Abstract
A new method for approximating scalar discrete linear systems is described. The method can be classified as a time domain/frequency domain technique. Two reduced order models are obtained. One is obtained when the time domain specifications are in terms of the impulse response of the error. The other is derived when the time domain specifications are in terms of the step response of the error. The technique utilizes the input normal system representation to determine the order and the denominator polynomial of the reduced order model.