H-INFINITY IDENTIFICATION OF MULTIVARIABLE SYSTEMS BY TANGENTIAL INTERPOLATION METHODS

The purpose of this paper is to present an extension to some of the cu rrent work on worst-care identification problems to multivariable syst ems, We consider an H-proportional to-identification problem for a cla ss of linear shift invariant multi-input/multi-output systems. Out mai n results are an interpolatory algorithm and a number of bounds on the identification error, This algorithm operates on available input and output data in the time domain and is constructed by solving an extend ed matrix tangential Caratheodory-Fejer problem. Similar to its counte rpart for scalar systems, this interpolatory algorithm possesses certa in desirable optimality properties and carl Be obtained via standard c onvex programming methods.