This study is concerned with higher modal parameter estimation of structures ,which is very difficult to estimate with a mathematical model of a relatively larger order. The equation of motion is transformed into the experimental modal equation, and then into the auto-regressive and moving average model with auxiliary stochastic input (ARMAX model) to process the measurement data contaminated by the noise. Then the bandpass filtering technique is utilized for windowing the specified frequency range. The sequential prediction error method is used for the modal parameter estimation. By using the bandpass filter, The higher modes can be identified with the ARMA model of a smaller order.
Verification runs using the simulated data indicate that the present procedure yields good estimates for the higher mode parameters.
