International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2569

Full Length Research Paper

A passivity criterion for fixed-point state-space digital filters

Choon Ki Ahn1* and Sung-Tae Jung2
  1Department of Automotive Engineering, Seoul National University of Science and Technology, 172 Gongneung 2-dong, Nowon-gu, Seoul 139-743, Korea. 2Department of Computer Engineering, Wonkwang University, 344-2 Shinyong-dong, Iksan 570-749, Korea.
Email: [email protected]

  •  Accepted: 03 March 2011
  •  Published: 04 March 2011



This paper proposes a new criterion for passivity of fixed-point state-space digital filters with saturation arithmetic and external interference. The criterion guarantees not only exponentially stability, but also passivity from the external interference to the output vector. The criterion takes the form of linear matrix inequality (LMI) and, hence, is computationally tractable. An illustrative example is given to demonstrate the effectiveness of the proposed criterion.


Key words: Passivity approach, exponential stability, digital filters, finite wordlength effects, linear matrix inequality (LMI).