Efficient and de-noising calculation for extracting impulse response function in time-domain

Abstract

ABSTRACT Impulse response function (IRF) and frequency response function (FRF) are the bases and preconditions for acquiring the parameters of a dynamic system and accurately obtaining the dynamic response of the system both in time and frequency domains. In the test of dynamic characteristics of a structural system, for some cases, it is not suitable to use the average power spectrum and cross-spectrum methods to obtain the FRF of the system. This paper studies the methods of extracting the IRF in the time domain, where the measured input and output signals contain white Gaussian noise. According to Duhamel’s integral and the time-domain averaging technique, an efficient average recursive (AR) algorithm with anti-noise performance is proposed to obtain the impulse response function. In the AR method, it is assumed that the input and output data of the system are composed of white Gaussian noise with a mean value of zero. The proposed AR algorithm avoids the inversion of a larger matrix and improves the efficiency of calculation. Simulation and experimental results show that it has apparent advantages in computing efficiency and de-noising.