A Novel Method for Modal Parameters Estimate Based on RDT – ARMA with Measured Acceleration

Large structure modal parameter estimation has always been an important research content. Its core content is to obtain the eigenvalues of large-scale structural system. Based on the environmental excitaion, to obtain high precision system free response is particularly important. This paper presents a random reduction de-noising-ARMA method(RDT-ARMA method). By analyzing the characteristics of free response root and imaginary part under the condition of health and damage, the noise modal of free response obtained by stochastic reduction method can be effectively eliminated to obtain a more realistic system free response signal. Based on this, the modal of large structural system is identified by ARMA method. And through the actual acquisition of the WSN signal processing measured acceleration, indicating the effectiveness of the proposed method can be proved.