LAGUERRE METHODS AND H-INFINITY IDENTIFICATION OF CONTINUOUS-TIME SYSTEMS

H infinity identification of stable continuous-time systems is studied using generalized Laguerre series methods. The theoretical basis of generalized Laguerre series methods in H infinity identification is established by giving several results on frequency-unweighted and frequency-weighted approximations of different classes of infinite dimensional systems. An H infinity identification technique based on step response data and Laguerre methods is given and analysed. Generalized Laguerre series methods are shown to provide H infinity identification techniques which allow for frequency weighting. Furthermore, it is demonstrated that the theory of generalized Laguerre polynomials solves certain approximation problems in an analytical fashion for a class of delay systems.