Stabilization of networked control systems under clock offsets and quantization

Kunihisa Okano, Masashi Wakaiki, Guosong Yang, Joao P. Hespanha

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

This paper studies the impact of clock mismatches and quantization on networked control systems. We consider a scenario where the plant's state is measured by a sensor that communicates with the controller through a network. Variable communication delays and clock jitter do not permit a perfect synchronization between the clocks of the sensor and controller. We investigate limitations on the clock offset tolerable for stabilization of the feedback system. For a process with a scalar-valued state, we show that there exists a tight bound on the offset above which the closed-loop system cannot be stabilized with any causal controllers. For higher dimensional plants, if the plant has two distinct poles, then the effect of clock mismatches can be canceled with a finite number of measurements, and hence there is no fundamental limitation. We also consider the case where the measurements are subject to quantization in addition to clock mismatches. For first-order plants, we present necessary conditions and sufficient conditions for stabilizability, which show that a larger clock offset requires a finer quantization.

Original languageEnglish
Pages (from-to)1618-1633
Number of pages16
JournalIEEE Transactions on Automatic Control
Volume63
Issue number6
DOIs
Publication statusPublished - Jun 2018

Keywords

  • Clock offsets, continuous time systems, networked control systems, stabilizability, time-varying sampling periods, quantization

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Computer Science Applications
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Stabilization of networked control systems under clock offsets and quantization'. Together they form a unique fingerprint.

  • Cite this