NEW STABILITY RESULTS FOR 2-D DISCRETE-SYSTEMS BASED ON THE FORNASINI-MARCHESINI STATE-SPACE MODEL

New conditions for the internal stability of a 2-D discrete system des cribed by the Fornasini-Marchesini (FM) local state-space model are pr esented. Further, the stability margin of a 2-D discrete system descri bed by a (FM) state-space model is considered and methods to compute i t or to obtain lower bounds are developed. These methods are based on the various forms of the Lyapunov equation for 2-D systems. Finally, a sufficient condition for the system to remain stable under parameter variations is presented.