Systems & control letters vol:49 issue:2 pages:91-98
We first give a brief summary of the arguments that lead to the conclusion that the use of orthogonal rational functions in system identification should not be restricted to the Takenaka-Malmquist basis because there are important cases where orthogonality with respect to a certain nonnegative weight function is required. The main result, however, is a generalization of known state space descriptions for the Takenaka-Malmquist basis to the more general case. This is important for control problems. (C) 2002 Elsevier Science B.V. All rights reserved.