A digital signal processing method for measuring frequency response function of high-current devices are described. This is based on a joint digital processing of the input short pulse signal and a corresponding output. In order to measure the frequency response function, a short current pulse is applied to the shunt input; input and output signals of the shunt are recorded in a digital  scilloscope memory; then spectra of these two signals are computed. Amplitude and phase responses are determined by the arithmetic ratio of spectral components of the input and output signals at appropriate frequencies.