Impedance Spectroscopy Based on Linear System Identification.

Impedance spectroscopy is a commonly used measurement technique for electrical characterization of a sample-under-test over a wide frequency range. Most measurement methods employ a sine wave excitation generator, which implies a point-by-point frequency sweep and a complex readout architecture. This paper presents a fast, wide-band, measurement method for impedance spectroscopy based on linear system identification. The main advantage of the proposed method is the low hardware complexity, which consists of a 3-level pulse waveform, an inverting voltage amplifier and a general purpose ADC. A proof-of-concept prototype, which is implemented with off-the-shelf components, achieves an estimation fit of approximately 96%. The prototype operation is validated electrically using known RC component values and tested in real application conditions.