System for complex impedance measurement

摘要

A measurement system is provided for measuring a complex transfer function of a system under test. The measurement system comprises a signal source for generating an input signal to be applied to the system under test, a signal detection device for detecting a response signal of the system under test in response to the input signal; and a signal analyzing system for determining the gain and phase shift of the system under test by comparing the response signal to the input signal. The signal analyzing system includes phase adjustment means to adjust a relative phase difference of the detected response signal and input signal; and curve fitting means to identify a phase difference adjustment of the phase adjustment means which gives the best fit of the response signal to the input signal. The phase measurement of the response signal is determined from the best fit phase difference adjustment.