The problem of full-order guaranteed cost H-infinity filtering design for discrete-time systems with polytope type uncertainty is investigated in this paper. The main purpose is to obtain a stable and proper linear filter such that the filtering error system remains robustly stable within a prespecified H-infinity, attenuation level. Sufficient conditions for the existence of such robust filter are provided in terms of linear matrix inequalities, which can be efficiently solved by means of high-performance convex optimization procedures with global convergence assured. Moreover, as an improvement, the filter dynamics can be constrained to some specific regions inside the unit open disk. (C) 2000 The Franklin Institute, Published by Elsevier Science Ltd. All rights reserved.3376713723