The Local Rational Method Estimates the H-infinity gain using Less Data

In this work we present the use of the Local Rational Method to estimate the H-infinity gain of an Active Vibration Isolation System. The proposed method works by estimating low-order local rational models over the frequency, interpolating them and retaining the largest amplitude of the transfer function of the model-error. On measurements, it has been shown that the LRM-interpolation yields a 7.5 dB improvement in the estimated H-infinity norm and that the estimate is in agreement with four times longer data record. This indicates that the LRM-interpolation is able to provide a reliable H-infinity gain estimate in a very short measurement time.