Noise leakage suppression in FRF measurements using periodic signals

The steady state response of a system to a periodic input is still corrupted by noise transients. For lightly damped systems these noise transients increase considerably the variance of the measured frequency response function (FRF). This paper presents a method that suppresses the influence of the noise transients (leakage errors) in FRF measurements. The method is based on a local polynomial approximation of the noise leakage errors on the FRF. Compared with the classical approaches, the proposed procedure is more robust and needs less measurement time. The theory is supported by a real measurement example.