Pole assignment for uncertain symmetric circulant composite systems in a specified disk

Regional pole assignment for a kind of uncertain symmetric circulant composite system by state feedback in a specified disk is discussed. The 'decentralised D stabilisation controllers' have been obtained by making use of the special structure of the system. Thus the problem of assigning the poles in a specified disk for such an uncertain system with N /spl middot/ n dimensions can be transformed into the subproblems for N/2+1 or (N+1)/2 uncertain systems with n dimensions. The central D stabilisation controller for such a system has the same block symmetric circulant structure as the original system and can be constructed by the 'decentralised D stabilisation controllers'.