Measurement of Impedance Parameter Using Non-Sinusoidal Periodic Wave

This paper presents a new impedance measurement technique based on the theory of digital signal processing. The power source of this method can be any periodic signal and its signal-to-noise ratio can be relatively low (SNR 5dB).A special digital quadrature sampling arithmetic with high mirror frequency rejection is adopted to get I&Q sequences which are used to confirm the parameters of the impedance under measurement. Computer simulation and experimental results show that this method takes on the characters of wide measurement range and high accuracy.