Comment on ‘Stability analysis and controller synthesis for discrete linear time-delay systems with state saturation nonlinearities’

Abstract

A recently reported paper (Ji, X., Liu, T., Sun, Y., and Su, H. (2011), ‘Stability analysis and controller synthesis for discrete linear time-delay systems with state saturation nonlinearities’, International Journal of Systems Science, 42, 397–406) for the global asymptotic stability analysis and controller synthesis for a class of discrete linear time delay systems employing state saturation nonlinearities is reviewed. It is claimed in Ji, Liu, Sun and Su (2011) that a previous approach by Kandanvli and Kar (Kandanvli, V.K.R and Kar, H. (2009), ‘Robust stability of discrete-time state-delayed systems with saturation nonlinearities: Linear matrix inequality approach’, Signal Processing, 89, 161–173) is recovered from their approach as a special case. It is shown that this claim is not justified.

Keywords:

• discrete linear time-delay system
• global asymptotic stability
• linear matrix inequality
• state saturation

Additional information

Notes on contributors

Siva Kumar Tadepalli

Siva Kumar Tadepalli was born in Warangal, India, in 1978. He received the BE degree from Pt. Ravi Shankar Shukla University, India, in 2002 and the M. Tech. degree from Motilal Nehru National Institute of Technology (MNNIT), Allahabad, India, in 2009. He is currently working towards his PhD degree at MNNIT. His current research interests include finite wordlength effects, multi-dimensional systems, and VLSI.

V. Krishna Rao Kandanvli

V. Krishna Rao Kandanvli was born in Ongole, India, in 1978. He received the B. Tech. degree from Nagarjuna University, India, in 2000, and the M. Tech. and PhD degrees from Motilal Nehru National Institute of Technology (MNNIT), Allahabad, India, in 2005 and 2010, respectively. He joined MNNIT as a lecturer in 2005, where he became an assistant professor in 2006. His current research interests include digital signal processing, nonlinear systems, delayed systems, multi-dimensional systems, and robust stability.

Haranath Kar

Haranath Kar was born in Bankura, India, in 1968. He received the B.E. degree from Bengal Engineering College in 1989, the MTech degree from Banaras Hindu University, Varanasi, India, in 1992 and the PhD degree from University of Allahabad, Allahabad, India, in 2000. After spending a brief period at the Defense Research and Development Organization as a Scientist B, he joined Motilal Nehru National Institute of Technology (MNNIT), Allahabad, India, as a Lecturer in 1991, where he became an assistant professor in 2001, associate professor in 2006 and professor in 2007. He spent two years with the Atilim University, Turkey (2002–2004) as an assistant professor. He served as the Chairman of the Senate Post-Graduate Committee at MNNIT from 2009 to 2010. He is now Head of Electronics and Communication Engineering Department at MNNIT. His current research interests are in digital signal processing, nonlinear dynamical systems, delayed systems, robust stability, guaranteed cost control, and multi-dimensional systems. He is a recipient of the 2002–2003 IEE Heaviside Premium Award. In 2005, he received the D.N. Agrawal Award of excellence for his outstanding services rendered in the field of science and technology. Presently, he is a member of the editorial board of Journal of Engineering.