A new robust stability condition for uncertain discrete-time systems with c
onvex polytopic uncertainty is given. It enables to check stability using p
arameter-dependent Lyapunov functions which an derived from LMI conditions.
It is shown that this new condition provides better results than the class
ical quadratic stability. Besides the use of a parameter-dependent Lyapunov
function, this condition exhibits a kind of decoupling between the Lyapuno
v and the system matrices which may be explored for control synthesis purpo
ses. A numerical example illustrates the results. (C) 1999 Elsevier Science
B.V. All rights reserved.