The invention relates to a time domain method for obtaining transfer characteristics of a device under test (DUT). The method comprises the steps of applying a sine sweep and a cosine sweep to an input of the DUT, and measuring response signals at an output of the DUT. The sine sweep and cosine sweep together establish a complex input signal, whereby to each instant there is related a particular frequency. Similarly, the respective response signals together establish a complex response signal. The magnitudes and phases of both complex signals are calculated and the transfer characteristics of the DUT then follow from the magnitude ratio and the phase difference of the input signal and the response signal. The invention also relates to an arrangement for testing transfer characteristics of a DUT and to an integrated circuit comprising the necessary elements for testing a subcircuit contained therein.