School of Electrical and Information Engineering, University of Sydney, Sydney, NSW 2006, Australia (e-mail: wanchun.liu@sydney.edu.au; yonghui.li@sydney.edu.au; branka.vucetic@sydney.edu.au).
Publisher Copyright:
© 2014 IEEE.
PY - 2021/1/15
Y1 - 2021/1/15
N2 - Wireless networked control systems (WNCSs) provide a key enabling technique for Industrial Internet of Things (IIoT). However, in the literature of WNCSs, most of the research focuses on the control perspective and has considered oversimplified models of wireless communications that do not capture the key parameters of a practical wireless communication system, such as latency, data rate, and reliability. In this article, we focus on a WNCS, where a controller transmits quantized and encoded control codewords to a remote actuator through a wireless channel, and adopt a detailed model of the wireless communication system, which jointly considers the interrelated communication parameters. We derive the stability region of the WNCS. If and only if the tuple of the communication parameters lies in the region, the average cost function, i.e., a performance metric of the WNCS, is bounded. We further obtain a necessary and sufficient condition under which the stability region is n-bounded, where n is the control codeword blocklength. We also analyze the average cost function of the WNCS. Such analysis is nontrivial because the finite-bit control-signal quantizer introduces a nonlinear and discontinuous quantization function that makes the performance analysis very difficult. We derive tight upper and lower bounds on the average cost function in terms of latency, data rate, and reliability. Our analytical results provide important insights into the design of the optimal parameters to minimize the average cost within the stability region.
AB - Wireless networked control systems (WNCSs) provide a key enabling technique for Industrial Internet of Things (IIoT). However, in the literature of WNCSs, most of the research focuses on the control perspective and has considered oversimplified models of wireless communications that do not capture the key parameters of a practical wireless communication system, such as latency, data rate, and reliability. In this article, we focus on a WNCS, where a controller transmits quantized and encoded control codewords to a remote actuator through a wireless channel, and adopt a detailed model of the wireless communication system, which jointly considers the interrelated communication parameters. We derive the stability region of the WNCS. If and only if the tuple of the communication parameters lies in the region, the average cost function, i.e., a performance metric of the WNCS, is bounded. We further obtain a necessary and sufficient condition under which the stability region is n-bounded, where n is the control codeword blocklength. We also analyze the average cost function of the WNCS. Such analysis is nontrivial because the finite-bit control-signal quantizer introduces a nonlinear and discontinuous quantization function that makes the performance analysis very difficult. We derive tight upper and lower bounds on the average cost function in terms of latency, data rate, and reliability. Our analytical results provide important insights into the design of the optimal parameters to minimize the average cost within the stability region.
KW - Industrial Internet of Things (IIoT)
KW - mission-critical communications
KW - performance analysis
KW - sensor-actuator network
KW - wireless networked control
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U2 - 10.1109/JIOT.2020.3007070
DO - 10.1109/JIOT.2020.3007070
M3 - Article
AN - SCOPUS:85099127134
SN - 2327-4662
VL - 8
SP - 723
EP - 733
JO - IEEE Internet of Things Journal
JF - IEEE Internet of Things Journal
IS - 2
M1 - 9134368
ER -