Decentralized control for descriptor type systems

The decentralized robust servomechanism problem [1] for a linear time-invariant system described by: Tx = Ax + Bu + Ew y = Cx + Du + Fw e = y - yref where E may be singular, is considered in this paper, where u, y, e, w denotes the input, output, error and disturbance respectively for the system. In particular, necessary and sufficient conditions to solve the robust decentralized control problem are obtained and a constructive controller synthesis procedure is given for this class of systems. Some simple examples are given to illustrate the result obtained.